I had the unique experience of working with a killer whale orphan. Her mother was dead and she had ended up swimming into Puget Sound. She was about three years old and a little over 1, pounds. We went out and did health assessments on her every week. We tried collecting various types of data and soon veterinarians were saying we needed a blood sample—we thought we'd done well enough getting a breath sample.
So we basically had to develop a bond with the animal in terms of socializing with it. But we were warned by one of the veterinarians at SeaWorld that you had to be extremely cautious going down that road with the animal.
In order to make sure she didn't freak out during the sampling we did a bit of scratching her [with a scratching stick and our hands].
She then started rubbing on the bottom of the boat , so we had started on that slippery slope. They do want to bond. Obviously they're programmed to bond with members of their own species, but they can form a bond with other animals like humans.
It was a year-old male killer whale that was involved in the attack. Is 30 old for a killer whale? In many ways their life spans are sort of like ours. In the wild we have some females that are thought to be in their 80s and one male thought to be in his 50s. But most males tend to live into their 30s. Right now we're working off 30 years of data, which may sound like a lot, but when you're studying such long-living animals it isn't that much.
We don't know if males we follow are dying at a relatively young age. Do you think the age or gender might have played a role in this animal's behavior? In resident-type whales, they're basically matriarchal societies, where the females are the center of the social structures. Up until puberty, males and females look pretty much alike, but at 15 years of age they sprout—and what we mean by that is their dorsal fins start to grow. Besides being larger in body size the males are very distinctively different looking animals.
But is it for male—male competition or female selection? We don't know. But it may alter the way they or other animals relate to them.
How do these whales feed in the wild? These animals will share their prey. We were doing a focal follow where we would pick an individual and follow in its food tracks, and one of the other whales would swim over and join up with it.
The orca seemed to pull out of the attack just before making contact. The Norwegian Orca Survey said in a Facebook post that the orca likely realized the surfer was not a seal at the very last second. In , a year-old boy was "bumped" by a killer whale near Ketchikan, Alaska, in what may have been an aborted attack — similar to the surfer in Norway — or simply curiosity on behalf of the orca, according to the Associated Press, via The Seattle Times.
The Associated Press reported that a surfer was bitten in California in the early s, which is the only relatively well-documented case of a wild orca actually biting a human. Orcas in captivity, however, have attacked and killed people. Although wild killer whales do not intentionally harm people, they have attacked boats. There were many reports beginning in the summer of of orcas ramming into and causing damage to sailing boats off the coast of Spain and Portugal, according to BBC News.
Three juvenile male orcas were involved in most of the attacks, and marine biologists investigating the incidents believe that the young males were playing with the boats by targeting the rudders and pushing the boats around.
Orcas are very social creatures and live in family groups called pods, which have up to 50 members, according to the University of Michigan's Animal Diversity Web ADW.
These pods are made up of related mothers and their descendants, known as matrilines. A male orca will stay with its mother for life, while daughters may spend time away after having calves of their own, according to the wildlife charity Whale and Dolphin Conservation WDC. Pods often have their own distinctive calls, or dialects, to communicate, but they will associate with other pods and can come together to form even larger, temporary groups. A female killer whale will give birth to one offspring at a time every three to 10 years.
The gestation period usually lasts for around 17 months according to SeaWorld. Orcas work together to take care of the young, and other females in the pod will often help with the rearing. Female killer whales have an average life span of 50 years, but some individuals are estimated to have lived up to years.
Males live shorter lives, with an average life span of 29 years and a maximum life span of 60 years, according to the Center for Whale Research in Washington state.
Killer whales are the most widely distributed mammals, other than humans and possibly brown rats, according to SeaWorld. They live in every ocean around the world and have adapted to different climates, from the warm waters near the equator to the icy waters of the North and South Pole regions. Orcas have been known to travel long distances. For example, one study found that a group of orcas traveled from the waters off of Alaska to those near central California, according to IUCN — a distance of more than 1, miles 1, km.
All orcas are currently listed under one species, Orcinus orca. However, there are recognizable differences between populations, and biologists have identified several distinct forms, known as ecotypes, which may actually be different species or subspecies, according to the National Oceanic and Atmospheric Administration NOAA. Killer whale ecotypes can vary in size, diet and behavior.
In the North Pacific, scientists have identified resident orcas, which tend to have small ranges — hence the name — and specialize in catching fish. They have evolved to swim up to 40 miles a day, foraging for food and exercising.
They dive to feet, several times a day, every day. Whether they're born in the wild or in captivity, all orcas born have the same innate drive to swim far and dive deep. Artificial enclosures in captivity cannon offer that kind of range to orcas, contributing to boredom and stress.
Orcas have been seen to develop stereotypies, also known as zoochosis—repetitive patterns of activity that have no obvious function, which range from self-mutilation to rocking and swaying. Usually related to stress and inappropriate habitats, stereotypic behavior has been documented in orcas in scientific research since the late s. In the wild, orcas live in tight-knit family groups that share a sophisticated, unique culture that is passed down through generations, research has shown.
In captivity, orcas are kept in artificial social groups. Captive-born orcas are often transferred between facilities, breaking up social relationships.
In , the documentary film Blackfish laid bare the psychological toll of captivity, through the story of a wild-caught orca named Tilikum who had killed two trainers at SeaWorld Orlando. All rights reserved. Orcas are highly intelligent, social mammals. Common Name: Orca Killer Whale. Scientific Name: Orcinus orca. Type: Mammals. Diet: Carnivore. Group Name: Pod. Size: 23 to 32 feet. Weight: Up to 6 tons. Size relative to a bus:. Data deficient.
Least Concern Extinct. Current Population Trend: Unknown.
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