Right Whales and Bowhead Whales: Balaenidae

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RIGHT WHALES AND BOWHEAD WHALES: Balaenidae

BOWHEAD WHALES (Balaena mysticetus): SPECIES ACCOUNTS
NORTH ATLANTIC RIGHT WHALE (Eubalaena glacialis): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Right whales and bowhead whales are baleen (buh-LEEN or BAY-leen) whales. Like all baleen whales, these whales are filter feeders. Right whales and bowhead whales do not have teeth. Instead, they have many overlapping plates, called baleen plates that 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, caught by the plates.

Right whales and bowhead whales are generally between 43 and 65 feet (13 to 20 meters) long. They weigh between 168,000 and 224,000 pounds (76,200 to 101,600 kilograms). They have large heads and a curved mouth that allows them more baleen surface than baleen whales with a straight mouth. Because they are mammals, whales must come to the surface of the water to breathe. They breathe through a blowhole located on top of their head. The blowhole is connected to the lungs.

Bowhead and right whales are almost entirely black, but they do have a patch of white around their chin, as well as a band of lighter color on their tail. The easiest way to tell the difference between a bowhead whale and a right whale is that right whales have bumps around their head, near their mouth, and around their eyes. These bumps are actually places where small animals known as whale lice live. These parasites are not thought to be harmful to the whales. Bowhead whales do not have these bumps.

GEOGRAPHIC RANGE

Right and bowhead whales can be found throughout most of the world's oceans and seas. They go farther into the Arctic than many other whales and are capable of breaking through newly formed ice up to 9 inches (23 centimeters) thick. These whales do not generally enter the warmest waters close to the equator.

HABITAT

Right whales and bowhead whales travel long distances and can live in a variety of habitats. They generally find warmer temperatures for birthing along coastal regions and bays. They are capable of traveling far into the polar regions and navigating through icy waters to find krill for feeding.

DIET

Right whales and bowhead whales feed on small marine animals called krill by using their baleen. They do this by taking in water and krill as they open their large mouth. Next, they close their mouth most of the way, until only the baleen is exposed between their lips at the sides of the mouth, like a sieve (SIV). Then they push the water through the baleen and out between their lips, but the krill are trapped in the baleen and are left in the whale's mouth. By scraping the baleen with their huge tongue, the whales are able to swallow the food that is left after the water rushes out.

WHALES AND MYTHS

Whales have played an important role in popular culture. In the story of Pinocchio, a father and his wooden boy are swallowed by a whale. In Moby Dick, Captain Ahab pursues a white whale that attacks his ship. While these tales tell us of the fear that people have had of whales for centuries, it is important to remember that whales do not feed on people. Most large whales are not even capable of swallowing a person.

BEHAVIOR AND REPRODUCTION

Like all baleen whales, bowhead whales and right whales migrate. They spend the colder times of the year in warmer water closer to the equator and then move towards the polar regions of the Arctic and Antarctica where they spend the rest of the year. They do most of their feeding in the colder regions, and give birth in the warmer areas. Female right whales and bowhead whales give birth to one young at a time after a year of pregnancy. The young are nursed for about six months. They reach maturity after eight or nine years. Right whales can live as long as seventy years, but bowheads can live even longer, some past one hundred years.

Right and bowhead whales are known for their songs and the other types of sounds they make. Some people have described these sounds as grunts, roars, growls, belches, complex screams, or pulses. In the springtime, bowhead whales send out complicated songs with themes, sets of notes that are repeated. It is thought that these serve as communication between males and females.

RIGHT WHALES AND BOWHEAD WHALES AND PEOPLE

Throughout the nineteenth century and until recent times, right and bowhead whales were among those whales most sought by hunters. Whalers would bring in thousands of whales every year. Not only were whales a plentiful source of meat, but their blubber could be used to make oil for lamps. The baleen whales were particularly prized, because baleen could be used to make hoop skirts, shirt collars, and other clothing items because it was stiff, yet flexible. The invention of electric lighting, as well as new kinds of metal and plastic, has eliminated the need for almost all whale products in the modern world. In the 1930s, the International Whaling Commission banned the hunting of right and bowhead whales, although some hunting still occurs illegally. Native people of the Arctic are still allowed to hunt whales, and they use them for food, oil, and in the construction materials of sleds, baskets, traps and other items.

