Dive into a coral reef almost anywhere in the world and you are overcome with the tranquil beauty of living color undulating, swimming, and swaying beneath you.
Dive into the waters of Palmyra Atoll and – if you are like me – your first thoughts are: “Holy Hell, does that large animal swimming my way intend to eat me??”
All of the same colorful reef life exists at Palmyra, but it undulates, swims, and sways around one of the densest concentrations of large fish in the world. It is the extreme remoteness of Palmyra that protects these animals – like sharks, manta rays, and parrotfish – from overexploitation and allows them to persist at high densities. These special conditions provide a valuable opportunity to examine the ecological importance of large fish.
My research uses the uniqueness of Palmyra to isolate the role that large reef consumers play in their ecosystems and to assess how their loss affects those ecosystems. I focus specifically on describing the direct and indirect effects of large fish on coral reef communities, the mechanisms by which large fish connect different reef habitats, and facets of the ecology of vulnerable large fish species that are directly relevant to their management. I use a variety of research tools to meet these aims: experiments that exclude large fish from sections of reef in 
order to mimic the effects of overfishing; chemical tracers that show how large consumers link distant or distinct habitats; animal tracking, which reveals how large animals traverse ecosystems and use resources distributed across those ecosystems; computer simulations populated with information collected at Palmyra to make predictions about change in reefs; and observational comparisons between Palmyra and nearby, fished reefs.
My work has been greatly improved by collaborations with colleagues at Stanford and other PARC institutions. These joint efforts have contributed to our understanding of the ecological consequences of the loss of large fish from reefs, have helped us to better understand why and how large fish declines occur in coral reef settings, and have provided resources that will help coral reef managers.
Our ultimate goal? To glean from Palmyra’s reefs lessons that will help us protect large fish populations and whole coral reef ecosystems across the globe.
