North Atlantic right whale

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North Atlantic right whale[1]
Mother and calf
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Balaenidae
Genus: Eubalaena
Species: E. glacialis
(Müller, 1776)
Binomial name
Eubalaena glacialis
Range map
Synonyms
  • biscayensis (Eschricht, 1860)
  • nordcaper (Lacépède, 1804)

The North Atlantic right whale (Eubalaena glacialis which means "good, or true, whale of the ice") is a baleen whale, one of three right whale species belonging to the genus Eubalaena,[1] formerly classified as a single species.

About four hundred right whales live in the North Atlantic Ocean. They migrate between feeding grounds in the Gulf of Maine and their winter calving areas off Georgia and Florida, an ocean area with heavy shipping traffic.

Like other right whales, the North Atlantic right whale is readily distinguished from other whales by the callosities on its head, a broad back without a dorsal fin, and a long arching mouth that begins above the eye. The body of the whale is very dark grey or black, occasionally with white patches on the belly. The right whale's callosities appear white due to large colonies of cyamids or whale lice.

Adult right whales average 35–55 feet (11–17 m) in length and weigh up to seventy tons (63,500 kg); the largest measured specimens have been 60 feet (18 m) long and 117 tonnes (115 LT; 129 ST). Females are larger than males.

Forty percent of a right whale's body weight is blubber, which is of relatively low density. Consequently, unlike many other species of whale, dead right whales float.

There is little data on their life span, but it is believed to be at least fifty years, and some may live more than a century.

Contents

Reproduction

They first give birth at age nine or ten after a year-long gestation; the interval between births seems to have increased in recent years and now averages three to six years. Calves are 13–15 feet (4.0–4.6 m) long at birth and weigh approximately 3,000 pounds (1,361 kg).[3]

Feeding

Right whales feed mainly on copepods and other small invertebrates such as krill, pteropods, and larval barnacles, generally by slowly skimming through patches of concentrated prey at or below the ocean surface.[2]

Whaling

Main article: History of whaling

Right whales were so-named because whalers thought they were the "right" whale to hunt. Combined with the right whale's lack of speed through water, feeding habits, and coastal habitat, they were easy to catch, even for whalers equipped only with wooden boats and hand-held harpoons.[4]

Whaling in small wooden boats with hand harpoons was a hazardous enterprise, even when hunting the "right" whale.

Basques were the first to commercially hunt this species. They began whaling in the Bay of Biscay as early as the eleventh century. The whales were hunted initially for their oil but, as meat preservation technology improved, their value as food increased. Basque whalers reached eastern Canada by 1530[5] and the shores of Todos os Santos Bay (in Bahia, Brazil) by 1602. The last Basque whaling voyages were made prior to the commencement of the Seven Year's War (1756–1763). A few attempts were made to revive the trade, but they all failed. Shore whaling continued sporadically into the 19th century.

Setting out from Nantucket and New Bedford in Massachusetts and from Long Island, New York, Americans took up to one hundred right whales each year. By 1750, the population of North Atlantic right whales was, for commercial purposes, depleted. Yankee whalers moved into the South Atlantic before the end of the 18th century.

As it became clear that populations were unsustainable, a worldwide ban on right whaling was adopted in 1937. The ban was largely successful, although some whaling continued in violation of the ban for several decades. Madeira took its last two right whales in 1968.

Threats

The latest reports claim that the greatest danger to the North Atlantic right whale is injury sustained from ship strikes.[6] Between 1970–1999, 35.5% of recorded deaths were attributed to collisions.[4] During 1999–2003, incidents of mortality and serious injury attributed to ship strikes averaged 1 per year. In 2004–2006, that number increased to 2.6.[2] Deaths from collisions is now proving to be an extinction threat.[7]

In 2007, and again on June 1, 2009, the US government changed shipping routes out of Boston in an attempt to reduce collision.[8] NOAA estimates that implementing an "Area To Be Avoided" (ATBA) and narrowing the "Traffic Separation Scheme" (TSS) by one nautical mile will reduce the relative risk of right whale ship strikes by 74% during April–July (63% from the ATBA and 11% from the narrowing of the TSS).[9]

Population and distribution

About four hundred North Atlantic right whales exist, almost all living in the western North Atlantic Ocean. In spring, summer and autumn, they feed in a range stretching from New York to Nova Scotia. Particularly popular feeding areas are the Bay of Fundy, the Gulf of Maine and Cape Cod Bay. In winter, they head south towards Georgia and Florida to give birth.

There have been a few sightings further east over the past few decades, with several sightings close to Iceland in 2003. There was speculation that these could be the remains of a virtually extinct Eastern Atlantic stock, but examination of old whalers' records suggest that they are more likely to be strays from further west.[5] A few are sighted regularly in waters adjacent to Norway, Ireland, Spain, Portugal, and the Canary Islands.

In January 2009, one animal was sighted off Pico Island, Azores, the first confirmed appearance there since 1888. It was later revealed that this animal, which was named as "Pico", is a female from the western Atlantic group.[10] Right whales have rarely been observed in the Mediterranean Sea, near Italy[11] and Portugal.[12] The Norway sightings appear to be of strays from the western Atlantic stock.[13] In 2009, right whales appear in waters around Greenland[14] although their origin was not confirmed.[15] Prior to this. no right whales had been killed or confirmed present off the coast of Greenland for around two hundred years. [16]

In early 2009, scientists recorded a record number of births among the western North Atlantic population. 39 new calves were recorded. were born off the Atlantic coast of Florida and Georgia.

