Oil can be lethally harmful to waterbirds – particularly to diving birds that spend a great deal of time on the surface of the water where the oil sits.

Oiled wings can kill birds.
Oiled wings can kill birds. (See larger Courtesy San Francisco Chronicle

When there is an oil spill, it’s impossible to know in advance how many birds will be impacted. International Bird Rescue works with local state and federal biologists to look at what animals are in the area at the time of a spill and try to determine what species and how many of them may be exposed to oil.

When oil sticks to a bird’s feathers, it causes them to mat and separate, impairing waterproofing and exposing the animal’s sensitive skin to extremes in temperature. This can result in hypothermia, meaning the bird becomes cold, or hyperthermia, which results in overheating. Instinctively, the bird tries to get the oil off its feathers by preening, which results in the animal ingesting the oil and causing severe damage to its internal organs. In this emergency situation, the focus on preening overrides all other natural behaviors, including evading predators and feeding, making the bird vulnerable to secondary health problems such as severe weight loss, anemia and dehydration. Many oil-soaked birds lose their buoyancy and beach themselves in their attempt to escape the cold water. The fortunate ones are taken in by concerned citizens or capture crews.

Pelican from Gulf Oil Spill in 2010: Before and after cleaning
Pelican from Gulf Oil Spill in 2010: Before and after cleaning

Bird feathers are naturally waterproof, but to maintain this, each feather must be aligned properly so that water cannot seep through the microscopic barbs and barbules that are part of the vane of each feather. These barbs and barbules hook together like Velcro to form a tight waterproof barrier. Each properly aligned feather overlaps another like the shingles on a roof to create an entire waterproof covering for the bird. It is the bird’s job to maintain its feather structure. While preening, birds distribute natural oils, which help in the long-term maintenance of feathers by keeping the feathers supple so alignment can be maintained.

Properly aligned feathers will not allow water or air to penetrate and ensure that the bird is buoyant and insulated from the cold. Every day birds spend considerable time preening because if their feathers are not perfectly aligned, it could kill them.

With proper vet treatment and good facilities, oiled birds can be stabilized, fed and when ready, can be washed by experienced wildlife rescue personnel.

During the 2010 Gulf Oil Spill off the Louisiana coastline, hundreds of birds were saved using these protocols. One particular Brown Pelican was imortalized in the 2011 HBO documentary Saving Pelican 895. See the trailer and our blog post on the West Coast film opening.