Understanding the Walrus
The walrus is a significant marine mammal known for its prominent tusks and considerable bulk, and it plays a vital role in the ecosystems of the Arctic region.
Species and Subspecies
The scientific name for the walrus is Odobenus rosmarus, which belongs to the pinniped family.
This family also includes seals and sea lions.
There are two recognized subspecies of walrus: the Atlantic walrus (Odobenus rosmarus rosmarus) and the Pacific walrus (Odobenus rosmarus divergens).
The primary differences between these two lie in their geographical distribution and slight variations in physical features.
Physical Characteristics
Walruses are characterized by their long tusks, which can reach lengths of up to one meter.
Both males and females possess tusks, which are actually elongated canine teeth.
Walruses use their tusks for various purposes, including hauling themselves onto ice and social interactions.
These mammals also have a layer of blubber under their skin, which provides insulation in the cold Arctic waters.
Male walruses are generally larger than females, with some males weighing over 2000 kilograms.
- Average weight for males: 800–1700 kg
- Average weight for females: 400–1250 kg
Walruses also have a thick hide covered by a sparse layer of fur, and they utilize their large flippers for swimming in the chilly Arctic seas.
Habitat and Distribution
The natural habitat of the walrus is in the frigid waters and ice floes found within the Arctic Circle.
While the Atlantic subspecies predominantly resides in areas surrounding Canada and Greenland, the Pacific subspecies has a broader range and can be found in waters off Russia and Alaska.
Their distribution is also influenced by the presence of sea ice, which they use for resting, giving birth, and protection from predators.
- Atlantic walrus distribution: Canada, Greenland
- Pacific walrus distribution: Russia, Alaska
Walruses spend a significant amount of time in the water, but they are also known to congregate in large groups on land or ice when it is available.
They can be frequently observed lying on the ice with hundreds of companions, highlighting their social nature.
The Life of a Walrus
The majestic walruses are a prime example of marine adaptation, with their distinctive tusks and social habits, residing primarily in the Arctic’s chilly waters.
Their life cycle, from what they eat to how they mate and protect themselves, embodies the intricate balance of marine ecosystems.
Diet and Feeding Habits
Walruses are primarily benthic feeders, with a diet consisting heavily of benthic bivalve molluscs, such as clams.
They use their sensitive whiskers to detect their prey in the dark waters.
Despite their large size, walruses are not typically aggressive hunters.
They consume a wide range of other food items including shrimp, crabs, tube worms, soft corals and tunicates.
An adult walrus is estimated to eat about 3,000 to 6,000 clams in a single feeding session.
Social Behavior and Reproduction
Walruses are known for their social nature, often found in large herds on ice floes.
They communicate through vocal and physical displays.
During the mating season, male walruses will assert dominance to attract females through vocal displays and bouts of physical altercation.
Females give birth to a single calf after a 15 to 16-month gestation period.
The young are then nurtured in the herd, learning to swim and hunt with the protection of their mothers and the larger group.
Threats and Conservation Efforts
Climate change poses a significant threat to walrus populations, as melting ice reduces their habitat.
The loss of ice floes forces herds onto land, leading to overcrowding, which can result in crushing incidents among calves.
They also face challenges from predators like the polar bear and increasing human activities in the Arctic.
Organizations like the WWF have classified walruses as “vulnerable,” emphasizing the need for international cooperation to monitor and implement conservation efforts to prevent their extinction.
Comprehensive strategies include protecting critical habitats and managing human-walrus encounters to ensure the sustainability of these important marine mammals.