Despite an extensive overlap in distributional range and trophic niche, a few observations of interactions between killer whales (Orcinus orca) and white sharks (Carcharodon carcharias) are known to occur and have been recorded in South Africa, Australia, and California (Pyle et al., 1999; Best et al., 2010; Jorgensen et al., 2019; Towner et al., 2022; Towner et al., 2023; Bowlby et al., 2023). Documented predation on white sharks, have to date, occurred in sites where juveniles, subadults and adult white sharks aggregate (Kock and Johnson, 2006; White et al., 2019; Tanaka et al., 2021; Towner et al., 2022; Towner et al., 2023; Reeves et al., 2025). However, to date there is little evidence of killer whales targeting juvenile white sharks, with the notable exception of a white shark ~2.5 m total length (TL) (subadult white sharks range from 2.5 m to 3.5 m TL) captured by a killer whale in a white shark aggregation area in Mossel Bay, South Africa (Towner et al., 2024). Toward the warmer edge of their distribution in the eastern Pacific, the white shark has been recorded at Cedros, San Benito, Guadalupe, and the Revillagigedo Islands in the Mexican Pacific, and is occasionally observed along the western coast of the Baja California Peninsula (McCosker and Lea, 1996; Compagno et al., 1997; Santana-Morales et al., 2012; Hoyos-Padilla et al., 2016; Becerril-García et al., 2020; Madigan et al., 2021). White sharks also inhabit the Gulf of California (GC), Mexico where Galván-Magaña et al. (2010) compiled 38 records of white shark captures and reliable sightings from 1964 to 2010, including the presence of juveniles and adults. Most of the records have been obtained from incidental captures during artisanal and industrial fishing activities (Santana-Morales et al., 2012). However, in the last 10 years a potential redistribution of a white shark cohort has been observed in the Northeast Pacific (White et al., 2019; Tanaka et al., 2021), attributed to oceanographic anomalies such as El Niño and the Blob (warm water mass that formed in the Gulf of Alaska and traveled the California current). This redistribution includes an increase in the record of juvenile white sharks in Isla Guadalupe (Santana-Morales et al., 2021) and an increase in the sighting of juvenile and adult white sharks in the GC (pers. comm. Omar Santana-Morales). In the latter area, sightings of killer whales are reported to be frequent year-round (Guerrero-Ruiz et al., 1998, 2007; Niño-Torres et al., 2015) and although there are no historical records of white shark predation by killer whales in the GC, researchers have recently reported predation on different species of rays: Munk’s pigmy devil ray (Mobula munkiana), cownose ray (Rhinoptera steindachneri) and pelagic stingray (Pteroplatytrygon violacea; Higuera-Rivas et al., 2023) and three species of sharks: bull shark (Carcharhinus leucas; Ayres et al., 2024), whale shark (Rhincodon typus; Pancaldi et al., 2024), prickly shark (Echinorhinus cookie; Lara-Lizardi et al., 2025), and unidentified shark (O’Sullivan and Mitchell, 2000; Guerrero-Ruiz et al., 2007). Here we document the first records of interactions between killer whales and juvenile white sharks in Mexican waters.

For each record, we recorded date, time, location, group composition (calves, juveniles, sub adults and adults), traveling mode and any record of feeding behavior. The predation events were documented with a Canon EOS-1D X Mark II DSLR camera and a Canon 100–400 mm lens from a 9 m long fiberglass boat with a 200 Hp 4-stroke outboard motor. Underwater photos and videos were obtained with a second Canon EOS-1D X Mark II camera and a Canon 11–24 mm lens inside a Nauticam underwater housing, and aerial video was recorded using DJI drones, a Phantom 4 Pro and an Inspire 2 X7. High-quality video frame shots of dorsal fins were extracted for photoidentification of individual killer whales using distinctive features, including scars and nicks (Bigg, 1987).

The ecotype of killer whales observed in the GC is not clear; some killer whales have been observed hunting both cetaceans (Guerrero-Ruiz et al., 2007) and chelonians (Esquivel et al., 1993; Sarti et al., 1994), which is consistent with the transient ecotype found off the northwest coast of North America. Other killer whales have been observed hunting elasmobranchs (Guerrero-Ruiz et al., 2007; Higuera-Rivas et al., 2023; Ayres et al., 2024; Pancaldi et al., 2024; Lara-Lizardi et al., 2025), coinciding with a range of known ecotypes such as the offshore ecotype (Heimlich-Boran, 1988; Baird and Dill, 1995; Ford et al., 1998; Dahlheim et al., 2008) and the New Zealand coastal ecotype (Visser, 1999, 2000; Visser and Cooper, 2020), as well as a number of undescribed ecotypes, including those from the Galápagos Islands (Sonnino Sorisio et al., 2006) and from Papua New Guinea (Visser and Bonoccorso, 2003). Although as a species O. orca displays a generalist foraging behavior, local groups or ecotypes of killer whales typically specialize on a small range of available prey (Ford et al., 1998). In the Northeastern Pacific three sympatric ecotypes of O. orca have been described (Residents, Transients and Offshore) which have morphological, social, ecological, feeding, acoustic, geographic distribution and genetic differences (Bigg, 1982; Ford et al., 2000; Morin et al., 2023). An additional overlapping ecotype has also been recognized in the Eastern Tropical Pacific. This ecotype refers to generalist feeders also known to prey on elasmobranchs (Vargas-Bravo et al., 2020).

