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129-527: This bay is particularly noted for the seasonal migration of the California gray whales that come here during winter to calve. The bay is also popular for commercial and sports fishing . Nearby mangrove swamps provide sanctuaries for sea birds. The bay includes the small fishing port of San Carlos , as well as Puerto López Mateos , which provides a good place to observe the whales. Sandy barrier islands Isla Magdalena and Isla Santa Margarita separate

258-492: A World Heritage Site for their geological value, four of them are considered of "Outstanding Universal Value" based on their cultural and natural criteria: Þingvellir , Iceland; Landscape of the Pico Island Vineyard Culture , Portugal; Gough and Inaccessible Islands , United Kingdom; and Brazilian Atlantic Islands: Fernando de Noronha and Atol das Rocas Reserves, Brazil. Continental shelves in

387-506: A Navy Sonic Depth Finder to draw a continuous map across the bed of the Atlantic. This involved little guesswork because the idea of sonar is straightforward with pulses being sent from the vessel, which bounce off the ocean floor, then return to the vessel. The deep ocean floor is thought to be fairly flat with occasional deeps, abyssal plains , trenches , seamounts , basins , plateaus , canyons , and some guyots . Various shelves along

516-721: A branch of the Gulf Stream which flows northward from the Grand Banks ; and the Subpolar Front , an extension of the North Atlantic Current, a wide, vaguely defined region separating the subtropical gyre from the subpolar gyre. This system of currents transports warm water into the North Atlantic, without which temperatures in the North Atlantic and Europe would plunge dramatically. North of

645-412: A darker gray to black in color. A mature gray whale can reach 40 t (44 short tons), with a typical range of 15–33 t (17–36 short tons), making them the ninth largest sized species of cetacean. 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

774-429: A few French , Dutch , and Russian , whaleships hunted gray whales in the bay during their winter calving season. They primarily caught cows and calves, but began catching bulls as the former became scarce. During the peak years from the winters of 1855–56 to 1864–65, an estimated 1,250 gray whales were caught in the bay, with a peak of about 250 whales taken by seventeen vessels in the winter of 1856–57. They also visited

903-457: A few mothers linger with their young calves well into May. Whale watching in Baja's lagoons is particularly popular because the whales often come close enough to boats for tourists to pet them. By late March or early April, the returning animals can be seen from Puget Sound to Canada. A population of about 200 gray whales stay along the eastern Pacific coast from Canada to California throughout

1032-494: A gray whale 30 miles (48 km) south of Nantucket, Massachusetts . Researchers used a genetic approach to estimate pre-whaling abundance based on samples from 42 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 the average census size as measured through 2007. The National Oceanic and Atmospheric Administration has collected surveys of gray whale population since at least

1161-665: A gray whale was sighted off Sunny Isles Beach, Florida . Genetic analysis of fossil and prefossil gray whale remains in the Atlantic Ocean suggests several waves of dispersal from the Pacific to the Atlantic related to successive periods of climactic warming – during the Pleistocene before the last glacial period and the early Holocene immediately following the opening of the Bering Strait . This information and

1290-614: A group of two or three were observed feeding in Izu Ōshima in 1994 for almost a month, two single individuals stayed in Ise Bay for almost two months in the 1980s and in 2012, the first confirmed living individuals in Japanese EEZ in the Sea of Japan and the first of living cow-calf pairs since the end of whaling stayed for about three weeks on the coastline of Teradomari in 2014. One of

1419-479: A handful of capture records support this idea, although migrations into the sea have been confirmed. Recent studies using genetics and acoustics, suggest that there are several wintering sites for western gray whales such as Mexico and the East China sea. However, their wintering ground habits in the western North Pacific are still poorly understood and additional research is needed. Even though South Korea put

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1548-655: A historically unique event. That study suggested that over the past 100,000 years there have been several migrations of gray whales between the Pacific and Atlantic, with the most recent large scale migration of this sort occurring about 5,000 years ago. These migrations corresponded to times of relatively high temperatures in the Arctic Ocean. In 2021, one individual was seen in the port of Rabat , Morocco , followed by sightings in Algeria and Italy . In March 2024, New England Aquarium researchers photographed

1677-589: A member of the family Balaenopteridae . This mammal is descended from filter-feeding whales that appeared during the Neogene . The gray whale is distributed in a Northeast Pacific (North American), and an endangered Northwest Pacific (Asian), population. North Atlantic populations were extirpated (perhaps by whaling ) on the European coast before 500 CE , and on the American and African Atlantic coasts around

1806-584: A prey of choice, gray whales are opportunistic feeders and can easily switch from feeding planktonically to benthically. When gray whales feed planktonically, they roll onto their right side while their fluke remains above the surface, or they apply the skimming method seen in other baleen whales (skimming the surface with their mouth open). This skimming behavior mainly seems to be used when gray whales are feeding on crab larvae. Other prey items include polychaete worms , herring eggs, various forms of larvae, and small fish. Gray whales feed benthically, by diving to

1935-429: A subfossil found in the brackish Baltic Sea , apparently a specimen from the now extinct north Atlantic population. Lilljeborg, however, identified it as " Balaenoptera robusta ", a species of rorqual . Gray 1864 realized that the rib and scapula of the specimen was different from those of any known rorquals, and therefore erected a new genus for it, Eschrichtius . Van Beneden & Gervais 1868 were convinced that

2064-416: A weak Intertropical Convergence Zone , South Atlantic tropical cyclones are rare. The Atlantic Ocean is underlain mostly by dense mafic oceanic crust made up of basalt and gabbro and overlain by fine clay, silt and siliceous ooze on the abyssal plain. The continental margins and continental shelf mark lower density, but greater thickness felsic continental rock that is often much older than that of

2193-462: Is Puerto Cortés , the only settlement on the island, the site of a naval base administered from the 2nd Military Naval Region in Ensenada , Baja California . It has a military-only airstrip and no official registered population. As early as 1837 American whaleships visited the bay to cooper their oil and hunt sperm whales outside the bay. Between 1845–46 and 1865–66, American, as well as

