Friday, January 09, 2009

Brown Pelicans Showing Up Dead in California

Over the past few weeks, brown pelicans have been showing up disoriented and malnourished on busy freeways, neighborhood backyards and even a Costco parking lot miles from the ocean -- and those are the lucky ones.

Reports are coming in from Baja California to Oregon of hundreds of pelicans found dead along the coastline for unknown reasons. Scientists and biologists are scrambling to determine what is killing the prehistoric-looking birds.

More than 20 have been found dead or dying in Ventura County, Calif. alone since Christmas.

"This is unusual," said David Caron, a biological sciences professor at the University of Southern California, who will be doing blood work on injured birds. "When we have one of these mortality events, it's a significant hit to the population."

Large numbers of pelicans sometimes die because of a naturally occurring toxin called domoic acid, but these latest victims do not seem to have the usual symptoms, and no other animals in the marine ecosystem seem to be affected. Although domoic acid is not being ruled out, such outbreaks usually occur later in the year, and birds and other animals have seizures because of neurological damage.

"We've seen enough to imply that something is odd, and right now it is a big question mark what it is," said Jay Holcomb, executive director of the International Bird Rescue Research Center, whose offices in northern and southern California have received more than 100 sick birds since the new year.

What concerns scientists, beyond not knowing the cause, is that a large number of adult pelicans are showing up emaciated and with discolored pouches at the oddest of places.

"I've got them from the Costco parking lot in Goleta and the Kmart parking lot in Lompoc," said June Taylor, who works with seabirds for the Santa Barbara Wildlife Care Network. "I get reports every day of dead pelicans on the beach. I've never seen anything like it."

Since Dec. 20, she has cared for more than 50 birds from Ventura and Santa Barbara counties, she said. She got a report of a dead pelican in the Ventura Harbor on Tuesday and has heard of other dead ones near Surfers Point in Ventura. Rehabilitation centers like hers are quickly becoming overwhelmed by the birds, which can have a wing span of more than 6 feet.

The large die-off comes less than a year after biologists celebrated pelicans being taken off the endangered species list. Years of exposure to the pesticide DDT had caused the birds' eggs to thin and collapse during nesting. In 1970 on Anacapa Island, the largest pelican nesting colony in California, only one nest successfully hatched an egg. Now the island has about 4,500 active nests a year.

"Poor pelicans, they can't catch a break," said Karen Hughes, a volunteer with the Wildlife Care Network who has been picking up sick birds in Ventura County for weeks. Her garage has been converted into a makeshift way-station for the birds, where she helps them get warm or rehydrated before transferring them to official rehabilitation centers. Most of the pelicans, however, are dying a few hours after she finds them, she said.

There are numerous theories about what could be happening. Taylor said it could be a toxin, such as fire retardant, running off the land and into the water.

Dan Anderson, an ecotoxicologist and avian ecologist at UC Davis, has only seen something like this once or twice in his 35 years of studying pelicans. He said it could be a disease, or a toxin in the water or food the birds are consuming.

Caron said the birds could have been affected by domoic acid in the past and suffered brain damage.

Some new trigger in the environment, such as cold weather or another disease, could be exacerbating the previous damage.

"It will take some detective work," he said.

Meanwhile, rehabilitation centers are working nonstop to save what birds they can.

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