Speaker: Will White, Associate Professor, Oregon State University

Topic: When and how local management actions can improve resilience to climate-change-driven tipping points: examples from kelp forest ecosystems

Marine heatwaves have become widespread stressors affecting coastal ecosystems worldwide, pushing them across tipping points into degraded states. Though the ultimate problem is global, there is a short-term need to find conservation tools that can enhance ecosystem resilience of ecosystems at a local scales. In the case of kelp forest ecosystems, heatwaves both reduce kelp growth and increase kelp herbivory by sea urchins, tipping systems into a persistent, degraded 'urchin barren' state. There are a variety of management actions that could improve resistence and resilience, from physically removing sea urchins, to re-seeding kelp, to employing marine protected areas (MPAs) to protect predatory fish that eat urchins. However, it is challenging to know how much of any one of those activities, or in what combination, would be the best use of limited resources. Additionally, we can forecast that some coastal areas will become more vulnerable to heatwaves in the future, while others may remain climate refugia, but it's not clear which of those areas should be targeted for protection and restoration. In this talk I will show how using mathematical models of kelp forest communities can guide those management decisions, and lead to different recommendations in different ecological contexts.