Sea slime killing seabirds off Oregon and Washington

11/05/2009

Wildlife rescue teams wash sea slime off a loon Photo Courtesy Paul Kelway/IBRRC

Thousands of seabirds have now died in the Pacific Northwest over the past several weeks, in a near repeat of what occurred in California’s Monterey Bay in November 2007. The cause? A strange foamy sea slime has covered stretches of ocean, coating seabirds’ feathers, and leaving them vulnerable to death by hypothermia and predators. Seabird feathers have natural water resistance but in the case of oil, or in this case seafoam, it coats them with a substance similar to soap, compromising their feathers' natural waterproofing ability.

In mid-September birds started washing up on Washington’s Olympic peninsula. Around one thousand scoters, or sea ducks, died at that time. Biologists thought it was over, but then it started up again in October, reaching all the way down from Washington to Cannon Beach, Oregon. The dead and dying birds include common murres, common loons, red-throated loons, and grebes.

Volunteers and biologists from several organizations have rescued as many birds as possible before they succumb to hypothermia. Over 500 have been cleaned and sent to the International Bird Rescue Research Center (IBRRC) in Fairfax, California which specializes in helping seabirds survive oil spills, though this seafoam has a natural cause. Scientists have identified the same dinoflagellate in the Oregon and Washington seafoam that caused the Monterey Bay situation - Akashiwo sanguine - which causes a red tide event.

"A. sanguinea is a naturally occurring algea along the Washington coast, however this fall it's concentrations were much higher than normal," explains Penelope Chilton, Research Coordinator for COASST (Coastal Observation and Seabird Survey Team), a network of volunteers that collects data on seabirds. "The interesting thing about this particular dinoflagellate is that when it is churned up in heavy surf the hard outer shell breaks open releasing a surfactant that is then whipped up into essentially a coastal bubble bath." Many red tide events kill marine life directly through toxins, but in this species, there’s no toxin but the sea slime from the surfactants kills birds by coating their feathers.

Though initial funding to rescue the birds came from some government agencies, as well as Petco Foundation and the Oregon Humane Foundation, private wildlife organizations such as IBRRC will end up paying the bulk of costs to care for, feed, rehabilitate and release the birds. They welcome donations.

The U.S. Coast Guard flew 305 of the birds from Astoria, Oregon to Sacramento, California where workers from IBRRC rushed them to the San Francisco Oiled Bird and Education Center, co-owned by IBRRC and Oiled Wildlife Care Network. In a tragic turn of events, the same Coast Guard C-130 plane that flew the birds collided with a marine helicopter, and crashed off of San Diego. Though they were not on a bird rescue mission at the time, it held one of the pilots that helped with the birds along with six other crew. No survivors have been found.

Back in 2007, biologists had no idea what caused the yellow-green soapy slime in Monterey Bay. A huge team of scientists worked to identify the cause, led by the California Department of Fish & Game’s David Jessup and including scientists from Monterey Bay Aquarium Research Institute (MBARI), and Moss Landing Marine Laboratories (MLML). They published the results in the online journal PLoS ONE. According to one of that study’s co-authors Raphael Kudela, professor of ocean sciences at the University of California, Santa Cruz, big red tide events have started increasing in frequency, especially since 2004. Global warming has caused ocean temperatures to rise, which may contribute to the increase in red tides, as well as other bizarre mucus blobs occurring throughout the ocean.