Gray whale

Gray whale[1]
Fossil range: Upper Pleistocene - Recent
A gray whale spy-hopping
Size comparison against an average human
Conservation status

Least Concern (IUCN 3.1)[2]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Suborder: Mysticeti
Family: Eschrichtiidae
Ellerman & Morrison-Scott, 1951o
Genus: Eschrichtius
Species: E. robustus
Binomial name
Eschrichtius robustus
Lilljeborg, 1861
Gray whale range

The gray (or grey) whale (Eschrichtius robustus) is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of about 16 meters (52 ft) a weight of 36 tonnes (35 LT; 40 ST) and lives 50–60 years. The common name of the whale comes from the gray patches and white mottling on its dark skin.[3] Gray whales were once called devil fish because of their fighting behavior when hunted . The gray whale is the sole species in the genus Eschrichtius, which in turn is the sole genus in the family Eschrichtiidae. This mammal descended from filter-feeding whales that developed at the beginning of the Oligocene, over 30 million years ago.

The gray whale is distributed in an eastern North Pacific (American) population and a critically endangered western North Pacific (Asian) population. North Atlantic populations were extirpated by whaling on the European coast before 500 A.D. and on the American coast around the late 17th to early 18th centuries.[4] However, on May 8th, 2010, a sighting of a gray whale was confirmed off the coast of Israel in the Mediterranean Sea.[5], leading some scientists to think they might be repopulating old breeding grounds that have not been used for centuries.[5] The same whale was sighted again on June 8, 2010 off the coast of Barcelona, Spain.[6]

Contents

Taxonomy

The gray whale was traditionally placed in a monotypic genus and family. Recent DNA analysis indicates that certain rorquals of the family Balaenopteridae, such as the humpback whale (Megaptera novaeangliae) and fin whale (Balaenoptera physalus) are more closely related to the gray whale than they are to some other rorquals, such as the minke whales.[7][8] John Edward Gray placed it in its own genus in 1865, naming it in honour of zoologist Daniel Eschricht.[9] The common name of the whale comes from its coloration, not from John Edward Gray's surname. It is an irony that the subfossil remains of now extinct gray whales from the Atlantic coasts of England and Sweden were used by Gray to make the first scientific description of a species then surviving only in Pacific waters. The living Pacific species was described by Cope as Ranchianectes glaucus in 1869.[10] Skeletal comparisons showed the Pacific species to be identical to the Atlantic remains in the 1930s and Gray's naming has been generally accepted since.[11][12] Although identity between the Atlantic and Pacific populations cannot be proven by anatomical data, its skeleton is distinctive and easy to distinguish from that of all other living whales.[13] Molecular analysis of Atlantic gray whale subfossil remains are needed to confirm the skeletal evidence of identity with the Pacific population.

The name Eschrichtius gibbosus is sometimes seen; this is dependent on the acceptance of a 1777 description by Erxleben.[14]

Many other names have been ascribed to the gray whale, including desert whale,[15] devil fish, gray back, mussel digger and rip sack.[16]

In the spring of 1972, a fisherman in the Laguna San Ignacio named Francisco "Pachico" Mayoral (although terrified) reached out and placed his hand in the water as a devil fish (actually a Gray mother) approached his fishing boat and gently "rubbed up against him", helping to dispel the ancient myth.[17]

Description

The gray whale is a dark slate-gray in color and covered by characteristic gray-white patterns, scars left by parasites which drop off in the cold feeding grounds. Individual whales are typically identified using photographs of their dorsal surface and matching the scars and patches associated with parasites that have fallen off the whale or are still attached.

Gray whales measure from 16 feet (4.9 m) long for newborns to 45 feet (14 m) long for adult females (which tend to be slightly larger than adult males). Newborns are a darker gray to black in color. A mature gray whale can reach 40 tonnes (39 LT; 44 ST).

They have two blowholes on top of their head, which create a distinctive V-shaped blow at the surface in calm wind conditions.

