Reading: Chủ đề Narwhal

The Narwhal is a medium-size whale that lives in the Arctic region year-round. It is characterized by its single, straight tusk, which is actually an elongated canine (tooth) that grows to a length of ten feet. Normally, such tusks are unique to males. Occasionally, a male narwhal will have two tusks. The tusk functions as a sensory organ and is rarely, if ever, used for aggressive or defensive purposes. The Narwhal itself can grow to about 18 feet in length, but most average about 13 feet. Narwhals can weigh up to 3,500 pounds.

The word “Narwhal” comes from an old Norse (from Norway) word meaning “corpse.” The Narwhal’s greyish, drab coloration reminded sailors of a dead body.

The Narwhal feeds about Arctic fish such as cod and halibut, as well as shrimp and squid. Because Narwhals lack teeth, it is thought that they swim towards their prey and suck it into their mouths.

Narwhals are a migratory species of whale. They migrate to shallow, ice-free, coastal waters in the spring in pods (groups) of 10-100 individuals. In winter, they move to deeper waters under pack ice. Narwhals can dive to depths of over 2,500 feet and can stay under water for 25 minutes or more. Their dives are among the deepest ever recorded for marine mammals. They use sonar to guide themselves through the murky depths.

Scientists believe there are about 75,000 Narwhals living in the Arctic waters. Individuals in the wild can live up to 50 years. Narwhals are thought to be extremely sensitive to climate change and reduced pack ice in Arctic waters.

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