Long-tailed Weasel
Scientific Name: Mustela frenata
The long-tailed weasel is the largest weasel species in New York. It has brown pelage during the summer (with white belly and under chin) and white pelage during the winter except for a few populations in the state that retain their brown pelage year-round.
Adult size: 12-18’’
Weight: 2.5-9.5 oz. Males are significantly larger and often twice the size of females.
Life span: 5 years
Maturity: females breed their first year, while males generally wait till their second year
Litter size: 1-12 (usually around 5)
Fun Fact:
Often described as a voracious eater, the long-tailed weasel eats 20-30% of its body weight every day!
Diet
The long-tailed weasel’s diet largely consists of mice and voles, with a variety of other small mammals (and sometimes larger ones!) consumed including shrews, moles, squirrels, chipmunks, rabbits, hares, invertebrates, frogs, snakes, birds, and eggs. They are a generalist and can shift their diet depending on prey availability.
Habitat
Long-tailed weasels can also be considered a habitat generalist. They use a variety of habitats with high cover and abundant prey. They are more often found at elevations below 2000 ft in woodlands, shrublands, and hedgerows. They may be less abundant in very dense, closed-canopy forests and at higher elevations.
Behavior
They often search for prey in what may appear to be an erratic and hurried pattern scouring the environment for any sign of small rodents. They quickly search every rock crevice, log, and around each burrow in pursuit of prey. They may also climb trees, swim, and burrow in snow. They may cache prey near their burrow for future use. This voracious appetite and uncanny ability to seek out prey occasionally leads them to take domestic chickens or eggs.
The long-tailed weasel may den in old burrows of other animals and maintain several dens throughout their large home range of 75-100 acres. They may be active at any time day or night.
Reproduction and Life Cycle
Individuals are solitary until the breeding season where they form temporary pairs. They breed in July and August and have delayed implantation in females, with most fetus growth in the last month of pregnancy. They give birth the following spring in April or May.
Population Status
stable
Viewing
Their small size, tendency to stay near cover and fast speed make them difficult to spot, but they can be found statewide.
Range
The exact distribution in the state is unknown but they likely occupy most of the state except for densely populated urban regions lacking habitat.
For more information on Long-tailed Weasel in New York please visit the NYSDEC page here.