ANCIENT TREASURES

In 1995, a bowhead whale was killed in Alaska. When it was processed, it was found to have two stone harpoon blades in its flesh. This type of harpoon has not been used to hunt whales since the late 1800s. This means that the whale had to be over one hundred years old when it was killed.

CONSERVATION STATUS

Bowhead whales and southern right whales are considered at low risk for extinction, dying out. However northern Pacific right whales and northern Atlantic right whales are considered Endangered, facing a very high risk of extinction in the wild, and it is thought that fewer than 250 mature individuals remain. Since commercial whaling began, the population of these two endangered species has been reduced by 95 percent. It is questionable whether they will ever recover.

BOWHEAD WHALES (Balaena mysticetus): SPECIES ACCOUNTS

Physical characteristics: Bowhead whales grow to a length of 46 to 65 feet (14 to 20 meters) and can weigh as much as 112 tons (102 metric tons). They have the longest of all whale jaws and can have as many as 350 baleen plates in their mouth. They have no dorsal, or back, fin, but they do have a muscular bulge around the blowhole. They are almost entirely black except for a white patch at the front of their jaw. The bowhead has longer baleen than any other whale— its baleen can measure 25 feet (4.5 meters) long.

Geographic range: Bowhead whales are found mostly in the northern polar regions.

Habitat: Bowhead whales are accustomed to the icy waters found in the northern polar region and can navigate waters where there is a lot of ice.

Diet: Bowheads feed both near the surface and on the ocean floor. This gives them a highly varied diet of small marine animals. They eat as many as sixty different species.

Behavior and reproduction: Bowhead whales swim slowly and migrate with the forming and melting of ice in the northern pole region. In females pregnancy lasts fourteen months, and young are fed for a year after birth.

Bowhead whales and people: Inuit in Alaska have hunted and eaten bowhead whales for centuries. During the nineteenth century, bowhead whales were hunted commercially by a number of countries. This commercial whaling was one of the reasons that people first began to explore the Arctic region.

Conservation status: It is estimated that 10,000 bowheads still exist, and they are considered at low risk for extinction. However, certain populations have been greatly diminished and it is questionable whether the few animals left in these areas will be able to recover their once great numbers. ∎

NORTH ATLANTIC RIGHT WHALE (Eubalaena glacialis): SPECIES ACCOUNTS

Physical characteristics: North Atlantic right whales are usually 43 to 53 feet (13 to 16 meters) in length and can weigh up to 100 tons (91 metric tons). They are black, but can have white areas on their belly and chin. Like other right whales, they have rough areas of skin that appear bumpy around their head. Barnacles and whale lice live in these bumps.

Geographic range: North Atlantic right whales are found throughout the seas and oceans of the Northern Hemisphere.

Habitat: These whales spend most of their time in shallow coastal waters. They migrate between cold polar waters for feeding and warmer southern waters for birthing and feeding their young.

Diet: North Atlantic right whales feed on almost any small marine animal that it can filter through its baleen. They are known to feed at the surface and to also dive in order to feed off the ocean floor where the water is not too deep.

Behavior and reproduction: These whales usually dive for ten to twenty minutes. They are slow swimmers. Males compete over a female by pushing and shoving each other. The young are born in the warmer waters during winter and they are fed by their mother for a year after birth.

North Atlantic right whales and people: North Atlantic right whales have been hunted for almost a thousand years because of the meat, oil, and baleen that they can provide. Today large amounts of money are spent on preserving and restoring the small remaining population. They are also an important part of the whale watching industry.

Conservation status: North Atlantic right whales are Endangered. It is estimated that fewer than 250 exist in the world today. Because of accidents with fishing vessels and accidental entanglement in fishing nets, these whales have had a difficult time recovering their numbers. ∎