Orcas Expertly Target Young Great White Sharks in Gulf of California

A specialized pod of orcas, known as Moctezuma’s pod, has been observed in the Gulf of California engaging in a remarkable hunting behavior targeting young great white sharks. These orcas were captured on camera flipping the sharks upside down in a technique that allows them to access the nutrient-rich liver, demonstrating their advanced hunting skills.

The findings, published in the journal Frontiers in Marine Science, suggest that the changing climate and warming waters may be influencing the distribution of great white sharks in the region, presenting new opportunities for orca predation. Marine biologist Erick Higuera Rivas, the project director at Conexiones Terramar and Pelagic Life, asserts that orcas possess the capability to target great white sharks anywhere they inhabit, showcasing their intelligence and strategic hunting methods.

Observations of Hunting Technique

During routine monitoring, researchers documented two separate hunts in which Moctezuma’s pod successfully killed three juvenile great white sharks. In the first hunt, observed in August 2020, five orcas were seen working collaboratively to turn a juvenile shark upside down, ultimately extracting its liver.

In a similar event in August 2022, the pod employed the same tactic, pushing a juvenile shark onto its back and then consuming its liver while the shark was incapacitated due to a state known as tonic immobility. This state, induced by flipping the shark, temporarily renders it defenseless, allowing the orcas to feed effectively.

“This is the first time we are seeing orcas repeatedly target juvenile white sharks,” said Dr. Salvador Jorgensen from California State University, highlighting the unique nature of these interactions.

While adult great white sharks tend to vacate the area quickly when threatened by orcas, juvenile sharks may lack the experience to evade these sophisticated predators. This raises questions about the learning process involved in anti-predator responses among different shark age classes.

Impact of Climate Change on Shark Populations

Changes in the distribution of white shark populations, partly due to climate events like El Niño, have likely increased their presence in the Gulf of California, making them more vulnerable to predation by orcas. Each new cohort of juvenile sharks could represent a seasonal target for Moctezuma’s pod.

The researchers plan to conduct a more comprehensive survey of the orca population’s diet to determine whether hunting juvenile white sharks is a regular behavior or a seasonal adaptation. Dr. Francesca Pancaldi from the Instituto Politécnico Nacional Centro Interdisciplinario de Ciencias Marinas emphasized the need for further investigation to understand these interactions better.

Fieldwork in this area presents challenges due to the unpredictability of orca hunts and the costs associated with research. Nonetheless, the information gathered about the foraging behavior of these killer whales will be crucial for identifying their critical habitats and potentially establishing protected areas to mitigate human impact.

The study’s insights into the hunting strategies of Moctezuma’s pod not only highlight the complexity of predator-prey dynamics but also underscore the need for ongoing research as environmental conditions continue to change in the oceans.