The long-tailed weasel lives throughout the United States. It extends from southern Canada all the way down to Mexico and continues south through Central America to northern South America. In South America, it is found in Colombia, Venezuela, Ecuador, Peru and Bolivia. In Ecuador, it lives in the mountains and at the foot of the Andes. This species has the longest range of any other mustelid in the western hemisphere.
It is closely related to the short-tailed weasel that originated in Eurasia and came to North America about half a million years ago.
The long-tailed weasel ancestors developed 5-7 million years ago when forests were replaced by open grasslands. This in turn led to an exploding development of smaller, digging rodents. The ancestors of the longtail were larger than the species is today. The long-tailed weasel originated in North America 2 million years ago.
Vesslan’s small elongated body was perfect for hunting in caves and it thrived well under the snow, so the ice age suited the species perfectly.
The long-tailed weasel is the largest of all weasels. It can be just over half a meter long and weigh 284 grams.
The long-tailed weasel has a typical foot structure, with five toes and a narrow, arched palm on each foot.
They can be active at any time of the day.
The species seems to occur everywhere where there are small rodents. After access to food, the availability of protection is what governs their choice. They thrive in felled forest areas. New grasslands are formed there when the trees are gone. These lands attract small rodents that are hunted by the weasel.
The males acquire a home area of between 1-25 hectares. The females’ territory is much smaller. During early spring, when there are few small rodents, the weasels begin to wander around in search of food. This species has been reported at locations at 1,100 to 4,000 meters above sea level.
It thrives in all environmental zones, from the Alps to the tropics. The only place they do not like is in the desert. Preferably in subtropical, temperate forests in mountain areas.
It thrives in burrows under roots and rocks.
The Long-tailed weasel has a high metabolism, which means that it must eat often. Studies that have been done show that an adult female ate 220 small rodents during a 90-day period in the summer, about two and a half a day.
For the weasel to reproduce successfully, it is necessary for them to settle in an area where there is plenty of food.
In the tropical regions, the food of the long-tailed weasel consists mostly of smaller mammals, rabbits, birds and their eggs. The food varies according to the season, where they live and also the gender. Males usually eat larger prey than females do.
The long-tailed weasel is often considered a pest as they often hunt chickens.
A long-tailed weasel is in general pregnant for 279 days, somewhere between 205-337 days. They get a litter every year consisting of 4-5 newborns, but sometimes it can be up to 9 pups. The eyes are closed when they are born and the coat is not fully developed with a few white hairs. When they are about five weeks old, they open their eyes and start to eat meat when the mother stops breastfeeding them.
They can be found in pairs during the breeding season and during the breeding of the young. Only one in about 90 pups gets older than 2 years.