Antarctic Whales Diet Crossword HeavenType C killer whales mostly eat Antarctic toothfish (Dissostichus mawsoni). Little is known about the diet of type D killer whales, however, they have been observed. Antarctic Minke whale. Introduction to Minke Whales. The Antarctic minke whale is one of seven species of baleen whales that are also called rorquals. Clue: Antarctic waters. Antarctic waters is a crossword puzzle clue that we have spotted 7 times. There are related clues (shown below). The Antarctic Wildlife Research Fund (AWR) facilitates and promotes research on the Antarctic ecosystem. Ten species of whales are found in Antarctic waters. The diet of killer whales is often geographic or population specific: Resident killer whale populations in the eastern North Pacific mainly feed on. Antarctic Minke whale . The word rorqual is Scandinavian in origin—some say Norwegian and others say Danish—and depending on where you hear it, it can mean wrinkled or furrowed, tubed or pleated. An amazing bird that migrates between the Arctic and the Antarctic every year. This whale, which is the largest. Arctic Animals Crossword Subject: Arctic. On this page you will be able to find Black-and-white Antarctic whale crossword clue answer, last seen on on May 20, 2016. Visit our site for more popular crossword. Arctic whale crossword puzzle clue has 2 possible answers and appears in 3 publications. Search for Crossword Clue Answers, never get stuck on a crossword clue again! Find answers for almost any clue. In any case, it refers to the expandable throat grooves on the whales underside that allow them to take in massive gulps of seawater and prey while expelling the water out through the baleen, trapping the prey against the inner surface and allowing it to wash down the digestive tract. The Antarctic minke whale (Balaenoptera bonaerensis) is the largest of two minke species. The other, Balaenoptera acutorostrata (the common minke whale) has a subspecies, B. It wasn’t until the 1. It was first described in Buenos Aires and thus the species name, bonaerensis. Antarctic Minke Whale Identification and Distribution. Antarctic minke whales can reach up to 3. Their blow is low and often indistinguishable and, when they dive, their flukes are not visible, only their falcate (sickle- shaped) dorsal fin. They frequently approach vessels, crossing their bow and, in some Antarctic harbors, their curiosity draws them to small boats, including Zodiacs— instantly making them one of the favorite whale species in the Antarctic. Distinguishing between the species is made slightly easier by the fact that the common minke whale is most often found in the northern hemisphere and the Antarctic minke is found in the southern hemisphere, circumglobally. They do, however, overlap considerably with the range of the dwarf minke whale, which is the southern hemisphere subspecies of the minke. Three things that set the Antarctic minke apart are its larger size, a dorsal fin that is set farther back on the body, and asymmetrical coloration of its baleen. There are more anterior white plates of baleen on the right side of the Antarctic minke than on the left side, which is dominated by dark gray baleen. Also the dwarf minke whale has a very distinctive white patch on its flipper, unlike the light gray flipper of the Antarctic species. Both the tail fluke and the underside of the flippers are white. Antarctic Minke Whale Behavior. Spyhopping is not unknown, particularly when in the vicinity of pack ice. It is apparently used not for prey location but for orientation. Minkes are active swimmers and their sleek profiles allow for fast swimming. Antarctic Minke Whale Migration. As with many whales, migration is highly dependent on the life history of their prey and there is no question that the presence of the majority of the Antarctic minke population in the Southern Ocean in the austral summer is linked to the profusion of krill in the surface waters. They lunge through the bioluminescent schools of the shrimp- like crustaceans and gulp large quantities as do other rorqual whales. It is thought that as the harvest of humpback and blue whales peaked in the early 2. Antarctic minkes increased as a result of the increased food availability. Early on the considerably smaller minkes were less desirable as a harvestable species. Some current ecological models suggest that, as blue whales gradually increase in number with decreased harvest pressure, the Antarctic minke will gradually decrease. In Antarctica minke density increases beginning in November, peaks in January and then declines again in February. After that their movements are less understood. They are known to generally be in the pelagic, or open ocean, beyond the continental shelf in the lower latitudes around Australia from April to September and have been noted off Brazil from June through December, but age classes and sexes differ. And there have been numerous records of minkes over- wintering in the Antarctic as well. Antarctic Minke Whale Breeding. While the biology of their breeding cycle is incomplete, it is generally agreed that they breed in the lower latitudes with mating occurring June through December. There does not appear to be much feeding in these months, with the Antarctic minkes assuming the life style of many of the rorquals in that they bulk up when the food is plentiful and slack off in the breeding season. Males reach sexual maturity when they are approximately eight years old (2. With gestation lasting about 1. May and June, generally in the vicinity of the relatively warmer waters of the Antarctic Convergence. Newborns are about nine feet long and weigh 1,0. By the time they are weaned five months later they have reached at least 1. Their life span is even less understood, with most information coming from harvest data. It is estimated that the Antarctic minke whale provides up to 8. Southern Ocean. Antarctic Minke Whale Population. Issues with distinguishing one species from the other have hampered attempts to accurately estimate the population of the Antarctic minke. However, in 1. 