Oil causes birds' feathers to mat together into separated clumps. This allows water to seep between the feathers and skin and exposes the animal to the elements. This usually causes birds to freeze to death, but it can also lead to overheating.
Oiled birds instinctively preen their feathers. When they do, the animals ingest toxins that damage internal organs.
The birds' focus on preening also diverts their attention from the essential tasks of eating and evading predators, Holcomb said. If exposure to the elements doesn't kill the birds, long-term health impacts or a predator will.
Millions of small oil spills, primarily from ships cleaning their bilges, go unreported and undetected each year. Such slicks kill hundreds of thousands of birds.
Off the coast of Newfoundland, Canada, for example, some 300,000 birds die from oiling each year, according to Canadian government studies. Off the southern coast of South America, as many as 40,000 Magellanic penguins die from oiling, according to Holcomb.
For birds to survive catastrophic oil spills like the Treasure, well-equipped bird-rescue crews must be mobilized quickly. Human handlers arrive with food and water.
Once the birds are stabilized, the cleaning process begins. The animals are placed in plastic dish tubs and, using a mixture of warm water and a dab of mild soap, rescue workers scrub the birds' feathers. For the eyes and ears, a water pick or toothbrush is used to avoid damaging sensitive organs.
"Really what we're doing is shampooing the birds. We do it vigorously, but they don't like to be handled. So we do it quicklyquickly but efficiently," Holcomb said.
Once scrubbed, the birds are rinsed with warm water, placed in cages with air dryers, andafter they're dryreleased into a pool of warm water.
"They instantly want to bathe, get their feathers in order," Holcomb said. As part of the preening process, the birds rub a natural oil, which is secreted from a gland at the bottom of their tails, over their feathers. The oil acts as a conditioner.
When the birds regain a natural weight and blood values, they are released back into the wild. What happens next, for most species, is an open question. The technology to track wild birds is too invasive to deploy.
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