Recreational Fisheries Overview
155 Questions
7 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following best defines recreational fisheries?

  • Fishing that is solely performed for competitive sport.
  • Fishing for aquatic animals primarily to sell at market.
  • Fishing for enjoyment, social connection, and possibly for food, without commercial intent. (correct)
  • Fishing activities undertaken strictly for scientific research.

    • What is a common objective for recreational fisheries compared to commercial fisheries?

  • Ensuring the highest financial return on invested resources.
  • Focusing solely on profit maximization without concern for sustainability.
  • Maximizing annual yield to prevent species extinction.
  • Providing unique fishing experiences that do not prioritize catch quantity. (correct)

    • Which factor is NOT typically considered an objective for management in recreational fisheries?

  • Preventing localized depletion of fish populations.
  • Meeting specific annual profit margins for operators. (correct)
  • Maximizing recreational fishing opportunities.
  • Minimizing negative environmental impacts from fishing activities.

    • What significant trend is highlighted regarding the number of recreational fishers compared to commercial fishers?

    <p>Recreational fishers outnumber commercial fishers by a large margin.</p> Signup and view all the answers

    Which management leverage is used to study recreational fisheries in Western Australia?

    <p>Bi-annual phone diaries from recreational fishers.</p> Signup and view all the answers

    What trend was observed in global recreational catch estimates between the mid-1980s and 2014?

    <p>Consistently increased to approximately 900,000 t·year-1 by 2014.</p> Signup and view all the answers

    Which region is specifically highlighted as having declining recreational catches?

    <p>Oceania</p> Signup and view all the answers

    How does catch-and-release mortality impact the understanding of recreational fishing mortality?

    <p>It likely contributes significantly but is not fully accounted for, except in the USA.</p> Signup and view all the answers

    What factor contributed to the variation in recreational catch trends across different global regions?

    <p>Economic stability and growth in emerging economies.</p> Signup and view all the answers

    In the context of marine catch reconstructions, which of the following best characterizes the data collection methodology used for recreational catches?

    <p>Independent reconstructions were conducted for 125 countries to assess recreational catches.</p> Signup and view all the answers

    What accurately differentiates food security from food supply in the context of nutrition?

    <p>Food security aims to alleviate hunger and malnutrition, while food supply is concerned with economic aspects of food distribution.</p> Signup and view all the answers

    How does fish contribute significantly to nutrition in developing countries?

    <p>Fish provides essential micronutrients and proteins that enhance dietary balance.</p> Signup and view all the answers

    What is a major consequence of declining fish catches in terms of food security?

    <p>It exacerbates malnutrition, particularly among populations reliant on fish as a primary food source.</p> Signup and view all the answers

    Which factor is a significant threat to fish populations and subsequently affects food security?

    <p>Illegal foreign industrial fishing and high population pressure.</p> Signup and view all the answers

    What is the relationship between climate change and fisheries management?

    <p>Climate change poses challenges such as weakened governance and threatens fish stock sustainability.</p> Signup and view all the answers

    What is the main ratio associated with estimated catches destined for fishmeal and fish oil production compared to their final product output?

    <p>5:1</p> Signup and view all the answers

    Which type of fishing country has recently transformed due to increased Chinese fishing activities?

    <p>Countries with no FMFO production from by-products</p> Signup and view all the answers

    Which of the following categorizes fishing countries based on their production practices?

    <p>Countries with dedicated reduction fisheries, by-products dominance, and no production</p> Signup and view all the answers

    The shift in classification of certain West African countries in the fishing industry was primarily driven by which factor?

    <p>Chinese fishing activities</p> Signup and view all the answers

    What has been a significant trend observed in the historical analysis of marine fisheries from 1950 to 2010?

    <p>Variability in landings influenced by market fluctuations</p> Signup and view all the answers

    What is the primary economic contribution of commercial fisheries in Western Australia?

    <p>$300 million</p> Signup and view all the answers

    Which of the following species is NOT listed as a key recreational target species in Western Australia?

    <p>Australian sardines</p> Signup and view all the answers

    How many commercial fisheries are currently operating in Western Australia?

    <p>50</p> Signup and view all the answers

    What proportion of Western Australia's population engages in recreational fishing?

    <p>About 25%</p> Signup and view all the answers

    Which types of aquatic resources does DPIRD manage in Western Australia?

    <p>All bony fish, shark, aquatic invertebrates, marine algae, and seagrass</p> Signup and view all the answers

    What is a significant demographic impacted by malnutrition that results in immediate health consequences?

    <p>Children under the age of five</p> Signup and view all the answers

    Which of the following statements best characterizes the economic implications of malnutrition worldwide?

    <p>Malnutrition decreases educational potential, leading to economic stagnation.</p> Signup and view all the answers

    What is one of the primary reasons seafood is considered a highly traded food commodity?

    <p>The average annual production volume of 105 million tonnes.</p> Signup and view all the answers

    What are the consequences of nutrient deficiencies that extend beyond individual health?

    <p>Higher rates of morbidity and mortality.</p> Signup and view all the answers

    Which statistic accurately represents a facet of overweight and obesity as a form of malnutrition?

    <p>1.9 billion adults globally are classified as overweight or obese.</p> Signup and view all the answers

    What is the main factor contributing to the decline of shark populations globally?

    <p>Overfishing driven by fishing practices</p> Signup and view all the answers

    Which conservation approach is noted to be particularly dependent on context and location?

    <p>Design of marine protected areas (MPAs)</p> Signup and view all the answers

    How do biologging technologies, such as accelerometers, benefit the study of shark behavior?

    <p>They deliver fine-scale data on 3D movement and behavior</p> Signup and view all the answers

    Which of the following statements accurately distinguishes artisanal fishing from commercial fishing practices?

    <p>Artisanal fishing typically targets local consumption, whereas commercial fishing focuses on profit from larger markets.</p> Signup and view all the answers

    What is a significant issue related to bycatch in fishing practices that affects marine populations?

    <p>Accidental capture of non-target species leading to population decline</p> Signup and view all the answers

    What method is used to assess recreational fishing activity within and near the wind farm area?

    <p>Recreational boat ramp survey</p> Signup and view all the answers

    Which strategy is NOT mentioned for minimizing impacts on fish populations during construction activities?

    <p>Enhancing fish breeding programs</p> Signup and view all the answers

    Which fisheries data source provides information on surface fish schools and fishing activity in the area?

    <p>Aerial survey data</p> Signup and view all the answers

    What communication strategy is recommended to minimize impacts on fishers?

    <p>Provide alternative work opportunities or compensation</p> Signup and view all the answers

    Which survey method includes consultation with fishers and peak bodies before the actual survey takes place?

    <p>Recreational boat ramp survey</p> Signup and view all the answers

    What aspect of the term 'Illegal, Unreported and Unregulated' (IUU) is considered problematic in fisheries discussions?

    <p>It merges questions about legality, reporting, and management.</p> Signup and view all the answers

    What is the legal implication of using the term IUU for fisheries management?

    <p>It can lead to ambiguities in defining illegal fishing activities.</p> Signup and view all the answers

    When considering distant-water fishing, what is the commonly accepted international definition?

    <p>Fishing outside a country's Exclusive Economic Zone or on the high seas.</p> Signup and view all the answers

    How does IUU fishing impact marine ecosystems?

    <p>It disrupts local fish stocks and depletes resources.</p> Signup and view all the answers

    Why is it recommended to avoid using the term 'IUU' in scientific discussions about fisheries?

    <p>It can obscure the individual issues of illegal, unreported, and unregulated fishing.</p> Signup and view all the answers

    Which factor significantly influences the type of discards observed in a fishery?

    <p>Social and political factors such as quota regulations</p> Signup and view all the answers

    Which fishing gear type is associated with the highest potential for bycatch, leading to increased discards?

    <p>Bottom trawls</p> Signup and view all the answers

    How does market demand influence fish discards in commercial fisheries?

    <p>Low prices for certain fish lead to their increased discarding</p> Signup and view all the answers

    Which of the following statements best describes the relationship between gear selection and discarding behavior?

    <p>Fisheries using highly selective gears experience lower discard rates</p> Signup and view all the answers

    What is a primary geographic factor that influences discarding patterns in fisheries?

    <p>Environmental conditions of specific fishing grounds</p> Signup and view all the answers

    What is a critical outcome identified from the industrial fisheries practices according to Myers and Worm?

    <p>Reduction in the community biomass of large predatory fishes by 80%</p> Signup and view all the answers

    Which management approach does Hilborn advocate for in addressing the fisheries crisis?

    <p>Standard fisheries methods with robust regulations</p> Signup and view all the answers

    What is a significant difference in perspective between Ray Hilborn and Daniel Pauly regarding fisheries management?

    <p>Hilborn supports only traditional approaches, while Pauly recommends a mix of strategies.</p> Signup and view all the answers

    Which aspect significantly affects individual's perspectives on the degree of the fisheries crisis?

    <p>Background and professional experience</p> Signup and view all the answers

    What does the evidence suggest regarding the management of fish stocks in various regions?

    <p>Rebuilding stocks is possible in many locations with proper management.</p> Signup and view all the answers

    What happens to stock productivity when stock size is reduced from unfished levels?

    <p>It initially increases, reaches a maximum, then declines.</p> Signup and view all the answers

    Which parameter is NOT included in Russell's axiom for recruitment dynamics?

    <p>Carrying capacity (K)</p> Signup and view all the answers

    In the context of sustainable catch, what does surplus production refer to?

    <p>The additional productivity generated by fishing.</p> Signup and view all the answers

    Which factor contributes to the variability in growth, recruitment, and natural mortality rates in fish populations?

    <p>Random variability within specified limits.</p> Signup and view all the answers

    What is a consequence of fishing a stock too low, according to the simulation results?

    <p>Sustainable catch decreases to very low levels.</p> Signup and view all the answers

    Which of the following best characterizes the primary goal of the subsistence fishing sector?

    <p>Providing for personal and community sustenance primarily.</p> Signup and view all the answers

    What distinguishes the industrial fishing sector from the artisanal sector?

    <p>Industrial fishing often utilizes advanced technology and large vessels.</p> Signup and view all the answers

    In which way do recreational fisheries differ from commercial fisheries?

    <p>Recreational fisheries are mainly focused on pleasure rather than economic gain.</p> Signup and view all the answers

    Which statement best describes a characteristic of the small-scale fishing sector?

    <p>Small-scale fishing often involves traditional methods and caters to local communities.</p> Signup and view all the answers

    What is a significant characteristic that differentiates large-scale fishing from small-scale fishing?

    <p>Large-scale fishing often involves significant capital investment and extensive operations.</p> Signup and view all the answers

    How do Marine Protected Areas (MPAs) contribute to fish stock sustainability?

    <p>MPAs function as breeding grounds, allowing fish populations to rebuild.</p> Signup and view all the answers

    What potential impact does climate change have on fisheries management?

    <p>Altered fish migration patterns may necessitate adjustments in management strategies.</p> Signup and view all the answers

    Which of the following best describes the significance of the Fishing Access Database?

    <p>It records fishing access agreements and observed fishing activities in different EEZs.</p> Signup and view all the answers

    What is a primary goal of the spatial allocation of catch data in fisheries studies?

    <p>To identify ecologically significant areas for targeted fish stocks.</p> Signup and view all the answers

    What does a disconnect between demand and supply capacity imply for global fisheries?

    <p>There could be overfishing as demand exceeds sustainable supply limits.</p> Signup and view all the answers

    What is a significant environmental impact associated with bottom trawling?

    <p>It contributes to loss of biodiversity by damaging seabed ecosystems.</p> Signup and view all the answers

    Which of the following statements about dynamite fishing is accurate?

    <p>It is illegal and considered highly destructive to fish populations and habitats.</p> Signup and view all the answers

    What historical context contributed to the prevalence of cyanide fishing?

    <p>The rise of the aquarium trade and demand for live fish drove its popularity.</p> Signup and view all the answers

    What is a major reason for the classification of active bottom contact gears as the most destructive fishing gear globally?

    <p>They lead to higher rates of bycatch and habitat destruction.</p> Signup and view all the answers

    How does cyanide fishing specifically impact marine ecosystems beyond fish populations?

    <p>It causes high delayed mortality and damages coral ecosystems.</p> Signup and view all the answers

    What is the primary difference between Maximum Sustainable Yield (MSY) and Maximum Economic Yield (MEY)?

    <p>MSY focuses solely on stock replenishment rates, while MEY includes economic considerations.</p> Signup and view all the answers

    Which of the following accurately describes a significant ecological impact of implementing reduced fishing efforts?

    <p>Enhanced ecosystem resilience resulting from the higher biodiversity.</p> Signup and view all the answers

    What is one potential negative economic consequence of maintaining fishing efforts at the lower end of MEY?

    <p>Reduced employment opportunities in the fishing industry.</p> Signup and view all the answers

    What key factor led to the implementation of new gear modifications to address the TEPS interactions?

    <p>High concern for the welfare of endangered species and ensuring their conservation.</p> Signup and view all the answers

    Which statement best reflects the implications of TEPS (Threatened, Endangered, and Protected Species) monitoring for fisheries management?

    <p>Comprehensive monitoring may lead to reduced fishing seasons to protect ecosystem balance.</p> Signup and view all the answers

    What concept describes the maximum yield that can be taken from a fish stock over an indefinite period under constant environmental conditions?

