#WhaleWednesday – North Atlantic Right Whale

 

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The North Atlantic right whale, as some of you may already be aware, has been in the news recently as the Canadian Federal Fisheries officials investigate the death of yet another endangered right whale on the Canadian east coast. The department confirmed on Tuesday August 1, 2017 that a whale was found dead in the Gulf of St. Lawrence after washing ashore on the west coast of Newfoundland. In total the carcasses of 10 endangered right whales have been found in the Gulf since June 7 of this year. Jerry Conway of the Canadian Whale Institute in Campobello, NB, said the deaths are disastrous for an already vulnerable species. “We feel there is tremendous urgency,” he said “This has had catastrophic ramifications on the right whale population, this number of whales being killed when we only know of three calves being born this year. It certainly indicates a rapid decline in the population”

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What are the threats to the North Atlantic right whale? North Atlantic populations have been decimated by historical over exploitation by whaling industry. The species get its name from early whalers, who considered them to be the “right” whales to hunt. Their slower pace, the fact that they come close to land, their tendency to float after being killer and their “productivity” in terms of oil made them lucrative whales to target. Today, the species is threatened by ship collisions, entanglement in fishing nets, and separation from calving areas because of shipping traffic. Since the right whale is found in coastal habitats, it is more likely to suffer impacts of human activity than more open-water cetaceans.

The North Atlantic right whale is mostly found along the Atlantic coast of North America, where it is threatened by entanglement in fishing gear and ship collisions. Some scientists believe these whales have already been extirpated from the eastern North Atlantic and now survive only on the east coast of Canada and the U.S.

The right whale is characterized by a symmetrical skill, paired blowholes, and rows of baleen plates for feeding on plankton. Males can reach up to 12.9m, while females can reach up to 18m and weigh approximately 96, 000 kg or 105tons.  They are a relatively slow swimmer, averaging about 8 km/hr and typically makes a series of 5 or 6 shallow shallow dives, the submerges for around 20 minutes. Right whales emit a number of low frequency sounds, mostly during courtship. It is estimated that they can live longer than 30 years and up to about 75 years.

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This large whale mostly inhabits temperate waters and compared to other similar sized cetaceans is found more often in coastal waters, especially during breeding season.

Whereas groups of North Atlantic right whales once numbered in the hundreds in feeding grounds, nowadays they usually travel alone or in groups of 2-3 sometimes up to about 12. Groups splinter off for feeding, most likely the result of the sheer quantity of food required for each individual whale. These aggregations are not fixed, and individuals have been observed to change groups. One notable exception is in the Bay of Fundy, where up to two thirds of the remaining population aggregates in the summer to feed.

North Atlantic right whales feed mostly on copepods and krill larvae. About 2200-5500 lbs may be consumed every day. The right whale feeds by swimming through a swarm of prey with its mouth open and the head slightly emerging on the surface. Having filtered the prey with its baleen plates, it drives out the water, dive, and swallows the food, as a process known as skimming.

Females breed about once every three to five years. Gestation is about one year and the single calf is nursed for 9-12 months. Pregnant females migrate to area off the coast of Georgia and Florida to give birth between December and March and then migrate north to their feeding grounds in the Bay of Fundy.  Scientists are confident there is at least one other nursery area but have yet to discover it – where these whales mate is also a mystery.

As with other mammals, right whale mothers and their calves display strong attachments, with the calf keeping in close contact with its mother by swimming up on her back or butting her with its head. Sometimes the mother may roll over to hold her calf with her flippers.