Pygmy Right Whale: Neobalaenidae

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PYGMY RIGHT WHALE: Neobalaenidae

PHYSICAL CHARACTERISTICS

The pygmy right whale is the smallest of the baleen (buh-LEEN or BAY-leen) whales. It ranges from 5.2 to 7.2 feet (1.6-2.2 meters) in length and weighs around 4.5 tons (4,000 kilograms). Females are larger than males. The largest female ever recorded was 21.3 feet (6.45 meters), while the largest male was 20 feet (6.05 meters). The pygmy right whale is the only species in this family and should not be confused with right whales in the family Balaenidae.

Like all baleen whales, the pygmy right whale is a filter feeder. Pygmy right whales do not have teeth. Instead, it has many overlapping plates, called baleen plates, which hang like a curtain from the upper jaw. These plates are made of a material called keratin (KARE-ah-tin). This horny, fingernail-like material frays out into thin hairs at the end of each strand to make a strainer. The whale opens its mouth to feed and sucks in a lot of water. It then pushes the water out through the baleen plates and uses its tongue to lick up food that remains.

The pygmy right whale's head is one-fourth the size of its body. Its most noticeable characteristics are a highly arched jaw and large lips. Inside the pygmy's mouth are 460 ivory-colored baleen; these are lined up, with 230 on each side of the upper jaw. This baleen is thought to be more flexible and tougher than the baleen of any other species. Each piece varies from 1 to 28 inches (2.5 to 70 centimeters) wide and can be as long as 4 inches (10 centimeters). The size of each baleen depends on where it is in the mouth.

The head of the pygmy right whale has more hair than most other whales, with 100 hairs on the upper jaw and over 300 on the tip of the lower jaw. This whale has very small eyes, but good sight is not very important to it in finding food.

The pygmy right whale has a dark gray head that, with age, gets lighter along the lower jaw until it turns white on its underside. The back of the whale is also dark gray and has two blowholes located near the front of the head. Two-thirds of the way back is a very small dorsal (back) fin. The fin grows to be only about 6 inches (15 centimeters) high. The flippers are darker than the rest of the body. They are very narrow and are rounded at the ends.

GEOGRAPHIC RANGE

The pygmy right whale lives deep in Southern Hemisphere in the Atlantic, Pacific, and Indian Oceans. Most often this species is seen around Australia, Tasmania, New Zealand, South Africa, and the southern tip of South America.

HABITAT

Pygmy right whales live where the surface water is between 41 and 68°F (5 and 20°C). Not much else is known about the habitat preferences of this whale.

DIET

The pygmy right whale eats small squid, octopus, krill, and shrimp-like marine animals. Their method of feeding has never been observed, but it is thought that this whale uses a surface-skimming technique instead of diving deep to feed.

THE RAREST WHALE

The pygmy right whale is the rarest and least understood of all the baleen (filter feeding) whales. Only about two dozen specimens have been studied. Some things about this whale resemble whales in the rorqual family. Other characteristics are similar to whales in the right whale family. In the past, pygmy right whales have been classified as part of the right whale family, but today, scientists believe that it is different enough to be put in a family of its own.

BEHAVIOR AND REPRODUCTION

There have been very few sightings of pygmy rights, so little is known about their behavior. They are often seen in pairs or pods of up to ten individuals, but there have been occasional sightings of groups as large as eighty. To communicate, pygmy right whales use intense thumps or tones, each quickly rising and slowly falling, as the frequency drops.

The pygmy right whale is a very slow swimmer. It often spends only a few seconds on the surface when it comes up for air, usually just sticking its snout out of the water. The longest recorded dive of a pygmy lasted only four minutes. This whale is not known to do any acrobatic leaps out of the water. It is rarely seen at sea.

Since so little is known about the pygmy whale, there is little information about the mating season, mating practices, or length of pregnancy. Calves are around 6.5 feet (2 meters) at birth. Many researchers believe that calving may take place year-round. Calves stop nursing when they are between 9 and 11.2 feet (3 and 3.5 meters) long. Sexual maturity (the ability to reproduce) is reached when the animals are about 16 to 20 feet (5 to 6 meters) in length. Their average lifespan has not been determined.

PYGMY RIGHT WHALE AND PEOPLE

The pygmy whale has little to no contact with humans. Because it is so rare, the pygmy has never been hunted. The only human-caused deaths come from occasional entanglement in fishing nets.

CONSERVATION STATUS

Only a few dozen pygmy right whales have ever been examined, and only a few hundred have been identified. They are not on the endangered species list because of a lack of information, but are still thought to be threatened with extinction.

They are the only baleen whales not to have been threatened by large-scale commercial hunting. There is concern that this whale might be confused with the Antarctic minke whale, which it resembles. The Antarctic minke whale is still hunted by Japanese whalers. The pygmy is thought to be threatened by global climate change, but not by toxic pollution. Overall, it seems to be so rare not because of the lack of animals, but because of a lack of data and research.