Predatory behavior of killer whales on sharks has been recorded in detail in the GC, both in bull sharks (Ayres et al., 2024) and whale sharks (Pancaldi et al., 2024). In South Africa, killer whales have been observed using a special hunting technique that involves causing a large tear in the pectoral girdle of sevengill sharks (Notorynchus cepedianus) to access the liver and feed exclusively on this organ (Engelbrecht et al., 2019). They have also been observed hunting and targeting the liver of juvenile great white sharks (Towner et al., 2023, 2024). Our evidence undoubtedly shows consistency in the repeated assaults and strikes, indicating efficient maneuvering ability by the killer whales in attempting to turn the shark upside down (Figures 1a, b), likely to induce tonic immobility and allow uninterrupted access to the organs for consumption (Pancaldi et al., 2024). According to Engelbrecht et al. (2019), the lack of bite marks or injuries anywhere other than the pectoral fins shows a novel and specialized technique of accessing the liver of the shark with minimal handling of each individual. To efficiently hunt potential prey in multiple regions around the world, killer whales use specialized techniques adapted to the target. In the GC, Higuera-Rivas et al. (2023) found that killer whales hunt Munk’s pigmy devil rays by targeting those closest to the edge of the school and grasping them by the wingtip and then repositioning the rays to hold them by the head. When preying on pelagic stingrays, killer whales tail-slap them forcefully several times to stun them and thus avoid being stung by the defensive spine. In two of the three predation events recorded during the present study, killer whales inverted the white sharks, possibly inducing tonic immobility, potentially to avoid bites. The posterior bite force from a 2.5 m white shark can be 3131 N (Wroe et al., 2008) and can severely injure the predator, thwarting the attack. Animal hypnosis or tonic immobility is an induced method to achieve a temporary cataleptic-like condition that can occur from less than one minute to several hours (Gallup, 1974; Páez et al., 2023). During tonic immobility the elasmobranch is in an ‘unnatural’ orientation, which has the effect of altering the usual course of its sensorimotor and emotional interchanges with its environment (Chertok, 1968), making it easier to be manipulated. Prey handling and inducing tonic immobility may be more easily achieved in smaller white sharks compared with larger individuals, thereby also reducing risk of bite injury (Towner et al., 2022). In this case, we observed direct consumption of the liver, as it was observed to be shared among three of the killer whales (Figures 1c, d). Our reports display an indicative of highly selective feeding by these killer whales, as they held the white sharks upside down for several minutes until they grabbed their pectoral fins and then removed and consumed the sharks’ livers, discarding the rest of the carcasses. Furthermore, we demonstrate that the female killer whales photo-identified and referred to as KWM1, KWM2 (see Supplementary Figure 6) were observed in 2018 hunting Munk’s pygmy devil rays and pelagic rays (Higuera-Rivas et al., 2023), while KWM3 (see Supplementary Figure 7) was observed hunting bull sharks between 2022 and 2023 (Ayres et al., 2024). This clearly indicates that these killer whales are related to each other or belong to the same group, renamed by these authors as the “Moctezuma pod” (after the adult male), and is consistent with the analysis by Pancaldi et al., 2024, which demonstrates that this group of killer whales of the GC exhibits adapted hunting techniques depending on the type of elasmobranch they intend to consume. Distinctive nurseries for juvenile white sharks in the eastern Pacific have been identified, which are generally segregated from adult aggregating sites (Klimley, 1985; Oñate-González et al., 2017; Tamburin et al., 2019). However, recent ocean warming has been attributed to range shifts and novel occurrences of juvenile white sharks (Santana-Morales et al., 2021; Tanaka et al., 2021). For instance, a poleward shift in juvenile white shark distribution from southern to central California has been documented in relation to the increased frequency of El Niño events and marine heat waves (Tanaka et al., 2021). The central California region is a key area where white sharks and killer whales interact (Jorgensen et al., 2019). Similarly, the redistribution of the white shark population attributed to such oceanographic anomalies could potentially also lead to increase juvenile white shark occurrences in the GC potentially making them available as a prey source for the killer whales that occur there year-round.

This is the second record of killer whales targeting juvenile white sharks in the world (Towner et al., 2024) and the first in Mexican waters that we are aware of. Adult white sharks exhibit a memory and previous knowledge about killer whales, which enables them to activate an avoidance mechanism through behavioral risk effects; a ‘fear’- induced mass exodus from aggregations sites (Jorgensen et al., 2019; Towner et al., 2022). This response may preclude repeated successful predation on adult white sharks by killer whales. Considering the naturally small regional population sizes of white sharks (Kanive et al., 2021), this predator evasion mechanism likely prevents significant population depletion through predation. Furthermore, given their natal philopatry (Jorgensen et al., 2010), and a reproductive cycle greater than 12 months (Mollet et al., 2000), female white sharks would likely continue to pup in the same locations, unaware of any recent killer whale predation activity. As a result, juvenile white sharks could be more susceptible to consistent exploitation in juvenile aggregation sites.

In this study we observed repeated predation on juvenile white sharks at the same location and nearly the same calendars date, two years apart. Taken together, this suggests that juvenile white sharks may be becoming, or already are, a regular seasonal prey target for these mammals. Since no photographic identification images were taken of the killer whales in the second report, it is unknown whether they are related or associated with the pod from the first report. While C. carcharias already faces several threats, such as bycatch and climate change, its natural predation by killer whales might represent a significant additional pressure on the white shark populations, as seen in South Africa, where entire coastal displacements and subsequent ecological changes have heated scientific debates (Bowlby et al., 2023; Gennari et al., 2024; Bowlby et al., 2024). Future studies should 1) continue to monitor the shifting ranges and aggregation sites of juvenile white sharks driven by ocean warming, 2) test whether behavioral risk effects occur in juvenile white sharks, and 3) determine whether attacks on white sharks by killer whales represent an emerging pattern and, if not, establish the frequency of these events, as additional observations could make population-level inferences.