62 Nebraskaland • April 2020
By Julie Geiser
BIRD OF A DIFFERENT COLOR
While out taking photos one morning, I came across a
strange-looking bird. From a distance, I couldn't tell what
the bird was. Curious, I slowly closed in and snapped photos
of it until I could see it was a partially leucistic, or piebald,
American robin.
Many bird and mammal species can display leucism, which
is a condition where there is a reduction of pigmentation
resulting in white, pale or patchy colors of skin, hair, scales or
feathers. In birds, leucism only affects the feathers, and the
degree of leucism varies, depending on how pigment cells
were defected during an animal's development.
The plumage of leucistic birds appear paler than normal
because there is a reduction in all types of pigmentation.
Some birds may show irregular patches of white among
normal colored feathers, which results in pied, or piebald,
leucism. Other leucistic birds may have no pigmentation at
all in their feathers, making them look pure white; however,
this does not mean that the bird is an albino.
Albinism affects all the pigments in an individual, not
just in spots like the American robin I photographed. Albino
birds show no color whatsoever in their feathers and have
pale-pink or reddish eyes, legs, feet and a pale bill, whereas
leucistic birds often have normally colored eyes, legs, feet
and bills.
There are some downfalls to white feathers. These feathers
can wear out faster than darker colored feathers due to their
lack of melanin, which is a structural component of feathers.
Weakened feathers may make flying more strenuous, and
white feathers reflect heat, making it tricky for the bird to
keep warm in cold temperatures. Lastly, white plumage is not
good camouflage for birds that depend on it to keep safe from
predators, such as cats, foxes and hawks.
Identifying leucistic, or piebald, birds can be challenging
but the majority of these birds will possess other normal
plumage colors that can be used for identification. While
the white feathers on the American robin I photographed
were perplexing, its normal colors made identification less
difficult. Examining a leucistic bird's size, shape, range and
behavior, and taking note of other birds nearby, can also aid
you in identifying the species.
THE LAST STOP
PHOTO
BY
JULIE
GEISER
