Larval dispersal in a changing ocean: patterns, causes, and consequences

点击翻译按钮获取中文摘要

Throughout the world's oceans, climate change and a suite of other anthropogenic stressors are degrading marine habitats. Nowhere are these changes more acute than on coral reefs, which are experiencing devastating thermal stress events at increasing frequencies and intensities. In the face of such dire threats, there is an urgent need to understand the ecological processes that underpin biodiversity persistence in rapidly changing seascapes. One essential process is dispersal, which the majority of marine species undertake during a larval phase. Despite decades of progress towards describing dispersal patterns, we still lack fundamental knowledge about the scale of dispersal for most species. Moreover, we have a poor understanding of the mechanisms driving dispersal variability under present oceanic conditions, as well as how climate-induced changes to individual phenotypes and seascape quality will affect dispersal in the future.      Over the next five years, my lab will investigate how seascape heterogeneity (i.e. habitat quality, loss, and fragmentation) influences larval dispersal. We will focus on microhabitat specialist fishes on reefs surrounding the Caribbean island of Curaçao. These are ideal study species because they occupy invertebrate hosts (e.g. corals, sponges); thus, their persistence is tightly linked to the health of the reef-building invertebrates they live on. Drawing on techniques from field biology, molecular ecology, conservation biology, and seascape ecology, we will address three major objectives. First, we will quantify regional patterns of dispersal across a strong environmental gradient using innovative techniques in genetic parentage analysis. Second, we will begin to unravel the biological mechanisms driving the observed dispersal patterns by exploring how habitat quality affects larval dispersal phenotypes and adult reproductive tactics. Third, we will integrate these unique empirical data into models that predict how fish populations will respond to alternative conservation strategies aimed at mitigating ongoing seascape degradation.      Collectively, this research program will provide much-needed empirical data on ecological processes that underlie marine biodiversity persistence in the face of continued exploitation and habitat degradation. It will make important contributions to our understanding of larval dispersal in the Anthropocene and will have direct implications for climate-smart conservation planning on coral reefs-the world's most imperiled marine ecosystem. More generally, the framework we establish for studying larval dispersal on dynamic reef seascapes can inform work in other regions, including Canada-a country surrounded by three oceans that are all experiencing the effects of climate change. This grant will also provide training to five graduate and 10 undergraduate students, who will simultaneously address consequential questions in marine ecology and applied issues in conservation biology.