Northern Bottlenose Whale (Hyperoodon ampullatus)

Did You Know?

· Northern bottlenose whales' scientific name (Hyperoodon ampullatus) is derived from the Latin word ampulla for the "bottle"-shape of the beak.

· Northern bottlenose whales are the most extensively studied of the beaked whales because the whaling industry made carcasses available for scientists to examine.

· Northern bottlenose whales are very curious and often attracted to ships, which made them easy targets for whalers long ago.

Status
MMPA - Northern bottlenose whales, like all marine mammals, are protected under the MMPA.

Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Ziphiidae
Genus: Hyperoodon
Species: ampullatus

Species Description
Northern bottlenose whales are the largest members of the beaked whale family (Ziphiidae) in the North Atlantic Ocean. As adults, northern bottlenose whales can reach lengths of approximately 32 ft (9.8 m) and weigh up to 17,000 lbs (7,500 kg). Males may be slightly larger than females.

Northern bottlenose whales have a large, long, robust body with a small, triangular, "falcate" "dorsal" fin that is located far down (about two-thirds) the animal's back. The whale's head has a distinctive bulbous "melon" and a well-defined bottle-shaped beak; however, these characteristics may vary with sex and age. The lighter-colored melon and forehead become steeper and flatter as the whale ages. Adult males have a pair of relatively small, conical yet visible teeth that angle slightly forward, located on the tip of the lower jaw. While at the ocean surface, these cetaceans produce fairly small, bushy blows every 30-40 seconds that are about 3.3 ft (1 m) tall and visible from a significant distance. Their coloration varies from dark gray to brownish to olive, and their skin may appear lightly mottled and covered with scars and/or other markings. The dorsal side is darker than the ventral side, giving it a counter-shading appearance.

Many species of beaked whales (especially those in the genus Mesoplodon) are very difficult to distinguish (even when dead). At sea, they are challenging to observe and identify to the species level due to their cryptic, skittish behavior, a low profile, and a small, inconspicuous blow at the waters surface; therefore, much of the available characterization for beaked whales is to genus level only. Uncertainty regarding species identification of beaked whales often exists because of a lack of easily discernable or distinct physical characteristics.

Northern bottlenose whales are usually found individually or in social groups averaging between 4-10 individuals, but have been occasionally seen in larger groups and loose aggregations of up to 50 animals. Groups may consist of various combinations and/or be segregated depending on age, sex, or life stage. Males are known to be combative with each other, using their large heads to "butt" one another (Jefferson et al.2008).

Regular dives of Northern bottlenose whales range from 10-60 minutes, commonly reaching depths of at least 2,600-5,000 ft (800-1,500 m), but they are likely capable of diving and holding their breath for up to 2 hours. While diving, they feed near the ocean bottom mostly on deep-sea cephalopods (e.g., squid), fish, shrimp, sea cucumbers, and sea stars. Juvenile animals may feed on prey closer to the surface.

Northern bottlenose whales reach sexual maturity between 7-11 years. A sexually mature female will give birth to a single calf every two or more years during the spring or summer (usually between the months of April and August) after a gestation period of about 12 months. Newborn calves are about 10-11.5 ft (3-3.5 m) in length and weigh 660 lbs (300 kg). These whales have an estimated lifespan of at least 37 years.

Habitat
Northern bottlenose whales prefer cold, deep, temperate to sub-arctic oceanic waters usually greater than 6,500 ft (2,000 m). This species is often associated with steep underwater geologic structures such as submarine canyons, seamounts, and continental slopes.

Distribution
Northern bottlenose whales occur throughout the North Atlantic Ocean and range from New England, Canada, Greenland, Iceland, England, and Europe up to Spitzbergen and down to the Azores and northern Africa (Canary Islands). They have been sighted from 30° North to close to the ice edge in the Arctic. Long term studies of a resident group off of Nova Scotia have been conducted. "Strandings" of this species have occurred in the Baltic Sea, Bay of Fundy, and Rhode Island. This species is capable of traveling distances of more than 600 miles (1,000 km).

Population Trends
For management purposes, northern bottlenose whales inhabiting U.S. waters have been placed in the Western North Atlantic stock. The total abundance of this species off the eastern U.S. coast is unknown and there are insufficient data to determine population trends. The estimated number of animals in the eastern North Atlantic is about 40,000 individuals and 5,000 around the Faroe Islands and Iceland. Studies estimate the year-round resident population size of this species at "The Gully," a submarine canyon located near Nova Scotia, Canada, is about 130-230 animals. Northern bottlenose whales are also commonly observed in the Davis Strait off of northern Labrador, Canada.

Threats
After the discovery of "spermaceti" in bottlenose whales, a commercial whaling fishery developed in the 1800s and 1900s and more than 80,000 were killed. In Canada and Norway, these whales were hunted for meat and oil until the population was depleted. Whalers exploited the curiosity and social bonds of these animals; whales were often attracted to stationary vessels and stayed with wounded or injured members of their pod. For the last several decades, they have remained unexploited, with the exception of a few animals killed in the Faroe Islands drive fishery. This species of beaked whales may be sensitive to underwater sounds and anthropogenic noise. Anthropogenic noise levels in the world's oceans are an increasing habitat concern, particularly for deep-diving cetaceans like northern bottlenose beaked whales that use sound to feed, communicate, and navigate in the ocean.

Conservation Efforts
The International Union for Conservation of Nature and Natural Resources (IUCN's) Red List of Threatened Species considers this species "Lower Risk Conservation Dependent."

Regulatory Overview
This species is protected under the Marine Mammal Protection Act of 1972, as amended.

Key Documents
(All documents are in PDF format.)

Title	Federal Register	Date
Stock Assessment Reports	n/a	various

More Information

References:

Reeves, R. R., P. A. Folkens, et al. (2002). Guide to Marine Mammals of the World. New York, Alfred A. Knopf. p. 268-271.
Jefferson, T. A, M. A. Webber, and R. L. Pitman. (2008). Marine Mammals of the World, A Comprehensive Guide to their Identification. Amsterdam, Elsevier. p. 93-95.