Whales. Killer. Why are these whales called killer?
The scientific name of the killer whale is Orcinus orca, which is the source of their other common name, orca. The name "killer whale" causes many misconceptions about this noble beast. First, killer whales are not whales at all. They are, in fact, dolphins (the largest dolphins, actually). Second, they are not particularly violent creatures. Some are hunters, and prey on a variety of creatures, such as squid, shark, otters, sea lions, penguins, birds, octopii, dolphins, and salmon. However, there are no confirmed reports of an orca ever attacking a human being in the wild. This is, perhaps, quite surprising, given how badly the human race has treated them.
Orcas are mammals, like (hopefully) you and me. They do all of the normal mammal stuff like maintain a relatively warm blood temperature, bear their young live, and breathe air. They live together in groups (called pods) that consist of anywhere from two to forty members. These pods are close-knit and last from one
generation to the next.
The killer whale can boast that it is among the fastest swimming marine mammals, traveling at speeds up to 30 miles per hour. Having no desire to gain a reputation for showing off, however, they usually restrict their swimming to a more sedate 2-6 miles per hour. They generally dive 100-200 feet below the surface, and remain there for approximately 4-5 minutes.
The lifespan of the mighty orca is not well known. Reported lifespans range between 25 and 90 years. They typically grow to approximately 20-30 feet in length and weigh 4-8 tons. Females have greater longevity than males, but males are usually larger than females -- although neither one would fit comfortably in your ten gallon aquarium at home.
In fact, many believe that they are not comfortable in captivity at all. In the wild they are able to travel 50-100 miles in a single day. Clearly this is not possible in even the most spacious confines. Further, most captive killer whales are kept alone in relatively uninteresting surroundings. Orcas are relatively intelligent creatures, and they are highly social. They do not survive well out of the wild, dying as much as three times as frequently in captivity as they do in the wild. Given that many of the arguments in favor of captivity are based on the dangers of the wild, this is a disturbing statistic.
Killer whales have no natural predators, although sharks occasionally attack old or weak orcas. Human beings are the only animals that hunt them. These large, powerful creatures are at the top of their food chain. Owing to their great strength and size, as well as their tendency to hunt in groups, orcas are able to hunt
creatures that are much larger than themselves. They have been observed hunting whales, which is the source of the name "killer whale". Originally they were referred to as "whale killers", but the words became reversed at some point. This has led to some bad PR for these poor animals. A prime example of this was the late 1970's horror movie Orca, which tells the heartwarming tale of a bloodthirsty killer whale.
Now you know why these whales are called killer.