98. Antarctic minke whale - Wikipedia. The Antarctic minke whale or southern minke whale (Balaenoptera bonaerensis) is a species of minke whale within the suborder of baleen whales. It is the second smallest rorqual after the common minke whale and the third smallest baleen whale. Although first scientifically described in the mid- 1. Once ignored by the whaling industry due to its small size and low oil yield, the Antarctic minke was able to avoid the fate of other baleen whales and maintained a large population into the 2. It is primarily restricted to the Southern Hemisphere (although vagrants have been reported in the North Atlantic) and feeds mainly on euphausiids. Taxonomy. After bringing it ashore he brought it to the attention of the German Argentine zoologist Hermann Burmeister, who described it as a new species, Balaenoptera bonaerensis, the same year. Williamson was the first to describe a dark- flippered form in the Southern Hemisphere, based on three specimens, a pregnant female taken in 1. British factory ship Balaena. All three had uniformly pale gray flippers and bicolored baleen, with white plates in the front and gray plates in the back. Rice supported these conclusions in his seminal work on marine mammal taxonomy, giving what he called the . Other organizations followed suit. Divergence. Both were caught in the northeastern North Atlantic by Norwegian whaling vessels. The first, an 8. 2. Spitsbergen (7. 8. The second, a pregnant female taken off northwestern Spitsbergen (7. Her female fetus, in turn, was fathered by a North Atlantic common minke, demonstrating that back- crossing is possible between hybrids of the two species. The longest caught off Brazil were an 1. At sexual maturity, females average 8. Calves are estimated to be 2. They have a narrow, pointed, triangular rostrum with a low splashguard. Their prominent, upright, falcate dorsal fin . About half of individuals have a light gray flare or patch on the posterior half of the dorsal fin, similar to that seen in species of dolphins in the genus Lagenorhynchus. They are dark gray dorsally and clean white ventrally. The lower jaw projects beyond the upper jaw and is dark gray on both sides. These streaks appear to be more prominent and consistent on this species than on either the common or dwarf minke. Most also have a variably colored . A light gray variably shaped double chevron or W- shaped pattern (analogous to a similar pattern seen on their larger cousin the fin whale). This broadens to form a light gray shoulder patch above the flippers. Like common and dwarf minkes, they have two light gray to whitish swaths, called the thorax and flank patches, the former running diagonally up from the axilla and diagonally down again to form a triangular intrusion into the dark gray of the thorax and the latter rising more vertically along its anterior edge and extending further dorsally before gradually sloping posteriorly to merge with the white of the ventral side of the caudal peduncle. A dark gray, roughly triangular thorax field separates the two, while a narrower dark gray shoulder infill separates the thorax patch from the shoulder patch. Two light gray, forward directed caudal chevrons extend from the dark gray field above, forming a whitish peduncle blaze between them. The smooth sided flukes, usually about 2. Some small, dark gray speckling may be present on the body. Instead, their narrow, pointed flippers, about one- sixth to one- eighth of the total body length, are normally either a plain light gray with an almost white leading edge and a darker gray trailing edge or two- toned, with a thin light gray or dark band separating the darker gray of the proximal third of the flipper from the lighter gray of the distal two- thirds. Unlike the dwarf minke, the dark gray between the eye and flipper does not extend unto the ventral grooves of the throat to form a dark throat patch; there is instead an irregularly shaped line running from about the level of the eye to the anterior insertion of the flipper, merging with the light gray of the shoulder patch. They are two- toned, with a dark gray outer margin on the posterior plates and a white outer margin on the anterior plates . The dark gray border occupies about one third of the width of the plates (ranging from about one- seventh to over half of its width), with the average width being greater on the left side than on the right. In contrast, dwarf minkes have smaller baleen plates of only 2. Antarctic minkes have an average of 4. In the western South Atlantic, they have been recorded off Brazil from 0. In the spring (October. In the spring (October. The first