Natural Histories

photograph of a Sunda Pangolin

Short-tailed weasel or Ermine

Mestela erminea


This species can be found in the north temperate regions of Eurasia and North America. The short-tailed weasel is 7-13 inches long, intermediate in size in comparison to other North American weasels. Males are typically twice as large as the females. Short-tailed weasels have long bodies, short legs, a long neck, a flattened triangular head, round ears and black eyes. In the summer their fur is dark brown with white under-parts and white along the inside of hind legs and feet. The tail of this species is only 35% of their total body length. They have a distinctive black tip on their tail. During the winter this weasel molts into a completely white fur coat with a black tip to the tale and is commonly referred to as an ermine.


This species is well adapted to snowy environments and can be found in grasslands, wetlands, farmlands and prefers brushy or wooded areas near water with high densities of small mammals. They do not typically live in dense forests. They build their dens in burrows under stumps, rock piles, or old buildings. The short-tailed weasel builds a nest within their burrow, line it with dried vegetation and the fur and feathers of prey. They also dig side cavities from their burrows that are used as food caches and latrines.

Feeding Behavior and Diet

The short-tailed weasel is a carnivorous species and consumes small mammals, eggs, frogs, fish, birds and insects; they are particularly good at hunting voles. In the winter this species can hunt under the snow, tunneling, and also running on top of snow. They hunt by leaping in a zigzag pattern, each leap of about 50cm. They approach their prey as closely as possible and quickly grab the back of the head with sharp teeth, wrapping its prey with its body and feet while biting repeatedly at the base of the skull.


Short-tailed weasels are polygynandrous/promiscuous (meaning that both males and females will have more than one breeding partner) breeding during the spring and early summer. The total gestation period for this species is 280 days, including a delayed implantation, before the female gives birth to 4-13 young between April and May. By three weeks the young have a dark mane of dense fur around their neck. After 8 weeks the young are able to hunt with their mother. Females can produce one litter of young per year. Females reach sexual maturity at 2.5 months old (before they are weaned) while males reach sexual maturity at 14 months old.

Months and Times of Activity

They are mostly nocturnal creatures hunting at night but they are also known to hunt during the day. They are active all throughout the year. Short-tailed weasels are solitary animals, patrolling the borders of their territory and only coming together during breeding season.

Special Features, Stories, Relationships 

  • Many short-tailed weasels die of a parasitic nematode (Skrjabingylus nasicola) that infects the nasal passage, distorting sinuses until the pressure perforates the skull and causes death. It is believed that short-tailed weasels obtain this parasite from shrews.
  • This animal has been trapped by humans for its fur. It was commonly used to make robes for European royalty. It was seen as a sign of chastity and virtue because it was believed that the ermine would rather die than soil its white coat.
  • It is a common misconception that short-tailed weasels suck blood from their prey like vampires but they actually lap the blood from the wounds of their prey.
  • Several legends may be found at:
  • Children’s book featuring this animal: Ermine’s New Home by Stephanie Smith


Loso, H. 1999. "Mustela erminea" (On-line), Animal Diversity Web. Accessed November 04, 2014 at
"Montana Field Guide Short-tailed Weasel- Mustela erminea." Montana's Official State Website. Montana Natural Heritage Program & Montana Fish, Wildlife and Parks, 2010. Web. 12 Feb. 2013.
"Short-tailed Weasel." Ohio Department of Natural Resources, n.d. Web. 12 Feb. 2013.