Killer whales along the South African coast have been killing great white sharks and stripping out a single organ: the liver. Peer-reviewed research documented this behavior at Mossel Bay, South Africa, where orcas attacked a white shark and left the rest of the carcass largely intact after removing the liver. The predation triggered a multi-week disappearance of white sharks from the area, and similar liver-focused kills have now been recorded in waters off California and Mexico’s Gulf of California, raising questions about how far this hunting strategy will spread and what it means for white shark populations worldwide.
Why liver-targeted kills are reshaping shark ecology
The immediate consequence of these attacks goes well beyond the loss of individual sharks. When orcas kill even one white shark at a given site, the remaining sharks flee and stay away for weeks. A peer-reviewed study documented this flight response at Mossel Bay, where white shark sightings dropped to zero for an extended period after a single predation event. That absence ripples through the food web: with apex predators gone, prey species like Cape fur seals experience reduced predation pressure, altering the balance of the local marine ecosystem.
Research published in Scientific Reports confirmed that killer whale presence alone can measurably shift white shark hunting pressure on seals. The sharks do not simply move to a different part of the same bay. They vacate entire regions, sometimes for weeks at a time. For coastal ecosystems that depend on the top-down control white sharks exert, even temporary absences can produce cascading effects on seal colonies, fish populations, and the broader marine community.
The hypothesis that this behavior will expand to new white shark aggregation sites within a few years is grounded in the geographic pattern already visible in the data. Liver-targeting predation has been recorded across three distinct regions: South Africa, California, and Mexico. If orca pods that have learned this technique continue to encounter white sharks at other known gathering points, the same cycle of kills followed by prolonged shark flight could repeat, producing site-specific drops in shark residency that go beyond the temporary responses already measured.
Cross-ocean evidence of surgical organ extraction
The South African cases drew the most public attention, partly because carcasses washing ashore with missing livers provided visceral physical evidence. Reporting tied to the peer-reviewed literature described broader patterns of missing great whites in South Africa, with researchers combining data from electronic tags, drone surveys, and shark-tour operator observations to build the case that orcas were responsible. The liver-only extraction pattern was consistent across multiple carcasses, ruling out scavenging or incidental damage.
Additional coverage in independent reporting emphasized how quickly local shark tourism operations felt the impact, as sightings declined in step with the new predation pressure. Operators who once relied on predictable shark aggregations near seal colonies reported abrupt changes in shark behavior and residency, reinforcing the ecological signals seen in formal tagging and survey datasets.
But the behavior is not confined to one ocean. A 1999 study published in Marine Mammal Science documented a killer whale predation event on a white shark off California in which the orcas selectively consumed lipid-rich organs and discarded muscle tissue. That account, recorded years before the South African cases gained wide attention, established an early scientific precedent showing that orcas can and do target the most energy-dense parts of a white shark’s body.
The most recent addition to this evidence base comes from Mexico’s Gulf of California, where a peer-reviewed study published in Frontiers in Marine Science documented orcas interacting with juvenile white sharks. Researchers observed behaviors consistent with immobilization and organ consumption, extending the geographic footprint of liver-focused predation well beyond South Africa. The study’s authors concluded that this pattern is not a single-site anomaly but a recurring behavioral strategy.
Liver tissue is energetically valuable to orcas because shark livers are enormous relative to body size and packed with oil-rich squalene. A great white’s liver can account for a substantial fraction of its total body weight, and the caloric density of that organ far exceeds what an orca would gain from consuming the same mass of shark muscle. This explains the surgical precision: the orcas are maximizing caloric return per kill, a strategy that makes ecological sense for a large, warm-blooded predator that burns significant energy during hunts.
Gaps in tracking and the next sites to watch
Several key questions remain unanswered. No primary dataset published so far quantifies the exact liver mass or caloric yield from the specific white sharks killed in South Africa or Mexico. Without those numbers, researchers cannot calculate the precise energy budget that makes liver extraction worthwhile compared to consuming the entire shark. Official stranding or fisheries records confirming the total number of liver-only carcasses across all reported sites also remain unavailable in the published literature, making it difficult to estimate how frequently these kills occur versus how often they simply go undetected.
Perhaps the most significant gap involves individual orca identification. Long-term tagging data directly linking specific orca pods to repeated liver extractions at multiple locations have not yet appeared in published primary sources. Without that tracking, scientists cannot determine whether the behavior is spreading between orca groups through social learning or whether it is emerging independently in different populations that face similar ecological conditions. Photographic catalogs and dorsal fin IDs used in other killer whale studies could help, but they have not yet produced a definitive map of which pods are responsible for the known kills.
Those uncertainties make it harder to forecast exactly which white shark aggregation sites are most at risk. However, the pattern so far suggests that predictable seasonal hotspots-such as areas near seal rookeries or migratory bottlenecks-are the logical next candidates. If orcas that already specialize in marine mammals begin to experiment more frequently with sharks in these locations, even a handful of successful liver-focused hunts could be enough to drive sharks away for extended periods, as seen at Mossel Bay.
For managers and researchers, that possibility raises practical questions. Long-term acoustic receiver arrays and satellite tagging programs designed to monitor shark movements may need to be expanded or reconfigured to capture rapid, predator-driven displacement events. At the same time, conservation strategies built around the assumption that white shark distributions are relatively stable from year to year may need to account for sudden, behaviorally induced absences that are not driven by fishing or climate but by another apex predator.
There are also implications for tourism and coastal economies that have come to depend on reliable shark sightings. Cage-diving operators in South Africa have already experienced multi-year downturns in white shark encounters coinciding with the rise of orca predation. If similar dynamics emerge in California or Mexico, local businesses may face the same uncertainty, with knock-on effects for public perception of shark conservation and for funding of research programs that rely on tourism partnerships.
Ultimately, the emerging picture is of a flexible, intelligent predator exploiting a rich new food source in a way that reshapes entire coastal ecosystems. Killer whales have long been known to develop specialized hunting cultures, from seal-washing techniques in Patagonia to fish-herding strategies in the North Pacific. Liver-targeted attacks on great white sharks appear to be another such innovation, one that could spread as orcas encounter more sharks at predictable aggregation sites.
Whether white sharks can adapt remains unclear. They may alter their migration timing, avoid historically important feeding grounds, or shift hunting strategies in response to the new threat. For now, the evidence from South Africa, California, and the Gulf of California shows that a single behavioral shift by a top predator can reverberate across oceans, forcing scientists to rethink long-held assumptions about who sits at the very top of the marine food web.
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*This article was researched with the help of AI, with human editors creating the final content.