    <p>Maximum sustainable yield</p> Signup and view all the answers

    Which of the following stock-recruitment models incorporates changes in recruitment based on varying stock sizes and densities?

    <p>Beverton and Holt model</p> Signup and view all the answers

    In surplus production theory, what happens when production (P) exceeds mortality (M)?

    <p>Population biomass is growing.</p> Signup and view all the answers

    Which statement accurately defines depensation in terms of fish stock dynamics?

    <p>Recruits increase as spawning stock increases.</p> Signup and view all the answers

    What is the implication of reaching the carrying capacity (B0) regarding surplus production and population growth?

    <p>Population remains unchanged as P equals M.</p> Signup and view all the answers

    What parameter represents the rate at which a growth curve approaches the length limit in fish growth modeling?

    <p>K</p> Signup and view all the answers

    Which method for estimating fish mortality rates involves tracking individual fish over time?

    <p>Mark-recapture methods</p> Signup and view all the answers

    In the context of fish mortality, what does the equation Z = M + F represent?

    <p>Total mortality is the sum of natural mortality and fishing mortality.</p> Signup and view all the answers

    What does the variable Z signify in fisheries mortality analysis?

    <p>Total mortality rate</p> Signup and view all the answers

    Among the following methods, which one is primarily based on the length of fish for assessing mortality?

    <p>Age- or length-based catch curves</p> Signup and view all the answers

    What is the primary reason for the need to standardize fishing effort data across different fisheries?

    <p>To enable comprehensive comparisons of fish populations across different locations</p> Signup and view all the answers

    What has been the effect of increased motorization of small-scale fisheries from the 1960s to 1980s?

    <p>Increase in fishing efficiency leading to overfishing</p> Signup and view all the answers

    Which statement best describes the relationship between catch per unit effort (CPUE) and fish stock health?

    <p>Higher CPUE is indicative of declining fish stocks due to overfishing</p> Signup and view all the answers

    What issue is commonly observed with the data reporting and management of fishing efforts?

    <p>Data reporting often lacks completeness or is inconsistent</p> Signup and view all the answers

    How has the concept of fishing effort adjusted in relation to spatial coverage of fisheries?

    <p>Localized practices necessitate unique assessments of fishing effort</p> Signup and view all the answers

    What is a key difference between industrial and artisanal fisheries based on their operational scale?

    <p>Industrial fisheries require large investments for construction and maintenance.</p> Signup and view all the answers

    What methodology is employed in catch reconstruction to enhance the accuracy of fisheries data?

    <p>Incorporating both landings and discards for comprehensive assessments.</p> Signup and view all the answers

    In the context of fishing sectors, which characteristic best defines subsistence fishing?

    <p>Performed mainly by women and children for community consumption.</p> Signup and view all the answers

    What is the primary rationale for conducting catch data analysis in fisheries management?

    <p>To ensure sustainable practices and assess the health of fish populations.</p> Signup and view all the answers

    Which characteristic is typically associated with industrial fisheries that differentiates them from other sectors?

    <p>They are larger operations that often overfish due to high demand.</p> Signup and view all the answers

    What was the primary aim of the Whale Protection Act passed by the Australian government?

    <p>To effectively end commercial whaling in Australian waters.</p> Signup and view all the answers

    What is one potential consequence of developed nations importing more seafood from countries with little bycatch monitoring?

    <p>Effective export of bycatch issues to other nations.</p> Signup and view all the answers

    Which of the following best reflects the complexity of current seafood demand in developed nations?

    <p>Regulated fisheries facing high demand leading to potential environmental trade-offs.</p> Signup and view all the answers

    What approach is emphasized for scientists and researchers when addressing marine conservation issues?

    <p>Maintaining objectivity and considering complex interactions in ecosystems.</p> Signup and view all the answers

    In the context of stakeholder communication regarding marine conservation, what is one critical aspect to consider?

    <p>Engaging stakeholders through evidence-based discussions and risk assessments.</p> Signup and view all the answers

    What is the expected global impact on the body weight of fish species as a result of increased water temperatures?

    <p>Body weight is expected to shrink by 14-24% in fish globally.</p> Signup and view all the answers

    How does increased ocean acidity impact marine organisms dependent on calcium carbonate?

    <p>It reduces shell formation and can dissolve their existing shells.</p> Signup and view all the answers

    What is the predicted rise in sea level by 2100 based on current estimates?

    <p>1-2 meters under conservative models.</p> Signup and view all the answers

    What is the consequence of lower pH on the otolith development in fish?

    <p>It affects their sensory perception and balance negatively.</p> Signup and view all the answers

    Which factor is most closely associated with declining marine biodiversity in warm waters?

    <p>The reduction of oxygen levels in warmer waters.</p> Signup and view all the answers

    What is a significant resource utilized for gathering information about marine species in FishBase?

    <p>Baited remote underwater video systems</p> Signup and view all the answers

    Which of the following categories is not utilized for organizing species information in FishBase?

    <p>Geographic distribution</p> Signup and view all the answers

    What type of information does FishBase primarily focus on when detailing species?

    <p>Nutritional value</p> Signup and view all the answers

    The effort to digitize 600 note cards into a database exemplifies which key aspect of FishBase?

    <p>Focus on equity and free access</p> Signup and view all the answers

    What is one of the main factors contributing to the organization of FishBase’s species information?

    <p>Gill surface area</p> Signup and view all the answers

    Which of the following is NOT a primary purpose of marine protected areas?

    <p>Develop recreational fishing</p> Signup and view all the answers

    What percentage of fisheries are considered unsustainable?

    <p>33%</p> Signup and view all the answers

    Which IUCN zoning category typically allows for various forms of exploitation?

    <p>IUCN III-VI</p> Signup and view all the answers

    Which species has experienced the highest reported decline in population among the following?

    <p>Hammerhead shark</p> Signup and view all the answers

    Which year marked the peak fish catch according to the data provided?

    <p>1996</p> Signup and view all the answers

    What was a consequence of the introduction of Nile tilapia to native fish species?

    <p>Two endemic species became extinct due to competitive replacement.</p> Signup and view all the answers

    Which factor has contributed significantly to the decline of trout populations in freshwater ecosystems?

    <p>Climate change and pollution causing warmer waters and reduced oxygen.</p> Signup and view all the answers

    What impact do dams have on the Tana River Delta's ecosystem?

    <p>Dams lead to degradation of mangroves due to inadequate freshwater flows.</p> Signup and view all the answers

    How does aquaculture differ from wild catch in terms of ecological impact?

    <p>Aquaculture typically causes more invasive species introduction than wild catch.</p> Signup and view all the answers

    What serves as an important indicator of ecosystem health related to fisheries?

    <p>The health of macroinvertebrates and water quality indicators.</p> Signup and view all the answers

    What might contribute to the inaccurate perceptions of rising trends in inland fisheries production?

    <p>Inconsistent reporting frameworks across countries</p> Signup and view all the answers

    What distinguishes small-scale fisheries from large-scale industrial fisheries?

    <p>Small-scale fisheries operate with minimal technology and labor</p> Signup and view all the answers

    Which statement best reflects a challenge regarding data collection in inland fisheries?

    <p>Absent data collection systems lead to false representations of catch data.</p> Signup and view all the answers

    How does the presence of industrial fisheries impact the sustainability of small-scale fishing communities?

    <p>Industrial fisheries compete for the same fish stocks, affecting the availability.</p> Signup and view all the answers

    What role does irrigation play in affecting freshwater fisheries?

    <p>Irrigation schemes often lead to pollution and habitat alteration.</p> Signup and view all the answers

    What is a key benefit of integrating historical sources with marine science methodologies?

    <p>Standardizing catch per unit effort (CPUE) across diverse marine environments</p> Signup and view all the answers

    How does historical analysis contribute to understanding the evolution of conservation efforts?

    <p>By providing references to past biodiversity and fishing practices</p> Signup and view all the answers

    What role does interdisciplinary collaboration play in overcoming Shifting Baseline Syndrome?

    <p>It facilitates innovative methodologies for understanding historical ecological changes</p> Signup and view all the answers

    Which of the following accurately describes Shifting Baseline Syndrome in the context of marine ecosystems?

    <p>It reflects a gradual adjustment in expectations based on contemporary environmental conditions</p> Signup and view all the answers

    In what ways does cultural context influence the understanding of marine fisheries history?

    <p>Cultural insights help clarify spatial patterns and technological advancements in fishing</p> Signup and view all the answers

    What is the function of the parameter $r$ in the AMSY methodology?

    <p>It represents the resilience or productivity of the species.</p> Signup and view all the answers

    Which of the following is a main assumption of the AMSY methodology regarding CPUE?

    <p>There exists a direct proportionality between CPUE and biomass.</p> Signup and view all the answers

    What does the LBB approach primarily estimate in fisheries science?

    <p>The relative fishing mortality and natural mortality.</p> Signup and view all the answers

    Which statement best describes the uncertainty associated with the estimates of F/FMSY in AMSY results?

    <p>It demonstrates high uncertainty due to the absence of data on catch.</p> Signup and view all the answers

    In biomass estimation, the parameter $q$ represents what aspect in the context of CPUE?

    <p>The catchability of the target species based on various fishing methods.</p> Signup and view all the answers

    What is one of the main purposes of vessel buyback programs in fisheries management?

    <p>To reduce fishing pressure</p> Signup and view all the answers

    Which of the following is NOT a potential negative outcome of fisher assistance programs?

    <p>Enhanced training for other economic sectors</p> Signup and view all the answers

    Which factor is considered in calculating the costs of maintaining Marine Protected Areas (MPAs)?

    <p>The size of the MPA</p> Signup and view all the answers

    What is a key objective of research and development (R&D) programs in fisheries?

    <p>To improve fish catching and processing methods sustainably</p> Signup and view all the answers

    Which of the following types of socio-economic studies is associated with fishery research?

    <p>Fishery socio-economic studies</p> Signup and view all the answers

    Which consequence level indicates impacts are detectable but have limited effects on population dynamics?

    <p>Minor</p> Signup and view all the answers

    What does the risk framework categorize as 'severe' in terms of fishing management?

    <p>Unacceptable level affecting future recruitment</p> Signup and view all the answers

    Which factor is primarily used to drive the model in assessing fishing mortality and biomass?

    <p>Catch history</p> Signup and view all the answers

    In fisheries management, how is spawning stock biomass generally assessed?

    <p>Using age-based integrated models</p> Signup and view all the answers

    What is the consequence of elevated fishing mortality levels on relative female spawning biomass when using CPUE data?

    <p>Low current female spawning biomass</p> Signup and view all the answers

    What is a potential issue with taxonomic resolution in catch data related to tuna fisheries?

    <p>Inconsistent identification of closely related species.</p> Signup and view all the answers

    What challenge is commonly faced in catch reporting within the fisheries management context?

    <p>Discrepancies between reported and actual catches due to IUU activities.</p> Signup and view all the answers

    How does a Kobe plot assist in the management of tuna stocks?

    <p>It visualizes the relationship between stock status and fishing pressure.</p> Signup and view all the answers

    What aspect of Regional Fisheries Management Organizations (RFMOs) contributes to challenges in assessing stock status?

    <p>Consensus-based decision making that delays urgent actions.</p> Signup and view all the answers

    What is a key factor influencing the accuracy of stock assessments for highly migratory species?

    <p>Consistency in data collection methods among different regions.</p> Signup and view all the answers

    Study Notes

    Recreationalsheries: What are they?

    • Definition: Fishing for aquatic animals primarily for enjoyment, sport, and social connection. It doesn’t meet basic nutritional needs, nor is it intended for sale.

    • Location: Occurs globally, with an estimated 100 million people participating. In certain areas, there are more recreational fishers than commercial fishers.

    Western Australia

    • Magnitude: Recreational fishing in Western Australia totals 4.2billioninexpenditures,whichisalmostdoublethe4.2 billion in expenditures, which is almost double the 4.2billioninexpenditures,whichisalmostdoublethe2.734 billion generated from commercial fisheries.

    • Management Tools: Bi-annual phone diary, boat ramp surveys, and boat ramp cameras are used to understand and manage recreational fishing.

    Research Focus

    • Shark Depredation: The impact of sharks on recreational fisheries is a crucial research area.
    • Localized Depletion: Studies examine the impact of localized fishing pressure on specific fish populations.
    • No-Take Marine Reserves: Research explores the effects of no-take zones on recreational fisheries and fish populations.

    Objectives of Recreational Fisheries

    • Commercials vs. Recreationals: Objectives differ from commercials:

      • Commercials aim for maximum sustainable yield (MSY) and maintain fish biomass for commercial production.
      • Recreationals focus on fishing experiences, catch rates, and fish variety.

    • Fishing Experience: Factors influencing a good fishing experience include:

      • Fish stock : Catch rates of desired fish species and variety
      • Infrastructure: Quality of boat ramps and fishing facilities
      • External Factors : Weather, company, and skill level

    Management Levers

    • Soft vs. Hard Regulations: Recreationals are managed differently than commercials.
      • Soft regulations: Bag limits, size limits, and seasonal closures
      • Hard regulations: Catch quotas and effort quotas - set limits on how much each fisher can catch.