2322-621: Is a complex of four water masses, two that form by deep convection in the open ocean – classical and upper Labrador sea water – and two that form from the inflow of dense water across the Greenland-Iceland-Scotland sill – Denmark Strait and Iceland-Scotland overflow water. Along its path across Earth the composition of the NADW is affected by other water masses, especially Antarctic bottom water and Mediterranean overflow water. The NADW

2451-626: Is approximately 13  1 ⁄ 2 months, with females giving birth every one to three years. In the latter half of the pregnancy, the fetus experiences a rapid growth in length and mass. Similar to the narrow breeding season, most calves are born within a six-week time period in mid January. The calf is born tail first, and measures about 14–16 ft in length, and a weight of 2,000 lbs. Females lactate for approximately seven months following birth, at which point calves are weaned and maternal care begins to decrease. The shallow lagoon waters in which gray whales reproduce are believed to protect

2580-432: 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 such as at Morro bay , 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, eastern grays begin to arrive in

2709-419: Is distinctive and easy to distinguish from that of all other living whales. Many other names have been ascribed to the gray whale, including desert whale, devilfish, gray back, mussel digger and rip sack. The name Eschrichtius gibbosus is sometimes seen; this is dependent on the acceptance of a 1777 description by Erxleben. A number of 18th century authors described the gray whale as Balaena gibbosa ,

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2838-467: Is fed by a flow of warm shallow water into the northern North Atlantic which is responsible for the anomalous warm climate in Europe. Changes in the formation of NADW have been linked to global climate changes in the past. Since human-made substances were introduced into the environment, the path of the NADW can be traced throughout its course by measuring tritium and radiocarbon from nuclear weapon tests in

2967-498: Is found off the eastern coast of Canada. Surface water temperatures, which vary with latitude, current systems, and season and reflect the latitudinal distribution of solar energy, range from below −2 °C (28 °F) to over 30 °C (86 °F). Maximum temperatures occur north of the equator, and minimum values are found in the polar regions. In the middle latitudes, the area of maximum temperature variations, values may vary by 7–8 °C (13–14 °F). From October to June

3096-575: Is interrupted by larger transform faults at two places: the Romanche Trench near the Equator and the Gibbs fracture zone at 53°N . The MAR is a barrier for bottom water, but at these two transform faults deep water currents can pass from one side to the other. The MAR rises 2–3 km (1.2–1.9 mi) above the surrounding ocean floor and its rift valley is the divergent boundary between

3225-854: Is intersected by two perpendicular ridges: the Azores–Gibraltar Transform Fault , the boundary between the Nubian and Eurasian plates , intersects the MAR at the Azores triple junction , on either side of the Azores microplate, near the 40°N . A much vaguer, nameless boundary, between the North American and South American plates, intersects the MAR near or just north of the Fifteen-Twenty fracture zone , approximately at 16°N . In

3354-729: Is now northern and central Brazil. The formation of the Central American Isthmus closed the Central American Seaway at the end of the Pliocene 2.8 Ma ago. The formation of the isthmus resulted in the migration and extinction of many land-living animals, known as the Great American Interchange , but the closure of the seaway resulted in a "Great American Schism" as it affected ocean currents, salinity, and temperatures in both

3483-794: Is now the Carpathian region, that were similar to the Sargasso Sea. It is possible that the population in the Sargasso Sea migrated to the Atlantic as the Tethys closed at the end of the Miocene around 17 Ma. The origin of the Sargasso fauna and flora remained enigmatic for centuries. The fossils found in the Carpathians in the mid-20th century often called the "quasi-Sargasso assemblage", finally showed that this assemblage originated in

3612-622: Is only one confirmed record of accidentally killing of the species in Vietnam, at Ngoc Vung Island off Ha Long Bay in 1994 and the skeleton is on exhibition at the Quang Ninh Provincial Historical Museum. Gray whales are known to occur in Taiwan Strait even in recent years. It is also unknown whether any winter breeding grounds ever existed beyond Chinese coasts. For example, it is not known if

3741-592: Is the shallow (5–15 m (16–49 ft) depth) shelf off northeastern Sakhalin Island , particularly off the southern portion of Piltun Lagoon, where the main prey species appear to be amphipods and isopods . In some years, the whales have also used an offshore feeding ground in 30–35 m (98–115 ft) depth southeast of Chayvo Bay, where benthic amphipods and cumaceans are the main prey species. Some gray whales have also been seen off western Kamchatka, but to date all whales photographed there are also known from

3870-520: The Age of Discovery , the Atlantic was also known to English cartographers as the Great Western Ocean . The pond is a term often used by British and American speakers in reference to the northern Atlantic Ocean, as a form of meiosis , or ironic understatement. It is used mostly when referring to events or circumstances "on this side of the pond" or "on the other side of the pond" or "across

3999-513: The Akishima whale ( E. akishimaensis ). Some recent studies place gray whales as being outside the rorqual clade , but as the closest relatives to the rorquals. But other recent DNA analyses have suggested 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

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4128-678: The Americas ( North America and South America ) from the Old World of Afro-Eurasia ( Africa , Asia , and Europe ). Through its separation of Afro-Eurasia from the Americas, the Atlantic Ocean has played a central role in the development of human society, globalization, and the histories of many nations. While the Norse were the first known humans to cross the Atlantic, it was the expedition of Christopher Columbus in 1492 that proved to be

4257-550: The Bering and Chukchi seas and ending in the warm-water lagoons of Mexico's Baja California Peninsula and the southern Gulf of California , they travel along the west coast of Canada, the United States and Mexico. Traveling night and day, the gray whale averages approximately 120 km (75 mi) per day at an average speed of 8 km/h (5 mph). This round trip of 16,000–22,000 km (9,900–13,700 mi)

4386-564: The Carpathian Basin from where it migrated over Sicily to the central Atlantic where it evolved into modern species of the Sargasso Sea. The location of the spawning ground for European eels remained unknown for decades . In the early 19th century it was discovered that the southern Sargasso Sea is the spawning ground for both the European and American eel and that the former migrate more than 5,000 km (3,100 mi) and

