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Integrating habitat, prey and predators over space and time to assess distributional responses to environmental variability and climate change

Released: 2015
Barceló, C, C Coleman, B Wright, R Brown, J Adams, LT Balance, R Brodeur, LG Torres. 2015. Integrating habitat, prey and predators over space and time to assess distributional responses to environmental variability and climate change. 21st Biennial Conference on the Biology of Marine Mammals: Bridging the Past Toward the Future, San Francisco, CA. 13-18 December 2015.

Impacts of climate change on the distribution of marine predators have typically been assessed in isolation from aspects of community ecology, such as predator and prey relationships. This omission can limit our potential to understand, anticipate and respond to changes in ocean ecosystems. Our research uses species distribution models (SDMs) to integrate habitat, prey and predators to achieve more realistic spatial predictions. We generated SDMs of California sea lions and their prey items off the Oregon and Washington coasts to (1) describe and compare habitat use patterns, (2) predict distribution patterns under various temporal and climate change scenarios, and (3) evaluate the ecological and management implications of overlap or mismatch between predator and prey. Prey SDMs are based on pelagic fish surveys conducted 2-3 times annually since 1998 that frequently catch sea lion prey (mackerel, sardine, hake, herring). Predator SDMs of California sea lions are based on previously collected distribution data, across the same spatial and temporal, from satellite telemetry, and boat-based and aerial surveys extents. Seasonal models of predator and prey are generated using the same suite of environmental variables including static features, remotely sensed oceanographic data, and ecosystem regime status (e.g., ENSO index). Prey models demonstrate distinct habitat and distributional patterns between fish species, including increased herring abundance along the inner shelf, while mackerel abundance increases offshore. We couple and compare these prey SDMs with predator models in the same region to describe spatial overlap and spatial shifts of predator and prey model predictions under various environmental scenarios (average conditions, ENSO cycles, and forecasted climate change). These methods synoptically compare habitat preferences and distributional responses of California sea lions and their prey to environmental variability. Our results describe how the permeating effects of climate change and cyclical environmental conditions will impact the redistribution marine predators and their prey.








This product is associated with the following project:
Pacific Continental Shelf Environmental Assessment (PaCSEA)

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