Killer Whale

What is a killer whale? A killer whale is considered a whale to most people, but its is actually the largest of all dolphins and one of the most superior predators in the world (Killer Whale, National Geographic). The scientific name for a killer whale is Orcinus Orca. The killer whale falls into the kingdom Animalia, the phylum Chordata, the class Mammalia, and the order Cetacea (Killer Whales , NOAA). Killer whales or orcas are one of the most intelligent species world. Orca’s are widely distributed in all parts of the ocean even the tropics (Diagram A).The estimated population of a killer whale is fifty thousand to about one hundred thousand. (7 Things About Killer Whales, Take Part) . Killer whales are solid black and white, they also have a gray patch on their back called a â€Å"cape† or a â€Å"saddle† . The top(dorsal) side of the dolphin is black, including the pectoral flippers. The bottom (ventral) side is mostly white. The oval white spots behind the eyes are called â€Å"eyespots†. The size of a killer whale varies depending on the location of the dolphin. Adult killer whale females are smaller than adult males.A killer whale has a fusiform body shape. A fusiform body shape has less drag, which means that it is an efficient swimmer. The pectoral fin of a killer whale, which is very similar to a human hand (Diagram B), is used to steer and the flukes, or tails, are used to stop. The dorsal fin is used to help stabilize the whale when it swims at high speeds it is also encircled by veins to help manage the body temperature. The killer whale’s eyes are on both sides of the head, its about the same size of the eyes of the cow. The ears are a tiny opening just behind the eyes.Covered by a muscular flap is the blowhole, this is what the killer whale breathes through. (Physical Characteristics, Sea World). The killer whale has four senses taste, touch, hearing and eyesight. Killer whales do have taste buds, they prefer a specific food fishes. A killer whale has a very well developed sense of touch. Orcas have great vision both in and out of water. A marine mammals eyesight is grater than a land mammals. Often in the darker sides of the ocean their eyesight becomes weak and make its difficult to see their prey, in this case they use their sound receptors to navigate.Orcas have very well developed hearing. Recent studies have shown that orcas can hear up to 100kHz. The lower jaw of the killer whale also acts as a sound receptor (Diagram C). Killer whales do not have a sense of smell because the olfactory nerves and olfactory lobes of the brain aren’t present. Since they are air breathing mammals that spend most of their time underwater a sense of smell wouldn’t really come to use. (Senses, SeaWorld) Killer whales reproduce sexually. A female killer whale is sexually mature when it reaches fifteen to sixteen feet. Males are sexually mature when they reach eighteen to twenty feet.Baby kil ler whales are called calves. The gestation process for calves is seventeen months. Calves are born throughout the year but mostly during the summer time. Calves are born every five years. A calf weighs around three hundred to four hundred pounds and is approximately eight feet long. (Reproduction and Gestation, WhalesBC). Orcas are very conservative of their young. (Killer Whales, National Geographic). Killer whale are highly active predators. Orcas eat a wide variety of species, such as squids, sea mammals, and fish. These dolphins are one of the top predators in the ocean.Orcas eat a wide variety of fish, like fishes from the surface, such as salmon, to bottom dwelling species, such as halibut. Some orcas feed on marine mammals like walruses, baleen whale, sea lion, seals, and sometimes sea otters. Its common for killer whales to eat varieties of fish and squids , but very rarely they eat sea mammals. Adult Orcas eat about two to four percent of their body weight in food every da y(Food Preferences and Resources, Sea World). That is approximately about one hundred fifty to three hundred pounds of food a day(Killer Whales, MarineBio. Net).Growing calves eat more they eat as much as ten percent of their body weight. Killer whale hunt in groups or â€Å"pods†. A pod is a bunch of individuals moving together as a group. A pod size is different in all areas of the globe. Male, female and calves are often grouped together in pods. Orcas often work together to surround a group of small prey before attacking. When hunting a bigger species such as a whale , the pod of dolphins would attack from several different angles all at once. Orcas are called killer whales because they tend to eat mostly whatever is in their ath. Orcas have very sharp, cone shaped teeth used to rip and tear prey. (Methods of Collecting Food, Sea World). Killer whales use echolocation sound wave to communicate. Echolocation