Hundreds of a small, blue-footed seabird called the Cassin’s auklet have been washing up dead on Northwest beaches. So far, scientists don’t know exactly why.
Diane Bilderback is a volunteer with COASST, a University of Washington citizen science project. Until this fall, she had found very few Cassin’s auklets washed ashore.
A bit farther up the coast, near North Bend, Ken and Cathy Denton were seeing similar numbers of dead auklets.
“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.”
All three states are seeing elevated numbers of dead birds. In 2014 COASST counts from Oregon and Washington put the number of dead auklets at more than 800 – the second-highest mortality of all the species recorded. That number is likely much higher since each stretch of beach is surveyed only once a month.
Volunteer counts indicate Oregon's north coast has seen the highest number of Cassin’s auklets wash ashore. Tests by the National Wildlife Health Center show they were young and malnourished and likely died of starvation, not disease or exposure to a toxic substance.
But why now? And why this specific species of bird?
Scientists say the Cassin’s auklet population boomed this year. And it’s the birds that hatched this year that are ending up dead on West Coast beaches.
“New birds are just like any young wildlife, not as good as survival,” said Julia Parrish, COASST executive director.
Young birds are less capable of surviving the winter storms that pound the coast.
“So part of what we think we’re seeing is the aftermath of a really successful breeding year in British Columbia.”
But this is a hypothesis – and one that’s not easily tested because of weather conditions offshore.
For now, Parrish calls the die-off of Cassin’s auklets unusual but not cause for panic.
“We don’t think right now it’s something right now that would seriously impact the population,” she said.
“This has been on and off for two and a half months, and that gives us pause,” Parrish said.