In the storm debris littering a Washington State shoreline, Bonnie Wood saw something grisly: the mangled bodies of dozens of scraggly young seabirds. In the storm debris littering a Washington State shoreline, Bonnie Wood saw something grisly: the mangled bodies of dozens of scraggly young seabirds. Walking half a mile along the beach at Twin Harbors State Park on Wednesday, Wood spotted more than 130 carcasses of juvenile Cassin’s auklets—the blue-footed, palm-size victims of what is becoming one of the largest mass die-offs of seabirds ever recorded. “It was so distressing,” recalled Wood, a volunteer who patrols Pacific Northwest beaches looking for dead or stranded birds. “They were just everywhere. Every ten yards we’d find another ten bodies of these sweet little things.”

Cassin’s auklets are tiny diving seabirds that look like puffballs. They feed on animal plankton and build their nests by burrowing in the dirt on offshore islands. Their total population, from the Baja Peninsula to Alaska’s Aleutian Islands, is estimated at somewhere between 1 million and 3.5 million. Last year, beginning about Halloween, thousands of juvenile auklets started washing ashore dead from California’s Farallon Islands to Haida Gwaii (also known as the Queen Charlotte Islands) off central British Columbia. Since then the deaths haven’t stopped. Researchers are wondering if the die-off might spread to other birds or even fish.

“This is just massive, massive, unprecedented,” said Julia Parrish, a University of Washington seabird ecologist who oversees the Coastal Observation and Seabird Survey Team (COASST), a program that has tracked West Coast seabird deaths for almost 20 years. “We may be talking about 50,000 to 100,000 deaths. So far.” Although there doesn’t appear to be a link to the virus that killed tens of millions of sea stars along the same shores from California to Alaska over the past 18 months, some scientists suspect a factor in both cases may be uncharacteristically warm waters. The U.S. Geological Survey and others have performed animal autopsies, called necropsies, on several of the emaciated Cassin’s auklets. FULL REPORT