Research

We study population and community dynamics in primarily coastal marine ecosystems with the goal of integrating the many influences on marine species. We use population genetics, and increasingly genomics, along with meta-analyses to expand our vision deeper in time, farther across the seascape, and across a wider range of species than would be possible with more traditional techniques. A sampling of our projects is below.

How do marine communities respond to climate change?

Climate change is not just an increase in temperature or change in environmental conditions; it’s also a velocity across the seascape as species’ preferred conditions move to new locations. While it’s clear that species distributions shift as climates change, our understanding of the mechanisms, causes, and consequences remain limited. Can all species keep up with rapid climate velocities? How does climate interact with other factors, like habitat, currents, fishing, food web dynamics, and evolution? The consequences for fisheries and the coastal towns that rely upon them are also substantial, and yet fisheries management is only just beginning to consider climate change. How do fishermen adapt to the changes, and what are the feedbacks of these coping mechanisms to the natural world? Understanding the dynamics of this coupled natural-human system will require new theory that scales from the local processes of population dynamics and species interactions to the large-scale sustainability of the system. To date, we’ve focused on North American coastal species and fisheries, building large databases of observations against which we can test broad hypotheses, as well as developing case studies, mathematical models, and field systems to explore  dynamics in more detail.

Where do baby fish go, and what are the consequences?

IMG_3255_mod_cropDispersal can drive population dynamics, range limits, and local adaptation, but a first step in understanding these processes is to understand how far organisms disperse. Using coral reef fishes (Amphiprion and Premnas spp.) as a model system, we apply population genetic and modeling tools to understand how far larvae move in a single generation, how this dispersal affects population dynamics, and how to design more effective conservation strategies given this knowledge (particularly marine protected areas and other spatial management approaches). Our field work is primarily in the central Philippines, but additional collaborations have focused in Kimbe Bay, Papua New Guinea. Recent work has allowed us to begin integrating oceanographic models into our work, and to exploring the tensions between dispersal and local adaptation across the genome of coral reef fishes.

How have species coped with catastrophic events in the past?

Looking back in time, we see that some species have been amazingly resilient in the face of large-scale disturbance from climate, exploitation, or other factors, while other species have not. What allows these species to survive, and what does that tell us about species recovery? One way to answer these question is to look back in time and reconstruct what happened. Our projects to date have reconstructed dispersal patterns and colonization/extinction dynamics in pinnipeds over the last few thousand years. This research primarily uses ancient DNA and Approximate Bayesian Computation techniques to draw ecological inferences from genetic data.

How do we measure the value of clean water, abundant wildlife, and protection from storms?

Guerryetal2012Fig4iFor centuries, our societies have been better off thanks to a wide range of benefits provided by coastal ecosystems. These include obvious goods like food from fishing and aquaculture, but also more subtle services like coastal protection from mangroves, or newly emerging services like wave energy. While we can list these benefits qualitatively, understanding their magnitude has been much more elusive. How do human activities alter these benefits? Can we manage coastal ecosystems for a wide range of benefits, or are there important tradeoffs? How do we predict the goods and services we’ll get from a natural or a disturbed seascape? We are working to to answer these questions, in part through collaborations with the Natural Capital Project.