4515-474: The Icelandic Low produces frequent storms. Icebergs are common from early February to the end of July across the shipping lanes near the Grand Banks of Newfoundland . The ice season is longer in the polar regions, but there is little shipping in those areas. Hurricanes are a hazard in the western parts of the North Atlantic during the summer and autumn. Due to a consistently strong wind shear and

4644-569: The Islas Marías , Bahía de Banderas , and Nayarit / Jalisco , and there were two modern calving grounds in Sonora ( Tojahui or Yavaros ) and Sinaloa ( Bahia Santa Maria , Bahia Navachiste, La Reforma, Bahia Altata) until being abandoned in the 1980s. These first whales to arrive are usually pregnant mothers looking for the protection of the lagoons to bear their calves, along with single females seeking mates. By mid-February to mid-March,

4773-684: The North American and Eurasian plates in the North Atlantic and the South American and African plates in the South Atlantic. The MAR produces basaltic volcanoes in Eyjafjallajökull , Iceland, and pillow lava on the ocean floor. The depth of water at the apex of the ridge is less than 2,700 m (1,500 fathoms ; 8,900  ft ) in most places, while the bottom of the ridge is three times as deep. The MAR

4902-616: The North Atlantic Drift is thought to have at least some influence on climate. For example, the Gulf Stream helps moderate winter temperatures along the coastline of southeastern North America, keeping it warmer in winter along the coast than inland areas. The Gulf Stream also keeps extreme temperatures from occurring on the Florida Peninsula. In the higher latitudes, the North Atlantic Drift, warms

5031-514: The North Atlantic oscillation , occurs. On average, the Atlantic is the saltiest major ocean; surface water salinity in the open ocean ranges from 33 to 37 parts per thousand (3.3–3.7%) by mass and varies with latitude and season. Evaporation, precipitation, river inflow and sea ice melting influence surface salinity values. Although the lowest salinity values are just north of the equator (because of heavy tropical rainfall), in general,

5160-500: The Scotia Sea , and other tributary water bodies. Including these marginal seas the coast line of the Atlantic measures 111,866 km (69,510 mi) compared to 135,663 km (84,297 mi) for the Pacific. Including its marginal seas, the Atlantic covers an area of 106,460,000 km (41,100,000 sq mi) or 23.5% of the global ocean and has a volume of 310,410,900 km (74,471,500 cu mi) or 23.3% of

5289-447: The Sea of Okhotsk , mainly off Piltun Bay region at the northeastern coast of Sakhalin Island (Russian Federation). There are also occasional sightings off the eastern coast of Kamchatka (Russian Federation) and in other coastal waters of the northern Okhotsk Sea. Its migration routes and wintering grounds are poorly known, the only recent information being from occasional records on both

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5418-1147: The Shakotan Peninsula , and islands in the La Pérouse Strait such as Rebun Island and Rishiri Island . These areas may also have included feeding grounds. There are shallow, muddy areas favorable for feeding whales off Shiretoko , such as at Shibetsu , the Notsuke Peninsula , Cape Ochiishi on Nemuro Peninsula , Mutsu Bay , along the Tottori Sand Dunes , in the Suou-nada Sea , and Ōmura Bay . The historical calving grounds were unknown but might have been along southern Chinese coasts from Zhejiang and Fujian Province to Guangdong , especially south of Hailing Island and to near Hong Kong . Possibilities include Daya Bay , Wailou Harbour on Leizhou Peninsula , and possibly as far south as Hainan Province and Guangxi , particularly around Hainan Island . These areas are at

5547-619: The Titan in Greek mythology , who supported the heavens and who later appeared as a frontispiece in medieval maps and also lent his name to modern atlases . On the other hand, to early Greek sailors and in ancient Greek mythological literature such as the Iliad and the Odyssey , this all-encompassing ocean was instead known as Oceanus , the gigantic river that encircled the world; in contrast to

5676-534: The flukes . This is known as the dorsal ridge . The tail itself is 3–3.5 m (10–11 ft) across and deeply notched at the center while its edges taper to a point. The two populations of Pacific gray whales (east and west) are morphologically and phylogenically different. Other than DNA structures, differences in proportions of several body parts and body colors including skeletal features, and length ratios of flippers and baleen plates have been confirmed between Eastern and Western populations, and some claims that

5805-638: The meridional overturning circulation (MOC), the northward heat transport of which is threatened by anthropogenic climate change. Large variations in the subpolar gyre on a decade-century scale, associated with the North Atlantic oscillation , are especially pronounced in Labrador Sea Water , the upper layers of the MOC. The South Atlantic is dominated by the anti-cyclonic southern subtropical gyre. The South Atlantic Central Water originates in this gyre, while Antarctic Intermediate Water originates in

5934-409: The minke whales . The American Society of Mammalogists has followed this classification. John Edward Gray placed it in its own genus in 1865, naming it in honour of physician and zoologist Daniel Frederik Eschricht . The common name of the whale comes from its coloration. The subfossil remains of now extinct gray whales from the Atlantic coasts of England and Sweden were used by Gray to make

6063-458: The thermocline of the subtropical gyre. The Sargasso Sea in the western North Atlantic can be defined as the area where two species of Sargassum ( S. fluitans and natans ) float, an area 4,000 km (2,500 mi) wide and encircled by the Gulf Stream , North Atlantic Drift , and North Equatorial Current . This population of seaweed probably originated from Tertiary ancestors on

6192-659: The "whale with six bosses", apparently based on a brief note by Dudley 1725 : The Scrag Whale is near a kin to the Fin-back, but instead of a Fin upon his Back, the Ridge of the Afterpart of his Back is cragged with half a Dozen Knobs or Nuckles; he is nearest the right Whale in Figure and for Quantity of Oil; his Bone is white, but won't split. The gray whale was first described as a distinct species by Lilljeborg 1861 based on