is the location of objects by reflected sounds. This is used in d olphins and bats. This is what the killer whales rely on to hunt in the dark, communicate, and to navigate. Some sounds a killer whale make are jaw claps , echolocation clicks, low-frequency pops, pulsed calls, and whistles . The orca makes this sound by moving the air between the nasal sacs in the blowhole area.Humans have a lot of impact on killer whales. Humans have always been interested in learning abut the killer whale, but not much research could be found on them. The first image of a killer whale was found on a cave drawing in Norway, its about 9000 years old. There are often false myths about killer whales, and many times this misinformation leads to harm for the whales. Killer whales have been often hunted for their meats, organs, and blubber. Before 1981, six thousand killer whales were taken by Japanese , Norwegian, and Soviet whalers. (Human Impact, Sea World).Killer whales have many adaptations like diving, respiration, thermoregulation, and sleep. Orcas are very fast swimmers in the water. They can swim up to twenty eight miles per hour. They usually swim eight miles per hour. Killer whales maneuver well in the ocean. When near the surface the killer whale stays under water for thirty seconds or less. Killer whales are also known for their diving tactics. They can dive one hundred meters in the ocean. Killer whales also use thermoregulation. Thermoregulation is also the process of regulating body temperature.Orcas are very warm blooded their body temperature is similar humans. The large size of a killer whale keeps the whale warm. Under the orcas skin is a very thick layer of blubber which helps protect the amount of heat loss. Killer whales have a high metabolism, which also creates a lot of body heat. The orcas circulatory system assist in keeping the body temperature in place. The arteries contain warm blood from the core of the body and the veins contain cool blood, heat is often transferred from the arteries to the eins (Diagram D shows how this happens). Killer whales have been observed to rest or â€Å"sleep† for short periods of time sometimes as long as eight hours during the night. Calves have been observed to rest for a lesser period of time. (Adaptations, Sea world) Since Killer whales have no predator they could live fifty to eighty years. The only predators killer whale’s have are human (Killer Whales, NOAA). There are many causes to the death of killer whales, one cause is disease. Ulcers, tumors, skin diseases , heart disease, and respiratory issues.Some killer whale have been diagnosed with Hodgkin’s disease, this is a cancer of lymph tissue found in the lymph nodes, spleen, liver, bone marrow, and other sites. Orcas sometimes suffer from several infections. Parasites are another issue causing harm to the killer whales health. Some parasite are flukes, roundworm, and tapeworms. (Longevity and causes of death, Sea world) The killer whale, or orca, is the fastest of the marine mammals; i ts powerful tail flukes help propel it through the water. It is also the largest of all dolphins.Orcas can get very big, it is possible for then to weigh up to six tons. Some orcas grow twenty three to thirty two feet long. They have approximately forty to fifty cone-shaped teeth, that are up to four inches long. Not much is told about their age but some resources show that some killer whales that live in the wild are about thirty to eighty years old. Killer whales have a widely spread population they are found in all parts of the oceans. Orcas have a counter shaded color pattern, they have a solid black top, and a solid white bottom with an oval shaped white spot which is called an â€Å"eyespot† .The dorsal fin for adult male are triangle shapes and can be up to six feet high. On the other hand a female dorsal fin is slightly curved, and that can grow up to three feet high. Orcas are considered to be one of the top predators in the ocean. Killer whales eat a variety of fish , seals, whales, sea lions, squid, and seabirds. Research shows that killer whales are capable of ripping seals of ice. Whales hunt in a group called â€Å"pods†. There are two types of pods residential and transient. Residential prefer to hunt fish and transient prefer to hunt marine mammals.Orcas use echolocation to find food, this technique is also used by bats. Orcas give birth every three to five years in the wild. Females carry their young for seventeen months. Baby orcas or calves are born up to eight feet long and can weight up to four hundred pounds. Orcas are highly protective of their young. These â€Å"pods† communicate with different noises. Killer whales are very intelligent. There has never been a document case on a killer whale attacking a human. (Twenty interesting facts about killer whales, Angela W. LaFon)