Researchers trying to calculate how many birds died in the Exxon Valdez oil spill deliberately killed up to 350 more birds this summer, dunked some in oil, fitted all with radio transmitters and tossed them into the sea to track them to their final resting place.
The birds murres, scoters, common eiders, cormorants, ancient murrelets and auklets were collected on islands in Cook Inlet, the Aleutian chain and elsewhere, mostly in national wildlife refuges outside the spill zone. The killing was done by a Portland, Ore. company under contract to the U.S. Department of Justice and the Fish and Wildlife Service.
The $600,000 study is aimed at finding a formula that can be used against Exxon Corp. in court to establish the number of birds killed by the 11 million gallon spill in March 1989.
"The Justice Department felt strongly that this study needed to be done to make its case," said Bruce Batten, a spokesman for the Fish and Wildlife Service in Anchorage.
Although more than 30,000 dead birds were pulled from the oily waters and beaches after the spill, many thousands more were believed to have sunk to the bottom of the sea, been eaten after washing up on shore or been washed out to open waters by ocean currents.
By tracking the movement of dead birds thrown into the water this summer, researchers hope to establish a formula that can used to estimate the total bird loss last year.
If a certain percentage of this summer's study sample washes up on the beaches, for example, the researchers think they can apply that percentage to the number of carcasses found after the spill and come up with a figure for the total spill kill.
"The process of carcass loss both at sea and on the beach face is poorly understood, but it is critical to the estimate of total mortality since this appears to have been the fate of a large portion of the birds killed by the spill," said a partial description of the study released two weeks ago.
While environmentalists contacted about the study Wednesday agreed the results would be useful, they also questioned the government's need to kill more birds to arrive at the formula.
"It's unfortunate they had to collect live birds for the study," said Jack Hession, Alaska representative of the Sierra Club. "It's unfortunate the study wasn't given more publicity so that people could comment."
Al Manville, who follows the oil spill for Defenders of Wildlife, said the study could be challenged because there no longer is any oil on the surface of the water and because many of the predators that would ordinarily eat dead birds on the shore were probably killed by the pollution last year.
"It's necessary to get this kind of information but it is curious that they waited for so long after the fact to get it," Manville said.
No word about the 1990 study was released until a few weeks ago and no environmentalist organizations were aware until contacted by a reporter that birds had been killed for the project.
A description of the study was released about two weeks ago by the federal government as part of a package explaining what oil-spill research had been conducted this year.
But nowhere in the study description was there any mention of the fact that 350 birds were killed to conduct it.
According to the study description, bird carcasses were to be fitted with radio transmitters and put into the water at a number of locations in Prince William Sound and the Gulf of Alaska, the same areas hit hardest by the spill.
R. Glenn Ford of Ecological Consulting, Inc., the company doing the study for the government, declined to answer questions, saying he had been told Wednesday by the federal government to refer all inquiries to the Fish and Wildlife Service in Anchorage.
In order to kill the birds for the study on the wildlife refuges, the company obtained a permit from the Fish and Wildlife Service.
According to that permit, some birds were taken from Chisik Island. That island is part of the Alaska Maritime Wildlife Refuge in Cook Inlet, which on a clear day can be seen from Anchorage.
Hession described Chisik Island as "one of the most important seabird colonies in the state."
The 350 birds sacrificed for the study represent almost half of the 797 birds that the U.S. Fish and Wildlife Service says were retrieved, cleaned and released as part of a highly-publicized bird-rescue program after the spill.
U.S. Fish and Wildlife Service biologists last year did similar experiments with the carcasses of birds killed by the spill. Using data from those studies and other sources, they estimated that between 100,000 and 300,000 birds were killed by the spill, more than were killed by any other spill in history, said Cal Lensink, who co-authored the study. Lensink read a paper on the study at a scientific conference in Cordova this spring.