Marine mammal officials consider Kodiak waters as part of sea otter recovery plan
Article published on Wednesday, June 4th, 2008
By RALPH GIBBS
Kodiak Daily Mirror Writer
Move over Steller sea lions, Alaska sea otters are moving in. That’s the word from Douglas Burn, wildlife biologist with the Marine Mammals Management Office.
Burn was in Kodiak this week to talk to Kodiak residents and the North Pacific Fishery Management Council on where the Marine Mammals Management Office is in the process to designate critical habitat for sea otters by an Oct. 1, 2009, court-ordered deadline.
The sea otter was placed on the threatened species list Aug. 9, 2005, marking the second time in their history sea otters have been threatened with extinction.
The first time was around the turn of the 20th century, when they were nearly hunted out of existence by fur hunters. The otters made a comeback after the International Fur Seal Treaty was signed in 1911.
Over the course of the 20th century, the sea otter population soared to several hundred thousand, but during the last several decades, the population has once again been dwindling and is now estimated at around 10,000.
An article published in the 1998 issue of Science Magazine, by Jim Estes, M.T. Tinker, T.M. Williams and D.F. Doak, said, “We first detected this decline through population surveys at Adak Island in the central Aleutian archipelago, which indicated that the otter population decreased (approximately) 25 percent per year though the 1990s, resulting in nearly an order-of-magnitude overall reduction by 1997.”
Although there are several theories, the most widely accepted theory was put forth by Estes.
“Increased killer whale predation is the likely cause of these declines,” Estes wrote. “Although killer whales and sea otters have been observed in close proximity for decades, the first attack on a sea otter was seen in 1991. Subsequently, nine more attacks have been reported.”
Estes thinks the reason killer whales turned to otters as a food source might be the decline in Steller sea lion and seal populations.
Now, the Marine Mammals Management Office is tasked to develop critical habitats to help sea otter recovery. Aleutian Islands and Kodiak waters will be considered.
Bycatch from commercial fisheries is another threat to sea otters. To end bycatch in California, the Center for Biological Diversity teamed with the Turtle Island Restoration Network and sued the California Department of Fish and Game. In 2000, California Fish and Game shut down a set-net fishery and effectively banned gillnet fishing in the Monterey Bay National Marine Sanctuary.
“What exactly is a critical habitat?” Burn asked. “It’s defined as the physical and biological features essential to the conservation of the listed species. Some of the examples they give are space needed for population growth, food, water, air, light, minerals and shelter.”
Burn said the Marine Mammals Management Office is looking at cover and shelter as the most needed aspect for sea otter critical habitat.
“About 50 percent of otters are within 10 meters or less from the shoreline,” Burn said. “About 95 percent are within 100 meters. In fact, when we’re out surveying now, if we come to a place the chart says it’s rocky, fouled with wodges, lots of kelp, and there’s all kinds of navigational hazards, we can pretty much bet there is going to be a sea otter in there somewhere.”
The criteria Marine Mammals Management Office is using to determine critical habitat includes shallow rocky areas, kelp forests and near-shore waters.
“In the recovery plan, we’re going to propose five management units. The Western Aleutian, which is the longest, the Easter Aleutian, the South Alaskan Peninsula, Bristol Bay and this one here, which is a grab bag.”
That grab bag includes Kodiak.
However, the management areas may change and will be limited to approximately 20-meter depth areas.
“The 40-meter depth contour is considered to be the prime sea otter habitat,” Burn said. “Within this prime sea otter habitat definition we said the 20-meter depth contour is the criteria that will encompass those features that are really essential for their conservation, features that provide cover and shelter. If you go out to 40 meters, you no longer have those features that provide cover and shelter.”
He said that many of the 20-meter subunits would fall within areas that are already designated Steller sea lion habitats, so the effect will be minimal.
“No land above mean high-tide line will be included in this definition,” Burn said. “Nearly all the sea otter critical habitat is going to occur in State of Alaska waters. The majority of the critical habitat is adjacent to federal lands, most of which is National Wildlife Refuges and National Parks.”
Burn said the designation shouldn’t affect villages.
“There are provisions within the act for excluding areas from the critical habitat,” he said. “Once we have a pretty good idea of where the lines are drawn on a map, we do an economic analysis. It turns out that areas within 1 to 5 miles of all the populated communities is 0.2 percent within 1 mile, 0.8 percent within 2 miles and about 3 percent or so within 3 miles.”
The Marine Mammals Management Office is expected to present the proposal to the federal register Nov. 30, 2008, and is open to public comment during that time.
Mirror writer Ralph Gibbs can be reached by e-mail at email@example.com.