UW Aquatic & Fishery Sciences Quantitative Seminar

Austin Phillips

Quantitative Ecology & Resource Management, University of Washington

Will spatial transients help or hinder species responding to climate change?

Abstract

Climate change is moving many species' suitable habitats, forcing populations to either track their habitats using dispersal, adapt in situ, or face extinction. While a number of mathematical frameworks exist to model species' response to climate change, most models focus on long-term (asymptotic) population dynamics. In contrast, most management decisions occur on the time scale of short-term (transient) dynamics. Transient behavior can often differ greatly from asymptotic dynamics, leading to poor management decisions (e.g., conserving species that would do fine on their own, or failing to conserve species that are at risk). In this talk, I will use an integrodifference model to explore the transient dynamics of a population tracking its moving habitat. Although transient dynamics are usually studied in the context of non-spatial stage-structured or multi-species models, we will see that strong transients can occur in single-species spatial models. Using a variety of analytical and numerical techniques, I will highlight three model results with management implications. First, transient dynamics can only occur under a certain set of biological and environmental conditions. Second, the model pinpoints the optimal location to augment population levels for persistence. Third, the model offers an explanation for critical slowing-down-the observation that systems near a tipping point often exhibit long transient dynamics.