Otters are mustelids, a feisty group of mammals that includes weasels, ferrets and wolverines. They are sizeable mammals that range in weight from 15 -30 pounds and in length from 4-5′ long (including the tail). Males are usually much bigger than females. Their streamlined bodies and powerful limbs make them spectacular swimmers and agile hunters. They feed primarily on fish but also enjoy crayfish, crabs, frogs and snakes. They live in family groups of 5-12, hunting, playing and denning together. Otter families have sizable home ranges that encompass several square miles. They often live more than 10 years in the wild and even longer in captivity.

These mammals spend much of their time in the salt marsh where crabs, mullet and other fish species are easily captured. Freshwater pond activity occurs mostly in the winter months when there is less food in the salt marsh.

Otters add to the value of the nature experience on Spring Island and other areas where they are found. Although otters sometimes feed on stocked fish and frolic in water features and water gardens, they are remarkable animals.

Otters, eagles, herons, cormorants and mink feed on fish in our freshwater ponds. This predation by native species is a natural part of living within a nature preserve. Underwater structures provide places for fish to hide, thereby reducing the success of otters and other predators that are hunting them. Hundreds of structures have been added to the Goose Ponds, Tabby Links Ponds and Ruins Pond to protect the fishery.