Humpback Whale (Megaptera novaeangliae)

   

Class: Mammalia
Order: Cetacea
Family:    Balaenopteridae
Size:    Length: 40 to 50 feet (12 to 15 m)
Weight: 85,000 to 90,000 pounds (38,555 to 40,823 kg)
Diet: Plankton and fish such as mackerel, capelin and herring
Distribution: Arctic, Antarctic, Pacific Ocean and Atlantic Oceans
Young:  1 calf every two years
Animal Predators:  Killer whale
IUCN Status: Vulnerable
Terms: Young: Calf   Male: Bull   Female: Cow   Group: Pod
Lifespan: Average lifespan is 50 years

 

Facts/Trivia:

·         The name “humpback” comes from the whale’s tendency to round its back when diving and from the small hump located in front of its dorsal fin. 

·         The humpback whale is the fifth largest of the world’s great whales.

·         The scientific name, Megaptera novaeangliae, means “large wings of New England,” which refers to its long flippers and the place it was first seen.

·         Humpback whales produce a variety of sounds that include the highest and lowest frequencies humans can hear.

 

Description

Humpbacks are black with white markings on their long, wing-like flippers and undersides. The butterfly-shaped tail fluke shows distinctive patterns of grey and white. Humpbacks are often covered in barnacles. They have knobs on their head that vary in size, 14 to 35 grooves that run lengthwise on their throat, and a rounded protrusion on their lower jaw. Rather than teeth, humpback whales have baleen in their mouth, which are rows of bristly plates that resemble a comb. Baleen is made of keratin, the same flexible material found in fingernails and hooves. Humpback females tend to be larger than their male counterparts.

 

Habitat

Humpback whales live in cold areas of the Arctic and Antarctic during the summer. They follow regular migratory patterns, leaving the cold waters where they feed during the spring, summer and fall to winter in shallow tropical waters to breed.

 

Feeding Habits

Humpbacks feed on plankton and fish such as mackerel, capelin and herring. To do this, the whale opens its mouth and then closes it around its prey and the water surrounding the prey, then strains the water out through the bristly baleen plates on the upper jaws, leaving behind only the food. Humpback whales use several distinctive feeding strategies. Some humpback whales feed by swimming in a circle at the surface of the water, blowing bubbles through their blowholes and striking the water with their flukes to make a ring of foam and bubbles around their prey. Then, the whales swim right up through the centre of the bubbles and ingest the prey. 

 

Reproduction

Males compete for access to females and sing elaborate songs to the females to attract them. The females undergo an 11 to 12 month pregnancy, giving birth in warm tropical waters. The newborns, ranging in size from 10 to 16 feet (3 to 4.8 m) in length, drink at least 10 gallons (37 litres) of their mother’s rich milk per day. They weigh an average of 1.5 tons (1,360 kg) at birth, and nearly double that during their first year. They are weaned sometime between five and eight months. 

 

Behaviour

Humpback whales are social animals that live in groups. They are acrobatic whales, making huge leaps out of the water, sometimes even leaping completely clear of the water, and then falling back down into it. They also like to slap their flippers and tail on the surface of the water. Humpbacks can submerge for up to 30 minutes, although they usually dive underneath for only six to seven minutes. When migrating, they tend to follow the coastline, cruising at speeds of three to six miles (4.8 to 9.6 km) per hour, although they can reach up to 20 miles (32 km) per hour for short amounts of time.  

 

Conservation

The estimated worldwide population is 6,000 to 9,000 humpbacks. Their numbers were at an all time low in the early 1900s, and hunting humpbacks in the Antarctic became prohibited from 1939 to 1949. By 1966, the population dropped to less than 1,000 due to commercial whaling. They have since received protection from a number of sources, including the Marine Mammal Protection Act and the Endangered Species Act, which protect them in U.S. waters. The International Whaling Commission, which in 1955 and 1965 put protections in place on humpbacks in the North Atlantic and North Pacific populations respectively, in 1985 placed a worldwide moratorium on commercial whaling, with the exception of inhabitants of western Greenland, who are limited to 10 whales per year. Whaling in Canadian waters is prohibited by The Canadian Whaling Regulations.  

 

Sources

http://animaldiversity.ummz.umich.edu/accounts/megaptera/m._novaeangliae$narrative.html

http://www.aquatic.uoguelph.ca/mammals/whales/accounts/humpback.htm

http://www.cetacea.org/humpback.htm

http://www.oceanoasis.org/fieldguide/mega-nov.html

http://nmml.afsc.noaa.gov/education/cetaceans/humpback1.htm

http://www.nsrl.ttu.edu/tmot1/meganova.htm

http://www.nature.ca/notebooks/english/humpwale.htm

http://www.enature.com/fieldguide/showSpeciesGS.asp?curGroupID=5&searchText=humpback&curPageNum=1&recnum=MA0153

Humpback Wildlife Fact File, IM Pub, US