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Blue whales are the largest of the baleen whales, the longest is a female whale captured in Antarctic waters between 1904 and 1920, 33.58m long, weighing 170 tons.
Size comparisonThe blue whale is the largest animal that has ever lived on Earth. The largest known creature from the age of dinosaurs was the Mesozoic Argentinosaurus, which was estimated at 90 tons. How much the largest blue whales weighed is uncertain. Most of the data is taken from blue whales hunted in Antarctic waters in the first half of the 20th century, measured by whalers who were not well versed in standard animal measurements. The longest whales on record were two females at 33.6 and 33.3 meters. But the reliability of these measurements is disputed. Scientists at the U.S. National Marine Mammal Laboratory measured the longest whale at 29.9 meters, roughly as long as a Boeing 737 or three double-decker bus**** cars.
The blue whale's head is so large that 50 people can stand on its tongue. Its heart is as big as a small car. Babies can crawl through its arteries, and a newborn blue whale calf weighs more than an adult elephant. For the first seven months of its life, a young whale drinks 400 liters of breast milk a day. Young whales grow rapidly, gaining 90 kilograms of weight every 24 hours.
Because of the blue whale's enormous size, we can't weigh it directly. Most blue whales that are killed are not weighed whole; whalers cut them down to the right size before weighing them. Because of the loss of blood and other bodily fluids, this approach underestimates the weight of the blue whale. Even so, whales as long as 27 meters have been documented as weighing 150-170 tons, and NMML scientists believe that whales as long as 30 meters are estimated to weigh more than 180 tons. The largest blue whale accurately measured by NMML scientists currently weighs 177 tons.
Edited Physical Characteristics
Females are larger than males, and southern blue whales are larger than northern blue whales. Above view, the muzzle is broad and flat. The dorsal fin is small, about 0.4m high, located in the rear 1/4 of the body. The flipper is small, its length accounts for 15% of the body length. The caudal fin is 1/3 to 1/4 as wide as the body length, and the posterior margin is straight. There are 55 to 88 stinging grooves, the longest of which reaches the umbilicus. There are 270-395 whisker plates on each side. The dorsal surface of the body is dark pale gray-blue, the ventral surface is slightly lighter, and the mouth and whiskers are black.
Blue whales differ from other species of whales in that while other species appear short and stout, blue whales have a long vertebral body that looks like it has been stretched. The head is flat and U-shaped, with a distinctive ridged protrusion from the upper lip to the dorsal stomata, and a dense concentration of baleen plates at the front of the mouth, with about 300 baleen plates (roughly 1 meter long) overhanging the upper jaw and penetrating about half a meter into the mouth. 60-90 grooves (known as ventral folds) run parallel to the body along the throat. These folds are used to expel seawater after a massive swallow (see section on "Predation").
The blue whale's dorsal fin is small and is only visible briefly during dives. The shape of the dorsal fin varies from individual to individual; some have only a just visible bulge, while others have a very distinctive, sickle-shaped fin. The dorsal fin is located roughly three-quarters of the way down the length of the body. When it is time to surface to breathe, blue whales raise their shoulders and stomatal area out of the water to a much greater extent than other large cetaceans, such as fin whales and pompano whales. This often serves as a useful cue for identifying marine species. When breathing, a spectacular vertical column of water (up to 12 meters, typically 9 meters) emitted by a blue whale can be seen from thousands of meters away if the wind is calm. Blue whales have a lung capacity of 5,000 liters.
The blue whale's flippers are 3-4 meters long. The upper part is gray with white narrow sides. The lower part is all white. The head and tail fins are usually gray. But the back and sometimes the flippers are usually ombre. The extent of the variegation varies markedly from individual to individual. Some may be gray all over, while others are dark blue, with a fair amount of gray and dark blue mixed together (grey-blue).
Blue whales can sprint at speeds of up to 50km/h (30mph) when interacting with other whales, but the usual swimming speed is 20km/h (12mph). When feeding, the speed drops to 5km/h (3 mph). Blue whales in the North Atlantic and North Pacific raise their tail fins when diving, most others do not.
