Oil seeping from the ocean floor off Santa Barbara is taking a toll on seabirds that are turning up by the dozens along the Southern California coastline coated in crude oil and tar.
The naturally occurring oil bubbles up and afflicts birds every winter, but wildlife rescuers in recent weeks have seen an unusual influx of oiled seabirds stranded on the shore as far south as Orange County, with the region's main rehabilitation center in San Pedro busy treating 140 of them since Jan. 1.
Accounting for most of the increase are common murres, penguin-like aquatic birds from Central and Northern California that spend most of their lives on the water, diving hundreds of feet below the ocean surface to grab small fish and squid.
"The murres have been a new thing for us," said Julie Skoglund, manager of International Bird Rescue's wildlife center in San Pedro. "Over the last three years, we've really seen a lot of them."
Scientists believe the murre population is growing and expanding south, putting the football-sized birds at greater risk of diving into waters slicked by Southern California's oil leaks, the most significant of which are found in the Santa Barbara Channel near Coal Oil Point, where thousands of gallons of oil seep into the ocean each day.
When oil and tar get stuck in the murres' feathers, it eliminates their waterproofing capabilities and makes it difficult for the black-and-white seabirds to float on the ocean surface, dive and regulate their body temperature in the cold water.
The hypothermic, malnourished birds lose energy fast. So they either die offshore or, in an act of desperation, plant themselves on the beach.
"They're literally just bone — there's no muscle on them," Skoglund said. "Typically they're so weak people can walk right up to them and grab them."
And they do.
In recent weeks, beachgoers have found dozens of struggling, oil-stained murres on the shores closest to the major oil seeps in Santa Barbara and Ventura counties and as far south as the Orange County coast.
On Saturday, for instance, a young couple scooped up a murre from San Pedro's Cabrillo Beach, bringing it to the center stuck to a sweatshirt inside a gym bag, Skoglund said.
Some beachgoers have even tried to use soap to wash the birds themselves — a course of action that experts stress could harm the fragile creatures and should be left to professionals.
Murres migrate by the tens of thousands each fall and winter from colonies on California's central and north coast, until recently coming to Southern California only to feed.
That migration pattern appears to be changing.
Last year, researchers discovered a new colony of murres on remote Prince Island in the Channel Islands, marking the first time murre chicks had hatched there since 1912.
"That is a risky little zone there off the Santa Barbara coastline," said Josh Adams, a seabird biologist with the U.S. Geological Survey's Western Ecological Research Center in Santa Cruz. "There's substantial amounts of oil that surface that could pose a threat because of the proximity to the new breeding ground."
Murres, Adams said, are considered more susceptible to oil slicks than other seabirds because of the inordinate amount of time they spend floating on the ocean surface and diving below to feed.
Ocean conditions or an increase in the flow of natural oil also could play a role in this year's hike.
A 2005 incident that injured or killed some 1,500 birds from Santa Barbara to Huntington Beach was linked to an increase in the flow of natural oil leaks.
Tests of the oil found on this year's birds also have confirmed that the oil coating their feathers is from natural seeps, not from any sort of spill.
Though the vast majority of oiled birds found this year have been murres, International Bird Rescue also has treated other shore-based species such as Common Loons, Pacific Loons and Western Grebes.
On Tuesday, workers in rubber aprons and gloves washed oil from the feathers of eight murres found on Southern California beaches.
It's a laborious process to hold down each bird one-by-one and dissolve the oil, spray their feathers with soapy water, sponge, dunk and rinse them, and then dry them off with towels and warm air.
In all, it takes about a week for the center to clean the birds and nurse them back to health.
Not until they have reached a healthy weight and regained their ability to float, dive and repel water will they be released somewhere off the coast of Malibu.
"We want to put them back out in tip-top shape so they're able to thrive," Skoglund said.