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| An
oiled Gannet just before being rescued at Prestige
oil spill.
This bird and thousands of
others
were affected by a tanker spill off the Spanish
coast in late 2002. (IFAW photo) |
Just little bit of oil can be deadly
Did you know that
a seemly harmless dime-size glob of oil could kill a bird?
We may learn about the devastating effects of spills that
occur when tankers accidentally loose their cargo, but there
are thousands of small spills occurring daily around the world
that go unreported and unnoticed. Millions of water birds
die every year due to oil from a plethora of sources, from
jet skis and motorboats, to oil washed off streets and into
storm drains after rain.
When you look at a bird covered in oil it is difficult
to imagine how it could ever be cleaned, much less survive.
It used to be thought that washing a bird with soap would
remove the natural oils from its feathers, causing the bird
to loose its insulation and waterproofing, which would lead
to its death. It's true that birds have an oil producing gland,
and when they preen they spread this oil on their feathers,
but it is only a conditioner.
What keeps birds waterproof is the position of
the feathers. What a bird is doing when it preens is carefully
aligning each feather, which is made up of a shaft, veins,
and tiny barbs that connect the veins into a tightly woven
unit. This feather structure does not allow water or air to
penetrate and provides buoyancy and insulation.
The feathers overlap each other like the shingles
on a roof to create an entire waterproof covering for the
bird. Properly aligned feathers will not allow water or air
to penetrate and ensures 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
literally mean death.
When a bird encounters oil on the surface of the
water, the oil sticks to its feathers, causing them to mat
and separate, impairing the waterproofing and exposing the
animals 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. This ingestion can cause
severe damage to the bird's internal organs. The focus on
preening overrides all other natural behaviors; including
feeding and evading predators, making the bird vulnerable
to secondary health problems such as severe weight loss, anemia
and dehydration. Many oil soaked birds loose their buoyancy
and beach themselves in their attempt to escape the cold water.
The fortunate ones are picked up by concerned citizens or
capture crews.
|
A penguin tries to preen the oil out
of its feathers at the Treasure Oil Spill in
South Africa. Photo © IFAW |
The birds that are brought to rescue centers
are often frightened, cold, emaciated, dehydrated, exhausted
and
suffering from the internal effects of oil. Initial procedures
may involve cleaning the eyes, nasal and oral passages of
oil and dirt, applying saline eye solution, giving
oral fluids and activated charcoal solution, but not washing.
To wash a bird that is already highly stressed
and not medically stable could mean death. Many oiled bird's
die because well-meaning people, anxious to get oil off the
bird, wash it immediately, resulting in death from stress.
It is actually more important to give oiled birds the much
needed nutrition, hydration and medical treatment they need
before they are washed.
Once stable, oiled birds go through a series
of tub washes alternating between baths with a one percent
solution of Dawn dishwashing liquid and clean water. The
wash time varies depending on the amount of oil, and the
size of the bird, but on average it takes two people 45 minutes
and 300 gallons of water to do a thorough washing.
After being washed, the birds are put in net
bottom cages with warm air dryers. The final steps are to
put them in warm water pools, where they continue to preen,
and finally into cold pools. Birds in rehabilitation are
checked constantly to make sure that they are completely
waterproofed and when their blood work and weight are in
the normal range, they are banded and released.
We thank Procter and Gamble for the countless
donations of Dawn dishwashing liquid that they have contributed
over the years.
Also on this site:
Rehabilitating
oiled birds
Pelicans:
Before and after photos
Or see these links:
Oil
pollution and birds
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