Killer Whales. (Orcas). Bryn Lindsay & Shahill Sahib. General Information.
Bryn Lindsay & Shahill Sahib
The killer whale (orca) are said to be whales but are not, they are actually members of the dolphin family and is the biggest dolphin. Orcas are really good at hunting but fortunately there have been no humans killed the orca. Did you know that killer whales are often compared wolves because they are both top predators and it is also sometimes called “ the wolf of the sea”.
Killer whales have very good main senses. Killer whales can hear a far range of sounds. killer whales have very good vision in and out of water. It is not known that orca have or not have some sort of taste sense. Killer whales are considered by one of the most intelligent of the Antarctic mammals.
Orcas grow a size of maximum of 33 feet long (10 m) long. And a minimum of 27 feet (8 m) long. They weigh more than 8,000 – 12,000 pounds ( 3.600 – 5.400 Kg). The male orca is the largest member of the dolphin family.
Orcas are very efficient hunter that eat a whole variety of fish and animals. They eat fish, squid, shark, marine animals (including seals and whales), turtles, sea lions, walruses, otters, cetaceans, polar bear, reptiles, octopus and birds ( penguins and gulls ). They have been known to prey young blue whales and other large whales. While eating they swallow their prey whole. Killer whales eat around about 3 - 4% of their own body weight in a day, while a calf can eat up to 10% of their body weight in a day. They eat about 67% of fish, 27% of marine mammals and 6% of squid in the Antarctic.
Orcas live in oceans world wide. They range from tropical waters to arctic waters. they live in both shallow and deep water. They occasionally venture up estuaries but don’t go too far from the sea.
The breeding starts in mid winter and may go to the length of early spring. They will only breed in or near warm waters. The calf is born tail first, which is usual for cetaceans and near the surface between October and march.
The calf straight away swims to the surface within 10 seconds of birth for its first breath. Within 30 minutes of birth the baby whale can swim.
The orcas are thought to have a slightly different language to communicate with other pods (groups) to another. Orca don’t make, seasonal migrations. They may however, cover an area of hundreds of miles (or kilometres) in order to find its prey. Orcas breath air at the surface of the water through their blowhole located near their head. Orcas are very fast swimmers. It can reach speeds of up to 30mph (48km) in short periods in order to catch their prey
Orcas have very tall, straight that reach a size of 1.8 meters. They are pitch black and paper white. They have a white patch around each eye and a grey patch behind their dorsel fin. They have a white underside, large paddle like fins and a indistinct beak. All orcas have scars and cuts on their dorsel fins and can be recognised by the size of their fin.
Recent studies shows that orcas are among the most contaminated marine mammals in the whole world. Pollution and chemicals contamination make orcas more in danger to disease and likely cause birth difficulties. Whalers another threat to whales, whalers go out in boats and hunt whale where ever they can find them.
Orcas generally live in small groups called pods. These pods contain from 6-40 whales. the friendships between whales I pods last for a life time. They all hunt together in a sophisticated manner. They attack really large animals and then share it between them. Pod members defend the young, the sick and the injured.
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