Orcas, also known as killer whales, stand firmly at the top of the marine food chain, a position they maintain through remarkable intelligence and coordinated hunting. While many people recognize their predatory skill against seals and other whales, the question of whether they hunt sharks, even the formidable Great White Shark, is met with less certainty. The answer is definitively yes: orcas are one of the ocean’s few predators capable of hunting and consuming large shark species. This behavior involves sophisticated tactics that demonstrate the killer whale’s status as the true apex predator of the sea.
Documented Shark Predation
Evidence of orcas preying on sharks is documented across various global locations and species. Targeted prey include the Great White Shark, Blue Sharks, Pacific Sleeper Sharks, and Shortfin Mako Sharks. Observations span from the waters off South Africa, where two known orcas have caused a mass exodus of Great Whites, to the Gulf of California and the coast of California, USA.
Confirmed predation events are identified through direct observation, sometimes captured by drone footage, or by examining shark carcasses that wash ashore. These carcasses frequently show a precise wound and the absence of the liver, indicating a highly targeted attack. The Offshore ecotype of orca has been documented to have a diet where elasmobranchs—sharks and rays—make up nearly 90% of their prey. This pattern points to a specialized hunting strategy against cartilaginous fish.
Specialized Hunting Strategy
Successful predation of a shark, particularly a large species like a Great White, requires a coordinated strategy to neutralize the prey’s defenses. Orcas typically hunt in pods, using their collective size and speed to isolate and control the shark. The primary tactic involves inducing a temporary state called tonic immobility, which paralyzes the shark.
To achieve this, orcas work together to ram the shark and push it to the surface, flipping it completely upside down. In this inverted position, the shark’s sensory system is overwhelmed, leading to a docile, defenseless state that can last for several minutes. This technique minimizes the risk of injury to the orcas from the shark’s movements. Once the shark is immobilized, the orcas safely access the body cavity to remove internal organs.
The Nutritional Value of Shark Liver
The motivation behind this precise hunting method is the nutritional value of the shark’s liver. In many shark species, the liver is disproportionately large, sometimes accounting for up to 25% of the animal’s total body weight. This organ is rich in fat and oil, containing high concentrations of a lipid compound called squalene.
Orcas require significant energy to sustain their large bodies and active lifestyle. The squalene-rich liver provides a concentrated, high-caloric fuel source. By selectively consuming only the liver, orcas maximize their caloric intake while minimizing the effort required to process the carcass. This targeted feeding explains why researchers often find shark bodies with a precise wound near the pectoral fins, where the orcas extracted the energy-dense organ.
Orca Ecotypes and Feeding Specialization
Shark predation is not a universal behavior across all orca populations, but a specialized skill developed by specific groups, known as ecotypes. In the Northeastern Pacific, three main ecotypes exist: Residents, who primarily eat fish; Transients (or Bigg’s orcas), who hunt marine mammals; and Offshores. The Offshore ecotype is most strongly associated with a diet of elasmobranchs, including various shark and ray species.
This specialized hunting behavior is a form of cultural learning, passed down through generations within a pod. For example, a pod in the Gulf of California has developed a specialized strategy for hunting juvenile Great Whites. This specialization highlights that orca behavior is adaptable and transmitted socially, leading to distinct regional feeding preferences and hunting techniques.