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North Atlantic Right Whale, Eubalaena glacialis

The North Atlantic right whale (Eubalaena glacialis), also known as the black right whale or the northern right whale, is one of three right whales in the Eubalaena genus. It can be found in a small population of about 396 individuals in the western North Atlantic. If it does occur in the eastern North Atlantic, experts assert that it only numbers in the tens, making it nearly extinct in that area. This species migrates into the western North Atlantic to feed in the spring, summer, and fall seasons with a range that extends from Nova Scotia to New York. In this area of its range, it prefers to feed in The Gulf of Main, Cape Cod Bay, and the Bay of Fundy. During the winter season, this species migrates south into the warmer waters near Florida and Georgia to give birth to calves.

One North Atlantic right whale was spotted off Pico Island, Azores. This was the first sighting of the species in that area since 1888, and the whale was found to be a female named Pico, who originated from the western Atlantic group. Right whales occasionally appear in the Mediterranean Sea, with one confirmed sighting in the 20th century. A petty officer in the Italian Navy caught pictures of this whale about 8.1 miles off the coast of Sant’ Antioco, a small island near southwestern Sardinia. Prior to 2009, right whales had not been seen near Greenland for two hundred years, but a few were spotted in that year whose origin could not be confirmed.

The North Atlantic right whale can reach an average body length between 43 and 52 feet and a weight between 44 and 77 short tons, with females typically growing larger than males. Forty percent of this species’ body weight is comprised of blubber, and because of this, dead individuals will float. This species can be distinguished from other whales by lack of a dorsal fin, an arching mouth that extends from the eyes, and the callosities located on the head. Most of this whale’s body is dark grey or black in color, with white spots sometimes occurring on the underbelly.

The North Atlantic right whale is able to breed at nine years of age, and after a pregnancy period of one year, one calf is born. Calves are born with a body length of up to 15 feet, with a weight of about 3,000 pounds. The diet of this species consists of copepods and small invertebrates like pteropods, krill, and larval barnacles. It sucks food into its mouth by skimming just below the surface of the water or lower, where concentrations of its preferred food types occur. There is little known about the lifespan of this species, but it is thought to live an average of fifty years and may even live for over one hundred years.

Birth rates of the North Atlantic right whale are recorded each year, and in 2009, it was found that 39 calves were born off the coasts of Georgia and Florida. In 2012, however, birth rates were found to be extremely low, with a recorded number of only seven calves. One of these calves is thought to have died. In the last ten years, the average amount of births per year is ten, causing experts to believe that a decrease in the amount of food in the whale’s summer breeding waters in 2010, coupled with its slow reproductive rate, may have caused this low number of calves.

All right whale species were given their common name by whalers, who thought the species was the “right” whale to kill. This was due to its tendency to float after being killed, allowing whalers to easily strip blubber directly from the whale. This species was very easy to catch, because it moved slowly through the water close to the shore. Whalers often used only wooden boats and small, hand-held harpoons to kill the whales.

The first commercial hunting of the North Atlantic right whale was conducted by the Basques people in the eleventh century, in the Bay of Biscay. Initially hunted only for its use in oil, it was eventually hunted as a source of food after meat preservation techniques improved. By 1530, Basque whalers reached Canada in search of right whales. Commercial whaling of this species ended before the Seven Years’ War, which lasted from 1756 to 1763, after which some whalers attempted to recover the commercial industry, but these attempts failed. Whalers continued to hunt this species along the coastline occasionally until the 19th century. It was once thought that Basque whalers overhunted the species in Canadian waters, causing the major decline in their numbers, but this was later disproved by genetic studies.

American whalers first started hunting the North Atlantic right whale from New Bedford and Nantucket in Massachusetts and Long Island, New York. One hundred right whales were killed by American whalers each year, with a recorded twenty-nine whales being killed in one day in January of 1700. The North Atlantic population of right whales was nearly exhausted by 1750, so American whalers moved into the South Atlantic to hunt whales until the 1800’s. By studying past records and current information about this species, experts have found that it may have numbered less than one hundred individuals by 1935. In 1937, whaling of right whales became illegal across the globe, although poaching did occur over the next few decades.

It has been found that between the years of 1970 to 2006, humans have caused 48 percent of the 73 deaths of North Atlantic right whales recorded during that time. One study conducted in 2001 showed that the population numbers of this species have been declining since 1990, and at the current rate of decline with no conservation efforts, it is thought that this whale could become extinct within the next 200 years. Besides outside threats, this species of whale suffers from a limited gene pool caused by small population numbers and a slow reproductive rate. Because the mortality rate of this whale is so high, these threats and others can be devastating. However, if just a few deaths can be prevented, it is thought that population numbers could increase. Experts assert that saving two females each year could greatly bolster the species. With this information, it has been found that human caused threats, like ship strikes and fishing nets, cause a greater threat to this whale than other species.