6321-418: The 17th century. This population ranged at least from Southampton, New York , to Jupiter Island, Florida , the latest from 1675. 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. A. B. Van Deinse points out that the "scrag whale", described by P. Dudley in 1725 as one of

6450-578: The 1870s, the Challenger expedition discovered parts of what is now known as the Mid-Atlantic Ridge, or: An elevated ridge rising to an average height of about 1,900 fathoms [3,500 m; 11,400 ft] below the surface traverses the basins of the North and South Atlantic in a meridianal direction from Cape Farewell, probably its far south at least as Gough Island, following roughly

6579-466: The 1930s when it was finally realised that the extinct Atlantic population was the same species as the extant Pacific population, and the new combination Eschrichtius gibbosus was proposed. The gray whale has a dark slate-gray color and is covered by characteristic gray-white patterns, which are scars left by parasites that drop off in its cold feeding grounds. Individual whales are typically identified using photographs of their dorsal surface, matching

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6708-618: The 1953 definition it extends south to Antarctica, while in later maps it is bounded at the 60° parallel by the Southern Ocean. The Atlantic has irregular coasts indented by numerous bays, gulfs and seas. These include the Baltic Sea , Black Sea , Caribbean Sea , Davis Strait , Denmark Strait , part of the Drake Passage , Gulf of Mexico , Labrador Sea , Mediterranean Sea , North Sea , Norwegian Sea , almost all of

6837-485: The 1960s and CFCs . The clockwise warm-water North Atlantic Gyre occupies the northern Atlantic, and the counter-clockwise warm-water South Atlantic Gyre appears in the southern Atlantic. In the North Atlantic, surface circulation is dominated by three inter-connected currents: the Gulf Stream which flows north-east from the North American coast at Cape Hatteras ; the North Atlantic Current ,

6966-785: The 1960s. They state that "the most recent population estimate [from 2007] was approximately 19,000 whales, with a high probability (88%) that the population is at 'optimum sustainable population' size, as defined by the Marine Mammal Protection Act ." They speculate that the ocean ecosystem has likely changed since the prewhaling era, making a return to prewhaling numbers infeasible. Factors limiting or threatening current population levels include ship strikes, entanglement in fishing gear, and changes in sea-ice coverage associated with climate change. Several whales seen off Sakhalin and on Kamchatka Peninsula have been confirmed to migrate towards eastern side of Pacific and join

7095-537: The Atlantic are wide off Newfoundland, southernmost South America, and northeastern Europe. In the western Atlantic carbonate platforms dominate large areas, for example, the Blake Plateau and Bermuda Rise . The Atlantic is surrounded by passive margins except at a few locations where active margins form deep trenches : the Puerto Rico Trench (8,376 m or 27,480 ft maximum depth) in

7224-468: The Atlantic include the Challenger expedition and the German Meteor expedition ; as of 2001 , Columbia University 's Lamont–Doherty Earth Observatory and the United States Navy Hydrographic Office conduct research on the ocean. The MAR divides the Atlantic longitudinally into two halves, in each of which a series of basins are delimited by secondary, transverse ridges. The MAR reaches above 2,000 m (6,600 ft) along most of its length, but

7353-403: The Atlantic north of the equator. The coldest zones are in high latitudes, with the coldest regions corresponding to the areas covered by sea ice. Ocean currents influence the climate by transporting warm and cold waters to other regions. The winds that are cooled or warmed when blowing over these currents influence adjacent land areas. The Gulf Stream and its northern extension towards Europe,

7482-408: The Atlantic sea ' , etym . ' Sea of Atlas ' ) and in The Histories of Herodotus around 450 BC (Hdt. 1.202.4): Atlantis thalassa (Ancient Greek: Ἀτλαντὶς θάλασσα , ' Sea of Atlas ' or ' the Atlantic sea ' ) where the name refers to "the sea beyond the pillars of Heracles " which is said to be part of the sea that surrounds all land. In these uses, the name refers to Atlas ,

7611-409: The Bahamas, while coarse river outwash sands and silt are common in shallow shelf areas like the Georges Bank . Coarse sand, boulders, and rocks were transported into some areas, such as off the coast of Nova Scotia or the Gulf of Maine during the Pleistocene ice ages. The break-up of Pangaea began in the central Atlantic, between North America and Northwest Africa, where rift basins opened during

7740-402: The DNA analysis of last recorded stranding in China. Differences were also observed between Korean and Chinese specimens. Two Pacific Ocean populations are known to exist: one population that is very low, whose migratory route is presumed to be between the Sea of Okhotsk and southern Korea, and a larger one with a population of about 27,000 individuals in the eastern Pacific traveling between

7869-404: The European shores of the former Tethys Ocean and has, if so, maintained itself by vegetative growth , floating in the ocean for millions of years. Other species endemic to the Sargasso Sea include the sargassum fish , a predator with algae-like appendages which hovers motionless among the Sargassum . Fossils of similar fishes have been found in fossil bays of the former Tethys Ocean, in what

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7998-460: The IUCN downlisted the population's conservation status from critically endangered to endangered . The gray whale became extinct in the North Atlantic in the 18th century. They had been seasonal migrants to coastal waters of both sides of Atlantic, including the Baltic Sea , the Wadden Sea , the Gulf of St. Lawrence , the Bay of Fundy , Pamlico Sound and possibly Hudson Bay . Radiocarbon dating of subfossil or fossil European (Belgium,

8127-440: The Japanese Emperor as attempting to utilize this bay and perhaps Whale Bay for military naval purposes. Gray whale The gray whale ( Eschrichtius robustus ), also known as the grey whale , is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of 14.9 meters (49 ft), a weight of up to 41 tonnes (90,000 lb) and lives between 55 and 70 years, although one female

8256-405: The Late Triassic and Early Jurassic. This period also saw the first stages of the uplift of the Atlas Mountains. The exact timing is controversial with estimates ranging from 200 to 170 Ma. The opening of the Atlantic Ocean coincided with the initial break-up of the supercontinent Pangaea , both of which were initiated by the eruption of the Central Atlantic Magmatic Province (CAMP), one of