    Western Australia's West Coast Demersal Scalefish Fishery:

    • Overfishing: The fishery has been in a depleted state since 2007.
    • Current State: Management efforts are ongoing, with potential solutions being considered.

    Case Studies

    • Case Study 1: Studies on fisher behavior reveal that access to fishing spots (minimal travel cost) and being sheltered from weather are more important for fishers than catching one additional fish.

    • Case Study 2: Choice experiments gather information from fishers about their management preferences:

      • Fishers dislike the idea of required fishing tags and removing size limits.
      • They prefer extended seasonal closures to harder management restrictions.

    Take Home Points

    • The goals of recreational and commercial fisheries are not the same.
    • Diverse factors influence fishing experiences, not just catching fish.
    • Soft regulations are prevalent in the management of recreational fisheries.
    • Overfishing is a risk when recreational fishing participation increases.
    • Studying fisher behavior helps to identify what is crucial for a good fishing experience.
    • Access, catch rates, and shelter are essential for recreational fishing in Western Australia.
    • Choice experiments reveal fisher preferences for different management methods.
    • Longer seasonal closures are more favored than hard limits like tagging systems.

    Australia

    • In Australia, recreational fishing is a popular pastime
    • Records for Australian recreational fishing prior to the 1970s are scarce, making it difficult to assess historical effort and catch.
    • Historically, fisheries managers underestimated the impact of recreational fishing compared to commercial fishing.
    • Increased fishing participation from the 1970s to the 1990s led to a greater understanding of recreational fishing's impact, revealing that in certain locations and species recreational catches can surpass those of commercial fisheries.

    Global Recreational Catch

    • Global recreational catches have grown significantly since the 1950s, reaching approximately 900,000 tons per year by 2014.
    • These catches represent less than 1% of total global marine catches.
    • While some regions like North America, Europe and Oceania have experienced a decline in recreational fishing, other areas like South America, Asia and Africa are witnessing an increase.
    • The rise in recreational fishing in emerging economies is partially attributed to the decline in popularity in North America.
    • It is crucial to note that catch-and-release mortality is not fully accounted for in global recreational catch estimates, except in the USA.
    • This poses an important challenge, as catch-and-release mortality can significantly influence the actual impact of the practice on fish populations.

    USA Recreational Fishing

    • The USA has a significant recreational fishing sector.
    • Recreational fishing data in the USA is more extensive than Australia, allowing for better understanding of historical trends.
    • Different regions within the USA demonstrate varying trends:
      • East Coast: Reconstructed data shows a peak in recreational catches in the 1980s.
      • West Coast: Data showcases a stable trend in recreational catches.
      • Alaska: The state faces a challenge in distinguishing between recreational and subsistence fishing, making it difficult to assess precise catch numbers.
      • Hawaii: Historical catch reconstruction for reef- and bottom-fisheries shows notable trends from 1950-2002.

    Food Security vs. Food Supply

    • Food security focuses on alleviating hunger and malnutrition, especially in developing countries.
    • Food supply focuses on economic activity and providing diverse food items to consumers.
    • While both concepts involve food, they differ in their focus:
      • Food security prioritizes addressing malnutrition and providing essential nutrients.
      • Food supply emphasizes supplying food as a commodity for economic gain.

    Importance of Fish for Food Security

    • Over 678 million people were undernourished in 2018, with an estimated increase to over 840 million by 2030.
    • Fish provides a critical source of essential nutrients and micronutrients in developing countries, where diets often lack these elements.
    • Fish plays a crucial role in addressing malnutrition in developing countries, supplementing inadequate diets with protein and micronutrients.

    Declining Fish Catches and Food Security

    • Declining fish catches threaten human health, particularly in developing countries that depend on wild fish for food.
    • This decline is attributed to several factors including:
      • Illegal industrial fishing
      • Weak governance
      • Poor stock status knowledge
      • High population pressure
      • Climate change

    Fisheries: A Public Health Asset

    • Fish is a significant dietary component for over 3 billion people.
    • Fish provides approximately 7% of global protein intake and 17% of global animal protein intake.
    • In developing countries, local fisheries offer a sustainable solution for addressing malnutrition by providing access to essential nutrients.
    • Overfishing, industrial fishing targeting export markets, climate change, fishmeal export factories, and international trade pose a threat to local fisheries and their ability to contribute to food security.

    Two Differing World Views of Fisheries

    • Two differing world views exist:
      • Economic Commodity: Fish is seen as an economic commodity, with industrial fisheries targeting high-income markets.
      • Human Health Asset: Fish is regarded as crucial for human health and food security, particularly in developing countries.

    The Need for Policy Reform

    • Policy reforms should shift focus from "fisheries as a commodity provider" to "fisheries as a domestic public health asset" to ensure food and nutrient security.
    • Addressing this issue requires a shift in perspective, challenging policymakers to move beyond economic considerations and recognize the critical role of fisheries in human health and food security.

    End use of Marine Fisheries Landings

    • Landings are categorized into three end-use categories: Direct Human Consumption (DHC), Fish Meal and Fish Oil (FMFO) and Other (e.g. direct feed, fertilizer, industrial use).
    • DHC: refers to catches intended for direct consumption by humans.
    • FMFO: encompasses catches processed into fish meal and fish oil for animal feed and other industrial applications.
    • Other: includes catches used as direct feed, fertilizer or for industrial purposes.
    • The analysis includes all industrial and artisanal landings, excluding subsistence and recreational catches and discards.
    • Landings for FMFO are estimated as catch input, not product output.
    • The ratio of Direct Human Consumption (DHC) to Fish Meal and Fish Oil (FMFO) production is approximately 5:1.

    End use of marine fisheries landings: variations and factors

    • Data for end-use analysis comes from diverse sources, including official statistics, news reports, company press releases, industry information, historical reports, and scientific articles.
    • Analysis of end-use for 62 countries between 1950 and 2010 reveals three types of fishing countries:
      • Type 1: Countries with dedicated reduction fisheries (e.g., Peru, Denmark)
      • Type 2: Countries where FMFO production is dominated by by-products (e.g., France)
      • Type 3: Countries with no FMFO production from by-products or reduction fisheries (e.g., Iraq, Sudan)
    • Since 2010, significant changes have occurred, transforming many Type 3 countries into Type 1, largely driven by Chinese fishing activities in West Africa.

    Industrial & Artisanal Marine Landings

    • The top ten species used for FMFO constituted roughly 77% of FMFO destined catches, which decreased to approximately 53% by 2010.
    • This implies an increasing diversity of taxa being utilized for FMFO production.
    • More catch from non-top-ten taxa is being diverted to FMFO.
    • Over 90% of catches destined for non-DHC uses are food-grade or prime food-grade fish taxa.
    • Very little catch used for non-DHC uses are industrial-grade fish with no DHC markets.

    Intensive Feed-lot Operations

    • Intensive feed-lot operations (aquaculture, chicken and pig farming) are driving many global fisheries, particularly in developing countries.
    • This raises ethical concerns: Is redirecting food from the poor and food-insecure to the rich and food-secure the best use of fish resources? The situation in West Africa presents a significant equity problem.

    DPIRD – Fisheries

    • DPIRD is responsible for the sustainable management of Western Australia's fish and aquatic resources.
    • This includes all bony fish, sharks, aquatic invertebrates, marine algae, and seagrass.
    • WA's coastline extends 12,800km and presents various challenges due to its size, diverse environments, and oceanic conditions.
    • Three key sectors make up the resource-based fisheries: commercial, aquaculture, and recreational.

    Commercial Fishing

    • 50 commercial fisheries generate $300 million for the WA economy and employ 4,000 people directly and 5,000 indirectly.
    • Key commercial species include:
      • Western rock lobster
      • Australian sardines
      • Prawn
      • Scaly mackerel
      • Scallop
      • Goldband and pink snapper
      • Abalone
      • Spanish mackerel
      • Australian salmon

    Recreational Fishing

    • Around 600,000 people in WA engage in recreational fishing.
    • High community and social value along with economic benefits, exceeding $2 billion in expenditure.
    • Key recreational species include:
      • Blue swimmer crabs
      • Western rock lobster
      • Pink snapper and dhufish
      • Squid
      • School whiting
      • Black bream
      • Herring
      • Silver Trevally

    Aquaculture

    • Aquaculture provides food, non-edible products like pearls, restocking, and aquarium specimens.
    • Key aquaculture species:
      • Barramundi
      • Mussels/oysters
      • Abalone
      • Marron
      • Trout

    Fisheries Management

    • Commercial fisheries are managed through formal management plans.
    • Recreational fishing is regulated through specific rules and regulations.
    • Ten fisheries hold MSC accreditation.
    • Harvest strategies, stock assessments, and data collection are used to guide sustainable management.

    Harvest Strategy – Ecological Objective

    • Spawning biomass is a key indicator for fish stock health.
    • Target level: 40%
    • Threshold (BMSY): 30%
    • Limit: 20%
    • Harvest control rules (HCR) are implemented when spawning biomass falls below the threshold, aiming to rebuild stocks to above the threshold within a generation.

    Multi-Species Fisheries

    • Indicator species approach is used to assess overall fish health in multi-species fisheries.
    • Data from catch, age structure, environmental factors, and technology are utilized to gather evidence.

    Challenges and Future Directions

    • Population growth and coastal development pose significant threats to fisheries.
    • Technological advancements can both benefit and challenge management.
    • Climate change and variability impact fish stocks and ecosystems.
    • Certification (e.g., MSC) and WTO regulations influence trade and sustainability.
    • Loss of access to fishing areas due to marine parks creates challenges for industry.
    • Maintaining social license is crucial for successful management.

    The Global Challenge of Malnutrition

    • One in three people worldwide suffers from malnutrition.
    • Malnutrition is an imbalance, lack, or excess of nutrient intake.
    • There are two main types of malnutrition: undernutrition and overweight/obesity.
    • Undernutrition affects approximately 815 million people globally, leading to 3 million childhood deaths related to malnutrition yearly.
    • Overweight and obesity affect approximately 1.9 billion adults and 41 million children under five years old globally.

    Essential Nutrients

    • Essential nutrients are crucial for human health.
    • There are various essential nutrients, including protein, iron, zinc, and omega-3 fatty acids.

    Fish as a Commodity

    • The global fish trade generates approximately $125 billion annually.
    • Over 60 million tonnes of seafood are exported worldwide.
    • Fish is a significant food commodity, with an average annual catch of 105 million tonnes.

    Fish as a Food Source

    • Fish is a significant source of essential nutrients like protein, omega-3 fatty acids, iron, and zinc.

    Nutritional Dependence on Seafood

    • Seafood plays a critical role in providing essential nutrients for human health; especially in coastal communities.
    • The global demand for seafood is increasing, putting pressure on fish stocks.

    Threats to Fisheries

    • Climate change, pollution, and overfishing threaten the ability of fishing to support nutrient security.
    • Climate change impacts the availability of micronutrients in fish, thus impacting human nutrition.
    • Global seafood consumption is increasing.
    • Seafood consumption varies significantly by region.
    • The proportion of seafood in the diet varies widely across populations.

    Seafood Contributions to Nutrition

    • Seafood provides essential nutrients like protein, vitamin D, omega-3 fatty acids, and zinc.
    • Seafood can contribute up to 100% of the recommended daily intake for certain nutrients, such as vitamin D and omega-3 fatty acids.

    Environmental Impacts of Animal Foods

    • Animal food production, including fisheries, has significant environmental impacts:
      • Greenhouse gas emissions
      • Acidification of water bodies
      • Eutrophication

    Risks and Challenges

    • Overfishing and unsustainable fishing practices threaten the long-term sustainability of fisheries.
    • Pollution and climate change impact the health and safety of seafood.

    Nutritional Diversity of Fish

    • Different fish species provide varying levels of different nutrients.
    • Fish species from tropical regions are rich in calcium, iron, and zinc.
    • Fish from cold regions are high in omega-3 fatty acids.
    • Smaller fish species contain higher levels of calcium, iron, and omega-3 fatty acids.
    • Pelagic feeding fish have higher concentrations of omega-3 fatty acids.

    Nutritional Databases

    • Several databases and tools help track and analyze the nutritional content of fish:
      • FishBase Nutrient Tool: Provides information on the nutrient composition of different fish species.
      • Aquatic Food Composition Database (AFCD): Offers comprehensive data on the nutritional content of aquatic foods.

    Importance of Biodiversity

    • Biodiversity in fisheries enhances the diversity of nutrients individuals can obtain from consuming seafood.
    • Maintaining biodiversity is vital for ensuring the long-term sustainability and nutritional value of fisheries.

    Contribution of Small-Scale Fisheries

    • Small-scale fisheries play a significant role in providing essential nutrients to local populations.
    • Small-scale fisheries often target a variety of fish species, providing a wider range of nutrients.

    Managing Fisheries for Maximum Nutrient Yield

    • Managing fisheries for maximum nutrient yield is crucial for ensuring long-term food security and human wellbeing.
    • This approach prioritizes the sustainable harvesting of fish that provide the highest levels of essential nutrients for human health.

    Accelerometers

    • Accelerometers are devices that measure movement and can be used to study animal behavior.
    • They are often used in conjunction with other tagging methods, such as animal-borne cameras.

