I. Species Description
Bald Eagles are hawk-like birds that dwarf other raptors. With
an average length of 3 feet and average weight of 9.47lbs. Its
large size appears even larger because of its wingspan which can
range from 70 to 90 inches (5.83-7.5 ft). There is little difference
between male and female except that the females are slightly
bigger. The Bald Eagle uses its large beak sharp talons and keen
eyesight to become apex predators.
Native only to North America, their range encompasses most of
Canada and Alaska, all the contiguous United States, and northern
Mexico. Bald eagles exhibit complex migration patterns
depending on age and location. Many bald eagles are nonmigratory. They are often found in habitats that contain open
water, an abundant food supply, and old-growth trees for nesting.
Typically built below the crowns of mature cottonwoods and
conifers, bald eagle nests can reach 10 ft. in diameter and weigh
up to a half ton.
Their diet consists of fish, small mammals, invertebrates,
reptiles, amphibians. When hunting fish, eagles will plunge
themselves into the water to catch their prey. An opportunistic
species, bald eagles are known to eat carrion, including roadkill.
The average lifespan of a bald eagle is 15-20 years.
The bald eagle is considered an American conservation success
story. Habitat loss, declining prey populations, hunting, and
pesticide use almost drove the species to extinction. Significant
conservation efforts have restored the species, with an estimated
global population greater than 316,000 individuals.
II. Sensitivity to Oil Spills
Bald Eagles are some of the most sensitive and vulnerable
species to oil spills. Direct exposure to oil causes feathers to
separate, impairs waterproofing, buoyancy, and exposes skin
to hyper or hypothermia and lesions. Oil can be ingested
while preening or absorbed through the skin. When plunging
for fish, eagles may cover themselves in oil left on the water’s
surface. Eagles may also ingest oil if they eat from prey or
carcasses that has been covered in oil. This may result in
inflammation, intestinal hemorrhaging, and liver damage,
among other life-threatening conditions. Oiled eagles will
focus all attention on preening and will forgo hunting. This
can lead to other severe conditions such as dehydration,
anemia, and extreme weight-loss. State and Federal wildlife
officials must be notified for response to oiled birds. Oiled
eagles require proper collection, cleaning, and treatment
by certified, state-licensed wildlife rehabilitator at an off-site facility, though temporary processing centers may be
necessary.
III. Sensitivity to Response Methods
The following text describes potential adverse impacts to eagles resulting from various oil spill response methods and/or provides recommendations to reduce impact when these methods are implemented. This is not intended to preclude the use of any particular methods, but rather to aid responders in balancing the need to remove oil with the possible adverse effects of removal with respect to bald eagles. More detail about the response methods themselves can be found in the Inland Response Tactics Manual.