Predators and Competitors of the Marine Otter

The information below comes from Cabello in IUCN: Otters (1977) and Larivière (1998).


The main predator is the Killer Whale, Orcinus orca, which comes right in to the coast. Sharks of various species also take the animals. Reed-Smith (Gonzalo Medina, pers. comm.) says juveniles may also be taken by birds of prey.


Gulls (Larus dominicas) have been seen stealing food from otters. Sothern Sea Lions (Otaria flavescens) compete for fish, especially the larger fish. Various other cetaceans (Delphinus and Lagenorhynchus sp) also take the same prey. The Cormorant, (Phalocrocorax olivaceous), Magellanic Penguins (Speniscus magellanicus) and other fish-eating birds are also competitors.

The Southern River Otter, Lontra provocax, eats about 90% of the same food items, but mainly hunts in calm bays and inlets rather than the exposed rocky shores preferred by the Marine Otter.


These otters often carry a heavy burden of nematodes and acanthocephalans, whose vectors are crustaceans. Helminths have also been found.

Marine Otter