A large male’s tracks may resemble a small female Long-Tailed Weasel’s track.
Track Length: 0.8 – 1.3 inches (2.0 – 3.3 cm)
Track Width: 0.5 – 0.6 inches (1.3 – 1.5 cm)
Straddle: 1.0 – 2.1 inches (2.5 – 5.3 cm)
Stride: 9 – 35 inches (23 – 89 cm)
Length with tail: 20 – 36 cm
Head and Body: Male = 15 – 24 cm, Female = 13 – 21cm
Tail length: Male = 6 – 9 cm, Female = 5 – 7cm
Weight: Male = 70 – 172 g, Female = 47 – 73 g
Short-Tailed Weasel (Ermine)
Mustela means “one who carries off mice”.
Short-Tailed weasels may be the most abundant land carnivore in Ontario.
Europeans gave the Short-Tailed weasel two different names; stoat and ermine. A weasel with a dark summer coat is called a stoat and a weasel with a white winter coat is called an ermine. However, it is best to avoid the stoat and ermine labels since all three weasel species in Ontario alternate between brown coats in summer and white coats in winter. The short-tailed weasel is active during the day during the summer months. In the winter, the short-tailed weasel is more active at night. Short-Tailed Weasels have bright blue green eyeshine. These weasels can be attracted to squeaking calls imitating a young bird.
The tail of a Short-Tailed Weasel measures less than half of their head and body length whereas the tail of a Long-Tailed Weasel measures more than half of their head and body length. Short-Tailed weasels have lemon yellow highlights on their belly and they have white feet. Short-tailed weasel fur turns white in winter and just the tip (0.5 inches at most) of their tail is black. White hairs are hollow and they provide better insulation than hairs that have pigment. This cold weather adaptation helps trap air that is warmed by the body similar to the way a down vest works to keep a human warm.
Short-tailed weasels breed between June and August. They exhibit delayed implantation and bear 4-8 young in April or May of the next year.
The home range of a male short-tailed weasel is 37 acres (15 ha) and the home range of a female short-tailed weasel averages 10-25 acres (4-10 ha). Short-tailed weasels make circuits of their home range every 10-15 days.
Short-Tailed weasels are small mammal specialists. In cold weather, short-tailed weasels hunt mostly under the snow (especially the females) where mice and voles are active all winter. They prefer the subnivean space where there is a melted-out gap between the snow and the earth. This gap provides a space for movement and insulation. They also eat jumping mice that are hibernating under the snow.
Short-Tailed Weasel Scat
Short-tailed weasel scat is 0.3 cm – 0.8 cm wide and 1.9 cm – 6 cm long. Short-tailed weasels are carnivorous. Mark Elbroch (in Mammal Tracks and Sign) writes that they are more carnivorous than larger weasel species.
In snow, the Short-Tailed Weasel’s shorter strides may be connected by drag marks (dumbbells) and often alternate with longer strides throughout the length of the trail. Its bounding track may show short strides alternating with long ones.
The stride length in the above photo is 36 cm.
Please visit my “All about Weasels” page for more information: https://natureguelphtracking.wordpress.com/mammals/weasels-otters-and-relatives/all-about-weasels/
Alexis Burnett, Earth Tracks Apprenticeship Program
Rezendes, P. 1999, Tracking and the Art of Seeing, HarperCollins Publishers, New York.
Elbroch, M. & Rinehart K. 2011, Behavior of North American Mammals, Houghton Mifflin Harcourt Publishing Company, NY.
Reid, F. A., 2006, Mammals of North America, Houghton Mifflin Company, NY.
Eder, T., 2002, Mammals of Ontario, Lone Pine Publishing, Edmonton, AB.
Sheldon, I. Animal Tracks of Ontario, Lone Pine Publishing, Edmonton, AB.