Killer Whales

Leana Timoteo
Zoology 101 Lab
11/26/12
Killer Whales The killer whales also referred to as the blackfish belongs to the oceanic dolphins family. They are one of the biggest dolphins in the dolphin family. Killer whales can reach up to 9 feet and can weight up to 7,257 pounds. The Spanish call them the Ballena Asesina because they are so powerful and are known for killing other whales and hunting in groups earning the title Wolves of the Sea. They are seen traveling in pods between 3-25 whales. In each pod they all have a strong bond with each other. Killer whales establish dominance and communicated their social order by slapping their tails against the water, jaw snapping, raking, or biting. Like other mammals the killer whale is warm blooded, air breathing mammal. They are the top-level marine carnivores and opportunistic feeders. They prey on dolphins, seals, fishes, sea lions, walruses, penguins, and other whales. Killer whales inhabit all oceans around the world from the coldest to tropical oceans, but mostly found in the Arctic and Antarctica. There have even been sightings in Hawaii and the Bahamas. The killer whales diets varies from what region they are at for example if a killer whale was in the Antarctica it would eat 67% more fish and if it were in the marines then it would eat 27% of fish. Each whale needs to consume about 4% of its body weight each day. Baby killer whales can even eat 10% of their body weight during the growth periods. Studies have shown that female orcas become sexually mature when they are around six to ten years old. Male orcas become sexually mature when they are about ten to thirteen years old. Mating usually occurs in the summer and they usually carry an unborn baby for about seventeen months, which means a female may bear a calf every three to five years. Calves usually are born tails first in the water weighing up to 136-181 kg. Calves develop very quickly because the mother’s milk is very rich making the blubber on the calves very thick. They usually are nursed up to 12 months or more. Killer whales hearing are very sensitive and can respond to tones up to range of about 0.5 to 125 kHz. Their sound reception usually takes place through the lower jaw. Their eyesight is very sensitive too both in the water and out. Killer whales eyes are on each side of the head right behind and above the mouth. The eyes and external ear openings of killer whales are camouflaged and are located near the white false eye spot. The white false eye spot is very important because preys usually attempt to injure a predators eye when trying to escape however the white eye creates and illusion. Killer whales communicate by sounds that are produced by the movement of air between the nasal sacs in the blowhole region. The frequency of sound from killer whales ranges from 0.1 kHz to about 40 kHz. They usually make sounds that sound like grunts, whistles, or squeaks. Day to day killer whales travel, rest, and socialize. Killer whales are very active in and out of water too. A pod of whales have certain calls that even scientist can tell what pod each whale is from. The lifespan of females can average up to 50 years and males can average up to 50 to 60 years. Killer whales have one of the heaviest brains among the marine mammals. The reason killer whales are so important to us is that for one they are very popular to the public. They have become icons of marine biodiversity and are one of the largest top carnivores on the earth today. They are extremely intelligent, long-lived, and social and are very similar to humans. What makes them so fascinating is that they are found over all around the world and have been studied from different people around the world. After researching killer whales I have become very fascinated by them and think they are one of the coolest mammals in the ocean. I knew they were intelligent but did not know great details about them and I think its very important to help protect and preserve them.

Bibliography
“False Killer Whales in Hawaii.” 1 Nov. 2012. 27 Nov 2012. http://www.cascadiaresearch.org/hawaii/Falsekillerwhale.htm
“Killer Whales.” National Marine Mammal Laboratory. 1 Nov. 2012. 27 Nov 2012. http://www.afsc.noaa.gov/nmml/education/cetaceans/killer.php
“Killer Whales.” Wikipedia. 27 Nov. 2012. 27 Nov 2012. http://en.wikipedia.org/wiki/Killer_whale

Bibliography: “False Killer Whales in Hawaii.” 1 Nov. 2012. 27 Nov 2012. http://www.cascadiaresearch.org/hawaii/Falsekillerwhale.htm “Killer Whales.” National Marine Mammal Laboratory. 1 Nov. 2012. 27 Nov 2012. http://www.afsc.noaa.gov/nmml/education/cetaceans/killer.php “Killer Whales.” Wikipedia. 27 Nov. 2012. 27 Nov 2012. http://en.wikipedia.org/wiki/Killer_whale