The Walrus – Odobenus rosmarus is a large, flippered marine mammal found in the Arctic and subarctic regions of the Northern Hemisphere. These impressive creatures are easily recognizable by their massive size, tusks, and whiskered snouts. They are highly adapted to their cold, icy environment and play a vital role in the Arctic ecosystem.
Description & Characteristics
The Odobenus rosmarus is one of the largest pinnipeds, with males reaching up to 4 meters in length and weighing over 1,500 kilograms. Females are typically smaller, averaging around 2.7 meters in length and 700 kilograms in weight. Their bodies are robust and streamlined, with thick blubber layers for insulation against the frigid waters. Their short, powerful flippers allow for efficient swimming and maneuvering through ice and water. The Odobenus rosmarus is characterized by its prominent tusks, which are elongated upper canine teeth that grow continuously throughout their lives. These tusks are used for a variety of purposes, including digging for food, fighting, and hauling themselves onto ice floes.
Habitat and Occurrence
The Walrus – Odobenus rosmarus primarily inhabits the Arctic and subarctic regions of the Northern Hemisphere. They are found in the icy waters of the Arctic Ocean, including the Bering Sea, Chukchi Sea, and the coastal waters of Alaska, Canada, Russia, Greenland, and Norway. They spend much of their time on sea ice, using their tusks to haul themselves onto the ice and create breathing holes. As the sea ice melts during the summer months, the Odobenus rosmarus migrate towards land, often congregating in large herds on beaches and rocky islands. They are commonly found in the following marine zones: the neritic zone (coastal waters), the benthic zone (seafloor), and the pelagic zone (open ocean), where they forage for their food.
Taxonomy
The species Odobenus rosmarus belongs to the Class: Mammalia, Order: Carnivora, and Family: Odobenidae. They are the only living member of the Odobenidae family, which is closely related to seals and sea lions. There are three recognized subspecies of Odobenus rosmarus: the Atlantic walrus (Odobenus rosmarus rosmarus), the Pacific walrus (Odobenus rosmarus divergens), and the Laptev Sea walrus (Odobenus rosmarus laptevi). These subspecies are distinguished by their geographic distribution, body size, and tusk morphology.
Feeding
The Odobenus rosmarus is an opportunistic feeder and consumes a wide variety of prey, including: clams, crabs, crustaceans, edible crab, fish (little fishes), invertebrates, schrimps, snails, worms, zoobenthos, and carrion. They use their powerful tusks to dig up clams and other bivalves from the seafloor. They also use their sensitive whiskers to detect prey buried in the sediment. Their diet can vary seasonally and geographically depending on the availability of prey.
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