... and even white.
would black bears be different colors if they are all the same species?
the causes are not perfectly clear, there is evidence to suggest that
coat colors vary as a mechanism of camouflage or due to climate and
habitat. Bears in moister, more densely forested regions tend to be
black, while bears in the West, where conditions are drier and vegetation
is sparser, tend to be brown or cinnamon. A black coat allows the bear
to blend into the shadows created by dense trees and brush, and a brown
coat blends better with the sandier, browner landscape. In addition,
black retains heat far more than does a lighter color, so brown phase
bears are less susceptible to heat stress in more open terrain. The
surface temperatures of a black bear's fur can heat to 180 degrees Fahrenheit
in the direct, hot, summer sun. Finally, there is evidence to suggest
that melanin, the pigment responsible for the black coat color, is more
resistant to abrasion, thus it would be advantageous to those bears
living in heavily forested regions. Only 1% of the black bears in Pennsylvania
are brown or red in color, while over 90% of the black bears in Yosemite
National Park in California are tan, light brown or cinnamon.
the Kermode bears of British Columbia albinos?
the "spirit bears" of British Columbia are not albinos but simply another
color variation. If they were albinos, they would lack color pigment
in their eyes and skin as well as in their fur. While exceedingly rare
and primarily isolated to a few islands off the coast of British Columbia,
these white bears are as normal and healthy as any black-colored black
bear. Their color arises from a mutation in a particular chromosome
that is responsible for coat color. The mutation did not prove lethal
to the individual(s) who initially carried it, so it remained in the
"genetic" population. Since island populations are isolated, breeding
occurs in a rather small circle of individuals, thus passing the gene
more quickly than would otherwise occur. This allowed the gene to become
prevalent, and now one in every ten cubs born on these islands is white
in color. A black sow can give birth to a white cub, and visa versa.
In fact, cubs of a variety of colors can occur in the same litter. In
1997, a white bear was seen at the Vince Shute Wildlife Sanctuary. Although
he was not a Kermode bear, his appearance was very similar to that of
the "spirit bears." Click here to learn
more about this amazing animal.
is the rarest color phase of American black bears?
is the rarest color phase, a very uncommon and particularly beautiful
color phase of the black bear is the blue-gray or glacier bears of southeastern
Alaska, northwestern British Columbia and the southwest Yukon. The
undercoat of the glacier bears is a rich blue-black, while the outer
guard hairs are long and white (or light yellow) with silver tips.
This color variation probably evolved during the last ice age when populations
were isolated along the unfrozen sections of the coastline, due to the
biological process of genetic drift (random fluctuations in the genetic
composition of a small population). The blue-gray color is ideal camouflage
against the backdrop of frozen ice - the bears are nearly impossible
to spot unless they are moving. Unfortunately, this color phase is
on the decline. Immigration of non-glacier black bears and emigration
of glacier bears across the now unfrozen landscape, are causing the
gene frequency to be eliminated in the face of more dominant color phases,
as the two mingle and mate.
do some bears have different colored markings on their chest?
on the chest, commonly called a chest blaze, can be a variety of shapes
and sizes and are white or light brown in color. Not all bears have
chest blazes. They can consist of a small dash, a deep V, or a "patch".
While there is no way to be certain, the current theory is that these
chest blazes are used for communication and identification among the
bears themselves. 80% of all cubs are born with chest blazes, but many
lose them as they age. If the mother has a blaze, the cub is more likely
to retain theirs throughout its lifetime.
does a bear's coat look different in the summer?
molt annually in the early summer. They shed both their underfur and
outer guard hairs, leaving only a short, sleek summer undercoat. Each
individual molts at a different rate and in different ways. Some bears
will molt from the face backwards, while others do so in a more helter-skelter,
all-over pattern. Their new coat is growing in as the old one is being
shed, so that by fall they have their thick, luxurious coats once again.
bears' coats change color?
a bear's coat can change color - from brown or cinnamon to black. This
generally happens in the juvenile or sub-adults years. Changes seen
in older bears are usually attributable to bleaching, where the tips
of the hairs are lighter than the base.