Animal Encyclopedia Category: Marine Mammals

Coastal populations of common bottlenose dolphins are more territorial and utilize a larger number of coastal habitats – from bays and estuaries to seagrass beds, beaches, and other ecosystems. Oceanic populations are more migratory in nature and apparently do not visit coastal ecosystems. Common bottlenose dolphins can be quite large, reaching weights of up to 1400 pounds … Read more

Sperm whales have several specialized physical characteristics that aid in this predatory behavior. They have large conical teeth for ensnaring their preferred prey. Like most active predators, they have large brains and in fact, the sperm whale has the largest brain of any animal on the planet. They also have the most powerful sonar of any animal, which … Read more

The walrus’s tusks are actually greatly elongated canine teeth. Both males and females have tusks, with the males’ being much longer. The largest tusks can reach lengths over three feet (one meter) long. They are used to fight to establish dominance hierarchies, to avoid predation, and to haul out on the ice surface to rest. They may also be … Read more

Steller sea lions are generalist predators that eat a variety of large, marine fishes (Pacific Cod, Pollack, salmons, flatfishes, etc.), along with squids and octopuses. They are known to pester fishers by eating fishes out of their nets, bringing them into dangerous contact with humans. As they are some of the largest animals throughout their range, steller … Read more

This species feeds on schooling, mesopelagic fishes and squids in the open ocean. Like their prey, spinner dolphins form large groups – typically composed of hundreds or even thousands of individuals – for hunting and socializing. Spinner dolphins are known for being quite playful and put on impressive aerial displays, breaching and spinning regularly. Mating also occurs in groups, … Read more

The charismatic sea otter is one of the most well-known marine mammals today. The largest member of the weasel family, they can grow to be nearly 5 feet long and weigh almost 100 pounds. They spend nearly their entire life in the ocean in the temperate coastal waters on the Pacific Coast and have a … Read more

Marine otters are foraging predators that eat a wide variety of prey. While they prefer invertebrates, including crabs, clams, and other hard-shelled groups, they are also known to eat some fishes, juvenile birds, and even other mammals. They also scavenge for garbage, bringing them into close contact with people. Unlike many species of weasels, scientists believe the … Read more

Though they are quite large (up to 46 feet/14 m), gray whales feed on small benthic worms and other invertebrates. Through a unique feeding strategy known as suction feeding, gray whales bite off huge mouthfuls of soft sediments (sand or mud) from the seafloor and then constrict the muscles of their mouths and throats to force out … Read more

Interestingly, though they are enormous, fin whales are not predatory. They filter feed for tiny krill or small pelagic fishes and are totally harmless to people (other than through accidental collisions). This life history strategy is common among several large animals in the ocean, including the whale shark, the basking shark, and the other great whales. Like all … Read more

Belugas, however, are typically more solidly white than their grayish cousins. Adult belugas are also slightly larger than narwhals, reaching lengths of around 18 feet (5.5 m). Interestingly, the beluga whale is the only species of cetacean (whales and dolphins) that has a movable neck. Belugas can move their heads up and down and from side to side. … Read more