8385-400: The Netherlands, Sweden, the United Kingdom) coastal remains confirms this, with whaling the possible cause for the population's extinction. Remains dating from the Roman epoch were found in the Mediterranean during excavation of the antique harbor of Lattara near Montpellier , France, in 1997, raising the question of whether Atlantic gray whales migrated up and down the coast of Europe from

8514-468: The North Atlantic Gyre, the cyclonic North Atlantic Subpolar Gyre plays a key role in climate variability. It is governed by ocean currents from marginal seas and regional topography, rather than being steered by wind, both in the deep ocean and at sea level. The subpolar gyre forms an important part of the global thermohaline circulation . Its eastern portion includes eddying branches of the North Atlantic Current which transport warm, saline waters from

8643-399: The Piltun area. Diagram of the gray whale seafloor feeding strategy Predicted distribution models indicate that overall range in the last glacial period was broader or more southerly distributed, and inhabitations in waters where species presences lack in present situation, such as in southern hemisphere and south Asian waters and northern Indian Ocean were possible due to feasibility of

8772-437: The South Atlantic, and the "Atmospheric Bridge", which evaporates subtropical Atlantic waters and exports it to the Pacific. The Atlantic Ocean consists of four major, upper water masses with distinct temperature and salinity. The Atlantic subarctic upper water in the northernmost North Atlantic is the source for subarctic intermediate water and North Atlantic intermediate water. North Atlantic central water can be divided into

8901-404: The United States and Brazil , both increased in degree during the early 20th century, and while no major military conflicts have taken place in the Atlantic recently, the ocean remains a core component of trade around the world. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and the Americas to the west. As one component of

9030-454: The Wadden Sea to calve in the Mediterranean. A 2018 study utilizing ancient DNA barcoding and collagen peptide matrix fingerprinting confirmed that Roman era whale bones east of the Strait of Gibraltar were gray whales (and North Atlantic right whales ), confirming that gray whales once ranged into the Mediterranean. Similarly, radiocarbon dating of American east coastal subfossil remains confirm that gray whales existed there at least through

9159-412: The atmosphere over the oceans, keeping the British Isles and northwestern Europe mild and cloudy, and not severely cold in winter, like other locations at the same high latitude. The cold water currents contribute to heavy fog off the coast of eastern Canada (the Grand Banks of Newfoundland area) and Africa's northwestern coast. In general, winds transport moisture and air over land areas. Every winter,

9288-504: The bay from the Pacific Ocean. Magdalena, mostly to the north and facing northwest, is a long, slender, segmented island that parallels the coast a few miles north. There is a small settlement, Puerto Magdalena mostly active during whale watching season. The entire island's area is 231 km (89 sq mi). Santa Margarita, to the south, parallels the southwest-facing coast and has an area of 314 km. On its inland side

9417-572: The bay to obtain wood, catch fish and turtles , and harvest oysters . In 1908, an American fleet of sixteen battleships on a cruise around the world, the Great White Fleet , stopped in the Bay and carried out gunnery practice. In 1912, there were rumors that Japan tried to purchase the harbor from Mexico. Barbara Tuchman 's book The Zimmerman Telegram mentions both the German kaiser and

9546-662: The better documented historical catches show that it was common for whales to stay for months in enclosed waters elsewhere, with known records in the Seto Inland Sea and the Gulf of Tosa. Former feeding areas were once spread over large portions on mid-Honshu to northern Hokkaido, and at least whales were recorded for majority of annual seasons including wintering periods at least along east coasts of Korean Peninsula and Yamaguchi Prefecture . Some recent observations indicate that historic presences of resident whales are possible:

9675-475: The bones described by Lilljeborg could not belong to a living species but that they were similar to fossils that Van Beneden had described from the harbour of Antwerp (most of his named species are now considered nomina dubia ) and therefore named the gray whale Plesiocetus robustus , reducing Lilljeborg's and Gray's names to synonyms. Charles Melville Scammon produced one of the earliest descriptions of living Pacific gray whales, and notwithstanding that he

9804-570: The breeding season, it is common for females to have several mates. This single ovulation event is believed to coincide with the species' annual migration patterns, when births can occur in warmer waters. Most females show biennial reproduction, although annual births have been reported. Males also show seasonal changes, experiencing an increase in testes mass that correlates with the time females undergo oestrus. Currently there are no accounts of twin births, although an instance of twins in utero has been reported. The gestation period for gray whales

9933-412: The bulk of the population has arrived in the lagoons, 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,

10062-493: The calving lagoons and bays on the west coast of Baja California Sur . The three most popular are San Ignacio , Magdalena Bay to the south, and, to the north, Laguna Ojo de Liebre (formerly known in English as Scammon's Lagoon after whaleman Charles Melville Scammon , who discovered the lagoons in the 1850s and hunted the grays). Gray whales once ranged into Sea of Cortez and Pacific coasts of continental Mexico south to

10191-667: The east, the boundaries of the ocean proper are Europe: the Strait of Gibraltar (where it connects with the Mediterranean Sea  – one of its marginal seas  – and, in turn, the Black Sea , both of which also touch upon Asia) and Africa. In the southeast, the Atlantic merges into the Indian Ocean. The 20° East meridian , running south from Cape Agulhas to Antarctica defines its border. In

10320-544: The eastern and western North Atlantic central water since the western part is strongly affected by the Gulf Stream and therefore the upper layer is closer to underlying fresher subpolar intermediate water. The eastern water is saltier because of its proximity to Mediterranean water. North Atlantic central water flows into South Atlantic central water at 15°N . There are five intermediate waters: four low-salinity waters formed at subpolar latitudes and one high-salinity formed through evaporation. Arctic intermediate water flows from

10449-486: The eastern and western coasts of Japan and along the Chinese coast. Gray whale had not been observed on Commander Islands until 2016. The northwestern pacific population consists of approximately 300 individuals, based on photo identification collected off of Sakhalin Island and Kamchatka. The Sea of Japan was once thought not to have been a migration route, until several entanglements were recorded. Any records of