A close-up of a Gray whale's double blow hole and some of its encrusted barnacles

Notable features that distinguish the gray whale from other mysticetes include its baleen that is variously described as cream, off-white, or blond in color, and is unusually short. Small depressions on the upper jaw each contain a lone stiff hair, but are only visible on close inspection. Its head's ventral surface lacks the numerous prominent furrows of the related rorquals, instead bearing two to five shallow furrows on the throat's underside. The gray whale also lacks a dorsal fin, instead bearing several dorsal "knuckles", which are 6 to 12 raised bumps on the midline of its rear quarter, leading to the flukes. The tail itself is 10–12 feet (3.0–3.7 m) across and deeply notched at the center. Its edges taper to a point.

Populations

Two Pacific Ocean populations are known to exist: one of not more than 160 individuals whose migratory route is unknown, but presumed to be between the Sea of Okhotsk and southern Korea, and a larger one with a population between 20,000 and 22,000 individuals in the Eastern Pacific travelling between the waters off Alaska and Baja California. In 2007, S. Elizabeth Alter used a genetic approach to estimate prewhaling abundance based on samples from 42 California gray whales and reported DNA variability at 10 genetic loci consistent with a population size of 76,000–118,000 individuals, three to five times larger than today’s average census size.[18]

The gray whale became extinct in the North Atlantic in the 18th century.[19] Radiocarbon dating of subfossil or fossil European (Belgium, Netherlands, Sweden, United Kingdom) coastal remains confirms this, with whaling the likely cause.[20] Remains dating from the Roman epoch were found in the Mediterranean during excavation of the antique harbour of Lattara near Montpellier in 1997 raising the question of whether Atlantic gray whales migrated up and down the coast of Europe to calve in the Mediterranean.[21] Similarly, radiocarbon dating of American east coastal prefossil remains confirm gray whales existed at least through the 17th century. This population ranged at least from Southampton, NY to Jupiter Island, FL, the latest from 1675 AD.[12] In his 1835 history of Nantucket Island, Obed Macy wrote that in the early pre-1672 colony a whale of the kind called "scragg" entered the harbor and was pursued and killed by the settlers.[22] This event started the Nantucket whaling industry. A. B. Van Deinse points out that the "scrag whale", described by P. Dudley in 1725 as one of the species hunted by the early New England whalers, was almost certainly the Gray Whale which has flourished on the West Coast of North America with protection from whaling.[23][24]

Curiously, a gray whale was sighted off the Mediterranean shore of Israel on May 8th, 2010.[25] It has been speculated that this whale crossed from the Pacific to the Atlantic via the Northwest Passage since alternative routes through the Panama Canal or Cape Horn are not contiguous to the Pacific gray's established territory. There has been gradual melting and recession of Arctic sea ice with extreme loss in 2007 rendering the Northwest Passage "fully navigable".[26]

Life history

Reproduction

Breeding behavior is complex and often involves three or more animals. Gestation requires about one year, and females reproduce biannually. The calf is born tail first and measures about 4 meters (13 ft) in length. It is believed that the shallow lagoon waters protect the newborn from sharks.

Feeding

The whale feeds mainly on benthic crustaceans which it eats by turning on its side (usually the right, resulting in loss of eyesight in the right eye for many older animals) and scooping up sediments from the sea floor. It is classified as a baleen whale and has a baleen, or whalebone, which acts like a sieve to capture small sea animals including amphipods taken in along with sand, water and other material. Mostly, the animal feeds in the northern waters during the summer; and opportunistically feeds during its migration, depending primarily on its extensive fat reserves.

Gray whale breaching off the coast of Santa Barbara, California.
A gray whale viewed from above.

Migration

Each October as northern ice pushes southward, in the Eastern Pacific, small groups of gray whales starts a 2–3 month, 8,000–11,000 kilometres (5,000–6,800 mi) trip south. Beginning in the Bering and Chukchi seas and ending in the warm-water lagoons of Mexico's Baja peninsula and the southern Gulf of California, they travel along the west coast of Canada, the United States and Mexico. In the summer of 1980, there were three gray whale sightings in the eastern Beaufort Sea, placing them 585 585|km|mi further east than their known range at the time.[27]

Traveling night and day, the gray whale averages approximately 120 kilometers (75 mi) per day at an average speed of 8 kilometres per hour (5.0 mph). This round trip of 16,000–22,000 kilometres (9,900–14,000 mi) is believed to be the longest annual migration of any mammal. By mid-December to early January, the majority are usually found between Monterey and San Diego, often visible from shore. The whale watching industry provides ecotourists and marine mammal enthusiasts the opportunity to see groups of gray whales as they migrate.

