An orca has been captured in group attacks on whale sharks on three occasions in the Gulf of California. Given the advanced intelligence of orcas, the authors of the study in which the observations are described suggest that this specimen called Moctezuma, as well as other members of its pod, have acquired – or developed – the necessary knowledge to strategically hunt the biggest fish in the world.
Orcas are the top predators of the sea. They are excellent swimmers, have advanced hunting skills, work as a team, and can communicate their knowledge and techniques across generations. They usually feed on mammals, turtles and fish. While observations are rare, evidence shows that large fish and whales are also part of their diet.
Montezuma’s pack shows strategic behavior
In a recent research published in Frontiers in Marine Scienceresearchers led by Francesca Pancaldi describe four attacks that groups of orcas carried out in a coordinated manner against whale sharks in the Gulf of California, Mexico. The attacks occurred between 2018 and 2024 and have a similar structure. Moctezuma participated in three of these attacks, and in the fourth, orcas participated that have been captured with him on other occasions. “We suggest the possible existence of a specialized pod of elasmobranch-hunting orcas. [clase de peces a la que pertenecen los tiburones] in the Gulf of California,” says the investigation.
The strategy shown in all four attacks is similar. “The killer whales displayed cooperative and coordinated hunting behavior that included repeatedly striking the whale shark at high speed to stun and immobilize it, manipulating and positioning the shark with the ventral side up, and biting the shark on the exposed ventral region, to bleed it to death. through the cloaca and allow access to the organs for consumption.” The organ most sought after by orcas would be the liver, according to the hypothesis presented by the researchers. “The importance of shark liver for the killer whale diet is related to its high caloric content, as its consumption has been suggested to provide additional energy benefits.”
The photos and videos on which the research is based were captured by scientists, but also by the non-specialized public. “In recent years, the advancement of technology, affordability and access to cameras that can record in high resolution have also helped to obtain better captures during these opportunistic sightings, which is particularly important for photo-identification,” say the researchers. .
Montezuma was first identified in 1992. Scientists use recordings of dorsal fins, spots and scars to identify whales over time.
As records of attacks on whale sharks by killer whales are not common, this descriptive research is very valuable.
Whale sharks can grow up to 18 meters long and weigh 20 tons. They only feed on plankton and small fish. Biologists think they are especially vulnerable while they are young.
Leave the orcas alone
Experts have pointed out on multiple occasions the need to regulate and manage marine tourism in the Gulf of California and other sanctuaries to ensure that visits to orca territory are respectful and sustainable.
“It’s not that they are aggressive towards human beings. Their attacks are probably reacting to the bad experiences they have had with the boats,” said Francisco Gómez Díaz, founder and director of the Museum of Whale and Marine Sciences in Baja California, Mexico, in an interview for WIRED en Español in 2023. when Orca attacks against boats were recorded in the Strait of Gibraltar. “There is no record to date of them harming a human being. “They go directly towards the boats.”
“Harassment is one of the main stressors for orcas. There are a large number of boats in the water. We are also exploiting them for ecotourism. We are putting too much pressure on them, we are not letting them live their lives in peace. It is the ocean’s top predator! “There has to be a lot of respect on our part,” he said.
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