10578-458: The eastern population rather than the western. North Atlantic The Atlantic Ocean is the second-largest of the world's five oceanic divisions , with an area of about 85,133,000 km (32,870,000 sq mi). It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery , it was known for separating the New World of

10707-684: The eastern population. In mid-1980, there were three gray whale sightings in the eastern Beaufort Sea , placing them 585 kilometers (364 mi) further east than their known range at the time. Recent increases in sightings are confirmed in Arctic areas of the historic range for Atlantic stocks, most notably on several locations in the Laptev Sea including the New Siberian Islands in the East Siberian Sea , and around

10836-753: The enclosed seas well known to the Greeks: the Mediterranean and the Black Sea. In contrast, the term "Atlantic" originally referred specifically to the Atlas Mountains in Morocco and the sea off the Strait of Gibraltar and the West African coast. The term " Aethiopian Ocean ", derived from Ancient Ethiopia , was applied to the southern Atlantic as late as the mid-19th century. During

10965-450: The environment on those days. Range expansions due to recoveries and re-colonization in the future is likely to happen and the predicted range covers wider than that of today. The gray whale undergoes the longest migration of any mammal. Each October, as the northern ice pushes southward, small groups of eastern gray whales in the eastern Pacific start a two- to three-month, 8,000–11,000 km (5,000–6,800 mi) trip south. Beginning in

11094-441: The first scientific description of a species then surviving only in Pacific waters. The living Pacific species was described by Cope as Rhachianectes glaucus in 1869. 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. Although identity between the Atlantic and Pacific populations cannot be proven by anatomical data, its skeleton

11223-867: The interconnected World Ocean , it is connected in the north to the Arctic Ocean , to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south. Other definitions describe the Atlantic as extending southward to Antarctica . The Atlantic Ocean is divided in two parts, the northern and southern Atlantic, by the Equator . The oldest known mentions of an "Atlantic" sea come from Stesichorus around mid-sixth century BC (Sch. A. R. 1. 211): Atlantikôi pelágei (Ancient Greek: Ἀτλαντικῷ πελάγει , '

11352-468: The larger eastern population. In January 2011, a gray whale that had been tagged in the western population was tracked as far east as the eastern population range off the coast of British Columbia. Recent findings from either stranded or entangled specimens indicate that the original western population have become functionally extinct, and possibly all the whales that have appeared on Japanese and Chinese coasts in modern times are vagrants or re-colonizers from

11481-406: The late 17th to early 18th centuries. However, in the 2010s and 2020s there have been rare sightings of gray whales in the North Atlantic , Mediterranean , and even off South Atlantic coasts. The gray whale is traditionally placed as the only living species in its genus and family, Eschrichtius and Eschrichtiidae , but an extinct species was discovered and placed in the genus in 2017,

11610-517: The latter 2,000 km (1,200 mi). Ocean currents such as the Gulf Stream transport eel larvae from the Sargasso Sea to foraging areas in North America, Europe, and northern Africa. Recent but disputed research suggests that eels possibly use Earth's magnetic field to navigate through the ocean both as larvae and as adults. The climate is influenced by the temperatures of the surface waters and water currents as well as winds. Because of

11739-605: The limits of the oceans and seas in 1953, but some of these definitions have been revised since then and some are not recognized by various authorities, institutions, and countries, for example the CIA World Factbook . Correspondingly, the extent and number of oceans and seas vary. The Atlantic Ocean is bounded on the west by North and South America. It connects to the Arctic Ocean through the Denmark Strait , Greenland Sea , Norwegian Sea and Barents Sea . To

11868-501: The lowest values are in the high latitudes and along coasts where large rivers enter. Maximum salinity values occur at about 25° north and south , in subtropical regions with low rainfall and high evaporation. The high surface salinity in the Atlantic, on which the Atlantic thermohaline circulation is dependent, is maintained by two processes: the Agulhas Leakage/Rings , which brings salty Indian Ocean waters into

11997-514: The margins of the continents constitute about 11% of the bottom topography with few deep channels cut across the continental rise. The mean depth between 60°N and 60°S is 3,730 m (12,240 ft), or close to the average for the global ocean, with a modal depth between 4,000 and 5,000 m (13,000 and 16,000 ft). In the South Atlantic the Walvis Ridge and Rio Grande Rise form barriers to ocean currents. The Laurentian Abyss

12126-589: The marine mammal sanctuary of the Franz Josef Land , indicating possible earlier pioneers of re-colonizations. These whales were darker in body color than those whales seen in Sea of Okhotsk. In May 2010, a gray whale was sighted off the Mediterranean shore of Israel. It has been speculated that this whale crossed from the Pacific to the Atlantic via the Northwest Passage , since an alternative route around Cape Horn would not be contiguous to

12255-596: The maximum depth, the Milwaukee Deep in the Puerto Rico Trench , is 8,376 m (27,480 ft). Top large seas: The bathymetry of the Atlantic is dominated by a submarine mountain range called the Mid-Atlantic Ridge (MAR). It runs from 87°N or 300 km (190 mi) south of the North Pole to the subantarctic Bouvet Island at 54°S . Expeditions to explore the bathymertry of

12384-576: The most consequential. Columbus' expedition ushered in an age of exploration and colonization of the Americas by European powers , most notably Portugal , Spain , France , and the United Kingdom . From the 16th to 19th centuries, the Atlantic Ocean was the center of both an eponymous slave trade and the Columbian exchange while occasionally hosting naval battles. Such naval battles, as well as growing trade from regional American powers like

12513-580: The most effort into conservation of the species among the Asian nations, there are no confirmed sightings along the Korean Peninsula or even in the Sea of Japan in recent years. The last confirmed record in Korean waters was the sighting of a pair off Bangeojin , Ulsan in 1977. Prior to this, the last was of catches of 5 animals off Ulsan in 1966. There was a possible sighting of a whale within

