Thinking mink

We still are learning new things about Thornwood Nature Preserve all the time, and now we have another discovery.

An animal we didn’t know about was discovered at Thornwood. Thanks to Adam Wilson (he was out there for bird pictures, but they seemed to be hiding that evening). Adam sent me a picture, and we have found out we have minks at the preserve.

Indiana minks are found in every county in the state, most being up in the northeast, where there are more bodies of water.

Minks usually are dark brown top and bottom with a white spot on the chin. The mink is sometimes confused with the weasel, but its tail is bushier and it is larger. The tail comprises about one-third of the total length. Males run about two pounds and 24 to 27 inches, while the females run one-and-a-half pounds and 17 to 21 inches long.

Minks generally hang out at the borders of lakes, marshes and ponds but can also be found along rivers and small streams. They generally take over a muskrat hole, and in the process, eat the muskrats. Most of the time, their food is water types, fish, frogs, crayfish and such; however they have been known to eat rabbits, voles, poultry and snails. One was found to have a 12-inch garter snake in its stomach.

Their breeding season is in March, with the young being born in late April or early May. The young are born helpless and about one-quarter of an ounce in weight. At one month old, they are eating solid food; within a couple of months they are out hunting with their mother, and during the autumn, they leave the den and go out on their own.

Minks can dive as deep as 15 feet in the water and swim underwater for 100 yards. They are mostly nocturnal but at times can be seen in daylight (hence the picture). Mink dens are found mostly at the water’s edge, the burrows are three to four inches in diameter and 10 to 12 feet long. They may also have dens in hollow trees or logs and even tile drains. The nest they make in these dens is about one foot in diameter and is lined with dry grass, leaves and the fur and feathers (yes, they will catch birds) of their victims.

The males are solitary creatures and will sometimes leave their den and travel in their hunting circuit, which may be several miles and take a week or more to complete, staying in a different den every day. So, on the down side our mink may have just been passing through. They don’t hang around to raise the babies.

Be careful if you approach one; when disturbed or excited they may have a discharge from the anal glands. This discharge is said to stink worse than the skunks does, and we all know how bad that is.

Minks are still trapped for their fur, however, I looked up the going price of last year’s sale and they were running from $1.00 to $8.50 for a good hide. Hardly seems worth it.

What is the biggest danger to the population of minks? Not too surprising: It’s humans, not by trapping, but by draining the wetlands where minks live.

Joe Whitfield is a naturalist and gardener for the Greenfield Parks and Recreation Department. Send comments to