Spatio-temporal Analyses of Marine Predator Diets from Data-rich and Data-limited Systems

Authors

Arnaud Grüss, University of Washington
James T. Thorson, Habitat and Ecological Processes Research Program, Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle
Gemma Carroll, Institute of Marine Science
Elizabeth L. Ng, University of Washington
Kirstin K. Holsman, Resource Ecology and Fisheries Management Division, Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle
Kerim Aydin, Resource Ecology and Fisheries Management Division, Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle
Stan Kotwicki, Resource Assessment and Conservation Engineering Division, Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle
Hem N. Morzaria-Luna, Intercultural Center for the Study of Deserts and Oceans, Inc. (CEDO), Tucson
Cameron H. Ainsworth, University of South FloridaFollow
Kevin A. Thompson, Fish and Wildlife Research Institute

Document Type

Article

Publication Date

2020

Keywords

diet proportions, Poisson-link delta model, predation pressure, predator-expanded-stomach-contents, spatio-temporal model, stomach content data

Digital Object Identifier (DOI)

https://doi.org/10.1111/faf.12457

Abstract

Accounting for variation in prey mortality and predator metabolic potential arising from spatial variation in consumption is an important task in ecology and resource management. However, there is no statistical method for processing stomach content data that accounts for fine-scale spatio-temporal structure while expanding individual stomach samples to population-level estimates of predation. Therefore, we developed an approach that fits a spatio-temporal model to both prey-biomass-per-predator-biomass data (i.e. the ratio of prey biomass in stomachs to predator weight) and predator biomass survey data, to predict “predator-expanded-stomach-contents” (PESCs). PESC estimates can be used to visualize either the annual landscape of PESCs (spatio-temporal variation), or can be aggregated across space to calculate annual variation in diet proportions (variation among prey items and among years). We demonstrated our approach in two contrasting scenarios: a data-rich situation involving eastern Bering Sea (EBS) large-size walleye pollock (Gadus chalcogrammus, Gadidae) for 1992–2015; and a data-limited situation involving West Florida Shelf red grouper (Epinephelus morio, Epinephelidae) for 2011–2015. Large walleye pollock PESC was predicted to be higher in very warm years on the Middle Shelf of the EBS, where food is abundant. Red grouper PESC was variable in north-western Florida waters, presumably due to spatio-temporal variation in harmful algal bloom severity. Our approach can be employed to parameterize or validate diverse ecosystem models, and can serve to address many fundamental ecological questions, such as providing an improved understanding of how climate-driven changes in spatial overlap between predator and prey distributions might influence predation pressure.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

Fish and Fisheries, v. 21, issue 4, p. 718-739

Scholar Commons Citation

Grüss, Arnaud; Thorson, James T.; Carroll, Gemma; Ng, Elizabeth L.; Holsman, Kirstin K.; Aydin, Kerim; Kotwicki, Stan; Morzaria-Luna, Hem N.; Ainsworth, Cameron H.; and Thompson, Kevin A., "Spatio-temporal Analyses of Marine Predator Diets from Data-rich and Data-limited Systems" (2020). Marine Science Faculty Publications. 1857.
https://digitalcommons.usf.edu/msc_facpub/1857