Sometime between the last half of January and the first part of February, black bears give birth to between one and five (usually two) tiny, blind, almost hairless cubs. Measuring about 9 inches long and weighing in at roughly one-half pound, each cub is about the size of a chipmunk. For the next few months, the cubs will be totally dependent on their mother for food and warmth.
Most dens are exposed to the cold air, as they are located under fallen logs and brush, or are dug into a bank. Occasionally dens are on the ground with little or no cover. In all of these locations, the mother acts like a furnace, enveloping her young and breathing on them to keep them warm. Newborn cubs do not hibernate, but nap frequently. Like human mothers, black bear mothers sleep when their young sleep, and are alert when their cubs cry to indicate that they are in need of attention.
This photo, of a 2-month-old cub and its mother, was taken in March, as New Hampshire Fish and Game officers and independent wildlife biologist Ben Kilham were checking on a den. Kilham operates the Kilham Bear Center in Lyme, New Hampshire, a licensed rehabilitation center that has raised hundreds of orphaned, abandoned, and injured bear cubs for release to the wild.