    Intrauterine Tagging

    • Intrauterine tagging is a new method for tracking sharks that involves implanting a satellite transmitter into a pregnant female shark.
    • The transmitter can be used to track the shark's movements and identify when it gives birth.

    Shark Conservation

    • Shark populations are declining globally due to fishing.
    • The Indian Ocean has many countries with critical conservation challenges but also great conservation potential.
    • Conservation approaches, such as fishing restrictions and marine protected area design, depend on the context and location.

    Seychelles Shark Populations

    • Seychelles has a long history of shark fishing.
    • The total reconstructed domestic catch was ~ 1.5 times larger than the baseline reported by the (FAO).
    • Domestic catches (excluding large-scale industrial pelagic catches) increased by over 500% throughout the time period.

    Shark Fishing in Seychelles

    • Only 2 small vessels currently target sharks (Berke and Nevill, pers.comm.).

    Tagging Methods

    • Tagging sharks can help identify areas of conservation importance and overlap with fishing areas.
    • Tagging can be done in conjunction with other data collection methods, such as DNA sampling, fecal or oral DNA sampling, and maturity assessments.
    • PIT tagging, a method for identifying individual animals, is often done in conjunction with other tagging methods.

    Acoustic Tagging

    • Acoustic tagging allows researchers to track the movements of sharks within a specific area.
    • Acoustic tags emit signals that are detected by stationary receivers positioned in the water.

    Satellite Tagging

    • Satellite tagging helps researchers understand the long-distance movements of sharks.
    • Satellite tags can be used for a variety of species and environments.
    • Pop-up satellite archival transmitting (PSAT) tags are a type of satellite tag that provides data on a shark's diving behavior, temperature exposure, and other environmental factors.

    Recreational Boat Ramp Survey

    • Provides a preliminary description of recreational fishing activity within and near the wind farm area.
    • Includes a pre-survey desktop assessment and consultation with fishers and peak bodies followed by a survey at select boat ramps across a five-day period of recreational fishing activity.

    Other Data Sources

    • Includes data from fisheries-dependent sources such as gillnets and Danish seines.
    • Aerial surveys provide information on surface schools, fish, and fishing activity in the area.
    • Data from fisher interviews is included.
    • Data from the CSIRO SEA-MES study of 2023/26.

    Minimizing Impacts

    • Impacts on fish include reducing noise emissions from piling. This can be done by using bubble curtains that require noise emission modelling.
    • Burying the cable to reduce EMF can also minimize impacts.
    • Construction activities should be minimized during the spawning period.
    • Impacts on fishers include minimizing impacts on their target species, Good communication so they can plan their fishing activities, not locking the area up, and providing alternative work opportunities or compensation.

    Impacts to Fish

    • The susceptibility of various fish species to wind farm activities and infrastructure varies.
    • Species that are site-attached and species with swim bladders are likely to be most impacted by noise emissions.
    • Species that prefer sediment-based habitats may be most impacted by habitat change resulting from the installation of project infrastructure.
    • Site-attached and benthic sharks, rays, and invertebrates may be most impacted by electromagnetic interference from transmission cables.
    • Species targeted by commercial and recreational fishers may be most impacted by changes in fishing activity.

    Learning About the Existing Environment: Review of Fisheries Data

    • The first step is to identify which fisheries are legally able to fish in the area of the proposed wind farm.
    • Then identify which of these actually do fish in the area.

    Learning About the Existing Environment: Baseline Surveys of Fish

    • The key data to meet objectives are:
      • Species presence
      • Spatial pattern (vertical and horizontal plane)
      • Temporal pattern
      • Proxy for abundance
    • Priority species are included as well as indicator species and groups.
    • Species diversity is also assessed.
    • This data is combined with relevant ecological, biological, and other literature to provide a more complete picture of species distribution, spawning, migration season, and stock/population areas.

    Fish

    • Includes many species.
    • There are seasonal and spatial differences in abundance.
    • Diverse ecology and biology are present.
    • Diverse use of the wind farm area is exhibited.
    • Various targeted by fishers or bycatch.
    • Various protected under state or Commonwealth legislation.
    • Some species include species specific stock rebuilding strategies and recovery plans.
    • International considerations are included such as the UN Convention on Biological Diversity and the IUCN Red List of Threatened Species.
    • Species of potential cultural importance.
    • Species of concern to other stakeholders eg Victorian National Parks Association.

    Choice of Survey Method and Design

    • Considerations include:
      • Overseas experience
      • Australian context
        • NESP Field Manuals for Marine Sampling in Australian Waters
        • Liaison with SMEs (eg white shark monitoring)
        • Information from fishers
        • Previous experience

    Benthic Stereo Baited Remote Underwater Video (SBRUV)

    • This method is used to provide a baseline description of the demersal fish resource present during summer and winter 2024 within and near the wind farm area.
    • Each survey included 130 sites in 12 days across the ‘fish study area’ of approximately 700 km2, which includes the wind farm area with a 5 km buffer.
    • Data includes seasonal, depth, and habitat-structured analysis of species presence and relative abundance, as well as species richness.
    • Additional data includes temperature and light intensity.
    • The survey was informed by interviews with commercial fishers.
    • The broad range of species means results can be compared with future monitoring.

    Environmental DNA (eDNA)

    • This method provides baseline evidence of fish presence, including rare or cryptic species of conservation importance. It was conducted in summer and winter within and near the wind farm area.
    • Each survey included the same scope as the SBRUV.
    • Seawater used for analysis was collected before the deployment of the SBRUVs.
    • There is expected variation in eDNA concentrations, therefore multiple samples were collected in the area of interest.
    • The broad range of species means results can be compared with future monitoring.

    Passive acoustic monitoring of tagged white sharks

    • This method provides a description of the seasonal presence, number, and movement patterns of acoustically tagged white sharks in the area.
    • Acoustic receivers were deployed for a minimum of two summers between October 2023 – April/May 2025.
    • Data includes arrival time, residence time, and characteristics of detected sharks, including the relationship between sex, age class, depth strata, and water temperature.
    • This method was informed by interviews with commercial fishers.
    • Results can be compared with future monitoring.

    Integrated Pelagic Baited Remote Underwater Video (PBRUV) and echo sounder

    • This method provides a baseline description of the pelagic fish resource present in summer within and near the wind farm area.
    • The survey targeted 40 sites in 10 days across the fish study area, during summer when key pelagic species are expected to be most abundant.
    • Data includes depth, habitat structured description of pelagic fish life including species presence, relative abundance (MaxN), and number of discrete schools.
    • Additional data includes temperature.
    • The method was informed by interviews with commercial fishers.
    • The range of species means results can be compared with future monitoring.

    IUU: Illegal, Unreported, and Unregulated

    • The term "IUU" is problematic because it conflates legality, reporting, and management.
    • "IUU" is commonly used in media and politics but is scientifically inaccurate.
    • Instead of "IUU", use the individual components: "illegal," "unreported," or "unregulated".
    • Define each term clearly when using them.
    • Illegal fishing violates the laws of a fishery, including EEZs or high seas fisheries managed by RFMOs (Regional Fisheries Management Organisations).
    • Unreported fishing refers to catches not reported to national authorities or RFMOs.
    • Unregulated fishing involves vessels without nationality, vessels flying the flag of a non-RFMO member country in high seas fishing or any fishing without reporting or management mandates (open access).

    Distant-Water Fishing (DWF)

    • DWF is defined as fishing outside a country's EEZ on the high seas or in another country's EEZ.
    • Example of DWF: Australian fishing in the Eastern Indian Ocean high seas waters.
    • Example of DWF: Indonesian vessels fishing 400 km offshore from Perth. This can be considered both DWF and IUU, depending on reporting and management regulations.

    Sea Around Us data layers

    • Sea Around Us data layers are used to track fishing activity and provide information on catch amounts, distances, and fishing entities.
    • Data layers help understand different fishing patterns and identify potential areas of IUU fishing.
    • These layers can be used to track DWF activities and their impact on marine ecosystems.

    Drivers of Discarding

    • Discarding behavior is driven by environmental factors, social/political factors, and fishers' choices.
    • Environmental factors: Recruitment of small fish into the fishery.
    • Social/political factors: Quota regulations, choice of fishing gear, and fishers' behavior.

    Types of Discards

    • Discarding is categorized into gear-based, market-driven, regulatory discarding, and other factors.
    • Gear-based discarding is associated with bycatch potential; less-selective gear has higher bycatch potential.
    • Traps, pots, and weirs, as well as handlines, are generally less damaging to catch and facilitate release.
    • Bottom trawls, gill nets, and longlines are highly non-selective and body-damaging, resulting in low survival rates for bycatch.
    • Market-driven discarding is influenced by the market demands and prices for different species.
    • Regulatory discarding may result from quotas, size regulations, catch limits, and other management measures.

    Discarding by Geographic Area

    • In the NW Atlantic, foreign fishing countries dominated early on, succeeded by local fleets (Canada and USA).
    • In the EC Atlantic (West Africa), foreign fleets remain dominant.
    • In the NE Atlantic, the NW Pacific, and WC Pacific, local fishing fleets dominate.
    • Discarding is primarily observed in EEZ waters.

    Discarding by Taxonomic Groups

    • Discards occur across various taxonomic groups, including marketable target species and other non-marketable species.
    • Higher discard prevalence for:
      • Marketable target species due to poor product quality, non-selective fishing practices, small sizes, high-grading, and management/enforcement failures.
      • Marine fishes ‘nei’ (not elsewhere included) due to poor information resolution and data collection.

    Global Discard Estimates

    • Estimates of global discards have varied considerably.
    • Alverson et al. (1994) estimated 27 million tonnes of discards based on 1980s and 1990s data.
    • Kelleher (2005) estimated 6.8 million tonnes based on a subset of "quantitatively complete" studies, representing an 8% discard rate.
    • Zeller and Pauly (2005) argued that the decline in discards estimated by Kelleher (2005) may be misleading, as landings data may not accurately reflect changes in discard rates.
    • Zeller et al (2018) provided a revised global discard estimate of 10.2 million tonnes, highlighting regional and taxonomic differences in discard patterns.

    Bycatch Reduction Devices (BRDs)

    • BRDs are tools designed to reduce bycatch in fishing operations.
    • They help minimize the capture of non-target species, contributing to sustainable fishing practices.
    • BRDs promote the survival of bycatch and minimize environmental damage.

    Debate on Status of World Fisheries

    • Over the last 20+ years, numerous papers in Nature and Science have highlighted a "Global Fisheries Crisis"
    • Myers and Worm (2003): Industrial fisheries have reduced the biomass of large predatory fishes by 80% within 15 years after 1960
    • The debate centers on the extent of the crisis and the most effective solutions.
    • Traditional fisheries management includes restrictive measures like catch limits, gear controls, and effort limitations.
    • Novel approaches are advocated by some, such as the establishment of no-take areas.
    • Hilborn supports the effectiveness of traditional fisheries management, while Pauly emphasizes the need for no-take areas to restore fish populations.

    Status of World Fisheries

    • According to FAO (2016) The State of World Fisheries and Aquaculture, 69% of global fisheries are fully exploited or overfished, while 31% are within biologically sustainable levels.
    • Kleisner, Zeller, Froese and Pauly (2013) developed a catch data derived stock-status plot method using the full time series of catches, providing a global view of stock status.
    • This method shows ~ 58% of global fisheries are overfished, ~33% are fully exploited, and ~9% are developing or rebuilding.
    • FAO-SOFIA results differ significantly from the SSP (Stock-Status Plot) findings.
    • FAO uses a limited number of assessed stocks (445) that account for 80% of global FAO catch data.
    • The differences in perspectives on the status of world fisheries can be attributed to varying experiences and scientific approaches.
    • Hilborn primarily focuses on developed countries with strong scientific and management capacity, while Pauly works extensively in developing countries with limited resources, focusing on developing simple and practical approaches for fisheries management.

    Worm, Hilborn et al.(2009) - Rebuilding Global Fisheries

    • A joint working group of Hilborn and Worm with 19 others aimed to find common ground on the status of world fisheries.
    • The group concluded that exploitation rates are declining in some ecosystems studied, but 63% of assessed fish stocks require rebuilding.
    • The study relies on 66 "case studies", with 59 from developed countries and only 7 from developing countries, creating a "case study" bias.

    Russell's Axiom

    • Russell's axiom describes stock size changes over time
    • Formula: S2 = S1 + (R + G) - (M + C)
      • S2 = stock size next year
      • S1 = stock size this year
      • R = recruitment
      • G = growth
      • M = natural mortality
      • C = catch
    • Axiom assumes:
      • No immigration or emigration
      • No habitat degradation or changes to environment or ecosystem

    Density-Dependence of Recruitment

    • Recruitment (R) is affected by stock size
      • Increases initially as the stock size decreases (less cannibalism of new recruits)
      • Decreases as the stock is further thinned (fish face difficulties finding mates and producing recruits)

    Growth and Natural Mortality

    • Growth (G) increases as stock size decreases
      • Less competition for resources allows individual fish to grow faster
    • Natural mortality (M) decreases as stock size decreases
      • Less cannibalism and other density-dependent mortality factors

    The Logistic Population Growth Curve

    • A model used in fisheries science
    • Describes the relationship between population growth and carrying capacity (K)
    • Considers factors like:
      • Natural mortality (M)
      • Competition for resources
      • Fecundity
      • Individual growth

    Sustainable Catch and Surplus Production

    • Sustainable catch is the amount of fish that can be harvested without depleting the stock
    • Surplus production refers to the extra productivity generated by fishing, which can be sustainably harvested
    • Surplus production is maximized at an intermediate stock size

    Key Contributions to Fisheries Science

    • Russell's axiom provides a simple and elegant model for understanding fish population dynamics
    • The concept of surplus production is central to modern fisheries science
    • Understanding the impact of fishing on recruitment, growth, natural mortality, and stock size is crucial for sustainable management.
    • Most fisheries biologists must measure or estimate various factors like stock size, recruitment, growth, natural mortality, and catch to advise fisheries managers on sustainable levels of fish catch.

