Biology Reference
In-Depth Information
bear single calves. Cows from ages four to nine are considered to be the prime breeders, and about 40
percent of those cows have twins. Triplets occur, but are rare.
The calves weigh twenty-five to thirty-five pounds at birth. Although their long legs are wobbly at
first, they can follow their mother around after only three or four days. Like whitetails, moose have
very rich milk, so the calves gain weight at a phenomenal rate. They put on a pound a day for the first
month and two pounds a day for the next three or four months. As a result, these huge “babies” often
weigh three hundred pounds or more by December—far more than most mature whitetails. Although
the calves can survive on their own after two months if something happens to the cow, they normally
continue to nurse until October. By the following October, the year-old moose will weigh a remarkable
four hundred to six hundred pounds!
Summer food for moose is quite different from their winter fare. Because of a winter diet consisting
almost exclusively of browse, moose emerge from the long winter months deficient in sodium and cer-
tain other elements. To remedy this lack, succulent aquatic plants now become an important part of
their diet. These plants are rich in sodium, iron, and other nutrients, and moose begin to feed on them
eagerly as soon as they become available.
Good moose habitat contains plenty of wetlands—shallow, boggy lakes, beaver ponds, and similar
areas. These serve a dual function: first, they provide a rich source of aquatic plants for food; second,
they keep the moose cool in hot weather and offer some relief from the hordes of biting insects that
torment them at that time of year.
Moose are powerful swimmers, so at home in the water that they might almost be called semiaquatic
during the summer months. They have hollow hairs that provide considerable buoyancy, so, despite its
great bulk, a moose has little difficulty staying afloat. Most of a moose's aquatic time, however, is spent
wading in relatively shallow water, where it can submerge head and neck in order to bring up favored
plants to be munched above the surface.
Thanks to this trait, my wife and I had a memorable experience with a moose. We were canoeing
the shoreline of a pond, looking for moose while the September dusk was starting to settle. Suddenly
we began to hear what sounded like a waterfall, although we knew there were none nearby. Moreover,
the sound was sporadic, rather than the steady noise made by falls. Suspicion dawned on us, and we
paddled hurriedly toward the source of the sound, along the far shore some distance behind us.
Sure enough, there was a huge bull moose, one of the largest we've ever seen. Although he was
deeply engrossed in feeding and paid no attention to us as we approached, we maintained the properly
respectful distance befitting such a forest monarch. Each time he raised his head from beneath the wa-
ter, his mouth stuffed with plants, water cascaded off the wide palms of his majestic antlers, temporarily
imitating the sound of a miniature waterfall.
One of the most misunderstood aspects of moose biology is their interaction with deer. Over and
over, the refrain is heard in some circles, “Moose drive out the deer.” When people correctly observe
that there are more moose and fewer deer in a particular area, they frequently make the erroneous as-
sumption that this is a clear case of cause and effect. It isn't.
