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The Independent
19-05-2025
- Science
- The Independent
Icelandic orcas have been including baby pilot whales in their groups – but scientists aren't sure why
An unusual encounter with a group of orcas near Iceland led researchers to discover a new and complex behaviour - they had taken in baby pilot whales, and not necessarily to eat them. Scientists watched two encounters between killer whales and weeks-old baby pilot whales in 2022 and 2023 in a new paper published in Ecology and Evolution, and examined an earlier case in 2021, to come up with three possible reasons for the unusual behaviour. Firstly, it could have been predatory behaviour, but the researchers noted the groups of whales in question largely eat fish only. Another reason was for play, or for hunting training. But the third possible reason could be that the orcas were caring for the calves, and had potentially adopted the pilot whales. But the researchers, led by Cherine Baumgartner, stressed they had not seen the beginning or end of the interactions, and more close observation would be needed to unpick what exactly was happening between the two whale species. Orcas are apex ocean predators, and normally only interact with other species to hunt them, the researchers said. But researchers in 2022 spotted a group of killer whales travelling with a very young pilot whale calf. At times, the researchers notice a killer whale keeping its head very close to the calf's body, 'seemingly nudging the calf towards the surface with the pilot whale calf appearing to respond often with tail slapping'. Then in 2023, a team noticed a different group of killer whales traveling with another very small pilot whale calf, which was repeatedly seen swimming near an adult female in an echelon position, which is a behaviour that has been seen in both aggressive context and more caregiving contexts. The calf was later seen being lifted out of the water by a killer whale. The researchers said while the activity appeared to be 'playful', that doesn't mean play was the main reason for the orcas interacting with the pilot whale calves. A related potential explanation was practice hunting. 'Observations of a female and a juvenile swimming on either side of the pilot whale calf may indicate training exercises aimed at preventing prey from evading,' the researchers said. 'Such coordinated behaviour could serve as practice for herding techniques used during actual feeding, though this remains untested.' The final possible explanation offered by researchers is that the orcas had potentially adopted the pilot whale calves, in what is called epimeletic behaviour or alloparental care. 'During our longer encounters … we observed behaviours that could be interpreted as caregiving, such as pushing the pilot whale calf from underneath - potentially to keep it afloat,' the paper said. But they warned that all three encounters reported to date had been brief - a matter of hours, or less - and probably only showed part of a longer series of events. One of the co-researchers told Scientific American that how the calves ended up with the killer whales to begin with, and what happened to them afterwards, were key questions. 'Was it lost or abandoned?' said Filipa Samarra, from the University of Iceland and the principal investigator at the Icelanding Orca Project. 'Or did the killer whales actively approach to take the calf away?' Another key question is how many different orca groups have done similar things. 'So far, different killer whale groups have been involved in all three events reported, but we do not know how widespread this behaviour is within the population,' they said.
Yahoo
18-05-2025
- Science
- Yahoo
Benevolent Orca Pods Are Adopting Baby Pilot Whales in an Apparent Effort to Clean Up the Species' Image
As so-called "killer whales" have made news over the past few years for violent boat attacks in European waters, marine biologists have noticed a far sweeter behavior in Iceland's frigid waves: the adoption of a baby whale from an entirely different species. In interviews with Scientific American, scientists described their shock at observing a pilot whale calf that traveled with an Icelandic pod of orcas over a period of years. One of those researchers, Chérine Baumgartner, said she and her colleagues at the Icelandic Orca Project initially couldn't believe their eyes. "At first, we were like, 'Oh my god, this killer whale calf has a problem,'" the researcher said of the bulbous-headed baby she and her team first spotted back in 2022. It looked at first glance like a malformed orca — until they realized it was no killer whale at all. The next day, when Baumgartner and her colleagues were witnessing the same pod again, the baby pilot whale was absent. Eventually, however, they started seeing baby pilot whales with orca pods throughout 2022 and 2023, and began to develop theories about what was happening. In a new paper published in the journal Ecology and Evolution, Baumgartner and her team from a consortium of Nordic research institutions have posited three theories about the fascinating matchup: that the orcas are hunting the babies, playing with them, or perhaps even nurturing them. As SciAm notes, each sighting involved a pilot whale calf that could be no more than a few weeks old that swam alongside an adult orca female in what marine biologists call "echelon position," with the baby beside and slightly behind the elder. In some instances, the baby pilot whale was nudged along by the adult orcas, and on another occasion, it swam ahead of the pod before the adults caught up to it and lifted it out of the water and onto one of their backs. That kind of playful and protective behavior does not, of course, sound predatory — but because "killer whales" are known for their violence, it can't be completely ruled out, the scientists say. Along with what the orcas are doing with the baby pilot whales, researchers want to know how the two species, which generally do not overlap, came to not only be in the same place but also coexist in such a way. "It could be," Baumgartner told SciAm, "[that the orcas] encountered the pilot whale opportunistically, and some individuals played with the whale, and others tried to nurture it." As study co-author Filipa Samarra noted, there's a chance that climate change has led pilot whales, which typically follow schools of warm water-seeking mackerel, into orca territory. More on marine life: Scientists Take First Ever Video of Colossal Squid in the Wild... With One Comical Issue