    Fishing sector definitions

    • Definitions of fishing sectors vary globally.
    • The ‘Sea Around Us’ project defines and categorizes fishing sectors with specific criteria for each.
    • FAO, the Food and Agriculture Organization of the United Nations, has inconsistent definitions of fishing sectors in its publications, using terms like ‘commercial’, ‘subsistence’, ‘industrial’, ‘artisanal’, ‘large-scale’, and ‘small-scale’
    • FAO data on fishing sector catches is not presented by sector.
    • Australia defines the fishing sectors as: ‘Commercial’, ‘Traditional’, and ‘Recreational’.
    • Globally, many countries and organizations distinguish between ‘Large-scale’ (commercial) and ‘Small-scale’ (commercial and/or non-commercial) fisheries.
    • The differentiation between ‘Large-scale’ and ‘Small-scale’ sectors is often made based on the length of the vessel, with boundary differences between countries and organizations.

    Sea Around Us project definitions

    • The Sea Around Us project defines ‘Industrial’ fishing sector as: "All fishing gears that are dragged or towed across the seafloor or intensively through the water column using engine power (e.g., bottom- and mid-water trawls) are considered industrial…Irrespective of vessel size."
    • "All fishing in foreign waters, irrespective of vessel size or gear type." is considered industrial.
    • The ‘Sea Around Us project defines ‘Artisanal, subsistence and recreational’ sectors as: "Small-scale fisheries (SSF) are assumed to operate only in domestic waters (i.e., in their own country’s EEZ). Within their EEZ, they are further limited to the Inshore Fishing Area (IFA) within each EEZ, to a maximum of 50 km from the coast or to 200 m water depth, whichever comes first. IFA definition assumes the existence of small-scale fisheries, and thus unpopulated islands have no IFA."

    Sea Around Us project definitions - differences with other organizations

    • The Sea Around Us project’s definitions differ from other organizations which often include ‘baby-trawlers’ in the ‘small-scale’ sector. This is the main reason why their estimates of small-scale catches are likely higher in other reports.

    Fishing Access Database

    • This database tracks which countries fish in which foreign EEZs, as well as when and what they are fishing.
    • Data is comprised of access agreements and observed access.
    • Database currently contains 7,600 entries including 1,800 agreements and 5,700 observed access points.

    Spatial Allocation of Catch Data

    • Catch data is allocated spatially in ecologically meaningful and politically feasible spaces, using a GIS Ocean data layer at ½ degree Lat/Long.

    Sea Around Us

    • The Sea Around Us is an international research partnership focusing on global fisheries and their impacts on the marine environment.
    • Founded in 1999 at the University of British Columbia, the initiative aims to assess fisheries impacts on marine ecosystems and offer policy solutions.
    • The Sea Around Us utilizes existing data and generates new data to fill identified data gaps.

    Objectives of the Sea Around Us

    • Assess the impacts of fisheries on marine ecosystems worldwide.
    • Develop mitigating strategic policy solutions for a range of stakeholders, including conservation organizations and civil society.
    • Promote sustainability in fisheries.

    Team

    • The Sea Around Us team comprises an internationally diverse group, including researchers, ecologists, economists, and social scientists.

    Focus

    • The initiative focuses on big-picture and big-data science in fisheries, examining global patterns and trends.

    Data Context

    • The Sea Around Us focuses on global fisheries data, including catch volume and value, fishing effort, stock assessments, and other fisheries parameters.

    Importance of the Sea Around Us

    • The Sea Around Us is a government-independent scientific initiative focusing on global fisheries data.
    • It acts as a global reference point for fisheries data, promoting transparency, and encouraging collaboration across institutions.

    Fisheries Science

    • Tactical Level:
      • Focuses on local scales and single species assessments.
      • Explores basic fish biology, such as age, growth, and reproduction.
      • Conducts stock assessments to inform local management decisions.
    • Strategic Level:
      • Recognizes the interconnectedness of global fisheries as a highly traded food commodity.
      • Assembles local level knowledge to provide a "bigger picture" view of fisheries.
      • Employs big-data science to analyze global trends and patterns.
    • Most fisheries science focuses on the tactical level.
    • The Sea Around Us provides a strategic level framework for understanding global fisheries.

    Fish Aggregation Devices (FADs)

    • Increased fishing power
    • Higher catchability
    • Concentrates fish

    Destructive Fishing

    • Dynamite fishing
      • Widespread in tropical countries
      • Illegal
      • Easy to make
    • Cyanide fishing
      • Easy way to catch fish alive
      • Dominates aquarium and live food fish trade
      • Widespread in tropical countries

    Bottom Trawling

    • The most destructive fishing gear globally
    • Active bottom contact gear
    • High seafloor disturbance

    Types of Trawls

    • Otter Trawls: uses heavy otter boards, faster-moving finfish.
    • Beam Trawls: metal beam keeps the net open, targets flatfish and slow moving species.
    • Pelagic or mid-water trawls: may have otter boards, weights or use net shape, single or paired vessels, targets small & medium sized pelagic species.

    Dredges

    • Very heavy seafloor gear
    • Targets sessile invertebrates (scallops and oysters)
    • High seafloor disturbance

    Purse Seine Nets

    • Encircle or surround fish schools
    • Mainly pelagic, but also beach purse seines
    • Major tuna fishing gear
    • Can be extremely large

    Active versus Passive Fishing

    • Passive fishing: Fishing action occurs independently of vessel movement, although setting the gear may require vessel movement and engine power.
    • Active fishing: Fishing action requires vessel movement and engine power (e.g., trawling, dredging).
    • Traps/pots/weirs: Passive fishing gear that entices or guides animals into being caught, baited or unbaited.
    • Weirs: Widely spread fishing method before industrialization.

    Hadrah Weirs

    • Used extensively in the Persian Gulf
    • Catch is often unreported
    • Google Earth and Google Earth archive can be used to estimate their use

    Western Rock Lobster Managed Fishery (WCRLMF)

    • The WCRLMF is located on the west coast of Australia
    • Panulirus cygnus is the scientific name for Western rock lobster
    • The WCRLMF is a managed fishery and has been in operation since 1897
    • A limited entry system was implemented in 1963.
    • Input controls were implemented until 2009/2010, using pot numbers as a measure of effort
    • The fishery was certified by the Marine Stewardship Council (MSC) in 2000
    • The catch and effort levels were high in the past, with catches of approximately 11,000 tonnes and 10 million pot lifts.

    Management Shifts & Outcomes

    • In 2009/2010, input controls were shifted to output controls due to “recruitment failure”
    • The total allowable catch (TAC) was introduced alongside individual transferable quotas (ITQs)
    • By 2009/2010, fishing effort was reduced by 73%
    • Despite a reduction in catch (less catch), the catch per pot lift increased
    • The overall biomass increased
    • Increased profit was recorded in 2009/2010 (49million)comparedto2008/2009(49 million) compared to 2008/2009 (49million)comparedto2008/2009(13 million)
    • The new harvest strategy focused on targeting Maximum Economic Yield (MEY)

    MEY, EBFM and Triple Bottom Line

    • The MEY is now targeted at 0.35-0.4, compared to the previous target range of 0.7-0.8
    • Benefits of the MEY approach include year-round fishing and removal of some fishing restrictions.
    • The Triple Bottom Line approach seeks to define success by considering ecological, economic, and social factors
    • Benefits of managing around the MEY target include increased biomass, reduced fishing effort, and a better work-life balance for fishing crews.
    • Some negative impacts include a reduction in employment opportunities and potential lower profits for local fishermen.

    Management Today

    • Robust stock assessment models indicate the western rock lobster stock is highly sustainable
    • In the last ten years, the total allowable catch (TACC) has ranged from 6,000 – 6,600 tonnes, despite models suggesting 8,000 tonnes would be sustainable
    • The harvest rate currently sits at around 30%, despite the MEY suggesting 35-40%.
    • A model for the WRL MEY is available: https://lobsterapp.shinyapps.io/WRL_MEY/

    The Future of WCRLMF

    • Social licence to operate is a key concern, particularly regarding interactions with whales and other marine life
    • The new harvest strategy will target 0.39 of the MEY
    • Continued puerulus monitoring is crucial
    • Climate change impacts must be carefully considered

    TEPS

    • TEPS (Threatened and Endangered Pinniped Species) refers to the interaction between the fishery and marine mammals
    • Australian Sea Lion (ASL) pups are susceptible to drowning within fishing pots
    • **SLEDs **(Sea Lion Exclusion Devices) have been implemented to protect the ASL pups
    • Two types of SLEDs were tested:
      • SLED A (95-100% exclusion) had no impact on catch rates or mean catch length
      • SLED B (100% exclusion) resulted in a 14% reduction in catch rates (P>0.05), but no impact on mean catch length
    • The length of the fishing season has been adjusted over time in response to whale interactions, ultimately culminating in a year-round season
    • Gear modifications have been implemented to reduce whale entanglements and include rope length restrictions, float limitations, and maximum pull period requirements.
    • Studies show a 64% reduction in whale entanglements (How et al., 2020)

    Other

    • Ongoing research is necessary to understand lobster foraging behaviour
    • The Western Rock Lobster Ecology website (www.panuliruscygnus.org) provides further information
    • Effective fisheries management requires collaboration and expertise from various fields, including fisheries science, biology, oceanography, economics, and politics
    • Managing fisheries ultimately means managing people.

    Compensation and Depensation

    • Compensation occurs when the number of recruits per spawner decreases as stock size increases.
    • Depensation occurs when recruits per spawner increase as spawning stock size increases. This can happen due to predator saturation.

    Stock Recruitment Models

    • Beverton and Holt model displays a linear relationship between stock size and recruitment.
    • Ricker model exhibits a hump-shaped relationship, with peak recruitment at an intermediate stock size.
    • Shepherd model shows a sigmoid relationship, with a gradual increase in recruitment followed by a plateau.
    • These models are average relationships with high variations.

    Surplus Production

    • Surplus production refers to the amount of biomass a population can produce over its natural mortality rate.
    • Carrying capacity (B0) is the maximum sustainable population size where production equals mortality.
    • Fishing can reduce biomass below carrying capacity.
    • Stocks attempt to return to their carrying capacity when fishing stops.

    Basics of Stock Assessment

    • Sustainability in fisheries aims to maintain stocks at a certain biomass level to allow for constant catch levels.
    • Stock assessment involves understanding the stock's condition and the impact of fishing on it.

    Basic Steps of Stock Assessment

    • Unit stock definition: Identifying a self-contained breeding population.
    • Catch data collection: Gathering information on total catches from the fishery.
    • Effort data collection: Recording information about fishing effort, such as fishing days or gear types.
    • CPUE (catch per unit of effort) calculation: Combining catch and effort data to derive a time series of CPUE.
    • Biological characteristic data collection: Gathering data on growth, mortality, stock size, and recruitment relationships.
    • Yield estimation: Deriving expected catch levels under different fishing pressure conditions.
    • Management advice: Providing recommendations to fishery managers based on assessment results.

    Unit Stock

    • Defining unit stocks is often difficult due to the extensive ranges and dispersive larval stages of fish.
    • Unit stocks are often identified based on spawning grounds and geographic limitations.
    • Genomics can aid in assessing mixing between populations.
    • Unit stock identification is often done after the fishery has already developed.

    Empirical Derivations

    • Natural mortality rates (M) are difficult to measure directly.
    • Indirect methods, such as catch curves, are often used to estimate mortality rates.
    • Stock assessment models frequently assume a specific mortality rate.

    Stock Size

    • Estimating stock size is a crucial and challenging task.
    • Two approaches are used:
      • Surveys estimate absolute stock size (number and biomass).
      • Indices (e.g., CPUE) provide relative comparisons.
    • Various methods for estimating stock size exist, all with inherent uncertainties.

    Stock Recruitment

    • Stock recruitment is the relationship between spawning stock size and the number of recruits entering the population.
    • Predicting recruitment based on spawning stock size is challenging due to factors like density-independent mortality, environmental variability, and complex relationships between stocks and recruits.
    • Stock-recruitment data often display high variability and lack a clear relationship.

    Growth

    • The von Bertalanffy Growth Function (VBGF) is a common model for describing growth in fish
    • The VBGF formula: Lt = Linf * (1 - e ^ (-K * (t - t0)))
      • Lt = length at age t
      • Linf = asymptotic length (maximum length the fish would reach if it lived forever)
      • K = growth coefficient or curvature parameter, the rate at which the curve approaches Linf
      • e = the base of natural logarithms
      • t0 = age at which length is zero if the fish had grown in the manner described by the VBGF for the available size at age data. t0 is negative.

