The North American river otter (Lontra canadensis) once thought to be eradicated on Long Island is making a return. Historically, the river otter was found in a range of various aquatic environments on Long Island, including saltwater, fresh, and brackish water. While their name alludes to them being specialized to rivers, they aren’t particularly picky when it comes to habitat. Sharing the same family as a weasel, the river otter can be identified by their streamlined and stout body type. Glossy fur, a strong muscular tail, and webbed feet are some of the more easily observable characteristics. While spending most of their time in water, their diet primarily consists of fish and aquatic species. However, their diet ranges and can include small mammals like muskrats, and even birds or fruit.
Nearly two hundred years ago, river otters were a fairly common sighting. However, a combination of habitat loss, unregulated trapping, and pollution were the key causes of the river otter’s decline on Long Island. Despite being nearly extirpated from the area, with help from conservation groups their populations are slowly increasing on Long Island. Conservation efforts including laws established in the 1930s and a ban on trapping were key factors in their repopulation.
One of these groups, the Seatuck Environmental Association, is actively surveying the otter population here on Long Island. Home ranges of the river otter are identified by their latrine sites. River otters tend to choose one spot as a designated area to deposit their waste, typically on a small piece of land or object that protrudes from water. Long Island wildlife biologist Mike Bottini has led one of these studies, where in 2008 there were 22 latrine sites found across 143 areas. Compared to 2018, that number has grown to an even greater number of 168 areas with 77 latrine sites. Presences of river otters have also been documented by unfortunate vehicle strikes, which could indicate that a source of water for them to survive in was nearby. The otters that are returning still face some challenges, despite being at the top of the food chain. Pollution is still a factor, and being at the peak of the chain means they have a greater chance of being exposed to environmental contaminants. The roads and structures on Long Island also present their own unique challenges, as they can impede on an otter’s movement through an area.
The conservation efforts provided to these otters were very effective. Through valiant efforts of dedicated members of our communities along with scientists, it goes to show how powerful the effect of the work being done is. Conservation efforts and laws helped a population once thought to be nearly extinct from our home.
If you see an otter, it can be reported to the Seatuck Environmental Association through their online community science project at seatuck.org.
By Dan DeFeo