Although surprisingly nimble on land, the marine otter is adapted for life in the water and can be seen swimming with the head and upper back out of the water and the body submerged. It makes frequent 15 to 30 second dives to a depth of 40 metres whilst searching for fish, cephalopods, crustaceans and molluscs. It has also been recorded eating shore-side fruit when in season. It emerges from the sea to eat, rest and play on rocky islets and it will also scent mark with pungent urine to claim these rocks as its own. Marine otters will fight over food and favoured rocks, squealing loudly and biting each other’s faces. Despite this, otters are not strongly territorial, and the ranges of many males and females overlap. They have even been seen to fish cooperatively (2).
The reproductive behaviour of the marine otter is poorly understood, but they are thought to be monogamous unless both prey and potential mates are abundant, when they mate with many partners. Mating occurs in December and January and cubs are born from January to March in dens or concealed areas amongst rocks and vegetation. Between two and five cubs are born and these remain with their parents for around 10 months as they are fed and taught to hunt for themselves (2).