By late December to early January, they begin to arrive in the calving lagoons of Baja. The three primary lagoons are Laguna Ojo de Libre (formerly known in English as Scammon Lagoon after whaleman Charles Scammon who discovered the lagoons in the 1850s and hunted the Grays,[28][29]), San Ignacio, and Magdalena.

These first whales to arrive are usually pregnant mothers that look for the protection of the lagoons to bear their calves, along with single females seeking mates. By mid-February to mid-March the bulk of the population has arrived in the lagoon, filling them with nursing, calving and mating gray whales.

Throughout February and March, the first to leave the lagoons are males and females without new calves. Pregnant females and nursing mothers with their newborns are the last to depart, leaving only when their calves are ready for the journey, which is usually from late March to mid-April. Often a few mothers linger with their young calves well into May.

By late March or early April, the returning animals can be seen from Everett, Washington to Puget Sound to Canada.

A population of about 2,000 gray whales stay along the Oregon coast throughout the summer, not making the farther trip to Alaska waters.

Whaling

Humans and the Orca are the adult gray whales' only predators. The Japanese began to catch gray whales beginning in the 1570s. At Kawajiri, Nagato 169 gray whales were caught between 1698 and 1889. At Tsuro, Shikoku 201 were taken between 1849 and 1896. Several hundred more were probably caught by American and European whalemen in the Sea of Okhotsk from the 1840s to the early 20th century. Whalemen caught forty-four with nets in Japan during the 1890s. The real damage was done between 1911 and 1933, when Japanese whalemen killed 1,449. By 1934 the western gray whale was near extinction. From 1891 to 1966 an estimated 1,800-2,000 gray whales were caught, with peak catches of 100-200 annually occurring in the 1910s.

Commercial whaling by Westerners in the North Pacific began in the winter of 1845-46, when two United States ships, the Hibernia and the United States, caught thirty-two in Magdalena Bay. More ships followed in the two following winters, after which gray whaling in the bay was nearly abandoned because "of the inferior quality and low price of the dark-colored gray whale oil, the low quality and quantity of whalebone from the gray, and the dangers of lagoon whaling."

Gray whaling in Magdalena Bay was revived in the winter of 1855-56 by several vessels, mainly from San Francisco, including the ship Leonore, under Captain Charles Melville Scammon. This was the first of eleven winters from 1855 through 1865 known as the "bonanza period," during which gray whaling along the coast of Baja California reached its peak. Not only were Grays taken in Magdalena Bay, but also by ships anchored along the coast from San Diego south to Cabo San Lucas and from whaling stations from Crescent City in northern California south to San Ignacio Lagoon. During the same period vessels targeting right and bowhead whales in the Gulf of Alaska, Sea of Okhotsk, and the Western Arctic would occasionally take a Gray or two if neither of the more desirable two species were in sight.

In December 1857 Charles Scammon, in the brig Boston, along with his schooner-tender Marin, entered Laguna Ojo de Liebre (Jack-Rabbit Spring Lagoon) or later known as Scammon's Lagoon (by 1860) and found one the gray's last refuges. In three months he caught forty-seven, yielding 1,700 barrels of oil. In the winter of 1859-60, Scammon, in the bark Ocean Bird, along with several other vessels, performed a similar feat of daring by entering San Ignacio Lagoon to the south where he discovered the last breeding lagoon. Within only a couple of seasons the lagoon was nearly devoid of whales.

Between 1846 and 1874 an estimated 8,000 gray whales were killed by American and European whalemen, with over half having been killed in the Magdalena Bay complex (Estero Santo Domingo, Magdalena Bay itself, and Almejas Bay) and by shore whalemen in California and Baja California. This, for the most part, does not take into account the large number of calves injured or left to starve after their mothers had been killed in the breeding lagoons. Since whalemen primarily targeted these new mothers, several thousand deaths should probably be added to the total. Shore whaling in California and Baja California continued after this period, until the early 20th century.

