Beaked Whales: Ziphiidae

Physical characteristics: The northern bottlenosed whale is also called the Atlantic bottlenosed whale, the flathead, or bottlehead. Males reach a maximum length of about 30 feet (9 meters), while females grow only to about 25 feet (7.5 meters). In addition, males develop a large, bulging forehead. The forehead of the female is much smoother. Both sexes have a short beak or snout and range in color from dark brown on the back to pale yellow on the belly. Mature males often have a white or light patch on the forehead. Males have one pair of small teeth in the lower jaw. In females, the teeth never break through the skin.

Geographic range: These whales are found in pockets in the North Atlantic off Norway, Finland, Greenland, Iceland, and as far south as Spain and North Africa on the European side. On North American side, they are found off the Labrador and Nova Scotia in Canada and as far south as Rhode Island in the United States. One particularly well-studied group lives in an area called the Gully, a deep canyon off Sable Island, Nova Scotia.

Habitat: Northern bottlenosed whales prefer deep, cold to moderate (32 to 63°F; 0 to 17°C) water, and sometimes travel into broken ice fields. They are usually seen in areas where the water is more than 3,300 feet (1,000 meters) deep and are more common in the northern part of their range than in the southern part.

Diet: Northern bottlenosed whales feed near or at the ocean floor. They eat mainly squid, but will also eat fish, sea cucumbers, starfish, and shrimp. Like all toothed whales, they use echolocation to hunt their prey.

Behavior and reproduction: Northern bottlenosed whales live in groups of four to ten individuals. They are excellent deep divers and have been known to regularly dive to depths of between 2,600 and 4,600 feet (800-1400 meters) and stay under water for seventy minutes. These whales seem to migrate north in the summer and south in the winter in a regular pattern.

Not much is known about bottlenosed whale reproduction, although it is believed that males buck each other in the head in competitions to breed with females. Females are thought to be sexually mature (able to reproduce) at about seven to ten years old. A single calf is born in the spring or early summer after a twelve-month pregnancy. It stays with its mother and nurses for at least one year. Northern bottlenosed whales are thought to live for thirty to forty years.

Northern bottlenosed whales and people: These whales have few interactions with people.

Conservation status: These whales were hunted from the 1880s until the 1970s, mostly in Norway. One estimate is that Norwegian fisherman killed 60,000 northern bottlenosed whales between 1880 and 1930 and 5800 from 1930 to 1973. Hunting stopped in 1973, and in 1977 the whale became legally protected from hunting. Another threat to this species is human development. In Nova Scotia, a large undersea oil and gas field is being developed only about 3 miles (5 kilometers) from the Gully where these whales live. ∎