"Right whales, for the first time in a long time, are doing their part: they're having the babies; they're having record numbers of babies," said Monica Zani, an assistant scientist at the New England Aquarium who works with right whales. "We need to be vigilant and still do our part to prevent the whales from being killed."[3]

Conservation status

The species is listed as endangered by the U.S. government National Marine Fisheries Service under the U.S. Endangered Species Act.

References

  1. ^ a b Mead, James G. and Robert L. Brownell, Jr (November 16, 2005). Wilson, D. E., and Reeder, D. M. (eds). ed. Mammal Species of the World (3rd edition ed.). Johns Hopkins University Press. pp. 723–743. ISBN 0-801-88221-4. http://www.bucknell.edu/msw3/browse.asp?id=14300008. 
  2. ^ a b c Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N. (2008) Eubalaena glacialis In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1. www.iucnredlist.org Retrieved on 22 August 2009.
  3. ^ a b John D. Sutter (April 3, 2009). "Endangered right whales appear to be on the rebound". http://www.cnn.com/2009/TECH/science/04/03/right.whale.rebound/index.html. Retrieved 2009-12-29. 
  4. ^ a b Ward-Geiger, L.I.; Silber, G.K., Baumstark, R.D., & Pulfer, T.L. (3 March, 2005) (PDF). Characterization of Ship Traffic in Right Whale Critical Habitat. Taylor & Francis Inc.. doi:10.1080/08920750590951965. ISSN 0892-0753. http://www.nmfs.noaa.gov/pr/pdfs/shipstrike/critical_habitat_traffic.pdf. Retrieved 22 August, 2009. 
  5. ^ a b Kenney, Robert D. (2002). "North Atlantic, North Pacific and Southern Right Whales". in William F. Perrin, Bernd Wursig and J. G. M. Thewissen. The Encyclopedia of Marine Mammals. Academic Press. pp. 806–813. ISBN 0-12-551340-2. 
  6. ^ Vanderlaan & Taggart (2007). "Vessel collisions with whales: the probability of lethal injury based on vessel speed" (PDF). Mar Mam. Sci. http://www.phys.ocean.dal.ca/~taggart/Publications/Vanderlaan_Taggart_MarMamSci-23_2007.pdf. Retrieved 2008-05-10. 
  7. ^ "Shipping threat to endangered whale". BBC News Online (BBC). 28 August, 2001. http://news.bbc.co.uk/2/hi/science/nature/1513434.stm. 
  8. ^ "North Atlantic Right Whale Ship Strike Reduction". Office of Protected Resources – NOAA Fisheries. http://www.nmfs.noaa.gov/pr/shipstrike/. Retrieved 2009-08-22. 
  9. ^ National Oceanic and Atmospheric Administration (2009-05-26). "Changes in Vessel Operations May Reduce Risk of Endangered Whale Shipstrikes". http://www.noaanews.noaa.gov/stories2009/20090526_shippinglanes.html. Retrieved 2009-08-22. 
  10. ^ "First North Atlantic right whale sighting in Azores since 1888". WildlifeExtra.com. http://www.wildlifeextra.com/go/news/azores-whales009.html#cr. 
  11. ^ Notarbartolo di Sciara, G., E. Politi, A. Bayed, P.-C. Beaubrun and A. Knowlton (1998). "A winter cetacean survey off Southern Morocco, with a special emphasis on suitable habitats for wintering right whales". Sci. Rep. Int. Whaling Commission, SC/49/O3, 48: 547–550. 
  12. ^ Martin AR, Walker FJ (1996-05-16). "SIGHTING OF A RIGHT WHALE (EUBALAENA GLACIALIS) WITH CALF OFF S. W. PORTUGAL". Marine Mammal Science 13 (1): 139. doi:10.1111/j.1748-7692.1997.tb00617.x. http://www3.interscience.wiley.com/journal/119947961/abstract?CRETRY=1&SRETRY=0. Retrieved 2006-10-26. 
  13. ^ Jacobsen KO, Marx M, Øien N (2003-05-21). "TWO-WAY TRANS-ATLANTIC MIGRATION OF A NORTH ATLANTIC RIGHT WHALE (EUBALAENA GLACIALIS)". Marine Mammal Science 20 (1): 161. doi:10.1111/j.1748-7692.2004.tb01147.x. http://www3.interscience.wiley.com/journal/119922229/abstract. Retrieved 2006-10-26. 
  14. ^ National Oceanic and Atmospheric Administration (May 20, 2009). "NOAA Expedition Hears Endangered North Atlantic Right Whales off Greenland". http://www.noaanews.noaa.gov/stories2009/20090520_rightwhales.html#cr. 
  15. ^ Newman, Dennis (May 20, 2009). "OSU Researchers Discover 'Extinct' Whales". Natural Oregon. http://www.naturaloregon.org/2009/05/20/osu-researchers-discover-extinct-whales/. 
  16. ^ SaraJean (2009-25-05). "Greenland: New Home for Right Whales". http://whalecity.com/news/2009/05/25/greenland-new-home-right-whales. Retrieved 2009-12-29. 

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