A second, shorter, and less intensive hunt occurred for gray whales in the eastern North Pacific. Only a few were caught from two whaling stations on the coast of California from 1919 to 1926, and a single station in Washington (1911–21) accounted for the capture of another. For the entire west coast of North America for the years 1919 to 1929 some 234 gray whales were caught. Only a dozen or so were taken by British Columbian stations, nearly all of them in 1953 at Coal Harbor. A whaling station in Richmond, California caught 311 gray whales for "scientific purposes" between 1964 and 1969. From 1961 to 1972 the Soviet Union caught 138 gray whales (they originally reported not having taken any.) The only other significant catch was made in two seasons by the steam-schooner California off Malibu, California. In the winters of 1934-35 and 1935-36 the California anchored off Point Dume in Paradise Cove. In all she caught at least 272 gray whales, 186 in the first winter. In 1936 gray whales became protected.

As of 2001, the California gray whale population had grown to about 26,000. As of 2004, the population of Western Pacific (seas near Korea, Japan, and Kamchatka) gray whales was an estimated 101.

The North Atlantic population may have been hunted to extinction in the 18th century. There is circumstantial evidence that whaling could have contributed to this population's decline, as the increase in whaling activity in the 17th and 18th century coincided with the population's disappearance.[12] A. B. Van Deinse points out that the "scrag whale", described by P. Dudley in 1725 as one target of early New England whalers, was almost certainly the gray whale.[30][31] In his 1835 history of Nantucket Island, Obed Macy wrote that in the early pre-1672 colony a whale of the kind called "scragg" entered the harbor and was pursued and killed by the settlers.[32] This event started the Nantucket whaling industry.

Gray Whale Skeleton articulated by Skulls Unlimited International.

Conservation

Gray whales have been granted protection from commercial hunting by the International Whaling Commission (IWC) since 1949, and are no longer hunted on a large scale.

Limited hunting of gray whales has continued since that time, however, primarily in the Chukotka region of northeastern Russia, where large numbers of gray whales spend the summer months. This hunt has been allowed under an "aboriginal/subsistence whaling" exception to the commercial-hunting ban. Anti-whaling groups have protested the hunt, saying that the meat from the whales is not for traditional native consumption, but is used instead to feed animals in government-run fur farms; they cite annual catch numbers that rose dramatically during the 1940s, at the time when state-run fur farms were being established in the region. Although the Soviet government denied these charges as recently as 1987, in recent years the Russian government has acknowledged this practice. The Russian IWC delegation has said that the hunt is justified under the aboriginal/subsistence exemption, since the fur farms provide a necessary economic base for the region's native population.

Currently, the annual quota for the gray whale catch in the region is 140 per year. Pursuant to an agreement between the United States and Russia, the Makah tribe of Washington claimed 4 whales from the IWC quota established at the 1997 meeting. With the exception of a single gray whale killed in 1999, the Makah people have been prevented from hunting by a series of legal challenges, culminating in a United States federal appeals court decision in December 2002 that required the National Marine Fisheries Service to prepare an Environmental Impact Statement. On September 8, 2007, five members of the Makah tribe shot a gray whale using high powered rifles in spite of the decision. The whale died within 12 hours, sinking while heading out to sea.[33]

Today the law protects whales in all three lagoons, but whale watching is permitted.

As of 2008, the IUCN regards the gray whale as being of "Least Concern" from a conservation perspective. However, the specific subpopulation in the northwest Pacific is regarded as being "Critically Endangered".[2] The northwest Pacific population is also listed as endangered by the U.S. Government National Marine Fisheries Service under the U.S. Endangered Species Act.

Captivity

In 1972, a 3-month-old gray whale named Gigi was captured for brief study by Dr. David W. Kenney, and then released near San Diego.