12642-732: The most extensive and voluminous large igneous provinces in Earth's history associated with the Triassic–Jurassic extinction event , one of Earth's major extinction events . Theoliitic dikes , sills , and lava flows from the CAMP eruption at 200 Ma have been found in West Africa, eastern North America, and northern South America. The extent of the volcanism has been estimated to 4.5 × 10  km (1.7 × 10  sq mi) of which 2.5 × 10  km (9.7 × 10  sq mi) covered what

12771-477: The newborn from sharks and orcas . On 7 January 2014, a pair of newborn or aborted conjoined twin gray whale calves were found dead in the Laguna Ojo de Liebre (Scammon's Lagoon), off the west coast of Mexico. They were joined by their bellies. The whale feeds mainly on benthic crustaceans (such as amphipods and ghost shrimp ), which it eats by turning on its side and scooping up sediments from

12900-571: The north to become the source for North Atlantic deep water, south of the Greenland-Scotland sill. These two intermediate waters have different salinity in the western and eastern basins. The wide range of salinities in the North Atlantic is caused by the asymmetry of the northern subtropical gyre and a large number of contributions from a wide range of sources: Labrador Sea, Norwegian-Greenland Sea, Mediterranean, and South Atlantic Intermediate Water. The North Atlantic deep water (NADW)

13029-520: The ocean floor and rolling on to their side, (like blue whales, gray whales seem to favor rolling onto their right side) and suck up prey from the sea floor. Gray whales seem to favor feeding planktonically in their feeding grounds, but benthically along their migration route in shallower water. Mostly, the animal feeds in the northern waters during the summer; and opportunistically feeds during its migration, depending primarily on its extensive fat reserves. Another reason for this opportunistic feeding may be

13158-425: The ocean's great capacity to store and release heat, maritime climates are more moderate and have less extreme seasonal variations than inland climates. Precipitation can be approximated from coastal weather data and air temperature from water temperatures. The oceans are the major source of atmospheric moisture that is obtained through evaporation. Climatic zones vary with latitude; the warmest zones stretch across

13287-554: The only sighting of this species in the Southern Hemisphere. Photographic identification suggests that this is a different individual than the one spotted in the Mediterranean in 2010. As of July 2013, the Namibian whale was still being seen regularly. In March 2021, a gray whale was sighted near Rabat , the capital of Morocco . In April, additional sightings were made off Algeria and Italy . In December 2023,

13416-423: The original eastern and western groups could have been much more distinct than previously thought, enough to be counted as subspecies. Since the original Asian and Atlantic populations have become extinct, it is difficult to determine the unique features among whales in these stocks. However, there have been observations of some whales showing distinctive, blackish body colors in recent years. This corresponds with

13545-627: The outlines of the coasts of the Old and the New Worlds. The remainder of the ridge was discovered in the 1920s by the German Meteor expedition using echo-sounding equipment. The exploration of the MAR in the 1950s led to the general acceptance of seafloor spreading and plate tectonics . Most of the MAR runs under water but where it reaches the surfaces it has produced volcanic islands. While nine of these have collectively been nominated

13674-409: The pair returned to the same coasts at the same time of the year in 2015 again. Reviewing on other cases on different locations among Japanese coasts and islands observed during 2015 indicate that spatial or seasonal residencies regardless of being temporal or permanental staying once occurred throughout many parts of Japan or on other coastal Asia. The current western gray whale population summers in

13803-595: The pond", rather than to discuss the ocean itself. The term dates to 1640, first appearing in print in a pamphlet released during the reign of Charles I , and reproduced in 1869 in Nehemiah Wallington 's Historical Notices of Events Occurring Chiefly in The Reign of Charles I , where "great Pond" is used in reference to the Atlantic Ocean by Francis Windebank , Charles I's Secretary of State . The International Hydrographic Organization (IHO) defined

13932-427: The population hit an all-time low in 2010, when no new reproductive females were recorded, resulting in a minimum of 26 reproductive females being observed since 1995. Even a very small number of additional annual female deaths will cause the subpopulation to decline. However, as of 2018, evidence has indicated that the western population is markedly increasing in number, especially off Sakhalin Island . Following this,

14061-676: The port of Samcheok in 2015. There had been 24 records along Chinese coasts including sighting, stranding, intended hunts, and bycatches since 1933. The last report of occurrence of the species in Chinese waters was of a stranded semi adult female in the Bohai Sea in 1996, and the only record in Chinese waters in the 21st century was of a fully-grown female being killed by entanglement in Pingtan , China in November, 2007. DNA studies indicated that this individual might have originated from

14190-426: The recent sightings of Pacific gray whales in the Atlantic, suggest that another range expansion to the Atlantic may be starting. Breeding behavior is complex and often involves three or more animals. Both male and female whales reach puberty between the ages of 6 and 12 with an average of eight to nine years. Females show highly synchronized reproduction, undergoing oestrus in late November to early December. During

14319-406: The result of population increases, resulting in the whales taking advantage of whatever prey is available, due to increased competition. Feeding areas during migration seem to include the Gulf of California, Monterey Bay and Baja California Sur. Calf gray whales drink 50–80 lb (23–36 kg) of their mothers' 53% fat milk per day. The main feeding habitat of the western Pacific subpopulation

14448-419: The scars and patches associated with parasites that have either fallen off or are still attached. They have two blowholes on top of their head, which can create a distinctive heart-shaped blow at the surface in calm wind conditions. Gray whales measure from 4.9 m (16 ft) in length for newborns to 13–15 m (43–49 ft) for adults (females tend to be slightly larger than adult males). Newborns are

14577-499: The sea floor. This unique feeding selection makes gray whales one of the most strongly reliant on coastal waters among baleen whales. It is classified as a baleen whale and has baleen , or whalebone, which acts like a sieve, to capture small sea animals, including amphipods taken in along with sand, water and other material. Off Vancouver Island, gray whales commonly feed on shrimp-like mysids . When mysids are abundant gray whales are present in fairly large numbers. Despite mysids being