was marked off Queen Maud Land (6. Over twenty individuals marked with these Discovery tags showed large- scale movements around the Antarctic continent, each moving more than 3. The first was marked off the Ad. The second was marked north of Cape Adare (6. Both were marked and recovered in January. The Report of the Scientific Committee acknowledged that this estimate is subject to some degree of negative bias because some minke whales would have been outside the surveyable ice edge boundaries. Both become physically mature at about 1. After a gestation period of about 1. After a lactation period of about six months, the calf is weaned at a length of 4. The calving interval is estimated to be about 1. Peak calving is from May to June, while peak conception is from August to September. Females may live up to 4. In the Southern Ocean, over 9. Antarctic krill (Euphausia superba); E. Rare and incidental items include calanoidcopepods, the pelagic amphipod. Themisto gaudichaudii, Antarctic sidestripes (Pleuragramma antarcticum), the crocodile icefish. Cryodraco antarcticus, nototheniids, and myctophids. The few that did have food in their stomachs had all preyed on euphausiids, mainly Thysanoessa gregaria and E. Individuals were often found with orange- brown to yellowish patches of the diatom. Cocconeis ceticola on their bodies . Of a sample of whales caught by a Japanese expedition along the ice edge, one- fifth was infested with cyamids (those from one whale were identified as Cyamus balaenopterae). Several hundred of these whale lice can be found on a single whale, with an average of 5. The copepod Pennella was found on only one whale. Cestodes were commonly found in the intestines (one example was identified as Tetrabothrius affinis). The average group size in the Antarctic was about 2. Off South Africa, immature animals predominate from April to May, while mature whales (mainly males) dominate from June onwards . Over a quarter of the females off South Africa were found to be lactating, whereas lactating females are very rare in the Antarctic . Mature males dominate in middle latitudes, while mature females predominate in the higher latitudes of the pack ice zone . After making a series of shorter dives during which they will surface anywhere from two to fifteen times, they will make a longer dive of up fourteen minutes. Each sweep has a duration of 0. The bio- duck call, first described in the 1. Oberon- class submarines for its purported resemblance to the quack of a duck, consist of a series of anywhere from three to a dozen pulse trains that range from 5. Hz and have a peak frequency of about 1. Hz . They are repeated about every 1. Their source remained a mystery for decades until attributed to the Antarctic minke whale in a paper published in 2. Two were saved, both being used for fresh meat (one had only yielded two barrels of blubber). The chemist Christopher Ash, who had served on the British factory ship Balaena during this time, stated that they were small enough to be lifted by their tails using a 1. Though the Soviets had caught several hundred in the 1. Japanese expedition). Despite these precautions, the quota was exceeded by 7. The first research program, Japanese Research Program in the Antarctic (JARPA), began in 1. Antarctic minkes were caught. The quota and catch soon increased to 3. In 2. 00. 5- 0. 6, the second research program, JARPA II, began. In its first two years, in what Japan called its . The quota was reached in the first season, but due to a fire, only 5. Antarctic minkes were caught in the second. In 2. 00. 7- 0. 8, because of constant harassment from environmental groups, they failed to reach the quota again, with a catch of only 5. Beginning in 1. 96. Natal, South Africa, mainly to supplement the dwindling supply of larger species, particularly the sei whale. A total of 1,1. 13 whales (nearly all Antarctic minke, but a few dwarf minke as well) were caught off the province between 1. They were taken by whale catchers of 5. Durban (2. 9. Gunners refused to take minkes early in the day, because sharks devoured any minke carcasses that were flagged, forcing the catchers to tow them during the chasing of other whales and thus slowing them down. They also could not use asdic, as it frightened them and lead to protracted chases. The season lasted from February to September, with a peak in the last month of the season. Over 1. 4,0. 00 were caught between 1. They were caught by a succession of whale catchers . The season lasted from June to December, with a peak in either September or October. The former have been reported off Peru and Brazil, and the latter off South Australia. All involved calves or juveniles. However, the IUCN states that the population size is . It is listed on Appendix II. In Wilson, D. E.; Reeder, D. M. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. ISBN 9. 78- 0- 8. IUCN Red List of Threatened Species. International Union for Conservation of Nature. Retrieved 7 October 2. Paper SC/5. 8/IA1. International Whaling Commission Scientific Committee, pp. Proceedings of the Zoological Society of London: 7. Gray, J. E. Annals and Magazine of Natural History. Annals and Magazine of Natural History. Proceedings of the Zoological Society of London. Scientific Reports of the Whales Research Institute.
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