The long-tailed weasel is a carnivorous mammal of the genus Mustela. Mustela frenata is the scientific name of this small mammal that mainly inhabits southern Canada, the United States, and central and northern regions of South America. Earlier this animal was thought to be nocturnal, like other weasels. But later, it was discovered that though this animal is mostly active during the night, it is also diurnal, as its favorite food item voles are active during the day.
The animal is characterized by a long and slender body and a bushy tail, that is usually more than half of the length of its body. The tail is brown with a black tip. The color of the body is brown above, with yellowish-white underparts.
The adult male can grow up to a length of 14 to 18 inches, and weigh about 500 gm. The female is usually smaller and weighs almost half the weight of the adult male. This short-legged animal has a small head with long whiskers, and a short neck.
In the northern areas, the animal turns completely white in winter, except for the tip of its tail, nose, and the eyes. Such camouflaging help it avoid predators like owls and hawks. When spring approaches, the animal again turns brown with a white or yellowish-white underside.
It is more commonly found in bushy areas, usually near the water bodies like rivers and streams. However, it can survive in a wide range of habitats, including woodlands, farmlands, or open areas. In the United States, the long-tailed weasel can be found in large numbers in the southwest region and throughout Minnesota. Apart from the United States, it can be found in Mexico, South America, and many parts of Canada.
Being a carnivore and aggressive hunter, it preys a large number of small mammals and rodents, like mice, chipmunks, shrews, prairie dogs, rabbits, gophers, rats, mice, and voles. The slender and long body of the animal enables it to easily enter the burrows to hunt down the small rodents. Occasionally, it can also prey on snakes, small birds, earthworms, and insects, like grasshoppers and wasps. It has been observed that this weasel has the ability to attack animals much larger than its size. While attacking a larger animal, it usually rushes at a great speed, grab the base of the skull of that animal, and then crush it with the help of its canines.
Summer is the mating season for this animal. The male reaches maturity in about 1 year, while the female matures in 3 to 4 months. The fertilized egg or the embryo develops only 27 days before the birth of the young. The female gives birth to about 4 to 8 young in spring. The young ones are born blind, as their eyes remain covered with fur. The eyes open in approximately 36 days.
During this time period, the babies are dependent on their mother's milk for survival. Even after they are weaned (about 5 to 6 weeks), their mother continues to feed them and eventually takes them for hunting. Between 7 to 8 weeks, the babies ultimately start to catch prey on their own, and then they leave their mother.
The long-tailed weasel has been found to exhibit some peculiar and distinct behavior. Basically, the animal produces a variety of sounds in different situations. It can squeal, trill, and purr, especially when it is content. But when frightened or alarmed, it can release a strong-smelling musk. The musk is actually secreted by the anal glands of the animal, when it is alarmed or excited, and also during the mating season to attract the members of the opposite sex.
Moreover, this animal has been observed to follow a peculiar zigzag pattern while hunting. Its tracks have a unique appearance due to the fact that the hind legs fall exactly in the tracks of the front legs, when the animal leaps silently. The life span of the long-tailed weasel can be quite short, and many of them can hardly live for one year. However, some of them can live up to 6 years as well. Apart from being a voracious predator, the long-tailed weasel is also a good climber and swimmer. Its main predators are gray fox, red fox, hawks, owls, and large snakes.