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The Whales Cetacean Classification Cetaceans Right Whales Right Whales Northern and southern are probably 1 species but unresolved at this point No external differences Southern Right whales are larger Right whale identifying characteristics No dorsal fin Heavy body, black color
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Right Whales • Northern and southern are probably 1 species but unresolved at this point • No external differences • Southern Right whales are larger
Right whale identifying characteristics • No dorsal fin • Heavy body, black color • Large head ¼ body length, strongly arched up • Bowed lower jaws close over rostrum • Callousities on rostrum, chin , sides of head, & lip (bonnet on rostrum) • Flippers large and broad
PHYSICAL DESCRIPTION The right whale is a large, bulky baleen whale of unusual appearance. Its upper and lower jaws are highly curved, allowing its long baleen plates to be enclosed while swimming. Its rostrum (upper jaw) is narrow and is often covered by "callosities," hardened patches of skin that occur in the facial area • COLOR Right whales are black all over except for the belly, where there is often a white patch. Wounds and scars may appear bright orange because they become infested with whale lice, or cyamids. The callosities, which are also found near the blowholes, above the eyes, and on the chin and upper lip, are black or gray but appear white because of cyamid coverage.
Eating and Migration • Right whales feed by skimming through concentrations of krill. • 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 Whale Range temperate waters worldwidelargest group winters off Argentina
Reproduction • 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.
The “right” whale to hunt • 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.
LENGTH AND WEIGHT • Adult right whales are generally 35-55 feet (10.7-16.8 m) long. The largest individuals known have measured 60 feet (18.3 m) long and weighed 117 tons (106,500 kg). • Females are larger than males.
Right Whale Behaviors • Slow swimmers • Tendency to form herds of 20 to 100 • Recovery of numbers is slow • The species may not recover
Bowhead Whale • 65 feet long; 110 tons; 14 foot baleen • Protected since 1935 • Pre-exploitation population = 65,000 • Today’s population = 7000 all in the Artic Ocean • Main diet - plankton
Bowhead Whaleidentifying characteristics • Heavy body, black in color • Enormous head 1/3 body length • Strongly bowed lower jaw encloses lower jaw • White vest on chin
Length and Weight • Adult males reach physical maturity at 50 feet (15 m) and may weigh in excess of 60 tons (54,431 kg). Sexual maturity is reached at 38 feet (11.6 m). • Adult females are slightly larger than males at both physical and sexual maturity. Maximum length exceeds 60 feet (18.3 m).
Bowhead range: Artic Ocean onlythey have an affinity to the edge of the polar ice cap
Bowhead behaviors & hunting • Singly or in groups up to 6 • American Inuit (Eskimos) still hunt them as of 1990 they were allowed 24 strikes/year • Allowable strikes: ’96=67, ’97=66 ’98=65 • Total kill ’95-’98 = 204 • 2000 = 42
PHYSICAL DESCRIPTION Although the pygmy right whale is classified with the other right whales (northern and southern right whales and the bowheads), the only feature that all these species have in common is the shape of the mouth. Its upper jaw is arched while the lower jaw is bowed - a feature that seems to become more pronounced with age. Its lower jaw extends slightly beyond the upper jaw. Two indistinct grooves are situated lengthwise in the area of the throat which are similar to the throat grooves of the gray whale. This whale has a small head which takes up only 1/4 its total body length. The blow is small and not very noticeable. There are 210-230 baleen plates on each side of the pygmy right whale's upper jaw. These plates are yellowish-white with a dark brown marginal band on the edge. The baleen plates are up to 27 inches long (69 cm) and are said to be more flexible and stronger than those of any other species of baleen whale. On the side of the body, the animal has two distinct stripe-like coloration "chevrons."
Pygmy Right Whale • 21 feet long & 5 tons is the largest ever known • Population numbers = unknown • Rare whales – no numbers available • Not hunted – too small
Pygmy Right Whale identifying characteristics • Bowed lower jaw • Small head for a Right Whale • Small dorsal fin • Black color • Flippers usually far back on body
LENGTH AND WEIGHT • The length of both sexes averages 20 feet (6.1 m). • The largest known female pygmy right whale was recorded at 21 feet (6.4 m). • The weight of this whale has been estimated at about 5 tons (4500 kg). • Males are slightly smaller than females.
Pygmy Right Whale Rangeall southern hemisphere S. Australia to S. Africa
Pygmy Right Whale behaviors • Only 1 whale ever seen alive • 30 dead whales have been examined by scientists
STATUS Population past or present is not known. Whether there aren't very many of them or whether their habits make them difficult to be seen is a matter of speculation. These whales have never been hunted commercially or by aboriginal hunters.
LENGTH AND WEIGHT • Adult males reach lengths of 49-59 feet (15-18 m) and weigh up to 35-45 tons (31,750-40,800 kgs). • Adult females are much smaller, growing to about 36 feet (11 m) and a maximum weight of 13-14 tons (12,000-12,700 kg).
Sperm Whale NATURAL HISTORY • The sperm whale is the deepest diver of the great whales and can descend to depths of over 3,300 feet (1000 m) and stay submerged for over an hour. Average dives are 20-50 minutes long to a depth of 980-1,970 feet (300-600 m). • At such great depths there is little or no solar light. However, organisms at these depths may produce biochemical light (bioluminescence). Sperm whales use their highly developed echolocation ability to locate food and to navigate, making nearly constant clicking sounds that pulse through the water. Sperm whales communicate using "morse-code" like patterns of clicks called codas. • There is also a theory that sperm whales may stun their prey with a burst of sound.