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Evaluating dynamics of the Puget Sound groundfish community: Laying the foundation for climate impacts studies. Tim Essington School of Aquatic and Fishery Sciences UW Climate Impacts Group. Need for Climate Impacts and Forecasts.
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Evaluating dynamics of the Puget Sound groundfish community: Laying the foundation for climate impacts studies Tim Essington School of Aquatic and Fishery Sciences UW Climate Impacts Group
Need for Climate Impacts and Forecasts • Account for anticipated growth and climate change. Our region is growing fast and changing. We can help accommodate this growth through: projects, regulations, and incentives to better protect intact areas; focusing growth in urban areas; conserving freshwater resources; and protecting working farms and forests. Actions to adapt to and mitigate for climate change are included.
Methods for Climate Impacts and Forecasts: Marine fish and fisheries • Statistical • Integrated bio-physical models • Integrated bio-physical-social models
Methods for Climate Impacts and Forecasts: Marine fish and fisheries • Statistical • Patterns of variance • Relate that variance to bio-physical drivers • Integrated bio-physical models • Integrated bio-physical-social models
Outline • Data synthesis • Historical data • Contemporary time series data • Hypoxia Impacts • Climate link? • Nature and magnitude of biological responses
Historical Baseline Project • What was “normal” in the mid 20th century • Was the Puget Sound food web fundamentally different then versus now? • Which changes are likely attributable to climate?
School of Fisheries Logbook Data • Longest, most consistent historical data records • Mostly bottom trawls (targeting benthic and demersal communities) • Most data from central Puget Sound, some from Whidbey basin
SOF Logbook Data 1661 Trawls in Puget Sound, 1948-1977
Surprise! English Sole Catch Rate, 1947-1975
Reality • Time and location of samples • Little support for “time” effect • Challenges in using these data (standardization needed)
School of Fisheries Logbook: Ratfish ~ 44% (by number) of catch in deep tows Slightly less then contemporary data Difference comes from absence of rockfish
Gadids: then and now • In School of Fisheries data, pacific cod present in one-third of tows (deeper than 30 meters) • 220 out of 671 (33%) • Presently, Pacific Cod is essentially absent from Puget Sound • My research, 1 out of ca. 150 tows “the” cod
Gadids then and now: where do all the pollock go? • School of Fisheries data • “Large” pollock in 22 of 34 tows that gave size information • If pollock were caught, 2/3 chance that at least one adult pollock was captured • Contemporary • Small pollock are common (age 0 to age 1) and episodic • Adult pollock are extremely rare Photo by Johanna J. Vollenweider
Next Steps • Compare compositional data to contemporary data (with WDFW) • Identify guilds that have undergone profound shifts • Support Integrated Ecosystem Assessment modeling
Tom Quinn’s Fish Ecology Trawl Survey Same boat Same net Same captain Same sites Same times Same dates 1991-2008 Contemporary Time Series
Time series followed bottomfish fishery closure (1989) Expectation
Unexpected Patterns English Sole
Flatfish Dynamics English Sole Rock Sole Catch Anomaly Slender Sole Flathead Sole
Episodic Species Shifted Too Pac. Tomcod Shiner Perch Walleye Pollock Pac Hake
Alternative Hypotheses • Population Response • Expect evidence of strong and weak cohorts • Cohort strength should be maintained across years • Local dynamics reflected in larger Puget Sound • Phenology Response • Unknown phenology of movement among habitats, but perhaps have shifted?
Significant shifts in length frequency 1991, 1993 and 1995 are putative good year classes Few strong cohorts since 3 1 2 English Sole Cohort Analysis
Unexpected Patterns English Sole
Putative Environmental Correlates • Temperature (esp. for phenology) • Salinity • Data from King County and DOE, 1991-2008 • CTD casts from Jefferson Point and West Point
Was there a significant shift in water temperature? Mean Temp Anomaly Feb – May, 30-35 m Temperature Anomaly Putative English Sole strong year class
What about salinity? Mean Feb – May salinity, 30 – 35 m depth
Bottom Line • Good News: there’s variance to analyze ! • Bad News: nothing seems to explain it ! • Other “drivers” not considered • Advection fields • Primary production • Zooplankton composition, abundance and phenology • Need to look Puget Sound wide (WDFW collaboration) • Indirect effects may be important • Modeling needed to identify indirect effects (C. Harvey, NOAA fisheries)
Evaluating Impacts of Hypoxic Events on Demersal Fish and Invertebrates
Intensity of Seasonal Hypoxia and Springtime Conditions Data from HCDOP Citizens Monitoring Program
Hypoxia Impacts in Hood Canal unimpacted Seasonal hypoxia
Hypothesized Effects • Persistent effects: those present in Hoodsport even when DO is high • Demographic • Immediate effects: those present in Hoodsport that are only manifest during hypoxia • Behavioral
General Results June September
Estimating Effect Sizes • Generalized Linear Model • Negative Binomial error function • Effect sizes through maximum likelihood and likelihood profiles • Incorporate uncertainty due to alternative hypotheses • Account for confounding effects of depth, time period • Hierarchical Bayesian Analysis: integrate effect sizes over all species within a group
Groups • Sessile Invertebrates • expected persistent effects to dominate • Mobile Invertebrates • expected mixed results • Benthic Fishes • expected immediate effects to dominate • Demersal Fishes • expected immediate effects to dominate
Less Abundant More Abundant Less Abundant More Abundant Spiny Red Star Vermillion Sea Star Metridium Sea Anenome Rose Star Stomphia Sea Anenome Group Average Persistent Impact Immediate Impact
Sessile Invertebrates Spiny Red Star Vermillion Sea Star Metridium Sea Anenome Rose Star Stomphia Sea Anenome Group Average Mobile Invertebrates Alaska Pink Shrimp Decorator Crab Dungeness Crab Graceful Crab Sunflower Star Red Rock Crab Sidestripe Shrimp Spot Prawn Squat Lobster Sand Star Coonstripe Shrimp Group Average Persistent Impact Immediate Impact
Benthic Fishes Blackbelly Eelpout Blackfin Sculpin Blacktip Poacher Dover Sole English Sole Pacific Sanddab Rex Sole Rock Sole Roughback Sculpin Slender Sole Group Average Demersal Fishes Longnose Skate Pacific Hake Pacific Tomcod Plainfin Midshipman Quillback Rockfish Ratfish Shiner Perch Spiny Dogfish Walleye Pollock Group Average Persistent Impact Immediate Impact
Main Conclusions • Profound impacts on sessile invertebrates • “Scavenger” feeding guild severely depressed • Mobile species tended to show immediate response
Does hypoxia create a “hake factory” What is the impact of hake predation on salmon?
Implications • Hake, hake, and more hake • Jellyfish and hypoxia • Indirect effects from behavioral response • Feeding • Vulerability to predators • Growth • Population linkages • Modeling (Ecopath) ongoing
Future for Climate Impacts in Puget Sound • Hood Canal, hypoxia and climate • Significant baseline variation in demersal food web • Ongoing modeling, statistical analysis needed • Pelagic food webs: Herring, jellyfish and climate (Jon Reum Ph.D. dissertation)