In January 1997, the new-born baby whale J.J. was found helpless near the coast of Los Angeles, California, 4.2 meters (14 ft) long and 800 kilograms (1,764 lb) in weight. Nursed back to health in SeaWorld San Diego, she was released into the Pacific Ocean on March 31, 1998, 9 meters (30 ft) long and 8,500 kilograms (18,739 lb) in mass. She shed her radio transmitter packs three days later.

References

  1. ↑ Mead, James G.; Brownell, Robert L., Jr. (16 November 2005). "Order Cetacea (pp. 723-743)". In Wilson, Don E., and Reeder, DeeAnn M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=14300030. 
  2. ↑ 2.0 2.1 Reilly SB, Bannister JL, Best PB, Brown M, Brownell Jr. RL, Butterworth DS, Clapham PJ, Cooke J, Donovan GP, Urbán J & Zerbini AN (2008). Eschrichtius robustus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 2008-10-17.
  3. ↑ American Cetacean Society Fact Sheet on Gray Whale
  4. ↑ William F. Perrin, Bernd G. Würsig, J. G. M. Thewissen (2009). [Encyclopedia of marine mammals By William F. Perrin, Bernd G. Würsig, J. G. M. Thewissen Encyclopedia of marine mammals]. Academic Press. p. 404. ISBN 9780123735539. Encyclopedia of marine mammals By William F. Perrin, Bernd G. Würsig, J. G. M. Thewissen. Retrieved 2010-07-15. 
  5. ↑ 5.0 5.1 Thomas, Pete (10 May 2010). "’Gray whale off Israel called 'most amazing sighting in history of whales'‘". GrindTV.com. http://www.grindtv.com/outdoor/blog/17453/gray+whale+off+israel+called+most+amazing+sighting+in+history+of+whales. Retrieved 12 May 2010. 
  6. ↑ "’Mystery gray whale sighted again off Spain coast‘". BBC News. 30 May 2010. http://news.bbc.co.uk/earth/hi/earth_news/newsid_8729000/8729064.stm. Retrieved 08 June 2010. 
  7. ↑ Arnason, U., Gullberg A. & Widegren, B. (1 September 1993). "Cetacean mitochondrial DNA control region: sequences of all extant baleen whales and two sperm whale species". Molecular Biology and Evolution 10 (5): 960–970. PMID 8412655. http://mbe.oxfordjournals.org/cgi/content/abstract/10/5/960. Retrieved 2009-01-25. 
  8. ↑ Sasaki, T. et al. (February 23, 2005). "Mitochondrial Phylogenetics and Evolution of Mysticete Whales". Systematic Biology 54 (1): 77–90. doi:10.1080/10635150590905939. PMID 15805012. http://www.informaworld.com/smpp/content~content=a716097098~db=all. Retrieved 2009-01-25. 
  9. ↑ Gray (1864). "Eschrichtius". Ann. Mag. Nat. Hist. 3 (14): 350. 
  10. ↑ Cope (1869). "Rhachianectes". Proc. Acad. Nat. Sci. Philadelphia 21: 15. 
  11. ↑ Cederlund, BA (1938). "A subfossil gray whale discovered in Sweden in 1859". Zoologiska Bidrag Fran Uppsala 18: 269–286. 
  12. ↑ 12.0 12.1 12.2 Mead JG, Mitchell ED (1984). "Atlantic gray whales". In Jones ML, Swartz SL, Leatherwood S. The Gray Whale. London: Academic Press. pp. 33–53. 
  13. ↑ Bryant, PJ (1995). "Dating Remains of Gray Whales from the Eastern North Atlantic". Journal of Mammalogy 76 (3): 857–861. doi:10.2307/1382754. 
  14. ↑ Erxleben (1777). "Balaena gibbosa". Systema regni animalis: 610. 
  15. ↑ Katherine Waser Ecotourism and the desert whale: An interview with Dr. Emily Young (1998). Arid Lands Newsletter. 
  16. ↑ "Eschrichtius robustus". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=180521. Retrieved March 18, 2006. 
