Freshwater Fisheries Data PDF

Freshwater or inland fisheries Dirk Zeller Sea Around Us – Indian Ocean  Status of World Fisheries Trends in global “capture production” 2/28 FAO (2020) The State of World Fisheries and Aquaculture. FAO, Rome. xiii + 206 p. When...

Freshwater or inland fisheries Dirk Zeller Sea Around Us – Indian Ocean  Status of World Fisheries Trends in global “capture production” 2/28 FAO (2020) The State of World Fisheries and Aquaculture. FAO, Rome. xiii + 206 p. When look in more detail at FAO data… Around 10-12% of total global reported “capture production” FAO (2020) The State of World Fisheries and Aquaculture. FAO, Rome. xiii + 206 p. When look in more detail at FAO data… FAO (2020) The State of World Fisheries and Aquaculture. FAO, Rome. xiii + 206 p.  When look in more detail at FAO data… SOFIA: “This continuously rising trend in inland fisheries production may be misleading…” Due to improved reporting and estimation at the country level in recent years rather than due to increased production - ‘presentist bias’ (Zeller & Pauly 2018) Many data collection systems for inland waters are unreliable or non-existent - Complete absence…. “no data” = zero catch FAO (2020) The State of World Fisheries and Aquaculture. FAO, Rome. xiii + 206 p. 5/28 Zeller & Pauly (2018) Marine Policy 90: 14-19  Why would data quality be relatively worse in inland fisheries compared to marine? Two main reasons…. 1. Commercial fisheries all small-scale… no industrial fisheries (2-3 exceptions)  Industrial freshwater fisheries Where do industrial freshwater fisheries exist? Caspian Sea … which is where?  Caspian Sea Mitrofanov & Mamilov (2015) Aquatic Ecosystem Health & Management 18(2): 160-170 Ruban & Khodorevskaya (2011) Journal of Applied Ichthyology 27(2): 199-208  Caspian Sea Bordered by Russia Azerbaijan Iran Turkmenistan Kazakhstan Endorheic water body No outflow All input from rivers Evaporative loss - Salinity of 1.2%, i.e., 1/3 of seawater Historically productive waters Sturgeon (caviar) Endemic anchovy/herring Why marine species, including Caspian seal? Mitrofanov & Mamilov (2015) Aquatic Ecosystem Health & Management 18(2): 160-170 Ruban & Khodorevskaya (2011) Journal of Applied Ichthyology 27(2): 199-208  Caspian Sea A remnant of the ancient Paratethys Sea (34–28 million years ago), i.e., part of the Tethys Ocean Eventually land-locked due to tectonic drift 10/28 Caspian Sea fisheries Small-scale Caspian Sea fisheries Industrial  Industrial freshwater fisheries Where do industrial freshwater fisheries exist? Caspian Sea Great lakes (USA/Canada)… mainly in the past (1850s – 1970s) Great lakes fisheries  Great lakes fisheries Only a few commercial (small- scale) fishers left Very large recreational sector 15/28  Industrial freshwater fisheries Where do industrial freshwater fisheries exist? Caspian Sea Great lakes (USA/Canada)… mainly in the past (1850s – 1960s) ????? Where else, historically ???? Aral Sea … which is where?  Aral Sea Ermakhanov et al. (2012) Lakes & Reservoirs: Science, Policy and Management for Sustainable Use 17(1): 3-9  Aral Sea Shared between Kazakhstan Uzbekistan Former USSR Formerly fourth largest lake in the world Endorheic water body No outflow Evaporative loss Began shrinking in the 1960s after the rivers that fed it were diverted by Soviet Union irrigation projects. Lake had largely dried up by the 2010s. Ermakhanov et al. (2012) Lakes & Reservoirs: Science, Policy and Management for Sustainable Use 17(1): 3-9  Aral Sea Ermakhanov et al. (2012) Lakes & Reservoirs: Science, Policy and Management for Sustainable Use 17(1): 3-9  Aral Sea fisheries 20/28 Ermakhanov et al. (2012) Lakes & Reservoirs: Science, Policy and Management for Sustainable Use 17(1): 3-9  Aral Sea fisheries Let’s return to the bigger picture and data situation… Ermakhanov et al. (2012) Lakes & Reservoirs: Science, Policy and Management for Sustainable Use 17(1): 3-9  Why would data quality be relatively worse in inland fisheries compared to marine? Two main reasons…. 1. Commercial fisheries all small-scale… no industrial fisheries (2-3 exceptions) … small-scale fisheries data deficient 2. Recreational fisheries increasingly dominate freshwater fisheries … largely unreported… even worse in data deficiency  Freshwater/inland fisheries Freshwater fisheries globally are dominated by small-scale sectors Artisanal & subsistence in developing countries Recreational in developed countries While reported catch volumes are low, underreporting likely higher than in marine systems Freshwater fisheries play a far more important food- and livelihood-security role in many countries, compared to marine fisheries Bartley et al. (2015) Fisheries Management and Ecology 22(1): 71-77 Funge‐Smith & Bennett (2019) Fish and Fisheries 20(6): 1176-119 Arlinghaus et al. (2015) Fisheries Management and Ecology 22(1): 45-55  Freshwater/inland fisheries Lake Volta (Ghana) 1996 reported = 75,000 t 1996 estimated = 150,00-200,000 t ~2-2.6 times higher Thai freshwater catches ~ 5 times higher than reported Mekong river countries Mainly China, Myanmar, Laos, Thailand, Cambodia and Vietnam Reported 1.6 MT Lower reaches alone actual catches estimated at 2.6 MT de Graaf & Ofori-Danson (1997) Catch and fish stock assessment in stratum VII of Lake Volta. Integrated Development of Artisanal Fisheries Project Technical Report No. 97/I. Rome, FAO. 96 pp. Lymer & Funge-Smith (2009) An analysis of historical national reports of inland capture fisheries statistics in the Asia- Pacific Region (1950-2007). Bangkok: FAO Regional Office for Asia and Pacific. RAP Publication, 18 pp. Hortle (2007) Consumption and the yield of fish and other aquatic animals from the Lower Mekong Basin. MRC Technical Paper No. 16. Vientiane, Lao PDR: Mekong River Commission, 87 pp.  Freshwater/inland fisheries What might be actual global catch… ~12 Mt reported? World Bank Big Number project: 13 MT… very limited estimate that excludes non-commercial subsistence 26 MT if consider a rough estimate of subsistence 50-60 MT based on assumption of 5x FAO reported 93 MT theoretical max production potential … but emphasis on tropical production rates and optimistic potential suggest overestimate Wide open research field for highly productive catch reconstructions…. exactly what my lab has begun to do Bartley et al. (2015) Fisheries Management and Ecology 22(1): 71-77 25/28 Sea Around Us – Indian Ocean Freshwater Hub Lead: Dr Wanja Nyingi Former Head of Ichthyology, National Museums of Kenya Focus on freshwater fisheries, ichthyology and aquatic ecology https://www.seaaroundus-io.org/freshwater Objectives: Address data shortfalls for freshwater fisheries – globally and regionally Develop novel projects on freshwater ichthyology & aquatic ecology Initial focal areas: Australia, Eastern Africa, South Asia Student interest in all things “non-salty” very welcome Wanja lecture: “Freshwater fisheries and ecology in Kenya”  Freshwater fisheries data CSIRO journal & reviewers: very supportive and keen to see this kind of research Wide open research field Pioneering stage for freshwater catch data work Less controversial due to lower industry capture of science Sea Around Us – Indian Ocean