Monday, July 30, 2007

Monodontids fact sheet


The beluga and the narwhal are the only two living species in the family Monodontidae, they are medium sized whales with almost no beak, broad flippers and no dorsal fin.

Beluga or white whale
(Delphinapterus leucas)

The beluga is completely white and it not easily confused with any other whale. The calves are grey when they are born but get whiter with age. Sometimes belugas can look yellowish before shedding skin. They live in the Arctic and sub-arctic areas. Males can grow to 5,5 m and 1 600 kg (max. 1 900 kg) and females 4,1 m. The beluga has eight or nine pairs of peg-like teeth in each jaw. They live in groups of about 10 individuals in average but in summer hundreds or thousands of belugas can gather. Belugas got the nickname "canaries of the sea" as they vocalize a lot and they also use echolocation (like other toothed-whales). They can live up to 70-80 years. They get sexually mature at an age of 4 to 7 years for females and 4 to 9 years for males. They give birth to a single calf in average every third year. The calf is about 1,5 m long at birth a weight 80 kg. 
Belugas are good swimmers and can swim as fast as 22 km/h. They can dive to more then 700 m deep and hold their breath for 18 min. Their diet vary due to season, they feed on an variety of fish (ex. Arctic cod, rose fish, salmon, capelin, smelt, sole, flounder, herring) and invertebrates (shrimps, squid and octopus, crabs, clams, sea snails). They eat between 18 and 27 kg per day. 

In other languages
Portuguese: Beluga, baleia branca
Spanish: Beluga
French: Béluga, baleine blanche
Italian: Beluga
German: Weißwal
Dutch: Witte dolfijn, beloega
Swedish: Vitval, beluga
Norwegian: Kvitkval
Danish: Hvithval
Finnish: Maitovalas

Narwhal - The unicorn of the sea
(Monodon monoceros)

Narwhals have a light grey or white base colour and are mottled with dark patches and spots, becoming paler with age. They live in Arctic waters, sharing home with the beluga. They can grow to a length of 5,5 m and weight between 800 and 1 800 kg, males larger then females. The calves are about 1,6 m when born and darker in colour. The calves are nursing for about 20 month. Females becomes sexually mature between 5 to 8 years old and males between 11 and 13 years old. They can live to be 50 years old.
Narwhals have no functional teeth inside their mouth. But a long, spiraled canine-tooth that in males erupts through the left side of the upper jaw extending forward and slightly downwards like a tusk. This tusk can grow to 3,1 m and weight 10 kg, and its hollow inside. Sometimes even females have a tusk (about 15%) or sometimes both the canines erupts through the skin and the "unicorn of the sea" has two tusks (1 in 500).
Narwhals can dive down to 1 500 m and hold their breath for 25 min. They feed on fish (Greenland halibut, polar and arctic cod, redfish) fish eggs and cuttlefish, shrimps and armhook squid.

In other languages
Portuguese: Narval
Spanish: Narval
French: Narval
Italian: Narvàlo
German: Narwal
Dutch: Narwal
Swedish: Narval
Norwegian: Narhval
Danish: Narhval
Finnish: Sarvivalas

Threats to monodontids:
Belugas and narwhals have three enemies: polar bears, orcas (killer whales) and humans - and the last one being their worst threat. The belugas are locally hunted in Beaufort sea, eastern High Arctic of Canada, western Hudson Bay and eastern Berings sea. Hunted for meat, skin, oil and captivity. Another threat is loss of sea ice as ice gives protection from orcas. The narwhal is also still hunted mainly for meat, skin and oil but also ivory. Overfishing and loss of prey is a problem of any marine animal.

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