Edit Habits
Blue whales feed on plankton, with a staple diet of krill (krill). A blue whale consumes 2 to 4t of food per day. Swimming speed when feeding 2 ~ 6km / h, migratory 5 ~ 33km, forced by a maximum of 20 ~ 48km. generally 10 ~ 20 small dive followed by a deep dive, shallow dive interval of 12 ~ 20 seconds, deep dive can last 10 ~ 30 minutes. The fog column is narrow and straight, 6-12m high. blue whales are sexually mature at about 10 years old, the northern blue whales calve and mate in late fall and early winter, the southern hemisphere is in the southern winter mate, July is the peak season. The difference between the northern and southern hemispheres is half a year. The gestation period is 10 to 11 months, and the calf is 6 to 7 meters long and weighs about 6 tons. Lactation lasts half a year, and at weaning the calf can be up to 16 m. Estimates of the maximum age range from 30 to 80-90 years. The whales court by calling.
Editorial Breeding
Blue whales breed in the winter. A mother whale carries her calf for a year before giving birth. Just after giving birth, the calf is about 7.5 meters long and weighs about 6 tons, and after 24 hours of breastfeeding, it can gain about 100 kilograms in weight, an average of about 75 grams per minute. After 7 months of breastfeeding, a young whale can weigh about 23 tons, be about 16 meters long, and begin to learn to open its mouth to swallow all kinds of plankton. Young blue whales are not considered adults until they are 5 years old.
Editing this section of the prey
Blue whales only eat krill, which are different species of plankton depending on the area of the ocean. In the North Atlantic, the northern krill, Thysanoessa raschii, Thysanoessa inermis, and Thysanoessa longicaudata are the blue whale's main diet. In the North Pacific Euphausia pacficia, Thysanoessa inermis, Thysanoessa longipes, Thysanoessa spinifera and Nyctiphanes symplex are the main food items; while in the Antarctic, Antarctic krill, Euphausia crystallorophias and Euphausia vallentni are the main food for blue whales.
Blue whales usually feed on the densest krill populations they can find, which means that blue whales need to feed in deep water (over 100 meters) during the day before they can come to the surface to feed at night. The dive time for blue whales during foraging is typically 10 minutes. Dives of 20 minutes are not uncommon, with the longest recorded dive being 36 minutes (Sears, 1998). Blue whales feed by swallowing large groups of krill at a time, along with large amounts of seawater. The belly and tongue are then squeezed to expel the seawater through the baleen plates. Once the mouth is clear of seawater, the blue whale swallows the remaining krill that cannot pass through the baleen plates.
Edited Life Cycle
Blue whales begin mating in the fall and continue until late winter. We don't yet know anything about mating behavior or breeding grounds. Females calve once every 2-3 years, usually in early winter after a 10-12 month gestation period. Juvenile whales weigh about 2 ? tons and are about 7 meters long. They are weaned after about 6 months, by which time they have doubled in length. Blue whales are generally sexually mature at 8-10 years of age, when males are at least 20 meters long (longer in the Southern Hemisphere). Females are relatively larger, becoming sexually mature at about 5 years of age, when they are about 21 meters long.
Scientists estimate that blue whales live to be at least 80 years old; however, because individual records do not go back to the whaling era, it will be many years before the exact lifespan of the whales can be determined. The longest recorded study of a single individual is 34 years, in the northeast Pacific (reported by Sears in 1998). The natural predator of blue whales is the orca, and Calambokidis et al. (1990) found that 25% of adult blue whales had injuries from orca attacks. But there is no definitive data on mortality from attacks.
Blue whale strandings are uncommon, and because of their specialized group structure, no group stranding has ever been heard of. But when strandings do occur, they are doubly publicized, and in 1920 a blue whale stranded on a beach on the Isle of Lewis in the Outer Hebrides, Scotland, after being shot in the head by a whaler but the harpoon did not explode. Like other animals, blue whales instinctively hold on to their breath at all costs, and stranding keeps them from getting bored to death, and the two whalebone heads standing along the avenue on the Isle of Lewis attracted a large number of tourists.
Editorial vocalizations
Blue whales are the loudest animals in the world. Cummings and Thompson (1971) and Richardson et al. (1995) stated that the blue whale's voice was estimated to reach 155-188 decibels at the source by measuring it at a distance of 1 meter from the blue whale referenced to a pressure of one millipascal. Even taking into account the different impedances of water and air, with different standard reference pressures, the equivalent sound range in air is still 89-122 dB. As a comparison, the sound of a wind drill is about 100 decibels. But humans may not be able to appreciate that blue whales are the loudest animals. All blue whale populations vocalize at a fundamental frequency of 10-40 Hz, while the lowest frequency humans can detect is 20 Hz. Blue whale sounds last from 10-30 seconds. The voices of blue whales off the coast of Sri Lanka have been recorded repeating a four-note "song" for two minutes at a time, reminiscent of the humpback whale song. The researchers believe that because the phenomenon has not been seen in other populations, it may be unique to the subspecies B. m. brevicauda (pygmy).
Scientists do not know why blue whales vocalize, and Richardson et al. (1995) suggest the following reasons:
1. Maintaining distance between individuals
2. Similar and individual recognition
3. Environmental messaging (e.g., foraging, warnings, courtship)
4. Maintaining group bonds (e.g., communication between females and males)
5. communication between females and males)
5. localization of geomorphic features
6. localization of food
(adapted from 2002 NMFS Biological Opinion paper)
Editing this section on stocks and whaling
Blue whales are not easy to kill or preserve. The speed and strength of blue whales meant that they were not usually a target for early whalers, who chose to hunt sperm and right whales. When the populations of these two species declined, the number of baleen whales whalers chose to kill increased, including blue whales.In 1864, Norwegian Svend Foin fitted out his ships with harpoons specially designed to catch large whales. Though initially cumbersome, the method quickly caught on, and by the end of the 19th century the blue whale population in the North Atlantic began to decline.
The killing of blue whales grew rapidly around the world, and by 1925, the United States, Britain and Japan followed Norway in joining the hunt, using "whalers" to kill and raise the whales to huge "factory ships" for processing. In 1930, 41 ships*** slaughtered 28,325 blue whales. Toward the end of World War II, the blue whale population was close to extinction, and in 1946 quotas were introduced for the first time to limit the international trade in whales. These quotas were ineffective because the agreement did not take into account the differences between species. Species that were rare in numbers could be hunted to the same extent as more numerous species. By the 1960s, when the International Whaling Commission began banning the killing of blue whales, 350,000 blue whales had been killed and the worldwide population had been reduced to less than 1% of what it was 100 years earlier.
Edit Distribution
Worldwide distribution, with the Antarctic waters having the largest effect, mainly temperate and frigid cold waters with water temperatures of 5 to 20 degrees Celsius, and a few whales have come to swim in the Yellow Sea and Taiwan waters. Blue whales are one of the most important economic species, with a large amount of fat. International regulations use the oil production of blue whales as a unit of conversion, i.e. 1 blue whale = 2 fin whales = 2.5 humpback whales = 6 baleen whales. Since the beginning of modern whaling, blue whales have been indiscriminately hunted, and at its peak in 1930-31, nearly 30,000 blue whales were hunted around the world in a single year. 1966, the International Whaling Commission declared blue whales to be a no-take conservation target. There were at least 200,000 blue whales before exploitation, and it is now estimated that there are up to 13,000. According to a statistical report published by the IWC in 1989, there are now only 200-453 survivors. That's based on surveys in the southern hemisphere after eight years of being on the verge of extinction.
Since whaling was banned, the global population of blue whales has remained largely unchanged at about 3,000-4,000. Blue whales have been listed as endangered on the Red List of Threatened Species since its creation. The blue whale population located in the northeastern Pacific Ocean is the largest, consisting of about 2,000 individuals concentrated between Alaska and Costa Rica, but commonly found in California during the summer months. This population is the hope for a rebound in blue whale numbers long afterward. In some cases they drift into the Pacific Northwest; there have been documented occurrences between Kamchatka and the northern tip of Japan.
The Southern Ocean population of blue whales numbers between 750 and 1,200, and the way this population migrates is not well understood. They may or may not be distinguishable from the stock that occurs in indeterminate numbers off the northeast coast of Sri Lanka from time to time. A portion of the Southern Ocean stock of blue whales is close to the east coast of the South Pacific. In Chile, blue whales have been found gathering to feed off the coast of Chiru Island, so the Chilean Center for Cetacean Conservation, supported by the Chilean Navy, is conducting extensive research and conservation.
There are two populations of blue whales living in the North Atlantic. The first is located in Greenland, Newfoundland, Nova Scotia and the Gulf of St. Lawrence. It is estimated that there are about 500 of them. The second is further east, occurring in the Azores in the spring and in Iceland in July and August; the whales are hypothesized to move along the Mid-Atlantic Ridge between these two volcanic islands. In addition to Iceland, though and its rarity, blue whales are also found further afield on the islands of Svalbard and Jan Mayen. Scientists are not sure where these blue whales winter. The entire North Atlantic population numbers between 600 and 1,500.
Humans pose a threat to the recovery of blue whale populations, with polychlorinated biphenyls (PCBs) chemicals collecting within their bloodstreams, leading to poisoning and premature deaths, as well as the noise pollution caused by increasing ocean transportation, which muffles the whales' voices and makes it difficult for them to find mates.
Editorial Information
The blue whale is not only the largest cetacean, but also larger than the largest dinosaur that ever lived on Earth, and is the largest of all animals known to have lived since ancient times, typically measuring 2,400-3,400 centimeters in length and weighing 150,000-200,1000 kilograms, which means that it is the equivalent of 25 That is to say, it is equivalent to the weight of more than 25 African elephants, or 2,000-3,000 human beings combined. Fortunately, due to the buoyancy of the ocean, it does not need to support its weight with the same effort as a land animal, and its large size also helps to maintain a constant body temperature. The blue whale has a light blue or mouse-gray body all over, with a light-colored, finely mottled dorsal surface, a white chest with white spots and 20 or more pleated grooves, and a belly also covered with pleats up to the umbilicus with ochre-colored yellow spots. Females have cleavage on either side of the genital pores, containing elongated nipples. The head is relatively small and flattened, with 2 blowholes located on the top of the head, the muzzle is wide, the mouth is large, the mouth is toothless, and the maxilla is wide, projecting upwards in a curved shape, bearing black whisker plates, as many as 300-400 on each side, and measuring 90-110 cm in length and 50-60 cm in width. A lot of wax accumulates in the eardrum every year, and its age can be judged according to the thickness of the wax. There is also a white callus on its maxilla, which used to be a place for hair growth, but later, when the hairs have all degenerated, it leaves a warty, superfluous piece that becomes a breeding ground for parasites. Since this callus is different in each individual, like a differently shaped "hat", it is possible to distinguish between the different individuals. The dorsal fin is particularly short, less than 1.5% of the body length, and the fin limbs are not too long, about 4 meters, with 4 toes, the rear edge of which has no wavy notch, and the tail is broad and flat. The entire body is streamlined, looks like a razor, so it is also known as the "razor whale".
The blue whale's body is so huge that a tongue is 2,000 kilograms, the skull 3,000 kilograms, the liver 1,000 kilograms, the heart 500 kilograms, the circulation of 8,000 kilograms of blood, and the male's testicles are 45 kilograms. If you straighten its intestines, there are 200-300 meters, the blood vessels are thick enough to fit a child, the dirty wall is more than 60 centimeters thick, and the male beast's penis is up to 3 meters long. Its strength is also amazingly large, the power emitted is about 1500-1700 horsepower, is called the animal world deservedly Hercules.
Blue whales are distributed from the South Pole to the North Pole between the northern and southern hemispheres in the major oceans, especially near the South Pole near the ocean in the number of more, but less common in tropical waters. In our country in the Yellow Sea, the East China Sea, the South China Sea, including the southern and southwestern waters of Taiwan. Despite the huge size, usually move slowly, often stationary, but can sink and float freely in the water, the tail swings flexibly, both forward power, but also plays the role of the rudder, forward speed up to 28 kilometers per hour.
Blue whales inhabiting the bay mostly by land in the river water washed into the extremely rich organic matter, so that the water quality is very fertile, promoting a large number of plankton reproduction. And dense plankton, and attracted the body glittering with diamond blue light of the large groups of krill. Incredibly, the blue whale, a mega-animal, feeds mainly on tiny animals like krill. Its stomach is divided into four, the first stomach for the esophagus part of the expansion and become, so the appetite is huge, once can swallow 2 million krill, every day to eat 4,000-8,000 kilograms, if the belly of the food is less than 2,000 kilograms, there will be a feeling of hunger. Krill is the most abundant animal in the world and is widely distributed in both the North and South Polar sea areas, and it is due to such an abundance of food and living in water with no supportive weight limit that the blue whale can develop to such a huge size. It spends most of the day with its mouth wide open swimming in the dense plankton thicket, two rows of plate-like baleen on the mouth like a sieve, and there are many folds in the stomach like an accordion's bellows, which can be enlarged and narrowed so that it can swallow seawater and krill together, and then the mouth closes, so that seawater from the baleen slit out, filtered down to the small shrimp and small fish, and swallowed and ate them. Blue whale food and other shrimp, small fish, jellyfish, diatoms, as well as a variety of plankton, etc., in contrast, living in the northern waters of the blue whale, the size of the Antarctic than living in the nearby waters of the small, it is generally believed that this has a close relationship with its food and the number of types and quantities.
Blue whales live in the sea, but also with other mammals, with lungs for breathing, lungs weighing more than 1,000 kilograms, can hold more than 1,000 liters of air. Such a large lung capacity, so that the number of times it breathes greatly reduced, about every 10-15 minutes before the surface of the water to breathe once. When it breathes, it first expels carbon dioxide and other exhaust gases from its lungs through its nostrils, and then inhales fresh oxygen. Whenever its head exposed to the surface of the water to breathe, the first body of carbon dioxide and other exhaust gas out of the body, this powerful burning air flow out of the nostrils, the height of the jet can reach about 10 meters, and the nearby sea water is also rolled out of the sea, so that the blue sea appeared in a spectacular column of water, far away from home, like a sea fountain, but also issued as if the train's whistle generally loud sound, people called "jet tide", and then inhale the fresh oxygen. People call it "jet tide". People can determine the location of the blue whale according to the sound of the jet, the height and shape of the jet tide. Blue whales live in all oceans. China's waters are extremely rare to see, the Yellow Sea and the South China Sea has appeared in the records of blue whales, generally not more than 100 meters. But some individuals can dive to a depth of 500 meters, diving time can last 10 to 20 minutes, followed by a continuous 8 to 15 times the jet, the jet of water can be as high as 9.1 meters.
Generally, cetaceans do not raise their tails before diving, but the blue whale always exposes its tail to the water before diving, sometimes leaping out of the water as high as it can, and then dives 30-40 meters into the water quickly to look for food. It also likes to hit the water with its tail fin, a pastime that has many uses and purposes, perhaps as a game, or to get the attention of its companions, or perhaps to get rid of parasites on its skin.
While groups of 50-60 blue whales have been seen, they generally rarely form groups, and most are solitary, or only 2-3 together. The bipartite whales are very friendly with each other, swimming, diving, feeding and breathing together like lovebirds, often leaving a wide channel behind them. 3 whales together, mostly females and a calf close together, with the males trailing behind, are about 3 meters apart.
Blue whales breed in the winter, and females typically give birth every 2 years, with pregnancies lasting 10-12 months and only one calf per litter. The newborn calf is 6-8 meters long and weighs about 6,000 kilograms. In order to prevent asphyxiation, the female has to lift the calf out of the water for the first breath of air, and later it will be able to breathe on its own. Female beast of a pair of nipples long in the genital pore on both sides, nursing when swimming in the upper layer of seawater, the cub is closely followed by the female beast behind the bottom, because the cub does not have the ability to move the lips, can not hold the nipple sucking milk, the female beast by virtue of the contraction of the muscles, will be the milk directly ejected into the mouth of the cub, which is also it is the main living in the water is a very good adaptation. Blue whale milk is very rich in nutrients, of which the fat content is 10 times that of cow's milk, and the cub sucks milk in more than 1,000 kilograms per day, so it develops very quickly, and after 8 months, it can increase to 15 meters, and its weight grows to 23,000 kilograms, and it can open its own mouth to eat all kinds of plankton. At the age of two and a half to three years, the body length can exceed 20 meters. Sexual maturity occurs at about 8 to 10 years of age, and life expectancy is usually more than 50 years, with a maximum of 90 to 100 years.
Blue whales make the loudest sounds of any animal. Blue whales use a low-frequency, deafening sound when communicating with their partners. The sound, which sometimes exceeds 180 decibels, is louder than the sound you hear when a jet plane takes off from a runway, and sensitive instruments have detected blue whales from as far away as 80 kilometers.
Blue whales are taxonomically classified as mammals, cetaceans, fin whales, and fin whales. As a result of years of competitive hunting in the world's major oceans, blue whales with a body length of more than 25 meters are now rare. In addition, the large number of scaled shrimp fishing, also makes the blue whale's foraging activities have been greatly affected. According to statistics, half a century ago, there were still about 300,000 blue whales in the world, and by 1974 there were still 25,000, but now there are only about 2,000 left. Although there has been an international limit on the number of blue whales killed each year since 1932, the outlook for the world's largest animal remains precarious!