Pacific Coast sea bird die-off puzzles scientists

January 3, 2015

Scientists are trying to figure out what's behind the deaths of seabirds that have been found by the hundreds along the Pacific Coast since October.

Mass die-offs of the small, white-bellied gray birds known as Cassin's aucklets have been reported from British Columbia to San Luis Obispo, California.

It's normal for some to die during harsh winter conditions, especially during big storms, but the scale of the current die-off is unusual.

"To be this lengthy and geographically widespread, I think is kind of unprecedented," Phillip Johnson, executive director of the Oregon Shores Conservation Coalition, told the Salem Statesman Journal. "It's an interesting and somewhat mysterious event."

The birds appear to be starving to death, so experts don't believe a toxin is the culprit, said Julia Burco, a wildlife veterinarian for the Oregon Department of Fish and Wildlife.

But why the birds can't find food is a mystery.

Researchers say it could be the result of a successful breeding season, leading to too many young birds competing for food. Unusually violent storms might be pushing the birds into areas they're not used to or preventing them from foraging. Or a warmer, more acidic ocean could be affecting the supply of tiny zooplankton, such as krill, that the birds eat.

The U.S. Geological Survey's National Wildlife Health Center in Wisconsin is conducting additional necropsies on dead birds, researchers said.

Robert Ollikainen of Tillamook, Oregon, found 132 dead on the beach there, including 126 Cassin's auklets on Dec. 26. "It was pretty dramatic," Ollikainen said.

Explore further: Federal lab to examine birds believed poisoned

Related Stories

Brown pelicans struggling to survive

February 9, 2010

All along the Oregon coast over the last month, hundreds of brown pelicans have turned up dead, starving or begging for food.

Virus causing mass Cape Cod duck die-offs identified

December 16, 2014

Since 1998, hundreds and sometimes thousands of dead eider ducks have been washing up every year on Cape Cod's beaches in late summer or early fall, but the reasons behind these cyclic die-offs have remained a mystery.

Recommended for you

Coffee-based colloids for direct solar absorption

March 22, 2019

Solar energy is one of the most promising resources to help reduce fossil fuel consumption and mitigate greenhouse gas emissions to power a sustainable future. Devices presently in use to convert solar energy into thermal ...

NASA instruments image fireball over Bering Sea

March 22, 2019

On Dec. 18, 2018, a large "fireball—the term used for exceptionally bright meteors that are visible over a wide area—exploded about 16 miles (26 kilometers) above the Bering Sea. The explosion unleashed an estimated 173 ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Jan 03, 2015
Could be anomalously warm West Coast waters (currently +2 degrees C off Oregon coast), subsequent krill decline, combined with the Aucklet's hunting habits. I think the "more acidic ocean" is global warming spin by the Associated Press.

"The Cassin's auklet feeds offshore, often relying on upwellings of cooler nutrient rich waters and associating with bathymetric landmarks such the continental shelf and underwater canyons. This species unique ability to dive by beating its wings for propulsion allows it to hunt down large zooplankton, especially krill. It can dive to 30 meters below the surface, and by some estimates 80 meters."

"Krill abundance is higher in cooler, more productive conditions and declines in warmer, lower productive environments. T. spinifera is most sensitive to such oscillations in marine climates and essentially underwent a local extinction in Monterey Bay during the 1997/98 El Niño event, but returned in force during the strong subsequent 1999 La Niña event

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.