Washington, DC -- Northern fur seals have experienced major changes in their behavior, ecology, and geographic range of over the past 1,000 years, according to a new study appearing in the May 21 early online edition of The Proceedings of the National Academy of Sciences.
Using techniques from archaeology, biochemistry, and ecology, a team of researchers* has reconstructed the species prehistoric geographical range. Among other results, the scientists found that the northern fur seals reproductive behavior was very different in the past than it is today.
"We were able to see changes in biogeography and behavior over time scales longer than ecologists usually think about," said lead author Seth Newsome, a postdoctoral researcher at Carnegies Geophysical Laboratory who performed much of the work as a graduate student at the University of California, Santa Cruz.
Today, the main breeding colony of northern fur seals is on the Pribilof Islands in the Bering Sea. But the species once had major breeding colonies at more hospitable latitudes in California, the Pacific Northwest, and the eastern Aleutian Islands. Their bones are abundant in archaeological sites in these regions, suggesting that they were prevalent in local marine ecosystems and also that they were important to human cultures. Prehistoric northern fur seals also nursed their young for much longer than modern fur seals, which wean their pups just four months after birth.
Newsome said the study is important because fur seals and many other species were decimated by commercial harvesting long before scientists were able to study them first hand. "What we consider natural for a species may not have been its natural state prior to human disturbance," he added.
The disappearance of northern fur seals from some temperate regions coincided with the arrival of Russian and European fur traders about 200 years ago. But in central and northern California, fur seal popu
Contact: Seth Newsome