The bowhead whale has a robust, dark-colored body, no dorsal fin and a strongly bowed lower jaw and narrow upper jaw. Its baleen, the longest of any whale at 3 m (9.8 ft), strains tiny prey from the water. The whale has a massive bony skull which it uses to break through the Arctic ice to breathe. Inuit hunters have reported them surfacing through 60 cm (24 in) of ice. The bowhead whale has paired blowholes that spout a blow 20 feet high. The bowhead may grow up to 14–18 m (46–59 ft) and weigh from 30,000 to 60,000 kg (66,000 to 130,000 lb) in adulthood.[12] It is of comparable size to the three species of right whale. The largest bowhead yet reported was 21.2 m (70 ft) for a giant caught off Spitsbergen, Norway. This specimen was later estimated to have weighed approximately 133 t (290,000 lb).[13] Females are larger than males. Its blubber is the thickest of any animal, averaging 43–50 cm (17–20 in).
Arctic bowhead whales have lost a significant portion of their genetic diversity in the past 500 years. Hundreds of DNA samples from living whales and from baleen used in vessels, toys and housing materialFragmented sentence. Bowheads crossed ice-covered inlets and straits to exchange genes between Atlantic and Pacific populations. This conclusion derived from analyzing maternal lineage using mitochondrial DNA, most likely because of whaling and climatic cooling between the 16th and 19th centuries — known as the Little Ice Age — which reduced the whales’ summer habitat.[14]
[edit] Life history