    Mortality

    • Mortality is often described as exponential decay, with younger fish dying at a higher rate than older fish
    • Formula for exponential decay: Nt = N0 * e ^ (-Z * t)
      • N0 = the initial number of animals
      • Nt = the number of animals remaining at time t
      • e = the base of natural logarithms
      • Z = the exponential rate of total mortality

    Fisheries Mortality

    • Three types of mortality are recognized in fisheries:
      • Z = total mortality
      • M = natural mortality
      • F = fishing mortality
    • Total mortality (Z) is the sum of natural mortality (M) and fishing mortality (F): Z = M + F
    • Fisheries biologists try to estimate Z and separate it into its components, M and F.

    Estimating Mortality Rates

    • Various methods are used to estimate mortality rates, with varying degrees of accuracy:
    • Survival rate estimates
    • Mark-recapture methods (tagging)
    • Age- or length-based catch curves
    • Empirical derivations
    • Directly measuring natural mortality rates (M) is difficult, so indirect methods, especially catch curves, are more common.
    • Many stock assessment models assume a value for M.

    Stock Size

    • Two approaches are used to estimate stock size, which is a challenging task in fisheries:
    • Absolute stock size estimation (number, biomass) through surveys. This is costly and has limitations in spatial and temporal coverage, but can provide valuable insights.
    • Index of stock density estimation (e.g., catch per unit effort) for temporal or spatial comparisons.
    • Various methods are used to estimate stock size, all with uncertainty:
    • Mark recapture
    • Areas fished by gears
    • Depletion experiments
    • Catch data and fishing mortality estimates
    • Acoustic surveys
    • Egg surveys
    • Direct enumerations
    • Virtual Population Analysis (Cohort Analysis)
    • Catch per unit effort relationships

    ### Stock Recruitment Relationship

    • The relationship between stock size and recruitment is a crucial and often difficult aspect of fisheries assessment.
    • Difficult to predict the number of recruits that will enter the stock based on the spawning stock size due to various factors.
    • Three biological processes influence the stock-recruitment relationship:
      • Density-independent mortality
      • Density-dependent mortality
      • Environmental variability

    Surplus Production

    • Schaefer's model is a simplified representation of the surplus production model, which assumes a relationship between stock size, fishing effort, and the amount of fish that can be harvested sustainably.
    • According to the model, a stock size (Bt) that maximizes sustainable yield (MSY) leads to optimal fishing effort.
    • Overfishing occurs when fishing mortality (F) exceeds the level that supports MSY (FMSY) resulting in a decline in the fish stock.
    • Overfished status refers to a fish stock with a biomass (B) below the level that supports MSY (BMSY).

    Kobe Plots

    • Kobe plots visualize the relationship between stock biomass (B) and fishing mortality (F), showing the status of a fish stock relative to MSY.
    • The plot provides a graphical representation of overfished and overfishing situations.
    • The plot is used to identify areas for management action based on the current status of the fish stock.

    Catch per Unit of Effort (CPUE)

    • The Indian Ocean islands are heavily reliant on small-scale fisheries and have low agricultural output, leading to a high poverty rate.
    • Lack of data reporting and management is prevalent, hindering accurate assessments.
    • The islands boast exceptional biodiversity and endemism, often referred to as the "Galapagos Islands of the Indian Ocean."
    • Large-scale industrial fishing operations, both domestic and foreign, have not been factored into assessments.
    • Tuna fishing activity in offshore waters is likely a significant contributor to the overall catch.

    Catches

    • Following the 1991 Gulf War, Yemen experienced repatriations from Saudi Arabia, contributing to increased migration to the islands.
    • By the early 2000s, unsustainable fishing practices by small-scale fishing fleets led to significant declines in catches.
    • The internal conflicts in Yemen during the 2010s caused a decline in artisanal fishing practices, with many fishermen shifting to subsistence fishing.

    Effort and CPUE

    • Extensive development initiatives from 1960 to 1980 resulted in the motorization of fishing fleets across the islands.
    • In response to diminishing catches, particularly after the year 2000, the number of fishing vessels increased.
    • This led to a rapid decline in CPUE by the mid-2000s, suggesting overfishing or a high risk of overexploitation, corroborated by independent research.

    Fishing Effort and CPUE: Standardization

    • Fishing effort data, often expressed in units like boat-hours or sets, vary widely depending on the specific fishery or gear type.
    • To enable meaningful comparisons across different fisheries, gears, and spatial scales, standardization is crucial.
    • Sea Around Us utilizes standardized kilowatt-days (kWday) as a unit of measurement.

    Sea Around Us - Indian Ocean

    • The Sea Around Us project, focusing on the Indian Ocean region, utilized standardized CPUE data to assess fisheries in Comoros Islands, Madagascar, Mayotte and Mozambique.
    • The analysis considered only small-scale fisheries, excluding those operating in French Mozambique Channel Islands due to their uninhabited status.
    • Large-scale and industrial fishing efforts, domestic and foreign, were not included in this assessment.

    Effort Reconstruction

    • Reconstructing accurate fishing effort data requires extensive research, including thorough searches for, understanding, and interpretation of information.
    • The process involves meticulous vetting of data for applicability and limitations, and documenting all assumptions and caveats.
    • Despite meticulous efforts, 'dirty' data is a persistent issue, necessitating continued vetting and verification.

    Effective Effort

    • Effective effort refers to the actual time or energy invested in fishing, accounting for factors like fishing hours, trip duration, and gear usage.

    Reconstructed Catches

    • Reconstructed catches provide insights into historical fishing activities, complementing ongoing data collection efforts.
    • A significant decline in CPUE, reaching 91%, was recorded across the Indian Ocean islands, declining from 174 kg·kWday-1 in 1950 to 15 kg·kWday-1 by 2016.
    • The widespread motorization of fishing fleets, leading to a substantial increase in the number of vessels, greatly contributed to this decline.
    • Standardization of CPUE data enables comparisons across different fisheries, gear types, countries, regions, and globally in order to understand and manage the broader impact of fishing on marine resources.

    Measuring Fishing Effort

    • Fishing effort is commonly measured at the fleet or gear level, like the Northern Prawn Trawl Fleet (NPTF) in Australia.
    • Nominal effort refers to the number of vessels or units in a fishery (e.g., large vs. small trawlers in NPTF).
    • Effective effort considers the duration of fishing, measured in hours or days fished per year per vessel (e.g., boat-hours trawled per boat per year in NPTF).

    Standardizing Fishing Effort

    • Standardizing effort across diverse fishing gears and fisheries over time is challenging.
    • Traditional metrics like boat-hours, sets, or man-hours are often gear-specific and do not easily translate across different fishing methods.
    • Utilizing standardized units like kilowatt-days (kWday) can help overcome this limitation and allow for more comprehensive comparisons of effort and CPUE across different fisheries and regions.

    The "Real" Catch in the World: Catch Data Reconstruction

    • Catch = Landings + Discards
    • The FAO (Food and Agriculture Organization of the United Nations) is unable to track all fish catches.
    • There are gaps in FAO data, particularly regarding unreported and discarded catch.
    • Catch reconstruction efforts use multiple data sources to create a more accurate picture of global fisheries catches.
    • Catch reconstruction methods are often complex and subtle.

    Defining Fishing Sectors

    • Industrial Sector: Large-scale, motorized vessels, catches sold commercially.
    • Artisanal Sector: Small-scale, catches primarily commercial, with some consumption by crews.
    • Subsistence Sector: Mainly for family/community consumption, often conducted by women and children, non-commercial.
    • Recreational Sector: Primarily for pleasure, some catch may be sold or consumed, non-commercial.

    The Importance of Small-Scale Fisheries

    • Small-scale fisheries are often overlooked but play a crucial role in global fish catch.
    • Conflict often exists between small-scale and industrial fishing sectors.
    • Effective fisheries management should prioritize carefully managed small-scale fisheries and limit industrial subsidies.

    Catch Data Layers in the Sea Around Us Catch Database

    • Three layers of catch data:
      • Layer 1: Reconstructed Domestic Catch: Detailed estimation of reported and unreported catches for a country's own waters.
      • Layer 2: Inferred Foreign Catch: Relying on FAO data for catch recorded in other countries' waters, excludes large pelagic species under Tuna RFMO mandates.
      • Layer 3: Assigned Tuna RFMO Catch: Data from Tuna RFMOs (Regional Fisheries Management Organizations) for large pelagic species, spatial harmonized and with preliminary discards added.

    Whale Protection

    • The Australian government passed the Whale Protection Act in 1978, effectively ending commercial whaling in Australian waters.

    Turtle Protection

    • Commercial export of hawksbill tortoiseshell began in Western Australia in 1869.
    • The green turtle fishing industry operated intermittently between 1870 and 1961 before becoming successfully established in the 1960s.
    • Historical records suggest between 55,125 and 69,000 green turtles were potentially harvested from Western Australian waters before the industry closed in 1973.

    Fishing and Seafood Demand

    • Developed nations face a growing seafood demand while their fisheries and catches are becoming increasingly regulated and declining.
    • This leads to either importing seafood from countries with little bycatch monitoring, or increasing production in other industries like agriculture with their own environmental impacts.

    WA Fisheries Catches

    • Western Australian fisheries catches are relatively small compared to the Western and Central Pacific Fisheries Commission's (WCPFC) reported 2.4 million tonnes of top 4 tuna species.

    Uncertainty and Projections in Science

    • Science uses words like "uncertainty," "projections," "scenarios," "errors," "risk," and "evidence" in specific ways that may differ from their meaning in everyday language.

    Information Scaling for Science Communication

    • Scientific information can be presented at different levels of detail, from detailed theses to concise briefing notes.

    Shark Conservation

    • There are diverse stakeholder groups with varying and sometimes conflicting objectives related to shark conservation.
    • The collective term "sharks" can homogenize a large number of species with different characteristics and values.

    Marine Seismic Surveys

    • Marine seismic surveys are used for oil and gas exploration.
    • They involve emitting sound waves into the ocean floor.

    Whaling in Western Australia

    • Whaling was one of the first viable industries in Western Australia, starting in 1829.
    • The last whaling station in the English-speaking world closed in Western Australia in 1978.

    Challenges of the Modern World

    • The rapid pace of change in the modern world presents challenges for scientific research and decision-making.

    Science and Policy

    • Science and policy operate within different contexts and use different languages.
    • Scientists need to clearly communicate their findings to policymakers.

    Why Choose a Marine Science Career?

    • Reasons for choosing a career in marine science include a passion for the ocean, a desire to protect the environment, and a concern about climate change.

    The Context of Science

    • Science is embedded in cultural, economic, social, and political spheres.
    • This context influences scientific research and decision-making.

    Complexity of the World

    • The world is a complex system of interconnected elements.
    • Multi- and trans-disciplinary approaches are needed to understand and address complex problems.

    Changes in Oxygen Content

    • Warmer water holds less oxygen than colder water
    • Water breathing animals are oxygen constrained, as the oxygen concentration in water is lower and its viscosity is much higher than in air
    • Growth, reproduction, feeding, activity patterns, and behavior of aquatic animals are limited by their ability to obtain oxygen
    • There are more large fish species in temperate areas than in the tropics
    • As water temperatures increase, oxygen levels decrease, resulting in smaller fish sizes
    • Global body weight of fish within a species is expected to shrink by 14-24% due to climate change
    • Tropical and semi-tropical areas are expected to be most affected, with a reduction of over 20% in fish body weight

    Acidification

    • Oceans are predicted to become 150% more acidic by the end of the century
    • Ocean acidification harms oysters, corals, plankton, and shellfish that depend on calcium carbonate (CaCO3) for shell formation
    • Higher acidity dissolves existing shells and hinders new shell growth
    • Zooplankton, a crucial link in food webs, heavily rely on CaCO3
    • Lower pH affects the development of otoliths (ear bones) in fish, crucial for balance, sensory perception, and smell
    • Acidification has wide-ranging impacts throughout the marine food web

    Sea Level Rise

    • Globally, sea levels have risen by over 20 cm since 1880
    • The rate of sea level rise has doubled from 1.4 mm/year to 3.5 mm/year
    • By 2100, sea levels are expected to rise conservatively by 1-2 meters, and potentially by 3-15 meters due to the melting of the West Antarctic ice shelf
    • Storm surges exacerbate the impact of sea level rise

    Changes in Ocean Temperature

    • Studies have shown a shift in species distribution in Western Australia, both latitudinally and in depth
    • Latitudinal shift: 19 km/decade towards higher latitudes
    • Depth shift: 9 m/decade towards deeper waters
    • "Tropicalization" of the Western Australia coast is observed with species gains in the south and losses in the north
    • These changes impact fisheries dynamics

    Impacts on Fisheries

    • Catch potential, considering only temperature changes, shows a large-scale redistribution globally
    • High-latitude regions may experience an increase in catch potential by 30-70%, while tropical regions face a drop of up to 40%
    • This has significant implications for the top 20 fishing nations

    Recent Work on Poleward Shifts in Fishing Vessel Distribution

    • Studies using Vessel Monitoring System (VMS) data show poleward shifts in commercial fishing vessels in the Bering Sea between 2013 and 2022
    • The strongest shifts are observed during winter (October-February), likely due to changes in sea ice conditions and species distribution

