Researchers have determined that killer whale groups form “superpods” to create and maintain social bonds with other whales.
Just like people, killer whales (Orcinus orca) get together to maintain social ties. Although the whales usually live in small pods of 20 or so, they also go in search of other pods, forming aggregate groups of approximately 100. These aquatic gatherings last from a few hours to nearly half a day, according to BBC Earth News.
Scientists from the Far East Russia Orca project observed the killer whales engaging in social behaviors with other pods, such as synchronized swimming and “rubbing flippers”, while in these larger groups. They also noticed that the whales’ sexual activity increased while in the “superpods” – indicating that these gatherings give the whales an opportunities to check out potential mates. Pairing with a whale from another pod likely increases genetic diversity throughout the whale population.
As the whales were rarely foraging while in the large groups, the researchers said that these gatherings were not for hunting purposes, and that feeding in such large groups might even make it more difficult for an individual whale to find food. And, since killer whales have no natural predators, the groups are probably not formed for protection.
Studying killer whale “social clubs”
While the gathering behavior has been seen before, it had never been quantified as “social behavior.” For this study, fish-eating killer whales off the coast of Russia in the Avacha Gulf were observed and photographed by Olga Filatova of the Moscow State University and colleagues from the Far East Russia Orca project.
Because the whale vocalizations of each pod has a specific vocal dialect, and each whale within the pod can be identified by its markings and dorsal fin shape, researchers were able to analyze the whales’ behavior once they joined a superpod. Erich Hoyt, project co-director of the Whale and Dolphin Conservation Society (WDCS) explains that the gatherings are opportunities for the whales to create and maintain social bonds with other whales outside of their own small pod.
The superpods are like big social clubs. These clubs could help them stay acquainted, could be part of the courting process but could have other functions that we need to learn about.
Additional killer whale studies planned
Killer whales have a long lifespan (usually around 40, but up to 90 years! ), but the calf mortality rate is high. Nearly 50% of killer whale calves do not live past their first six months. These factors, combined with life in a small groups, make it even more important for killer whales to connect with other communities. Erich Hoyt believes that studying the social behavior of these highly intelligent mammals will help scientists protect them.
Understanding more about their social lives, including their reproduction, will be crucial to our future understanding of them and our ability to keep their population healthy.
Killer whale superpods have also been seen in British Columbia, Alaska, Iceland and Antarctica. Additional studies, including mammal-eating killer whales, are planned for killer whale groups further north and south along the Kamchatka coast and to the offshore Commander Islands.
Image source: http://www.flickr.com/photos/cmichel67/ / CC BY 2.0
About Rhishja Cota-Larson
i love this pic
this is really interesting since i study killer whales of the coast of bc myself.
Cool eh, we used to see the local pod every year when we lived in Campbell River, BC Canada.
They say that the empathy and social part of their brains are more advanced than ours is. Its so cool how they connect and bond.