Massachusetts Marine Mammal

Right Whale

(Eubabalena glacialis)

Adopted in 1980.

The Right Whale, Eubabalena Glacialis, was adopted  in March 1980. It was so called because the flourishing whaling industry in Massachusetts found the cetacean the "right" whale to hunt, especially before 1750. Unfortunately, the large, slow-moving mammal, which is found nearer shore than many other whales, was hunted nearly to extinction and is only now rebuilding its population.

A large, blackish whale with the following features: no dorsal fin; head huge, about one-fourth of total length; baleen (whalebone) about 2 m long, 30 cm wide, and between 200 and 250 in number on each side of mouth; closure of mouth highly arched; no furrows on the throat; prominent, large, wartlike areas (called bonnets), the one near tip of snout largest. Total length of adults, 14-17 m; weight, 20-30 metric tons.

Right whales were so named by early whalers because they were the "right" whale to kill — they are slow swimmers and were thus easily caught, floated when dead, and produced large quantities of oil and baleen. Consequently, right whales were decimated early by the world's whaling industries and have yet to recover.

Right whales spend spring, summer, and autumn at high latitude feeding grounds and migrate to more southerly, warmer waters in winter for mating and calving. Northern and southern populations do not interbreed due to asynchronous seasons between the hemispheres.

Right whales produce a variety of vocal sounds as well as percussive sounds of breaching, flipper slapping, and tail slapping. A distinctive clacking sound has been described for these whales as they feed at the surface. Termed the "baleen rattle," this sound is produced by small wavelets rattling the baleen plates when they are partially held out of water. Right whale sounds appear to differ with changing behavior and, thus, may be important in communication. As with other baleen whales, right whales probably do not echolocate.

Right whales feed by skimming through concentrations of krill. They have been seen feeding at depths ranging from the surface down to 10 m although they may also feed at deeper levels. Location of krill concentrations in the water column probably determines feeding depth.

After a one-year gestation period, females give birth to a single calf in winter. Calves are 5-6 m in length at birth but grow rapidly during the subsequent period of lactation, which lasts about 13 months. Calves remain with their mothers for 2-3 years following weaning and probably reach sexual maturity at about 10 years of age. Females give birth at 2 to 7 year intervals.