Brown Bears
Brown bears, also known as Ursus arctos, are
found in extremely small numbers from Western Europe
and Palestine to eastern Siberia and the Himalayan region.
The habitat occupied by brown bears vary a lot, as the
preference may be for desert edges or high mountain
forests and sometimes it may be of ice fields. However,
brown bears usually prefer an area with dense cover,
because they can get shelter by day in such an area.
The Grizzly Bear, Kodiak Bear, Mexican Grizzly Bear,
and Ursus arctos isabellinus are some of the sub-species
of brown bears found in different places.
The brown bears, one of the largest of living carnivores,
are 1 to 2.8 meters long from head to rump, while the
tails are 65 to 210 mm long, and the height up to the
shoulders is between 90 to 150 cm. The weight of brown
bears ranges between 80 to 600 kg, and sometimes more.
However, adult males are larger than the females by
approximately 8 to 10%. The color of the fur is usually
dark brown, but it may vary from cream to almost black.
Brown bears are extremely strong and are able to kill
a cow with a blow.
Brown Bears are nocturnal, and these put on up to 180
kg of fat during summer, which helps for the survival
during the winter season, as in winter brown bears become
very lethargic and prefer to den in a protected place.
However, these are not true hibernators and can wake
easily. Brown bears are also omnivores, i.e., take plant
parts, berries, roots, and sprouts; fungi and fish,
insects, and small mammals as their food.
Brown bears mature sexually between 4 to 6 years of
age and grow until 10 to 11 years. Female brown bears
copulate with multiple males during estrus for 10 to
30 days and males may fight over females and guard them
for 1 to 3 weeks. The mating of brown bears takes place
from the months of May to July. The total gestation
time including pre implantation ranges between 6 to
9 months. January to March are the months for giving
birth to offspring; however, the female brown bear is
in her hibernation during winter season at the time
of birth. In on litter, normally two to three off-springs
are born, and a female breeds every 2 to 4 years.
Brown bears may be active at any time of the day, but
usually they forage in the morning and evening, and
by day they rest in dense cover. Brown bears start hibernation
between October to December and remain such until the
months of January to March. Also, brown bears dig their
dens themselves and make bed out of dry vegetation.
They are usually of solitary nature, and are occasionally
gather in larger numbers at some food sources. Brown
bears have the tendency to travel hundreds of kilometers
to meet the favorable conditions for food and shelter!
Further Reading
Animal Diversity Web
http://animaldiversity.ummz.umich.edu/site/accounts/information/Ursus_arctos.html
|
