I have spent many pleasant hours muskrat watching. Time spent in the company of these industrious little rodents is so rewarding, especially at this time of year when they are highly active and often use ice edges for feeding and grooming.
Muskrats are large, semi-aquatic mice and get their name from specialized musk glands. One of the most widely distributed mammals in North America, they can occupy any wetland that is shallow enough to permit the growth of their aquatic food (such as cattails, bullrushes) but is deep enough so that it does not freeze to the bottom during the winter.
Muskrats use their dexterous and hand-like front feet to dig out roots, burrow and hold their food. Their huge hind feet are not webbed, but have four long toes, each fringed with specialized hairs that act as paddles. Their tails are thin and flattened vertically.
Muskrats have two types of homes – lodges and bank burrows. Bank burrows are excavated while lodges are built by heaping mud and plant material into a mound, into which a chamber and one or two exit burrows are excavated. After freeze-up, they will also create feeding and resting stations (called push-ups) by chewing holes through the ice and topping these holes with vegetation and mud.
Muskrats are able to swim for long distances, thanks to the buoyancy provided by their luxurious waterproof fur. They are also efficient divers, able to hold their breath underwater for up to 15 minutes.
During the winter, they can travel considerable distances under the ice, locating their food and then returning with it to a push-up – all in total darkness!
Muskrats are promiscuous, with males competing fiercely for females. These battles are easy to observe at this time of year, as many of our wetlands are either melted out or ringed by open water. Although I have not yet been able to capture any good photos of these altercations, I can confirm that they are vicious.
Female muskrats can have up to three litters per season, with five to 10 young per litter. The kits, born blind, naked and helpless, develop rapidly: within a week they are furred; by two weeks they explore on their own; at three weeks they are weaned; and by six weeks they are independent. Their lives are harsh and short; few muskrats live to be older than three years of age.
Muskrat populations fluctuate, with by a dramatic decrease occurring every few years. It appears that a population crash occurred three to four years ago, as very few muskrats were seen in local ponds. Last summer their numbers started rebounding, and I am heartened this spring to see that many area potholes and small wetlands are once again busy with muskrat activity.
I highly recommend a spring visit to nearby wetlands for some quality muskrat watching.
Myrna Pearman is a retired biologist and passionate wildlife observer, photographer and writer. She can be reached at firstname.lastname@example.org.