Carcasses of numerous small, white bellied seabirds known as Cassin’s aucklets found along the Pacific Coast since October are baffling the scientists. The gray colored birds with blue feet which have been washing ashore all the way from Northern California up to the north coast of Washington are worrying experts who are now trying to determine the reason for the mass die-offs.
The University of Washington’s Coastal Observation and Seabird Survey Team has seen more than 1,200 bodies wash ashore since fall began. Diane Bilderback, a volunteer with COASST, a University of Washington citizen science project, had not come across many dead brids belonging to this species till the beginning of fall 2014. A bit farther up the coast, near North Bend, Ken and Cathy Denton have also seeing hundreds of dead auklets being washed ashore.
“We’ve seen a lot of common murres, but those are common,” Ken Denton said. “This is the most we’ve seen of something else.”
Julia Parrish, executive director of the University of Washington’s Coastal Observation and Seabird Survey Team, is worried too. Her primary cause of concern being the fact that the number of the dead birds, according to her, could run into tens of thousands.
Though a majority of the dead birds have been found to have starved to death, the exact cause is not yet known. Different theories are being put forward to explain the possible causes of mass deaths among this small bird.
The birds have been found mostly starved to death, so the deaths are not a result of an oil spill or a toxic reaction to food, said Lindsay Adrean, a wildlife biologist with the Oregon Department of Fish and Wildlife.
Another explanation being offered suggests that the birds could have starved as a result of an unusually successful breeding session last year in British Columbia.
“Almost every breeding pair laid an egg, and as the young birds fly south for the winter they may not all be finding the small fish and shrimp they normally feed on,” Parrish said.
Adrean also suggested that a slightly warmer Pacific over the winter season could have touched off subtle changes in the food chain, making it more difficult for these small sized birds to sustain themselves. Still others are also suggesting unusually violent storms or changes in ocean chemistry as the possible causes.
Robert Ollikainen, a volunteer carcass spotter in Cape Meares, Ore., said he walked onto a low sand bar between Tillamook Bay and the Pacific the day after Christmas and came across as many as 126 dead birds.
He had never seen so many before. “My God, there were so many of them,” Ollikainen said.
It is usual for spotters to come across one or two dead birds along the beach on Oregon. Since the number of the tiny birds being washed ashore is alarmingly high, experts have now begun to take serious note.