Scientists are baffled by a mysterious illness affecting California brown pelicans along the California coast from San Francisco to San Diego. The symptoms include disorientation, extreme fatigue, and bruises inside the bird’s pouches.
Hundreds of weak pelicans have been running into cars and boats and turning up dead many miles from their normal coastal habitats. The disorientation may imply something is wrong neurologically.
One suspect is domoic acid produced by algae. But domoic acid poisoning, which has reportedly disoriented pelicans in the past, usually occurs in the spring or summer, not in January and has not shown up on any water tests.
Another theory is that the pelicans could have ingested flame retardants used to combat the recent wildfires. Wildlife agencies are still waiting for autopsy and blood test results.
Killed off by the use of DDT in the 1950’s, the California brown pelican was listed as an endangered species. After the pesticide was restricted the species began to recover and the Department of the Interior was proposing to remove it from the list.
The species has proved to be resilient in the past, but bird rescuers are still worried. The LA Times quotes a volunteer with the International Bird Rescue Research Center:
“Pelicans have been hammered over the years by oil spills, DDT, domoic acid, fishing line, gunshots, starvation and parasites — we’re expert at dealing with those problems,” said David Weeshoff, a volunteer at the San Pedro center. “But right now, we’re scratching our heads over the cause of this event. Not a good deal.”