Surprising behavior in one of the world’s least studied mammals

Some animals live in areas of the globe that are so remote and inaccessible that it is almost impossible to study them in their natural habitat. Beaked whales, of which 24 species have been discovered so far, are one of them: they live far from land and in deep ocean waters, where they search for food at depths of 500 meters and more.

The record holder for the deepest dive by a mammal is a Cuvier’s beaked whale, which in 2014 dove to at least 2,992 meters. A beaked whale also holds the mammal record for longest dive; 222 minutes.

Now the world is getting a new and surprising insight into the world of distant beaked whales thanks to a scientific study of a population of Baird’s beaked whales. The population was unexpectedly discovered near the coast and in shallower waters than previously observed.

The study is led by whale biologists Olga Filatova and Ivan Fedutin from the University of Southern Denmark/Fjord&Bælt, and is published in the journal Animal behavior.

Filatova and Fedutin have many years of studying whales in the North Pacific, and it was during an expedition to the Commander Islands in 2008 that they first sighted a pod of whales. Baird’s bill near the coast.

“We were there to look for killer whales and humpback whales, so we just found that we saw a pod of Baird’s beaked whales and we didn’t do much. But we also saw them the Over the next few years, and after five years, we suspected that this was a stable community frequently visiting the same area.

“We saw them every year until 2020, when COVID-19 prevented us from returning to the Commander Islands,” says Olga Filatova, a whale expert and postdoctoral fellow at the Department of Biology and the SDU Climate Cluster at the University of Southern Denmark.

The studied population of Baird’s beaked whales moved closer to the coast, less than four kilometers from land, and was observed in shallow waters, less than 300 meters.

“This is not characteristic of this species,” explains Olga Filatova, who also points out that the population has probably adapted to this particular habitat and thus deviates from the established perception that all beaked whales roam far in sea ​​and deep waters.

“This means that you cannot expect all individuals of a specific species to behave in the same way. This makes planning for species protection difficult. In this case, for example, you cannot plan based on the assumption that beaked whales only live far away in “We have shown that they can also live in shallow, coastal waters. There may be other different habitats that we don’t know about yet,” says Olga Filatova.

There are many examples of individuals of the same species of whale that do not behave in the same way. In the world of whales, it is common to find groups of the same species living in different places, eating different prey, communicating differently, and not liking to mingle with other species from other groups.

Some groups of killer whales hunt only marine mammals like seals and porpoises, others only herring. Some humpback whales migrate between the tropics and the Arctic; others reside in certain areas. Some groups of sperm whales develop their own dialects for internal communication and do not like to communicate with others outside the group.

According to Olga Filatova, social learning comes into play when groups develop preferences, for example, for habitats and prey.

There are many forms of social learning in the animal world. Imitation is the most complex form; the animal sees what others are doing and understands the motivation and reasoning behind it. Then there is “local enhancement,” where an animal sees another animal heading toward a specific location, follows it, and learns that the location is valuable. This has been observed in many animals, including fish.

Olga Filatova believes that the Baird’s beaked whale population on the Commander Islands is learning through “local improvement.” They see that some of their peers are heading towards the shallow waters near the coast, follow them and discover that it is a good place, probably because there are many fish.

“This is becoming a cultural tradition, and this is the first time a cultural tradition has been observed in beaked whales,” she says.

Other examples of cultural traditions among whales include the development of specific hunting traditions: some strike with their tails to stun fish, some generate waves to wash seals off ice floes, and some hunt fish on the beach.

Researchers observed a total of 186 individuals of the Baird’s beaked whale species on the Commander Islands between 2008 and 2019. 107 were only observed once and were therefore considered to be transient whales. 79 individuals were spotted for more than a year and were thus assessed as residents.

61 of the passing whales were seen interacting with residents, and seven of them were seen in shallow waters.

“Transients are not as familiar with local conditions as residents and, therefore, they generally forage at depths normal for their species. But we have actually observed some transients in shallow areas. It s “These were individuals who presented a certain form of social contact with the inhabitants. It was undoubtedly during this contact that they discovered shallow water and its advantages”, explains Olga Filatova.

It is not known exactly how many Baird’s beaked whales exist in the world.