Seabird Ecology in the Bering Sea

What Are They Doing?

The research team studied the foraging behavior of seabirds nesting in the Pribilof Islands. Specifically, they were interested in two piscivorous seabirds – the Thick-billed Murres and Black-legged Kittiwakes – on St. George and St. Paul Islands.

The team conducted this research to determine how climate warming and sea ice retreat from the southern portions of the Bering Sea will impact seabird nesting success and population growth rates on these islands.

To help gather data, team researchers used Global Positioning System (GPS) technology to track breeding seabirds when they foraged at sea. They also employed time-depth recorders (TDRs) to determine the amount of time the birds spent on the water surface, as well as how deep and often they dived.

The information they gathered using this equipment and their direct observation helped to confirm where birds from each island find food and how sea ice extent affects the feeding locations and trip length. They also got a better understanding of the effects of foraging behavior on colony diet, reproductive success, and adult survival.

This project contributed to a larger collaborative effort between the National Science Foundation and the North Pacific Research Board called the Bering Sea Integrated Ecosystem Research Program.

Where Are They?

The team conducted research on St. George and St. Paul Islands, which are located in the southwestern Bering Sea and are part of the state of Alaska. These islands, and two other much smaller ones, form a group of islands known as the Pribilof’s. There is a small town of approximately 150 people on St. George and one of approximately 500 on St. Paul. To reach the islands, the research team flew on a commercial airline.

Expedition Map


Tomorrow is the first day of school. My summer whirlwind of juggling work and home responsibilities, packing and traveling and participating in an amazing research project are coming to an end and a new year is beginning. It is a strange transition in many ways. I've traded in my bulky cold weather gear for shorts and a t-shirt. My shifts on the cliff watches have given way to hours of work in the yard. It's been an incredible journey that really began well before I first stepped off of the plane onto St. Paul Island. ATVs were the way we got around on the island, they were lots of fun...
As I had mentioned in one of my earlier journal entries, I had to miss one of the summer center programs that I normally teach since the session got underway right around the time that I needed to leave for the Pribilofs. The participants in the Maryland Summer Center for Aquatic Research demonstrate a strong interest in environmental science and go on to develop final projects about their summer research that are top-notch. On St. Paul Island I had a chance to meet up with students participating in a similar program with a focus on the marine science of the Pribilofs. The students ranged in...
My father kindled my interest in birds when I was a boy. He would take my brothers and me up to the local hawk watch site on Hook Mountain in the lower Hudson Valley of New York State. We'd see red-tailed hawks, kestrels and lots of turkey vultures passing overhead on their southward migration. As I got a bit older, I would join him on Christmas Bird Counts, hiking up a mountain path in the pre-dawn darkness, hooting up great horned owls in the pine grove near the top of the hill. My Dad is gone now, but I know that he'd be tickled at the experience that I've had here on St. Paul Island...
 High above the sea on the cliffs at Zapadni Dip or as we call it "Zap Dip", we get to observe the ebb and flow of life around the edge of the southern Bering Sea. Each day that we come out on our watches at the murre colony our job is to record data about the feeding by the parent birds to their hungry offspring.As the days have turned into weeks, we have seen some of these chicks grow and develop and leave the nest. Others are not so fortunate. A turn of events that to our eyes, seems so random as a squabble by two neighboring birds that results in a chick or an egg getting...
Sitting, just sitting still in a natural area for an extended period of time offers one a glimpse into the natural world that goes completely unobserved when a person is in motion, no matter how fast or how slow you are walking. Hunters know this. My brother is a hunter and has told me stories of birds, even birds of prey, landing a short distance from his tree stand in the forest, not because he is camouflaged or otherwise hidden, but because he is quiet, because he remains still.I believe that two factors are at work during this type of watching of the natural world. I think that when...

Expedition Resources

Project Information

15 July 2009 to 15 August 2009
Location: Pribilof Islands, Alaska
Project Funded Title: Seabird Telemetry - Bering Sea Integrated Ecosystem Research Program

Meet the Team

Thomas Harten's picture
CHESPAX, Calvert County Public Schools
Prince Frederick, MD
United States

For 17 years, Tom Harten has been a teacher with the CHESPAX environmental education program in southern Maryland. Authentic research projects and environmental action have been central to the success of this program where K-12 students use the Chesapeake Bay and surrounding watershed as an outdoor learning laboratory. Mr. Harten has a degree in outdoor education and a master’s degree in science education from the University of Memphis, with certifications in Earth and space science and outdoor education. As lifelong birder and naturalist, Mr. Harten has traveled extensively in the U.S. and in the tropics in pursuit of these interests. He also enjoys canoeing, camping, running, and, most of all, spending time with his wife Tracy and son Jake. He is looking forward to the PolarTREC experience in the Pribilof’s because it will be a fantastic opportunity to study seabirds at close range and to add to our knowledge of these fascinating creatures.

Rosana Paredes's picture
Oregon State University
Corvallis, OR
United States

Rosana Paredes is a Post-doctoral Research Associate with Oregon State University and Project Leader of the Seabird Telemetry Component of the Bering Sea Integrated Ecosystem Research Program (BSIERP). She will be working on St. George Island this summer. Dr. Paredes has conducted biological research in Peru, Canada, and Alaska and her main areas of scientific interest include animal behavior, ecology, and the conservation of marine ecosystems.

Dan Roby's picture
Oregon State University
Corvallis, OR
United States

Daniel Roby is currently the Assistant Unit Leader at the U.S. Geological Survey Oregon Cooperative Fish and Wildlife Research Unit and Professor of Wildlife Ecology in the Department of Fisheries and Wildlife at Oregon State University. He received a B.A. in biology from Antioch College, a M.S. in wildlife management from the University of Alaska in 1978, and a Ph.D. in biology from the University of Pennsylvania in 1986. Dr. Roby has conducted research on the ecology of seabirds in Alaska, Hawaii, Greenland, Newfoundland, South Georgia, and Antarctica, as well as throughout the Pacific Northwest. His primary area of research is the physiological ecology and conservation biology of seabirds, including the effects of global warming on seabird populations in the Bering Sea.

Rachel Orben's picture
University of California Santa Cruz
Santa Cruz, CA
United States

Rachael Orben has worked almost continuously as a field biologist since graduating from Cornell University in 2002 with a degree in Biology. Working in biology has taken Ms. Orben to locations across the United States, Greenland, Palau, and the Antarctic. She has spent five summer seasons studying seabirds in Alaska, and is currently the field crew leader on St. Paul Island as part of the Seabird Telemetry component of the Bering Sea Integrated Ecosystem Research Program (BSIERP). She is beginning her master's degree at the University of California Santa Cruz in the fall, and when not catching birds, she enjoys rock climbing and playing ultimate frisbee.