Shifting Forests: Examining Community Responses to Kelp Decline PDF

Shifting Forests: ExaminingCommunity Responses to aCatastrophic Decline of Kelp Along the NorthernCaliforniaCoast * Cue SCUBA bubble sounds *  Dynamic Ecosystems constant change and adaptation consistent community configurations Regime Shifts Regime Shifts Regime Shifts Remnant fragme...

Shifting Forests: ExaminingCommunity Responses to aCatastrophic Decline of Kelp Along the NorthernCaliforniaCoast * Cue SCUBA bubble sounds *  Dynamic Ecosystems constant change and adaptation consistent community configurations Regime Shifts Regime Shifts Regime Shifts Remnant fragmented habitat patches = Focal study patches Disturbance-Diversity Relationship Are diverse ecosystems inherently more stable and resilient to disturbances? Intermediate Disturbance Hypothesis Diversity I D H Disturbance Kelp Forest Urchin Barren Tavish Campbell Steve Lonhart Kelp Forests and Disturbance Kelp Forests Global Decline  Multiple Disturbance Events The Sea Otter Enhydra lutris The Ochre Star Pisaster ochraceus The Sunflower Star Pycnopodia helianthoides  Multiple Disturbance Events The Ochre Star Pisaster ochraceus Intermediate Disturbance Hypothesis (IDH) Diversity I D H Disturbance Northern California Kelp Forests Collapse Rogers-Bennett, L., Catton, C.A. 2019 Beyond the Paradigm  Nereocystis Pterygophora annual create 3D structure perennial surface canopyfood source understory grows up to habitat ~100-120 ft grows up to ~7.5ft Study Site: Big River, Mendocino Headlands  Study Objective Understand the community structure of invertebrates and fish during two life stages (adult and recruited early post-settlement) across three functionally different habitat regimes: canopy algae crust forming kelp understory kelp  Study Questions & Hypothesis Are there differences across habitat regimes in: 1.density of key adult invertebrates and fish 2.recruitment densities of invertebrate and fish 3.community structure (for both recruitment and adult life stages) 4.functional groups  Hypothesis I hypothesize that differences across regimes will be most notable between Nereocystis-Reef & Pterygophora-Reef regimes, while Nereocystis-Pterygophora will have the least differences  Q1 semi transparent font to remind the audience what ? I’m talking The ANOVA did not Apriori Habitat Designation Kruskal-Wallis: χ2 = 24.17 df = 2 p < 0.00001 Apriori Habitat Designation Kruskal-Wallis: χ2 = 36.18 df = 2 p < 0.00001  A priori habitats The ANOVA did not fully support my a priori habitat differentiation at Big River. Nereocystis & Reef regimes were significantly different, but Pterygophora density was not distinctly different between Nereocystis-Pterygophora regimes  Study Objective Understand the community structure of invertebrates and fish during two life stages (adult and recruited early post-settlement) across three functionally different habitat regimes: canopy algae crust forming kelp understory kelp Q2: and Methods Adult Invertebrates Kruskal-Wallis: χ2 = 15.11 df = 2 p = 0.0005 Area: per 1m diameter get rid of squared and put plot VERY IMP!! Adult Invertebrates Kruskal-Wallis: χ2 = 25.54 df = 2 p < 0.000001 Adult Invertebrates Kruskal-Wallis: χ2 = 2.29 df = 2 p = 0.32 Discussion: Adult Inverts & Fish Densities sig diff in adult urchins and tegula snails are only between forested-non-forested habitat regimes legacy impacts of SSW nearly a decade after Q ACM & Methods  Invertebrate & Fish Recruitment Does invertebrate and fish recruitment vary across habitats? Urchin