What's That Creature in the Water? part 1

North American river otter swimming -Wikimedia

No, it is not the Creature from the Black Lagoon or the Loch Ness Monster but there are some odd aquatic and semi-aquatic mammals that you might spot in the fresh waters of New Jersey.

Mink and beaver are native New Jersey mammals found in and around freshwater that most citizens of the state rarely ever see. Other aquatic and semi-aquatic mammals – including otters, weasels, ermine, fishers, and muskrats – are also here but elusive. They are most active at dawn, dusk, and nighttime when people are less active.

“They are incredibly secretive,” said Dr. Emile DeVito, staff biologist for the New Jersey Conservation Foundation. “Nobody really studies them in New Jersey. They are an overlooked group of animals, except by trappers.”

They are not really endangered or threatened in NJ even though they seem rare. It is thought that these aquatic mammals are actually becoming more common. Why? The reasons are actually good news: cleaner waters, more forest cover, and less trapping. 

Here are three of these elusive mammals. Maybe if you're out today for a Thanksgiving walk in the woods to build up your appetite or burn off the big dinner, you might be lucky enough to spot one. (In part 2, I will cover four others.)

American mink - Wikimedia

Mink (Mustela vison) are known for their exceptionally beautiful and soft fur. The American mink is lanky with a long tail, short legs, and partially webbed toes, which make them excellent swimmers. They are solitary creatures and quite territorial. They like to feed on crayfish, frogs, fish, mice, reptiles, earthworms, and even waterfowl. Take note that like their skunk cousins, mink defend themselves by spraying a foul-smelling liquid.

American beaver

Beavers (Castor candensis) are like humans in that they reshape their environment to suit their needs. That's rare in any animals. They will damn a stream to create a pond, and then build a separate beaver lodge by piling up mud, rocks and sticks inside the lodge to form a “floor” above the water.

Unlike mink, beavers are communal and live in groups. They also differ from most of these other mammals in that they are not carnivorous. They stand apart from their fellow members of the rodent family as vegetarians whose favorite foods include water lily tubers, spatterdock, clover, algae, apples and the leaves and green bark from trees.

North American river otter - Wikimedia

If you have ever spotted some river otters (Lutra canadensis) you would know that they're the most aquatic members of the mustelid family and often appear quite playful - as when they are sliding down riverbanks into the water. 

They have long stiff whiskers that help them find prey. They have flaps that allow them to close off their nostrils and ears to remain underwater for up to eight minutes on one breath. They are very social and form family groups centered on a female and her young. They eat fish, reptiles, amphibians, crustaceans, mollusks, insects, and even small birds and mammals.