    "Gateway to Hell"

    • This refers to a giant methane seep located in the Arctic Ocean, growing at a rapid rate
    • Currently, it's approximately 1 kilometer across and 50-100 meters deep
    • Its growth rate is accelerating, adding more than 900 million liters of methane annually

    Un-extractable Fossil Fuels in a 1.5°C World

    • To have a 50% chance of limiting warming to 1.5°C, significant quantities of fossil fuels must remain unextracted
    • Nearly 60% of oil and fossil methane gas, and 90% of coal must stay in the ground
    • Global oil and gas production needs to decrease by 3% each year until 2050
    • This renders many operational and planned fossil fuel projects unfeasible
    • These estimates are likely an underestimate, as a greater than 50% probability of limiting warming to 1.5°C requires even more carbon to remain unused

    Impacts of Climate Change on Oceans

    • Climate change impacts oceans in various ways, including:
      • Increase in average water temperature
      • Changes in oxygen content
      • Acidification
      • Sea level rise
      • Changes in ocean current regimes
      • Changes in weather patterns and frequencies (cyclones, rainfall, etc.)
    • These changes have significant implications for marine life and ecosystems

    Changes in Ocean Temperature and Biodiversity

    • Sea surface temperatures are not uniformly increasing; some areas are experiencing cooling
    • Most coastal regions are warming, while certain pelagic areas are cooling
    • Model projections predict numerous local extinctions in tropical and semi-enclosed seas by 2050
    • Species invasions are expected to be most intense in the Arctic and Southern Ocean
    • Overall, significant biodiversity turnover is predicted, impacting over 60% of current marine species diversity

    FishBase History and Evolution

    • FishBase was founded by Professors Daniel Pauly and Rainer Froese.
    • The project began with 600 note cards and a focus on providing free and readily accessible information about fish.
    • FishBase strives for equity and open access.
    • The website is a treasure trove of information on fish.

    Understanding FishBase

    • FishBase provides comprehensive information about different fish species, categorized by:
      • Family
      • Country/Island
      • Ecosystem
      • Topic (including diet, growth, gill surface area)

    Standardisation and Predictive Modelling

    • FishBase utilizes a standard formula for weight calculation: "Weight = a∙Lengthb."
    • Fish measurements are converted to "Total Length."
    • Bayesian statistics play a critical role in predictive modeling.

    The Importance of Accuracy

    • FishBase acknowledges the inherent imperfections in data, emphasizing continuous improvement.
    • The platform is designed to adapt and accommodate new information, eliminating outdated or "zombie" data.

    Dynamic and Updated Database

    • FishBase is constantly updated via deep-linking to other databases (e.g., RedList).
    • New species information is continuously added.
    • Taxonomy information is regularly updated.

    Applications of FishBase

    • The platform offers a wealth of data on various fish species.
    • It enables researchers to analyze and visualize fish data, revealing insights into:
      • Species richness
      • Total abundance
      • Total biomass

    Tips for Effective Use of FishBase

    • Accessing the German version (Fishbase.de) is often faster than the standard version (Fishbase.org).
    • The platform can be leveraged with programming languages like R for data extraction.
    • Explore relevant sections like Aquamaps, BRUVS database, and Species matrices.
    • Consider whether your research focuses on single species or assemblages.
    • Apply a "publication test" to ensure the reliability and validity of the data.

    What is a Marine Protected Area (MPA)?

    • Marine Protected Areas (MPAs) encompass a broad spectrum of marine regions designated for safeguarding biodiversity and fostering conservation.
    • Popular terms for these areas include: Marine parks, reserves, and sanctuaries.
    • The core function of MPAs centers around protecting marine biodiversity.
    • They serve as natural experiments to study marine ecosystems undisturbed.
    • Secondary purposes include rebuilding fisheries, enhancing climate resilience, and sequestering "blue carbon," which is the carbon stored in coastal marine habitats.
    • The International Union for the Conservation of Nature (IUCN) categorizes MPAs based on their level of protection and exploitation.
    • IUCN categories I and II represent the most stringent levels, prohibiting access and exploitation.
    • Categories III through VI encompass various forms of exploitation and are often referred to as "partial protection."

    Why are MPAs needed?

    • MPAs are crucial for addressing the alarming declines in marine wildlife populations, including:
      • 25% reduction in Striped marlin abundance.
      • 33% reduction in Yellowfin tuna.
      • 40% reduction in Shortfin mako shark.
      • 63% reduction in Whale shark.
      • 60% reduction in Blue shark.
      • 89% reduction in Hammerhead shark.
      • 95% reduction in Turtle populations.

    Fisheries Decline

    • Global fish catches reached their peak in 1996, indicating a sustained decline in fishing pressure.
    • Over 33% of global fisheries are categorized as unsustainable, signifying a concerning trend in fish stocks.
    • A decline of 694,000 kg per year in global fish catches was recorded between 1996 and 2018, highlighting the pressing need for conservation efforts.
    • The decline in global fish catches has resulted in tens of billions of dollars lost to national economies.

    No Escape for Marine Life

    • Increased fishing pressure has eradicated a significant portion of marine life from traditional refuges.
    • The impact of fishing intensification is evident in the decline of fish populations, which are increasingly squeezed into smaller, less hospitable spaces.

    The Australian Seascape

    • The Australian marine environment has also suffered considerable losses, with a staggering 30% reduction in large fish populations within a decade.
    • More than 20% of fish populations managed by the Australian government are categorized as overfished or facing overfishing risks.
    • A significant decline in Queensland shark populations has been reported, with losses ranging between 74% and 92% over five decades.

    Warming Oceans

    • Climate change is causing oceans to warm at unprecedented rates, creating significant challenges for marine ecosystems and their inhabitants.

    Industrialization and Marine Ecosystems

    • Extensive oil and gas activities have led to significant disturbances in marine environments.
    • These include seismic surveys, platforms, vessel noise, and oil spills.
    • These disturbances pose a risk to marine species and habitats, disrupting natural processes and causing ecological damage.

    Coastal Evidence of MPA Effectiveness

    • No-take marine protected areas have demonstrated significant ecological benefits, with increases in:
      • Biodiversity (166% increase in numbers)
      • Biomass (466% increase)
      • Size of fish (28% increase)
    • No-take MPAs are linked to increased revenue in fisheries outside their boundaries.
    • They serve as sources of larvae that replenish fish stocks in surrounding areas.
    • The presence of no-take MPAs also contributes to higher abundance of commercially valuable fish species in adjacent regions.

    Resilience of Marine Ecosystems in MPAs

    • Marine protected areas have shown remarkable resilience and recovery from environmental disturbances.
    • They have demonstrated the ability to rebound from coral bleaching events.
    • No-take MPAs are linked to lower occurrences of crown-of-thorns starfish outbreaks and coral diseases.

    Carbon Sequestration in MPAs

    • Marine protected areas play a critical role in sequestering atmospheric carbon dioxide.
    • These areas contribute significantly to mitigating climate change by removing and storing carbon from the atmosphere.

    The Rise of Very Large Marine Protected Areas

    • A growing movement advocates for the establishment of vast marine protected areas, often termed "30 by 30".
    • The 30 by 30 goal aims to protect 30% of global oceans by 2030.
    • Increased efforts are being made to secure protection for the high seas, which represent a significant portion of the Earth's oceans and are largely unregulated.
    • These efforts aim to safeguard the rich biodiversity and ecosystem services of the high seas.

    The Expectation of Increased Research on MPAs

    • There is a rising expectation that researchers will play an increasingly vital role in studying and understanding the effectiveness of marine protected areas.
    • This expectation reflects the growing recognition of the vital role that MPAs play in marine conservation.

    The Evidence of Increased Research on MPAs

    • The number of publications on marine protected areas has seen a significant increase in recent years, demonstrating a growing body of research on the topic.
    • This increased research activity highlights the rising recognition within the scientific community of the importance of MPAs.

    Nile Tilapia's Impact

    • The introduction of Nile tilapia in Lake Victoria led to the extinction of two endemic species: Victoria tilapia (Oreochromis variabilis) and Singida tilapia (Oreochromis esculentus).
    • This happened through competitive replacement, where Nile tilapia outcompeted the native species for resources.

    Trout and Climate Change

    • Rainbow and Brown Trout were introduced in Mt Kenya.
    • Trout populations have declined since 2008 due to climate change and pollution.
    • Warmer temperatures have reduced oxygen levels in the water, making it harder for trout to survive.
    • Pollution from farms has increased fish pests and diseases.
    • Trout has transitioned from a pest to a victim of climate change and pollution, becoming an important indicator species for ecosystem health.

    Tana River Delta

    • The Tana River Delta is a flood-dependent ecosystem.
    • Floods are crucial for maintaining the delta's health.
    • The delta's mangroves are important fish breeding sites.
    • Mangroves are facing degradation due to inadequate freshwater flows and sea water intrusion caused by climate change.
    • Seawater intrusion impacts fisheries and livelihoods.
    • The Tana River Delta is designated as a Ramsar Site, signifying its importance for international conservation.

    Kenya Freshwater Fisheries

    • Kenya heavily relies on freshwater fisheries for food security.
    • Lake Victoria, the second largest lake in the world, is a key source of fish for Kenya.
    • Lake Victoria historically had high diversity of endemic cichlid species.
    • The introduction of Nile perch and Nile tilapia had drastic impacts on native fish populations.
    • Nile perch, introduced in 1954, decimated native species populations.
    • The introduced species changed fishing practices, leading to deforestation and increased pollution.
    • A multi-million dollar Nile perch export fishery developed, but most profits did not benefit local communities.
    • Native cichlids are increasingly used for fishmeal.
    • Data concerns persist regarding the broader impact of these changes on Kenyan freshwater ecosystems.

    Global Capture Production

    • Global capture production consists of 10–12% of freshwater fish
    • Inland fisheries production may be misleading due to improved reporting rather than increased production
    • Many data collection systems for inland waters are unreliable or nonexistent.

    Inland Fisheries Challenges

    • The data for inland fisheries is generally worse than for marine fisheries.
    • Two major reasons for this:
      • Commercial fisheries are generally small-scale, with very few industrial fisheries.
      • Data collection infrastructure is lacking, especially in developing countries.
    • Recreational fisheries, while significant, are largely unreported.

    Importance of Inland Fisheries

    • Inland fisheries are mainly dominated by small-scale sectors:
      • Artisanal and subsistence fisheries in developing countries.
      • Recreational fisheries in developed countries.
    • Underreporting is likely higher than for marine systems.
    • Inland fisheries play a vital role in food and livelihood security for many countries, often exceeding the importance of marine fisheries.

    Underreported Catches

    • Lake Volta (Ghana): Estimated catches are 2-2.6 times higher than reported catches.
    • Thai freshwater catches: Actual catches are estimated to be 5 times higher than reported.
    • Mekong River countries: Actual catches are estimated to be 2.6 MT, compared to 1.6 MT reported.

    Global Catch Estimates

    • Estimated global freshwater catch:
      • 12 MT reported, but the true figure is likely to be higher.
      • 13 MT, excluding non-commercial and subsistence fisheries.
      • 26 MT, including a rough estimate of subsistence fishing.
      • 50-60 MT, assuming a 5x multiplier of reported catches.
      • 93 MT, theoretical maximum based on tropical production rates.

    Aral Sea Example

    • Was formerly the fourth largest lake in the world.
    • It is an endorheic water body, meaning it has no outflow and loses water through evaporation.
    • The Aral Sea began shrinking in the 1960s due to diversions of its rivers for irrigation projects.
    • By the 2010s, the lake had largely dried up.

    Aral Sea Fisheries

    • Significant fisheries existed in the Aral Sea before its contraction.
    • The loss of the Aral Sea has had a devastating impact on fisheries and local communities.

    Combining Marine Science and History

    • Marine science coupled with historical sources can standardize Catch Per Unit Effort (CPUE) over time.
    • Historical data provides biodiversity counts from the past allowing for comparison with present environments.
    • This combined approach helps identify trends and fluctuations in diversity and abundance over time, crucial for understanding the impact of human activity on marine ecosystems.
    • Historical data can be used for hindcasting population sizes, i.e., estimating past population levels.
    • Historical information sheds light on technological advancements in fishing and the evolution of spatial patterns of fishing activity.

    Why Historical Perspective Matters in Marine Conservation

    • Historical information contributes to a deeper understanding of Shifting Baseline Syndrome (SBS).
    • SBS refers to the gradual and imperceptible decline of marine populations where each subsequent generation accepts a lower baseline for what's considered normal.
    • This syndrome highlights limitations of catch statistics, as they often only cover a relatively short period.
    • Incorporating historical data helps identify the scale and extent of ecological change and provides valuable insight for ecosystem restoration strategies.
    • Historical information can be a powerful tool to raise awareness and bolster conservation efforts by demonstrating the magnitude of change.

    Reconstructing Marine Fisheries History

    • The Indo-Pacific region presents challenges in reconstructing marine fisheries history due to its diverse biodiversity, language barriers, and diverse fishing practices ranging from high-value to artisanal/subsistence fishing.
    • However, the region's unique characteristics also offer profound insights into livelihoods and food security.
    • Historical research in the Indo-Pacific requires a multidisciplinary approach, notably incorporating anthropology and ethnography, to leverage oral traditions and augment incomplete written records.

