PORTLAND, Ore. — When archeologists sifted through the remains of an American Indian village at the mouth of the Coquille River in what is now the city of Bandon, they found the bones of wildlife the village's residents depended on for food, clothing and more.
Sea lion bones were the most common among marine mammals, a cultural staple for Oregon's coastal tribes. But the next most common were the bones of sea otters, outnumbering the remains of the seals and whales more prominent in the ocean today.
"It was pretty surprising," said Roberta Hall, an Oregon State University anthropologist who led the excavations. "The otter was a valuable item. It was a wealth item and was traded for great distances."
It was especially surprising because the wild sea otter--"elakha" to Indians--no longer lives along the Oregon coast.
Now, in the first stage of an effort to return the sea otter to Oregon, Portland State University researchers are focusing a genetic magnifier on otter bones from prehistoric settlements. They want to learn more about the otters that once plied Oregon's shores by the thousands, their valuable pelts fueling early exploration of the region.
The researchers hope to weave information from ancient otter DNA into a detailed picture of the native Oregon otter, once a keystone of the coastal community. In particular, they want to know whether the native otter was more closely related to the northern sea otter, which populates the Aleutian Islands of Alaska, or the southern sea otter, which lives on the California coast--or whether it was some blend of the two.
Scouring the Beach for Genetic Footprint
The aging bones of the native otters hint at their species, but the Portland State team is searching for the genetic blueprint locked within the otters' DNA. The researchers hope to recover the first DNA from prehistoric sea otter remains. From it, they would try to reconstruct the now-hidden family tree of Oregon's long-missing otter, along with a vision of how that tree grew and changed through time.
"DNA adds that much more clarity," said Kim Valentine, a Portland State grad student who will conduct most of the laboratory work for the project, which is to be financed through donations and grants. "It adds light to the picture that you couldn't get any other way."
The blend of archeological, paleontological, biological and even molecular detective work should tell the researchers which modern species of otter would be best suited for the Oregon coast. They also hope such genetic groundwork will help avoid a repeat of a 1970s reintroduction of almost 100 Alaskan otters to Oregon, which failed when the animals all disappeared.
Some scientists suspect those animals might have been a different species, with teeth of a different size and shape, from the original Oregon otter and not as well adapted to life on the Oregon coast.
"It's possible that those just came from the wrong population," said Virginia Butler, a professor of anthropology at Portland State and a leader of the otter project. "There may be characteristics that distinguish the Oregon sea otter, and we'd like to know as specifically as we can what those are."
The sea otter is deeply rooted in Oregon history. Its rich and luxurious pelts were a currency of early coastal commerce.
Such value and prestige carried throughout the world, fueling European exploration and domination of the West Coast. Fur hunters from Russia, Spain, France, England and the fledgling United States had killed more than a million sea otters along the Pacific Coast by the time wagon trains began bringing settlers to Oregon.
When the Atomic Energy Commission planned nuclear tests in Alaska's Aleutian Islands in the 1970s, biologists shipped Aleutian otters to the Northwest, releasing 59 on the west side of Washington's Olympic Peninsula in 1969 and 1970 and 93 otters on the Southern Oregon coast in 1970 and 1971.
Otters eat mainly shellfish such as sea urchins, crabs, clams, mussels and snails, and biologists figured the rocky reefs on Oregon's south coast, like the Olympic Peninsula, represented prime otter range.
Now protected from hunting under the Marine Mammal Protection Act, the reintroduced otters held on in Washington and have multiplied into a population of more than 500. In Oregon, though, the otters disappeared by about 1980.
That puzzled biologists such as Ron Jameson, who tracked the transplanted animals and now works for the U.S. Geological Survey's Biological Resources Division in Corvallis. "My feeling is that most of them were trying to get home, and where they ended up, no one knows," Jameson said. "Maybe they ended up in Washington and joined the population there."