Scientists have filmed orcas hunting a dolphin for the first time

The unique footage was captured by a drone off the coast of Chile in 2023. However, for the first time this discovery is described in a study published in the journal Frontiers in Marine Science last week.

Previously, people have repeatedly observed orcas eating dolphin carcasses, but the hunting process itself has never been documented by scientists. Usually only the aftermath of their attacks has been recorded.

The waters off the coast of Chile, rich in krill and anchovies thanks to the Humboldt Current system, are home to a mysterious and little-studied population of killer whales. Thanks to citizen science and years of observation, a team of scientists led by Dr Ana García Segarra from the University of Antofagasta has begun to uncover their secrets, starting with a study of their diet.

Orcas are divided into different ecotypes depending on their diet, acoustic cues and genetics.

In the southern hemisphere, there are five ecotypes: some, such as Type A and Type B1, specialise in hunting marine mammals, while others prefer fish. New data suggest that Chilean killer whales may belong to the Type A ecotype, given their dolphin hunting and small pack sizes.

Observations have shown that the pack, known as the Menacho group, divides prey among members. This behaviour is characteristic of Type A killer whales, which often share food with relatives. Females feed closer members of the group first, indicating a complex social structure.

Dr Garcia Segarra stressed the need for further research and the collection of genetic data to accurately determine the ecotype of Chilean killer whales. However, sample collection is complicated by the secretiveness and intelligence of these animals. Observations of newborn calves are important because they indicate that the population is reproducing, but the survival rate is still unknown.