Lutra lutra individuals eat fish, crustaceans, clams, small mammals and amphibians, birds, eggs, insects, worms, and a small amount of vegetation. They use their vibrissae (whiskers) as sensing organs underwater to monitor the movements of fishes and other prey. River otters hunt and feed several times a day, consuming about 1kg of food daily. (Grzimek 1990, MacDonald 1984, Heggberget 1994)