The second greatest threat to the North Atlantic right whale is becoming entangled in fishing nets. These nets are fixed to the ocean floor and include cod traps, lobster pots, and groundfish gillnet gear. Eight deaths were caused by fishing nets between the years of 1970 and 2006, comprising eleven percent of 73 deaths. Between 1986 and 2005, sixty-one entanglements were reported, including the eight deaths, but it is though that these numbers do show the complete impact of fishing gear on this species. Because these nets hold the whales underwater, they do not float to the surface after perishing, so many deaths may have gone unrecorded.

Not all whales die from becoming entangled in fishing gear, but it is thought that whales that do survive suffer from other threats. These include a weakened state, low fertility, and an increased risk of other accidents. By studying the scarring of whales that have survived entanglements, it has been found that between the years of 1980 to 2002, at least 75 percent of whales examined showed signs of entanglement. This shows that studying the scarification of whales may better assess the actual amount of whales trapped by nets. Through these studies, it is thought that 14 to 51 percent of whales may become trapped in fishing gear.

The North Atlantic right whale is protected in southeast waters of the United States by the National Marine Fisheries Service (NMFS), which offer the whales protection from entanglement in a key breeding area. By revising regulations, the NMFS was able to utilize the Atlantic Large Whale Take Reduction Plan (ALWTRP) to restrict fishing in the waters around Georgia, North Carolina, and northern Florida. These restrictions prevent the use or ownership of gillnet fishing gear each year, beginning on November 15, which coincides with the breeding and calving season of this species.

If these restrictions fail, there are disentanglement procedures that can be used to save the North Atlantic right whale from death. Although these efforts do not always work, they have proven to be vital to the whale’s survival. Between the years of 2004 and 2008, there were four recorded cases of these procedures saving a right whale from death caused by fishing gear. In 2009 and 2011, experts successfully used a sedative to calm an entangled whale, allowing the scientists to detach the whale quickly and reducing the amount of stress of the whale. After placing a tracking device on the whale, experts gave it an antibiotic to treat the wounds caused by the nets and then reversed its sedation.

The greatest threat to the North Atlantic right whale is ship strikes. Between the years of 1970 and 2006, 37 percent of all documented deaths of this species were caused by ship strikes. Between 1999 and 2003, at least one whale per year was injured or killed by ship strikes, and this number increased to about two between 2004 and 2006. It is thought that these numbers do not represent the entire amount of whales injured or killed by ships, because these incidents only occurred off the shore and not in deep ocean waters. In order to reduce the amount of ship strikes, the International Maritime Organization moved the Traffic Separation Scheme, or shipping lanes, from the  Bay of Fundy and surrounding areas to an area where these whales to not often traffic. A similar measure was taken in 2006, when the US National Oceanic and Atmospheric Administration (NOAA) recognized a new set of shipping routes that could better protect right whales in eastern waters of the United States. It is thought that if the NOAA makes this area an “area to be avoided” and reduces the Traffic Separation Scheme by one nautical mile, the threat of ship strikes to right whales could be reduced by 74 percent between the months of April to July.

A study conducted in 2011 showed that right whales could become psychologically stressed if exposed to low frequency noises caused by ships. Another hindrance to the North Atlantic right whale is Naval training that occurs within their calving range. The Navy proposed the construction of an underwater sonar-training center directly across from the calving waters of this species. Despite legal actions taken by conservation and environmental groups, like the Natural Resources Defense Council, the Navy was given permission to continue with their plans.

The North Atlantic right whale can be found in the Convention on the Conservation of Migratory Species of Wild Animals in Appendix I. This gives it an endangered status worldwide and means that this species needs conservation in every aspect of its life. The CMS encourages governments within the range of this species, or range states, to take action in protecting it and other Appendix I species. Because of this, whales located in a small area of the eastern Atlantic are protected by the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area or ACCOBAMS. This species can also be found in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which prevents the import, export, and monetary trade of any specimen or product derived from these whales. Specimens being used for scientific purposes are an exception to this regulation. It is listed as an “Endangered” species in the Endangered Species Act in the United States, and as “depleted” in the Marine Mammal Protection Act. The North Atlantic right whale appears on the IUCN Red List with a conservation status of “Endangered.”

Image Caption: North Atlantic Right Whale. Credit: Pcb21/Wikipedia

North Atlantic Right Whale Eubalaena glacialis


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