Orcas Around Crozet Islands Teach Each Other to Raid Fisheries

Killer whales, also known as orcas, are considered to be the ocean's top predators. Aside from their predatory activities, a new study suggests that these animals have another interest in mind.

Images taken from 2010 to 2017 in the Crozet Islands revealed that killer whales raid fisheries around the region and their group members are increasing through time.

Killer Whale Raids Southern Indian Ocean

(Photo : Messina Photo from Pexels)

Research led by experts from the Deakin University said that orcas have other focus on their daily lives aside from simply attacking their potential food. These marine mammals have teaching traits, providing the necessary skills to steal fish from fishery remains.

The study, which mostly revolved around the region near the southern Indian Ocean, was carried out between 2010 to 2017. It followed a group of orcas in the Crozet Islands.

The killer whales, according to the records, were observed to feed themselves by stealing their food from a lot of fisheries across the region. Among their favorites are the Patagonian toothfish.

The research was conducted by experts from Australia's Deakin University with the School of Life and Environmental Sciences' Morgane Amelot as lead researcher. According to the authors, numerous fisheries enable feeding opportunities for many marine animals, especially the larger predators, in the form of leftover produce and discarded catch.

The coasts of Crozet Islands are known to house several killers whales who are fond of eating Patagonian toothfish. The case revolving around orcas stealing fish is not new. Previous studies have already identified several raids initiated by the aquatic mammalian in the past years, and it is increasing at an alarming rate.

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Orca Raid Members in Crozet Islands Increasing

The reason killer whales resorted to such unusual activities has remained a mystery. Theories about their assaults are divided by whether it was a product of their migration throughout the seas or simply a common trait that has already existed in the archipelago's original killer whale residents.

To identify the factors that push the mammalians to steal fish, the study analyzed the feeding behaviors extracted from two large populations of subantarctic killer whales. DailyMail reported that each of the groups was categorized as "regular" and "Type D." They learned that there were new orca visitors around the region and the group of killer whales teaches them to initiate the raids.

Seventeen of the killer whales were common suspects of the fisheries raids back in 2010. In 2017, the number increased to 43. The orcas somehow pass the skills to the other members of the group, increasing the number of stealing incidents.

The study was published in Biology Letters, titled "Increasing numbers of killer whale individuals use fisheries as feeding opportunities within subantarctic populations."