 |
Muskox
Behaviour
Muskoxen are gregarious
animals and live in loosely organized herds. Herd size and composition
vary with season, range conditions and the number of bulls in the
population. An average herd is about 15 animals. After the rut in July and
August, the herds increase as bulls and/or mixed groups join together. The
presence of wolves may cause an increase in herd size in response to
harassment. Some groups of muskoxen may merge together for feeding, while
in severe winters large herds may fragment as a result of limited forage.
 Unlike caribou, muskoxen do not undertake long migrations, but in some
areas, such as near Coppermine, winter and summer ranges are distinct and
as much as 160 km apart. On treks between ranges, a dominant bull or cow
leads the group.
The
dominant bull is usually one of the largest animals in the herd. He will
likely have large, dark coloured, cracked horns, and clinging to his coat
in summer will be a great deal of unshed wool. When the dominant bull
walks through the herd, subordinate animals move out of his way and stand
watching. When danger threatens, the dominant bull is often the last
member of the herd to respond and the first to relax when all is clear. In
all-cow herds, a cow may display the same characteristics of leadership.
The
influence of the dominant or lead animal is shown most clearly when a herd
encounters some obstacle such as a deep river or steep bank. While other
herd members mill about, the dominant bull appears to take the situation
in hand and leads the others past the obstacle. In cases of disturbance
from man, machines or wolf attack, the dominant bull again takes charge.
At
the approach of wolves the herd often runs towards high ground or to an
area of shallow snow. At the top of the high ground, the dominant bull
stops and turns to face the threat while other herd members close ranks
behind him in a characteristic defence formation. Animals shuffle and
agitatedly change position while they watch their foe. Such a formation is
extremely effective against wolf attack as long as no animal allows itself
to become separated from the line of defence. Wolves will circle the herd
and attack individual animals that charge out. If the herd is well
organized, the wolves will eventually give up to search for easier game.
However, if an animal does become separated, or if wolves encounter a lone
animal, its chances of survival are considerably lessened.
Normally a full-grown muskox is formidable prey for a wolf and can easily
defend itself by charging with its horns. But if the wolves begin worrying
the muskox with intermittent attacks it becomes increasingly tired and
vulnerable. Eventually, unless it can break away, it will likely fall
victim to the wolves.
|
