Animals

Bear dens vary by locale and conditions. A cave, fallen trees, brush piles, culverts, the base of tree roots, and under buildings all may house the wintering bear. Current research points to reduced thyroid gland activity as the primary motivator for black bears to hibernate, but this is still under investigation. Early researchers believed that the onset of hibernation was due to the snow, temperature changes, decreased atmospheric pressure or a decrease in daylight hours. But a skinny bear will continue to forage in the winter, despite the “rule” that it should be hibernating. That bear might not survive the winter burning up its limited fat supply.
Black bears are not true hibernators like chipmunks and ground squirrels, for example. True hibernators lower their heart and breathing rates to about 10 percent of their normal activity. Black bears lower their body temperature about 10 degrees and their breathing and heart rates decrease slightly.

This is a dark spider overall with a black burst covered by brown hairs. Its legs have orange to dark red-orange “knees” and some smaller patches of orange on the legs. Carapace is usually a creamy beige with a distinctive black square. Can grow to 5 and 1/2 inches in size. A tarantula has two major body sections: the cephalothorax and the abdomen. Appendages on the cephalothorax include four pairs of legs, a pair of pedipalps and a pair of fang tipped chelicerae. (Chelicerae are appendages each of which is made up of a fang and a basal segment containing venom glands and teeth used to macerate prey.) Of the legs, the first two are for holding prey, and the others are used for walking. Mature males have special copulatory organs on the pedipalps and hooks on the first pair of legs. The abdomen has two pair of spinnerets posteriorly.

Males fight viciously for mating privileges during these narrow time windows. Females typically mate with more than one male, often with one from another troop. Gestation is 134-138 days and usually one infant is born, sometimes two if food is abundant. Infants are carried ventrally the first two weeks, then on the back. At two and a half months the infant leaves the mother at times to play, explore and sample solid foods. Final weaning is at 5-6 months. Females in the group with newborns will handle and even nurse other females’ infants as well as attend groups of young as they play. Adult males emigrate periodically and some females are driven out. Life span is 27 years.
Males have fingernail-like wrist spurs which are used to rub on the scent glands of the inner arm and then scar branches and leave scent. They also have “stink fights” in which they face each other and wave tails which have been rubbed on strong-smelling wrist glands.
The palms of this lemur are long, smooth and leather-like, affording a firm footing on slippery rocks, and the great toe is smaller than other, more arboreal species.

Bibliography:
Novak, Ronald. 1999. Walker's Mammals of the World

Head-body length 15-18 inches, tail length 22-24 inches, weight around 6.5-7.75 pounds. Pelage is soft, thick and woolly. Conspicuous black-and-white banded tail. Gray to brown back, white under-parts, a white face with dark brown triangular eye patches and white ears. Eyes are bright red-brown or orange. Face is elongated and fox-like. Females have one pair of mammae. Hindlimbs are considerably longer than forelimbs, giving a hunched, leaning-forward look as they stand or move. Scent glands are present on wrists, arms and chests and are used to mark territory and foraging routes.
These diurnal lemurs start the day soaking up the sun, forage until noon, nap during the hottest part of the day, forage in the late afternoon and evening, and sleep in the trees at night. Ringtails defend resources but are not strictly territorial. Ranges can be15 to 60 acres, depending on the type of habitat and thus the available resources. Troops of 5-24 have non-overlapping territories and disputes usually involve opposing groups of females running at each other and vocalizing. Larger groups form a core group of adult females and infants, juveniles and one or more high-ranking males. Females are extremely dominant and win all disputes with males. Females have dominance relationships, but not dominance hierarchies and there is not always a single, individual leader for the entire group. Even infants grapple for dominance.
Females reach sexual maturity at 2 years of age, have their first young at three years and annually thereafter. Males reach sexual maturity at two and a half years of age, but must contend with older males who will curtail any mating on their part. Mating season is mid-April. Females enter estrous for only a few hours of a single day, although all the females of a group will enter estrous within two weeks of one another.

Bibliography:
Hutchins, Michael, Ed. 2004. Grzimek’s Animal Life Encyclopedia