  17. ↑ Russell,Dick (2004). Eye of the Whale: Epic Passage From Baja To Siberia. Island Press. pp. 48–49. ISBN 1559630884. http://books.google.com/books?id=BHfP7D1w8vYC&dq=eye+of+the+whale+russell&printsec=frontcover&source=bl&ots=x-3u1KGt1C&sig=J_gmTngeDs4R6S9ewkZIP7OvZGg&hl=en&ei=B2fAStnvK4bUtgOunrk-&sa=X&oi=book_result&ct=result&resnum=1#v=onepage&q=pachico&f=false. 
  18. ↑ Alter, SE; Rynes, E.; Palumbi, S. R. (September 2007). "DNA evidence for historic population size and past ecosystem impacts of gray whales". Proceedings of the National Academy of Sciences 104 (38): 15162–15167. doi:10.1073/pnas.0706056104. 
  19. ↑ Rice DW (1998). Marine Mammals of the World. Systematics and Distribution. Special Publication Number 4.. Lawrence, Kansas: The Society for Marine Mamalogy. 
  20. ↑ Bryant, PJ (August 1995). "Dating Remains of Gray Whales from the Eastern North Atlantic". Journal of Mammalogy 76 (3): 857–861. doi:10.2307/1382754. 
  21. ↑ Macé M. (2003). "Did the Gray Whale calve in the Mediterranean ?". Lattara 16: 153-164. http://www.archive.org/details/DidTheGrayWhaleEschrichtiusRobustusCalveInTheMediterranean. 
  22. ↑ Macy O (1835). The History of Nantucket:being a compendious account of the first settlement of the island by the English:together with the rise and progress of the whale fishery, and other historical facts relative to said island and its inhabitants:in two parts. Boston: Hilliard, Gray & Co.. ISBN 1437402232. 
  23. ↑ Van Deinse, AB (1937). "Recent and older finds of the gray whale in the Atlantic". Temminckia 2: 161–188. 
  24. ↑ Dudley, P (1725). "An essay upon the natural history of whales". Philosophical Transactions of the Royal Society of London 33: 256–259. 
  25. ↑ http://www.haaretz.co.il/hasite/spages/1167822.html
  26. ↑ "Satellites witness lowest Arctic ice coverage in history". http://www.esa.int/esaCP/SEMYTC13J6F_index_0.html. Retrieved 2007-09-14. 
  27. ↑ David J. Rugh and Mark A. Fraker (June, 1981). "Gray Whale (Eschrichtius robustus) Sightings in Eastern Beaufort Sea". Arctic. http://pubs.aina.ucalgary.ca/arctic/Arctic34-2-186.pdf. Retrieved 2010-07-15. 
  28. ↑ Davis, T.N. (September 6, 1979). "Recovery of the Gray Whale". Alaska Science Forum. http://www.gi.alaska.edu/ScienceForum/ASF3/339.html. Retrieved 2009-01-25. 
  29. ↑ Niemann, G. (2002). Baja Legends. Sunbelt Publications. pp. 171–173. ISBN 0932653472. http://books.google.com/books?id=35WQOduN1F4C&pg=PA171&lpg=PA171&dq=charles+scammon+gray+whale&source=web&ots=EKUwNIZAea&sig=ib5YxqKv-PqqcONQW_OZ5W7MYOQ&hl=en&sa=X&oi=book_result&resnum=3&ct=result#PPA173,M1. 
  30. ↑ Van Deinse, AB (1937). "Recent and older finds of the gray whale in the Atlantic". Temminckia 2: 161–188. 
  31. ↑ Dudley, P (1725). "An essay upon the natural history of whales". Philosophical Transactions of the Royal Society of London 33: 256–259. 
  32. ↑ Macy O (1835). The History of Nantucket:being a compendious account of the first settlement of the island by the English:together with the rise and progress of the whale fishery, and other historical facts relative to said island and its inhabitants:in two parts. Boston: Hilliard, Gray & Co.. ISBN 1437402232. 
  33. ↑ Mapes, Lynda V.; Ervin, Keith (2007-09-09). "Gray whale shot, killed in rogue tribal hunt". The Seattle Times. http://seattletimes.nwsource.com/html/localnews/2003876011_whale09m.html. 

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