Orcas, otherwise known as killer whales, are the largest member of the dolphin family and are one of the most powerful predators in the ocean. They make a wide variety of communicative noises that differ between pods. The pod members can recognize these noises from miles away so they don't get lost. Orcas have also perfected the use of echolocation. They send clicks underwater and use those clicks to sense if there is a school of fish or an object nearby. They wait for the vibration from the clicks they send to bounce off whatever they are looking for and if they receive the right vibration they will swim to wherever it came from. These vibrations reveal the object's size, shape, and location.
Though they can frequently be found in coastal waters, orcas can also be found from polar regions to the equator. Their diet is incredibly diverse and consists of small fish, penguins, seals, sea lions, squid, sea birds, and even sometimes whales. Orcas hunt in pods with up to fourty members. There are two types of pods, resident pods and transit pods. Resident pods tend to stay in the same areas whereas transit pods don’t have one designated area that they stay in, they just roam wherever they can find food. Resident pods prefer eating fish whereas transit pods prefer eating marine mammals. Regardless of the pod type they all use cooperative tactics to hunt for prey.
Orcas are extremely protective of their young, other females in the pod will often help another mother take care of her baby. Female orcas only give birth every three to ten years and their pregnancies last for seventeen months. They are only able to have calves for the first twenty five years after they reach maturity. They take care of their baby for up to two years and after that the baby will often go off with another pod. On rare occasions the baby will stay with the pod they were born in for their whole life. The average life span for male orcas is thirty whereas females live to about sixty. There have been some females known to live until their nineties.
Orcas are social and highly intelligent animals that have been involved in marine park entertainment for decades, but recent studies show that they do not thrive in captivity. They evolved to swim forty miles per day while foraging for food and exercise. They can dive one hundred to five hundred feet down multiple times per day. Regardless of being in the wild or being held in captivity all orcas have the natural instinct to want to dive deep. Orca enclosures, no matter the size, can not simulate the range of an open ocean. This leads to the orcas becoming stressed and bored. Being held in captivity can make orcas develop zoochosis. Zoochosis is when captive animals become overly stressed, depressed, and confused because they are not in a familiar environment or they feel trapped. These repetitive patterns of activity have no real purpose. These patterns can range from self mutilation to rocking and swaying. Zoochosis has been documented in captive orcas since the 1980s. In the wild, orcas live in tight knit family groups. These groups share a unique culture and way of communication that gets passed down through generations. Research shows that captive orcas are kept in fake family groups and are often transferred from facility to facility which breaks up social relationships. The stress of social ail disruption can make orcas become depressed. That is why so many people feel so strongly about banning places such as Sea World from using orcas as a form of entertainment.
Orcas face increase threats as the oceans become more polluted. In 2005 orcas living in Puget Sound were listed as endangered under the US endangered species act. Scientists believe their population numbers could also be going down due to the decreasing number of salmon because it is one of their main food sources. Pollution, climate change, and boat noises could be some other factors in the orca’s disappearance , and unless dramatic steps are taken, they will continue to die out. If you want to learn about what you can do to help save marine life check out some other articles on the Beachlex page!
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