BROWN LEMMING Latin Name: Lemmus sibiricus Habitat: All of Alaska, except for Southcentral and
Southeast Alaska, and the Kodiak island group Classification: Mammal, herbivore
COLLARED LEMMING Latin Name:Dicrostonyx groenlandicas Habitat: Northern Alaska, Unalaska Island, Umnak Island, Saint Lawrence Island, Canada, Greenland, Europe, and Asia Classification: Mammal, herbivore
NORTHERN BOG LEMMING Latin Name:Synaptomys borealis Habitat: Most of Alaska, western Canada, and northern Washington Classification: Mammal, herbivore
BROWN LEMMING
These small rodents are the most common and the only true lemmings in Alaska. They have reddish-brown fur that sometimes, but not always, turns gray in the summer months. Their long fur almost completely hides their small ears and short tail. Their dark, beady eyes can be clearly seen in their fur above their triangle-shaped snouts. Brown lemmings have sharp nails on tiny, furry feet. Their front feet are strong, and the nails give them traction on slippery surfaces and the ability to dig and root for homes and food. When full-grown, brown lemmings are usually about six inches long and weigh between two and four ounces.
Think about it:How do lemmings use their toenails?
Dirt Roads
Lemmings do not hibernate, even when winter is at its coldest. They burrow their holes in low areas in the snow and track small pathways to and from nests. When food becomes scarce during the winter, the brown lemming has to dig through ice and snow to retrieve grasses, seeds, bark, sedges, and bulbs for meals. Their incisors, or front teeth, never stop growing and are strong enough to chew through tough plants. Though brown lemmings are primarily plant-eaters, they may also eat insects and have been suspected of killing and eating each other at times when food is particularly scarce.
Think about it: Are lemmings picky eaters?
Base Jumpers?
Times of starvation may be the cause of the biggest myth about lemmings. The lemming population is directly dependent on how many predators and food sources they have.
Populations of brown lemmings can consume too much food. Instead of staying home and starving, lemmings often migrate in large numbers to new areas they would never travel to otherwise. They can enter towns or swim rivers and lakes, sometimes drowning, as they search for food. Numbers of brown lemmings may even get trapped on lake and sea ice, making them vulnerable to many predators, such as owls, hawks, wolves, and foxes. Because of this massive migration, many people still believe in the old European myth that lemmings will follow each other off of cliffs to their death.
Think about it: What really causes lemming numbers to decrease?
COLLARED LEMMING
Don't be fooled. In spite of their name, collared lemmings are actually part of the vole family and are not true lemmings. These small rodents are well-adapted to the northern arctic regions of Alaska. They have soft gray fur and a black line that traces their backs from their head to their short tails. Their small ears are barely visible, but are the same color as a light brown circle of fur around their necks. Collared lemmings usually grow to about seven inches long and weigh about two ounces.
Think about it:Why is this animal called a "collared" lemming?
Sneaky Little Buggers
The collared lemming has unique characteristics that allow it to adapt in Alaska's winter. They are the only member of the vole family that changes color in the winter. Collared lemmings turn snowy white at the end of the fall. The third and fourth claws on their feet grow especially long in the winter, allowing collared lemmings to dig easily for food in the snow and ice. They shed these longer claws when they are not needed in the summer.
Think about it: Can you think of other Alaska critters that change colors with the seasons? How does that help them?
Underground Decorators
Collared lemmings dig burrows and nests that are usually two to three feet deep. They line the inside of their tunnels with grass and moss, and unlike the brown lemming, they are usually careful to keep from making tracks toward the entrances of their nests. Strangely enough, collared lemmings build a kind of "bathroom" additions to their underground burrows. They usually have an extra room that is separate and keeps the living and breeding space sanitary.
Think about it: Collared lemmings know instinctively to keep their living space clean by using a different place for their waste. Why would that be important?
Stay out of my room, please!
Like brown lemmings, collared lemmings eat a variety of grasses and plant life. But unlike their distant cousins, these lemmings are not nearly as likely to migrate. Though they have been known to move in numbers, they do so infrequently. Collared lemmings are generally more private and secluded. They can be angry rodents and have been known to bite humans.
Think about it: Just a reminder--never approach or try to touch a wild animal.
NORTHERN BOG LEMMING
Bog lemmings are the smallest of the three kinds of Alaskan lemmings. They are not true lemmings, but a species of rodent that is more closely related to voles. They are commonly called lemming mice. They rarely grow longer than four or five inches and weigh barely one ounce.
Think about it: If you can, use a scale to weigh something that's only one ounce.
Some Like it Soggy
Other than their smaller size, northern bog lemmings have a few differences from the other lemmings of Alaska. They live in the meadow and bog lands of Alaska, preferring warm and wet climates. Their brown and black fur is not very thick. They have white fur on their bellies and on the underside of their tails.
Think about it:The northern bog lemming is color-coordinated with its surroundings. What colors do you see in a bog?
What's that on your teeth?
True lemmings do not have grooved teeth. Because of this, the northern bog lemming cannot be classified as a true lemming. They have grooved front teeth. They feed on grasses, bulbs, herbs, and insects. Northern bog lemmings build homes that are similar to brown and collared lemmings, but use warmer climate plants like moss to line the tunnels.
Think about it: Which lemming makes its tunnels in snow? Compare its habits to those of the northern bog lemming. How are they each uniquely adapted to their surroundings?