    Historical Insights in Fisheries Science:

    • Historical information plays a crucial role in establishing reference points for stock assessments, particularly in understanding “virgin stock” or “initial biomass.”
    • This is essential for measuring the impact of fishing activities and formulating sustainable management practices.

    Overfishing: A Global Problem

    • Overfishing is a significant threat to marine ecosystems with consequences extending beyond the environment.
    • Billions of people depend on fish for protein, and millions rely on fishing for livelihoods.

    Key Takeaways from Historical Perspective:

    • Understanding the historical context of marine populations is crucial for effective conservation and management.
    • Shifting Baseline Syndrome is a significant concern that must be addressed by incorporating long-term perspectives.
    • Interdisciplinary research is critical for reconstructing and understanding complex marine fisheries histories.
    • History is a valuable tool for shaping more sustainable and informed management strategies in managing marine ecosystems.

    AMSY

    • AMSY uses CPUE data alongside independent prior knowledge about species resilience and stock status estimates
    • CPUE is a proxy for biomass, using the catchability coefficient
    • AMSY provides relatively accurate biomass estimates but yields uncertain exploitation estimates

    LBB

    • LBB relies on length-frequency data, common in tropical regions, to estimate various fish parameters
    • LBB can approximate the current biomass relative to the unexploited biomass
    • This method also estimates a proxy for the relative biomass needed for maximum sustainable yield.

    Biomass Status

    • Only 18% of assessed fish populations are considered healthy based on biomass levels
    • Biomass is deemed healthy when above the level deemed optimal for Maximum Sustainable Yield (MSY)
    • This implies that a majority of populations are not at healthy levels.

    Data-Limited Assessment Methods

    • BSM, CMSY, AMSY, and LBB are commonly used data-limited stock assessment methods.
    • These methods are increasingly used across developed and developing countries.
    • While these methods are not perfect, they are often better alternatives in data-scarce situations.

    Stock Assessment Basics

    • Stock assessment methodologies generally consist of seven steps:
      • Defining the unit stock
      • Collecting catch data from the whole fishery
      • Acquiring effort data from the entire fishery
      • Combining catch and effort data for CPUE time series
      • Gathering data on biological characteristics
      • Deriving estimates of catch under different fishing pressure scenarios
      • Providing stock and catch recommendations to fishery managers.

    Data-Limited Stock Assessment Challenges

    • Data limitations, such as financial constraints, staff shortages, or historical data limitations, present difficulties in implementing comprehensive stock assessment methodologies.
    • Many challenges apply to both developed and developing countries.

    Fishery Research and Development (R&D)

    • Goal: Improve fishing and processing methods, minimize negative impact on fish stocks and marine ecosystems.
    • Methods: Scientific and technological breakthroughs.
    • Sub-categories:
      • Fishery frame surveys
      • Oceanographic studies
      • Fishery socio-economic studies
      • Fishery planning and implementation
      • Creating database and statistical bulletins for fishery management plans

    Maintenance of Marine Protected Areas (MPAs)

    • Cost: Calculated based on MPA size and Human Development Index (HDI) of the country.
    • Balmford et al. (PNAS, 101: 9694-9697): Estimated costs as a function of size and HDI.
    • Beneficial Subsidy: Costs for all MPAs in a country are added and reported as beneficial subsidies to fisheries (up to 15% of ex-vessel value of fish catch).

    Fisher Assistance Programs

    • Goal: Provide temporary support to fishers or ensure income during difficult times.
    • Rationale: Lack of alternative employment opportunities in fishing-dependent regions.
    • Potential Outcomes:
      • Negative: Increased community dependence on government funds.
      • Positive: Reduced fishing pressure through retraining programs.
    • Types:
      • Income support programs
      • Unemployment insurance
      • Worker adjustment programs
      • Fisher retraining

    Vessel Buyback Programs

    • Goal: Reduce fishing capacity and promote resource management.
    • Types:
      • Permit buybacks
      • License retirements
    • Effectiveness: Questioned by Munro and Sumaila (2002, Fish & Fisheries 3: 1-18) and Clark et al. (2005, Journal of Environmental Economics and Management 50: 47-58).

    Rural Fishers' Community Development Programs

    • Goal: Integrated rural fisher development, poverty alleviation, and food security.
    • Methodology: Stakeholder participation within communities and cooperatives.
    • Challenges: Projects focused on productivity enhancement can contribute to overcapacity and have poor management success rates.

    Fisheries Development Projects and Support Services

    • Goal: Support fisheries enterprises and development.
    • Methods: Institutional support, services, bait provision, search and rescue programs.
    • Funding: National sources, bilateral and multilateral assistance programs.

    Fishing Port Construction and Renovation Programs

    • Goal: Provide infrastructure for fishing fleets.
    • Methods: Fish landing site infrastructure, port improvements, harbor maintenance, jetties, landing facilities, and moorage.

    Marketing Support, Processing and Storage Infrastructure Programs

    • Goal: Market intervention, value addition, and price support.
    • Methods: Export promotion, processing and storage facilities, and fish auction facilities.

    Harmful Subsidies

    • Examples:
      • Tax exemptions for fisheries investments.
      • Foreign access agreements.
      • Fuel subsidies.

    Beneficial Subsidies

    • Goal: Ensure responsible management of fisheries resources.
    • Types:
      • Monitoring, control, and surveillance programs.
      • Stock assessment and resource surveys.
      • Fishery habitat enhancement programs.
      • Implementation of MPAs.
      • Stock enhancement programs.

    Global Subsidies

    • Total: US$35 billion per year in public subsidies for the fishing sector.
    • Sumaila et al. (2019) Marine Policy 109: 103695: Estimated that 7% of subsidies were beneficial, 30% were ambiguous, and 63% were harmful.
    • WTO: Attempting to regulate fisheries subsidies to mitigate harmful impacts.

    Human Development Index (HDI)

    • Components: Long and healthy life, knowledge and education, and a decent standard of living.

    China Syndrome

    • Context: China's classification as a developing nation by the UN despite a high HDI.
    • Relevance: Highlights the complexities of economic development and classification.

    Key Concepts

    • Overexploitation: The main driver of fisheries issues around the world.
    • Harmful Subsidies: Subsidies that contribute to overfishing and unsustainable practices.
    • Doha Round of Trade Negotiations (2001-2008): Increased awareness and data on fisheries subsidies.
    • WTO Agreement on Harmful Fisheries Subsidies: Recently agreed to eliminate subsidies for illegal, unreported, and unregulated (IUU) fishing.

    Key Research

    • Sumaila et al. (2024) npj Ocean Sustainability 3(1): 6: Published research on harmful fisheries subsidies.
    • Sumaila et al. (2019) Marine Policy 109: 103695: Researched the economic impacts of fisheries subsidies.
    • Munro and Sumaila (2002, Fish & Fisheries 3: 1-18): Questioned the effectiveness of vessel buyback programs.
    • Clark et al. (2005, Journal of Environmental Economics and Management 50: 47-58): Further questioned the effectiveness of vessel buyback programs.

    Risk-Based Approach

    • The risk-based approach uses two primary levels: consequence levels and likelihood levels
    • Consequence levels assess the potential impact of a particular event on a population
    • Consequence Levels
      • Minor: Impacts are undetectable or have limited effects on population size and dynamics
      • Moderate: Impacts are at the maximum acceptable level of depletion
      • High: Depletion is unacceptable but not affecting recruitment levels
      • Major: Depletion is affecting or likely to affect future recruitment
    • Likelihood Levels
      • Remote: The consequence is unlikely but not impossible
      • Unlikely: The consequence is not likely to occur
      • Possible: The consequence could happen
      • Likely: The consequence is highly probable

    Fisheries Management

    • This framework is used to manage the West Coast Demersal Fishery in Western Australia
    • This fishery is characterized by a diverse range of species including pink snapper and goldband snapper
    • The framework utilizes a statistical catch-at-age model for stock assessment
    • It relies on historical data and standardized CPUE collected since 1990

    Harvest Strategy

    • Formal document outlining the objectives, performance indicators, monitoring and assessment strategy, and harvest decision rules
    • Objectives
      • Ecological Sustainability
      • Economic and Social Benefits
    • Performance Indicators and Reference Points
      • Targets: Identify desired levels of biomass for sustainable management
      • Thresholds: Indicate when management intervention may be needed
      • Limits: Represent critical levels where management action is required
    • Harvest Decision Rules
      • Predefined rules for determining appropriate catch levels based on the current fishery status
      • Help avoid breaching thresholds or limits and assist achieving targets
      • Example: Rebuilding stocks by utilizing a more precautionary approach, such as larger spawning area closures
    • Resource Allocation
      • The harvest strategy also includes plans for resource allocation among various sectors

    Risk Assessment

    • The DPIRD (Department of Primary Industries and Regional Development) uses a comprehensive risk assessment framework
    • The framework accounts for both consequence and likelihood levels to determine potential risks
    • The framework supports ecosystem-based fisheries management (EBFM)
    • EBFM aims to sustain healthy and resilient ecosystems, considering interactions among multiple species

    UNCLOS and UNFSA

    • UNCLOS (1982) gave coastal nations the right to manage fisheries within their Exclusive Economic Zones (EEZs)
    • UNFSA (1995) is an international treaty that set out principles for conserving and sustainably using straddling and highly migratory fish stocks
    • Challenge: managing highly migratory and straddling fish stocks across international waters and EEZs

    Tuna Regional Fisheries Management Organizations (RFMOs)

    • Five major RFMOs exist to conserve and manage tuna
    • 20 of 34 RFMO members face political/industry interference, impacting decisions
    • Tuna RFMOs are responsible for stock assessments
    • Stock assessment: Number of assessed stocks surpasses unassessed stocks
    • Stock Status - Kobe plot: Shows fishing pressure versus relative biomass
    • Catch Reconstruction - Indian Ocean: Recent reports (2000+) suggest 20% more catch than previously reported
    • Gear- & Time-Specific Differences in Reporting - Indian Ocean: Most under-reporting of catches comes from discards, unreported catches, and officially reported catches
    • The Way Forward - High Seas Treaty: Agreement on conserving and sustainably using marine biodiversity in areas beyond national jurisdiction (BBNJ Agreement) adopted in January 2023, Chile is the first ratifier (May 2023)
    • The Way Forward - Marine Protected Areas: 5.3% of the global ocean and 1.2% of the high seas are within MPAs. Implementation of highly/fully protected MPAs within these areas is much less.

    Challenges

    • Mandate vs Non-Mandate Species: More species are classified as non-mandate compared to mandate species.
    • Reporting-Requirements: Reporting requirements for mandate species are more detailed and include by taxon, fishing entity, gear and reporting area (tuna block).
    • Taxonomic Resolution (Especially Elasmobranchs): Data is often reported at higher taxonomic levels (e.g., "shark") rather than family, genus or species levels

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Recreational Fisheries Objectives and Management (Western Australia) - PDF
    Global Marine Recreational Fisheries (BIOL3305) PDF
    Food Security vs Food Supply Lecture PDF
    End Use Of Catches - BIOL3305 Lecture - PDF
    WA Fisheries Management 2024 PDF
    Catching Nutrients: Nutritional Profile of Fisheries - BIOL3305 Lecture - 2024
    Zeller-BIOL-3305-Lec-14-Fassbender-sharks PDF 2024
    Assessing Impacts Of Offshore Wind Farms On Fishers And Fish Catch PDF
    IUU, DWF & Data Layers BIOL3305 PDF
    Bycatch and Discards PDF
    Global Fisheries Status & Crisis PDF
    BIOL3305 Fisheries Science: Foundation and Application PDF
    Fishing Sectors BioL3305 Lecture Notes PDF
    Zeller - BIOL3305 - Lec - 4 - Intro - SeaAroundUs - 2024 PDF
    Fisheries Science: Foundation and Application PDF
    West Coast Rock Lobster Managed Fishery Presentation PDF
    Fisheries Science: Foundation and Application (BIOL3305) - Past Lecture Notes PDF
    Fishing Effort & CPUE: BIOL3305 Lecture Notes (PDF)
    Sea Around Us - Catch Reconstruction (BIOL3305 Lecture 5) PDF
    CSIRO BIOL3305 Talking Science to Policy Makers 2024 PDF
    Climate Change & Fisheries PDF
    FishBase: Diving into the World of Fish - PDF
    Marine Protected Areas and Fisheries (BIOL3305) - 2023 PDF
    Zeller-BIOL3305-Lec-29-Nyingi-Kenya Freshwater PDF
    Freshwater Fisheries Data PDF
    Marine Fisheries in Historical Perspective BIOL3305 PDF
    Data-Limited Stock Assessments (BIOL3305 Lecture) PDF
    Fisheries Economics Lecture Notes PDF
    Fisheries Stock Monitoring in Western Australia (2024) PDF
    Global Fisheries for Tuna and Other Large Pelagic Species PDF

    Description

    This quiz explores the concept of recreational fisheries, their significance in locations such as Western Australia, and the economic impact of recreational fishing. It also highlights research areas such as shark depredation and localized depletion of fish populations.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser