I also feel that I should be more educated about whales so that I can learnt how to protect its species as it is endangered. After all, knowing about an animal species is also general knowledge, thus, being knowledgeable in such things would benefit me in the future such as looking for jobs, etc.
What are Whales?The term whale is a common name the common name for any large marine mammal which have forelimbs modified as fins, a tail with horizontal flukes and nasal openings on top of the head. The term whale is used to refer to the members of the Delphinoidea superfamily, such as dolphins and porpoises. These smaller species belong to the sub-family toothed whales, which also includes the sperm whale, killer whale, pilot whale and beluga whale The sub-family baleen whales, are filter feeders that feed on small organisms caught by straining seawater (e.g. plankton) through a comblike structure found in the mouth called baleen. This sub contains four sub-families and fourteen species including the blue whale, humpback whale, bowhead whale and minke whale.
Body parts...
Some of the whale's body parts include:
1. Blowhole - Like all mammals, whales breathe air, regulate their body temperature, warm-blooded, nurse their young with milk from mammary glands, and have some hair. Thus, the blowhole exist to allow the whales to breathe. Baleen whales have two blow holes and toothed whales have only one. The blow holes are located on top of the whales heads, allowing it to remain mostly submerged whilst breathing.
2.Teeth - Toothed whales, such as the sperm whale, possess teeth with cementum cells overlying dentine cells. Unlike human teeth, which are composed mostly of enamel on the portion of the tooth outside of the gum, whale teeth have cementum outside the gum. Only in larger whales, where the cementum has been worn away on the tip of the tooth, does enamel show.
3.Blubber - Beneath the skin lies a layer of fat called blubber, which stores energy and insulates the body.
4.Bones - Whales have a spinal column, a vestigial pelvic bone.
5. Heart - A four-chambered heart.
6.Neck - The neck vertebrae is typically fused, trading flexibility for stability during swimming.
Behaviour and reproduction...
We refer male whales as bulls, females whales as cows and newborn whales as calves. Many whales also exhibit other surfacing behaviour such as breaching and tail slapping.
Unlike most animals, whales are conscious breathers. All mammals sleep, but whales cannot afford to become unconscious for long because they may drown. It is thought that only one part of the whale's brain sleeps at a time, so they rest but are never completely asleep.
Some species, such as the humpback whale, communicate using melodic sounds, known as whale song. These sounds can be extremely loud, depending on the species. Sperm whales have only been heard making clicks, because toothed whales use echoes and can be heard for many miles. They can generate about 20,000 watts of sound at 163 decibels.
Male genitals retract into body during swimming, reducing drag and preventing injury.
Most species do not maintain fixed partnerships and females have several mates each season.
The female delivers a single calf tail-first to minimize the risk of drowning. Whale cows nurse by actively squirting milk, so fatty that it has the consistency of toothpaste, into the mouths of their young. Nursing continues for more than a year in many species, and is associated with a strong bond between mother and calf. Reproductive maturity occurs typically at seven to ten years. This type of reproductionproduces few offspring, but increase survival probability.
Whales are known to teach, learn, cooperate, scheme, and even grieve.Habitat! Endangered!
Whales inhabit all the world's oceans and number in the millions, with population growth rate estimates for various assessed species ranging from 3% to 13%. For centuries, whales have been hunted for meat and as a source of raw materials. By the middle of the 20th century, however, industrial whaling had left many species seriously endangered, leading to the end of whaling in all but a few countries.
Zoom in!
Lets zoom in at the killer whale species. This is because I think that it is a very interesting species because of its features such as its 'white eye patches' as shown from the picture at the very top. In spite of the fact that there is a picture of a killer whale on the top, I am providing
one more for convenience:
Here you see two whales jumping above the surface of the ocean.
About it...
Killer whales are the largest species of the dolphin family. They are found in all of the world's oceans, from the frigid Arctic and Antarctic regions to tropical seas. Killer whales as a species have a diverse diet, although populations often specialize in particular types of prey. Some feed exclusively on fish, particularly salmon, while other populations hunt marine animals such as sea lions, walruses and seals. Some feed even on even large whales. Killer whales have no natural predators.
Killer whales are distinctively marked with a black back, white chest and sides, and a white patch above and behind the eye. Calves are born with a yellowish or orange tint, which fades to white. Killer whales have a heavy and robust body. They also have a large dorsal fin up to 2 metres tall. Behind the fin, they have a dark grey "saddle patch" across the back.
Antarctic killer whales may have pale grey to nearly white backs. Males typically range from 6–8 metres ( long and weigh in excess of 6 tonnes (6,000 kilograms). Females are smaller, generally ranging from 5–7 metres and weighing about 3 to 4 tonnes (3,000 - 4,000 kilograms). The largest male killer whale on record was 9.8 meters (32 ft), weighing over 10 tonnes (10,000 kilograms) while the largest female was 8.5 meters (28 ft), weighing 7.5 tonnes (7,500 kilograms). Calves at birth weigh about 180 kilograms and are about 2.4 meters (8 ft) long. The killer whale's large size and strength make it among the fastest marine mammals, able to reach speeds in excess of 30 knots (56 km/h).
Types of Killer whales
Generally, there are three different types of killer whales, mainly:
1. Resident: These are the most commonly sighted of the three populations in the coastal waters of the northeast Pacific. Residents' diet consists primarily of fish and sometimes squid, and they live in complex and cohesive family groups. Female residents characteristically have a rounded dorsal fin tip that terminates in a sharp corner. They are known to visit the same areas consistently. Researchers have identified and named over 300 killer whales over the past 30 years.
2.Transient: The diet of these whales consists almost exclusively of marine animals, however, they do not eat fish. Transients in southern Alaska generally travel in small groups, usually of two to six animals. Unlike residents, transients may not always stay together as a family unit. Pods consist of smaller groups with less persistent family bonds. Transients vocalize in less variable and less complex dialects. Female transients are characterized by more triangular and pointed dorsal fins than those of residents. The gray or white area around the dorsal fin, known as the "saddle patch," often contains some black coloring in residents. However, the saddle patches of transients are solid and uniformly gray.
3.Offshore: A third population of killer whales in the northeast Pacific was discovered in 1988 when humpback whale researcher Jim Darling signaled to killer whale researchers Michael Bigg and Graeme Ellis that he saw some in open water. As suggested by their name, they travel far from shore and are believed to feed primarily on schooling fish. However, because of the large presence of scarred and nicked dorsal fins resembling that of the mammal-hunting transients, the possibility that they eat mammals and sharks cannot be dismissed. They have been seen traveling in groups of up to 60. Currently, little is known about their habits, but they can be distinguished genetically from residents and transients. Offshores appear to be shorter and females are characterized by dorsal fin tips that are continuously rounded.
White!?!?!
White killer whales occur sporadically among normal whales, but are rare.
Intelligence
Killer whales have the second-largest brains of all marine mammals. They are easily trained in captivity and are often described as intelligent animals.
"Killer" whale?
Killer whales were historically feared as dangerous, savage predators.
However, there have been very few confirmed attacks on humans by wild killer whales, none of which has been fatal.
Competition with fishermen also led to killer whales being regarded as pests.
The largest animal known to have existed...
The blue whale is the largest animal known to have existed. Its average length is 35 metres and average weight is 150,000 kilograms, compared to pygmy species's such as the pygmy sperm whale, which is around 3.5 metres in length.
Lastly, I would like to research more about the blue whale as it is, after all, the biggest animal found on the Earth.
Blue Whales
Here is a brief introduction to the blue whale:
The blue whales belong to the baleen whales family.
The blue whale's body is long and slender, and can be various shades of bluish-grey dorsally and somewhat lighter underneath. There are at least three distinct subspecies. As with other baleen whales, its diet consists almost exclusively of small krill.
Blue whales were abundant in nearly all the oceans until the beginning of the twentieth century. For over 40 years, they were hunted almost to extinction by whalers until protected by the international community in 1966. Before whaling, the largest population was in the Antarctic, numbering approximately 239,000 (range 202,000 to 311,000).
The blue whale has a long tapering body that appears stretched in comparison with the stockier build of other whales.
They have small dorsal fins, visible only briefly during the dive sequence. Located around three-quarters of the way along the length of the body, it varies in shape from one individual to another; some only have a barely perceptible lump, but others may have prominent and falcate dorsals. When surfacing to breathe, the blue whale raises its shoulder and blowhole out of the water to a greater extent than other large whales such as the fin.
Their flippers are 3–4 metres long. The upper sides are grey with a thin white border. The lower sides are white. The head and tail fluke are generally uniformly grey. The whale's upper parts, and sometimes the flippers, are usually mottled. The degree of mottling varies substantially from individual to individual.
Blue whales can reach speeds of 50 kilometres per hour (31 mph) over short bursts, usually when interacting with other whales, but 20 kilometres per hour (12 mph) is a more typical traveling speed. When feeding, they slow down to 5 kilometres per hour (3.1 mph).
I have reached the end of my research.
To sum up, the video bar on the right side may contain videos on whales, thus you can watch them by clicking the icons!
Hope you have enjoyed!!!
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