14706-438: The seafloor. The oldest oceanic crust in the Atlantic is up to 145 million years and is situated off the west coast of Africa and the east coast of North America, or on either side of the South Atlantic. In many places, the continental shelf and continental slope are covered in thick sedimentary layers. For instance, on the North American side of the ocean, large carbonate deposits formed in warm shallow waters such as Florida and

14835-553: The southwestern end of the known range. It is unknown whether the whales' normal range once reached further south, to the Gulf of Tonkin . In addition, the existence of historical calving ground on Taiwan and Penghu Islands (with some fossil records and captures ), and any presence in other areas outside of the known ranges off Babuyan Islands in Philippines and coastal Vietnamese waters in Gulf of Tonkin are unknown. There

14964-582: The species had not been confirmed since after 1921 on Kyushu . However, there were numerous records of whales along the Genkai Sea off Yamaguchi Prefecture , in Ine Bay in the Gulf of Wakasa , and in Tsushima . Gray whales, along with other species such as right whales and Baird's beaked whales , were common features off the north eastern coast of Hokkaido near Teshio , Ishikari Bay near Otaru ,

15093-534: The species hunted by the early New England whalers, was almost certainly the gray whale. Since the 2010s, there have been occasional sightings of gray whales in the Atlantic Ocean and in the Mediterranean Sea , including one off the coast of Israel and one off the coast of Namibia . These were presumably migrants from the North Pacific population through the Arctic Ocean . A 2015 study of DNA from subfossil gray whales indicated that this may not be

15222-551: The subtropics to the northeastern Atlantic. There this water is cooled during winter and forms return currents that merge along the eastern continental slope of Greenland where they form an intense (40–50  Sv ) current which flows around the continental margins of the Labrador Sea . A third of this water becomes part of the deep portion of the North Atlantic Deep Water (NADW). The NADW, in turn, feeds

15351-507: The summer, not making the farther trip to Alaskan waters. This summer resident group is known as the Pacific Coast feeding group. Any historical or current presence of similar groups of residents among the western population is currently unknown, however, whalers' logbooks and scientific observations indicate that possible year-round occurrences in Chinese waters and Yellow and Bohai basins were likely to be summering grounds. Some of

15480-421: The surface is usually covered with sea ice in the Labrador Sea , Denmark Strait , and Baltic Sea. The Coriolis effect circulates North Atlantic water in a clockwise direction, whereas South Atlantic water circulates counter-clockwise. The south tides in the Atlantic Ocean are semi-diurnal; that is, two high tides occur every 24 lunar hours. In latitudes above 40° North some east–west oscillation, known as

15609-428: The total volume of the Earth's oceans. Excluding its marginal seas, the Atlantic covers 81,760,000 km (31,570,000 sq mi) and has a volume of 305,811,900 km (73,368,200 cu mi). The North Atlantic covers 41,490,000 km (16,020,000 sq mi) (11.5%) and the South Atlantic 40,270,000 km (15,550,000 sq mi) (11.1%). The average depth is 3,646 m (11,962 ft) and

15738-417: 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 6 to 12 dorsal crenulations ("knuckles"), which are raised bumps on the midline of its rear quarter, leading to

15867-575: The upper layers of the circumpolar region, near the Drake Passage and the Falkland Islands. Both these currents receive some contribution from the Indian Ocean. On the African east coast, the small cyclonic Angola Gyre lies embedded in the large subtropical gyre. The southern subtropical gyre is partly masked by a wind-induced Ekman layer . The residence time of the gyre is 4.4–8.5 years. North Atlantic Deep Water flows southward below

15996-448: The waters off northernmost Alaska and Baja California Sur . Mothers make this journey accompanied by their calves, usually hugging the shore in shallow kelp beds, and fight viciously to protect their young if they are attacked, earning gray whales the moniker, devil fish. The western population has had a very slow growth rate despite heavy conservation action over the years, likely due to their very slow reproduction rate. The state of

16125-424: The western Atlantic and South Sandwich Trench (8,264 m or 27,113 ft) in the South Atlantic. There are numerous submarine canyons off northeastern North America, western Europe, and northwestern Africa. Some of these canyons extend along the continental rises and farther into the abyssal plains as deep-sea channels. In 1922, a historic moment in cartography and oceanography occurred. The USS Stewart used

16254-569: The whale'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". The same whale was sighted again on May 30, 2010, off the coast of Barcelona , Spain. In May 2013, a gray whale was sighted off Walvis Bay , Namibia. Scientists from the Namibian Dolphin Project confirmed the whale's identity and thus provides

16383-663: The whales visited the southern coasts of the Korean Peninsula, adjacent to the Island of Jeju ), Haiyang Island, the Gulf of Shanghai , or the Zhoushan Archipelago . There is no evidence of historical presence in Japan south of Ōsumi Peninsula ; only one skeleton has been discovered in Miyazaki Prefecture . Hideo Omura once considered the Seto Inland Sea to be a historical breeding ground, but only

16512-880: Was among the whalers who nearly drove them to extinction in the lagoons of the Baja California Peninsula , they were and still are associated with him and his description of the species. At this time, however, the extinct Atlantic population was considered a separate species ( Eschrischtius robustus ) from the living Pacific population ( Rhachianectes glaucus ). Things got increasingly confused as 19th century scientists introduced new species at an alarming rate (e.g. Eschrichtius pusillus , E. expansus , E. priscus , E. mysticetoides ), often based on fragmentary specimens, and taxonomists started to use several generic and specific names interchangeably and not always correctly (e.g. Agalephus gobbosus , Balaenoptera robustus , Agalephus gibbosus ). Things got even worse in

16641-407: Was estimated to be 75–80 years of age. The common name of the whale comes from the gray patches and white mottling on its dark skin. Gray whales were once called devil fish because of their fighting behavior when hunted. The gray whale is the sole living species in the genus Eschrichtius . It is the sole living genus in the family Eschrichtiidae , however some recent studies classify it as

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