Recruitment Kruskal-Wallis: χ2 = df = p= Cancer Crab Recruitment Kruskal- Wallis: χ2 = df = p= Q: Kelp Crab Recruitment Kruskal-Wallis: χ2 = df = p=  Tegula snails Recruitment Kruskal- Wallis: χ2 = df = p= Low Sea Star Recruitment  Q: Fish Recruitment Kruskal- Wallis: χ2 = df = p= Low Cancer Crab Recruitment Cancer antennarius Pictures coming soon Cancer jordani Cancer anthonyi Discussion: Recruitment of Inverts and Fish Understanding Urchin Recruitment is important for grazer removal efforts Sea stars overwhelmingly recruiting to Nereocystis Adult Community Structure Adult Species Composition Across Habitat PERMANOVA: df = 2 SumOfSqs=2.83 𝑅 2 = 13.63 F = 10.41 p < 0.001 Recruitment Community Structure PERMANOVA Recruitment Composition Across Habitat df = 2 SumOfSqs = 1.14 𝑅 2 = 0.08 F=0 p = 0.044 PAIRWISE ptery-Nereo p = 0.75  Results Summary : Community Structure Lack of kelp persistence is detrimental to adult invertebrate success Bottleneck effect or Behavioral Changes? 3-d habitats, ontogenetic shifts : diff dietery needs across diff life stages talk about all the other effects (habitat refugia) Recruitment: Functional Groups Functional Group Organisms Generalists Crepidula snails, hermit crabs, chitons, crabs, fish, flatworms and nematodes Herbivores Snails, limpets, and urchins Predators Sea stars, sculpin fish Filter feeders Mussels, clams, and scallops Generalized Linear Mixed Models (GLMMs): Functional Group ~ Habitat Used Akaike Information Criterion (AIC) values for model selection Random Factors: Plot ID & Month Predators GLMM: gaussian distribution Plot ID: variance = 0.07, plot id SD = 0.27 Nereo-Ptery (**) : Nereo-Reef(***) : Estimate = 0.699, SE = 0.21, p = 0.003 Estimate = 0.921, SE = 0.22, p = 0.0003 Q: Filter Feeders GLMM: negative binomial distribution Month: variance = 0.28, plot id SD = 0.53 Nereo-Reef(*) : Ptery-Reef (*) : Estimate = 0.921, SE = 0.22, p = 0.0003 Estimate = 0.85 , SE = 0.34, p = 0.035 Q: Herbivore and Generalists  Discussion: Functional Groups Functional Redundancy across the forested regimes is important and should be explored further more species= better buffering capacity functional redundancy prevents ecosystem collapse when certain species are lost Overall Discussion / Greater Significance The role of Pterygophora and other understory Kelp as a habitat for fish should be explored further Data-driven management for reopening fisheries feasibility Expand our restoration goals to understory kelps References Ecosystems - Coastal, Marine (vecta.io) Shale Clipart PNG, Vector, PSD, and Clipart With Transparent Background for Free Download | Pngtree Free Underwater Bubbles Sound Effects Download – Pixabay Page 3 | Subtidal Vectors & Illustrations for Free Download | Freepik 41,494,344 Boulder Vector Images | Depositphotos Underwater Vectors & Illustrations for Free Download | Freepik IDH Insurance Hypothesis Watson et al., 2018 Sea Star Wasting Syndrome | MARINe (ucsc.edu) ¿El Niño Godzilla? Canal Clima  Acknowledgments Thesis committee Drs: Brent B. Hughes, Marisol García-Reyes, Lisa Patrick Bentley Lab mates Alyssa Cooper, Abbey Dias, Julieta Gomez, Emily Hascall, Rachael Karm, Vini Souza, and Shirah Strock SSU Administrative staff Rosemary Galten, Kandis Gilmore, Liz Kettmann, and Stephanie Thibault Undergraduate assistants Fern Adams, Abigail Culpepper, Taylor Nelson, Tiffany Ko Mendocino community Dr. Ann Russell? Fire Chief John Psias Friends, Blechel Family, Jacob, y Mi Familia To all the funders & institutions that made this possible ☺ Questions?