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Despite the apparent variety of the ongoing research projects in my lab, all of our research aims to understand the role of spatial and temporal patterns in ecological processes at spatial scales ranging from sub-meter to hundreds of kilometers, at temporal scales of minutes to years, and over a range of animal size from zooplankton to great whales.

  Diving murres    
  Active research projects in the lab all focus on the role of spatial and temporal patterns in ecological processes. For example, working with a large team of collaborators, we have been quantifying the role of prey distribution in determining the behavior and population dynamics of fur seals and marine birds in the Bering Sea. At the same time, we've been examining how the physical and biological habitat influence the abundance and behavior of pollock and krill, key prey within this ecosystem. We found that patches of pollock and krill are driven by behavioral interactions with the habitat, not the numbers of individuals. The predators cue in on these patches rather than prey numbers, a surprising result and one that makes it challenging to predict the behavior of these protected predator species given current prey survey protocols.      
  Off Hawaii, we used a combination of continuously sampling moored sensors, complemented by shipboard sampling, to measure the temporal variation, abundance, and vertical distribution of four trophic levels in Hawaii's nearshore pelagic ecosystem. We found that patches of organisms are what structure this ecosystem as well as driving the behavior of the top predator, the spinner dolphin. The importance of spatial pattern in ecosystems has long been recognized. However, this work helps incorporate patchiness into our understanding of forces regulating ecosystems, a problem that has proven challenging.   Dolphins    
  Often, the questions I am interested in cannot be addressed with existing approaches or technologies which means making new fundamental measurements or engineering new tools. A few years ago, we worked with colleagues to develop an acoustic method for detecting free-swimming squid. Despite a long-held idea that it would be impossible to use sonar on squid because of their lack of a swimbladder, we have been able to successfully detect, size, and track squid using acoustic tools. That has led to a number of new projects. Studies of jumbo squid in the Gulf of California have revealed how they change their behavior to be able to use different prey over the course of the day and night. We have also observed how groups of squid swim carefully together while hunting, a behavior that looks a bit like a ballet, to gain access to food while avoiding each other. These squid have recently invaded the west coast of the United States. We are observing how squid behavior here compares to that we've observed in their natural habitat in the Gulf of California. We're also trying to learn what the effects of squid are on a Pacific hake, the target of the largest fishery on the west coast.   Squid    
  In addition to being important and understudied predators, squid are important prey for many species. Unfortunately, our acoustic methods are limited to the upper water column and squid predators like sperm whales and beaked whales feed at depths of 1000 m (3000 ft) or more. Along with partners at other institutions, we've developed a new tool – an underwater robot that carries our instruments deep into the ocean. This is allowing us to look at squid at the depths important to predators while simultaneously looking at the behavior of the predators. Our results are beginning to be able to provide insights into the ecology of both the predator and the prey, information necessary for conservation and management.   Fish    
  Autonomous platforms provide other opportunities as well, allowing us to have a persistent presence in challenging habitats. We're exploiting these advantages by developing a low power autonomous echosounder glider. More than just a new platform, in collaboration with robotic control engineers, we will use what we know about how predators hunt in the sea to make the glider sample intelligentily, seeking out biological hotspots using a suite of physical and biological cues. The glider will "think like a fish" in order to examine the responses of plankton, fish, and seabirds to the intra-seasonal dynamics of coastal upwelling.   Glider    
  Funding for our research comes from a variety of sources including the National Science Foundation, the Office of Naval Research, the Army Corps of Engineers, the North Pacific Research Board, the Strategic Environmental Research and Development Program, and the Keck Foundation.