Watching whales and orcas is relatively easy off the coast of Iceland in summer. Thousands of tourists participate each year in this type of activity.
What is not so common is to see specimens of these two groups of marine animals swimming together. It should not be forgotten that the diet of killer whales includes various species of whales and dolphins.
The orca known as Sædís and her foster calf make all the difference. To the surprise of tourists, guides and scientists, this female Orcinus orca (scientific name for the misnamed killer whales) was observed in August 2021 and early 2022 maternally accompanying a calf of pilot whale or long-finned pilot whale (Globicephala melas, cetacean of the delphinium family).
The case has been studied by experts from Iceland and Canada, and their results are presented this February in a scientific article published in the Canadian Journal of Zoology.
As the authors point out, "interactions between killer whales and long-finned pilot whales have been documented numerous times, but generally involving predation and persecution events." Now, uniquely, "describes the first documented case of a long-finned pilot whale calf seen in the company (in a staggered position) of an adult female orca, which was part of a group of three orcas, which were in close proximity to several whales. adult pilot".
The team responsible for this research, led by Marie-Thérèse Mrusczok, from the West Iceland Nature Research Center and Orca Guardians Iceland, explains that behavioral, location and photographic data on orcas were recorded and analyzed between 2011 and 2022. , as well as long-finned pilot whales between 2019 and 2022 off western Iceland.
The data was used to obtain background information on the group of killer whales involved in the apparent alloparental behavior (care of a calf by individuals other than the natural parents).
The observations do not allow us to ensure that it is a case of adoption between species, without ruling out that the female orca has taken charge of the pilot whale calf in a way that -seen from a human perspective- could be interpreted as a kidnapping or unwanted capture.
In any case, the authors indicate that "the event described is also presented as the first documented account of the epimeletic behavior of an orca towards a non-conspecific"; that is, the request for care by the young animal from an adult other than its parents, in this case, from a species other than its own.
Movements of the same group of killer whales together with other killer whales during a subsequent interaction with a group of long-finned pilot whales do not fit any observed behavior pattern previously described for interactions between these species and may represent an active effort to obtain a young. of long-finned pilot whale.
"Long-finned pilot whale-orca interactions may be more complex than previously thought and influenced by multiple factors," the authors write.
Marie Mrusczok has detailed that "the orca swam with the pilot whale calf in a staggered position, which means that the calf swam just behind the orca's pectoral fin," according to statements collected by Newsweek.
"The staggered position allows a hatchling to make fewer caudal fin movements than when swimming alone and overcomes physical limitations during high-speed travel; in other words, the hatchling is 'carried' by the pressure wave created by the larger body. adult size".
Elizabeth Zwamborn, co-author of the study, has pointed out, however, that it was not clear if it was an altruistic adoption, according to statements for the Canadian Broadcasting Corporation's Maritime Noon program. We don't know if this case should be interpreted as a "beautiful and warm adoption story" or an orca kidnapping case.
The study indicates that Sædís is not known to have had a calf of his own, so it is possible that he adopted the pilot whale calf as a surrogate.
