Feeding ecology explains what whales and dolphins eat, where they feed, and how prey shapes where they go. Diet tracks ocean productivity — where currents bring nutrients up, prey gathers, and cetaceans follow. Studying this reveals how these predators fit into the Galápagos food web and helps identify critical feeding habitats, inform fisheries management, and predict how a changing ocean affects predators and prey alike.
We study where cetaceans feed, what they eat, how they hunt, and how it all connects to the currents that fuel the Galápagos food web.
We examine how different species use coastal and offshore habitats across the archipelago.
Investigate diet, prey selection, and feeding strategies.
Understand how cetaceans interact with other marine species and contribute to healthy ocean ecosystems
How the Humboldt, Panama, and Cromwell currents create the upwelling that feeds the whole system.
What an animal eats, and where it has to go to find that food, determines almost everything else about it — how far it travels, how healthy it is, and how exposed it is to threats like fishing gear or a changing ocean. Feeding ecology is one of the clearest windows into both individual health and the wider condition of the Galápagos marine ecosystem.
Guides, fishers, and tourists report encounters with photos, GPS locations, and behaviour notes — the main source of feeding data, since dedicated surveys are rare.
Researchers record predation sequence, duration, and location as it happens
Photos and videos of predator-prey interactions are compiled from contributors across countries into one verified dataset.
Sighting locations and behaviour notes are mapped to reveal where feeding activity concentrates.
Note: stable isotope and fatty acid analysis have been proposed as future tools for describing diet, but have not yet been applied in Galápagos killer whale studies.
Galápagos killer whales are opportunistic, generalist feeders. Documented prey includes fish, sharks and rays, sea turtles, sea lions, and other whales and dolphins (Denkinger et al., 2020)
Killer whale hunting technique is consistent across events: head-butting, biting the ventral/caudal regions, and submerging prey.
A global dataset links killer whales to at least 18 elasmobranch species, most often cookiecutter sharks, requiem sharks, and mobula rays.
Whale sharks — confirmed predation off Coiba, Panama and Machalilla, Ecuador, with photo-ID links to the Galápagos population (Orellana-Vásquez et al., 2025).
Bryde's whales — documented attacks within the Galápagos Islands (Alava et al., 2013).
Galápagos sharks (Carcharhinus galapagensis) — recorded as prey in the region (Fertl et al., 1996).
Krill (Nictophanes simplex) — the primary food of blue whales, concentrated in upwelling waters west of the archipelago (Palacios, 1999).
Globally, killer whales interact with at least 18 elasmobranch species; cookiecutter sharks, requiem sharks, and mobula rays are the most frequent (Luck et al., 2026). Baleen whales filter small, schooling prey; toothed whales pursue larger, individual prey.
Cooperative hunting — Killer whale pods coordinate attacks on large prey — head-butting, biting the ventral and caudal regions, flipping and submerging it. Documented in whale shark predation events lasting up to 30 minutes.
Group fusion — Galápagos killer whale pods merge into larger groups specifically to hunt large prey such as baleen whales (Denkinger et al., 2020).
Surface feeding — Blue whales lunge or roll at the surface with an open mouth, observed almost exclusively during the cold season (Denkinger et al., 2023).
Opportunistic cues — Frigate birds circling above a killer whale group have been recorded as a possible sign of feeding activity (Orellana-Vásquez et al., 2025).
Humboldt Current — Cold, nutrient-rich water from the south, present May–November.
Cromwell Current — Rises against the Galápagos platform, delivering nutrients to the surface nearly year-round.
Panama Current — Warm water from the north, present December–June, shifts which species are present.
Why it matters — Where currents meet, upwelling boosts plankton growth, drawing prey — and cetaceans.
Mapping feeding hotspots supports targeted marine protected area design. Tracking predator-prey interactions informs fisheries management where cetaceans and fishing fleets rely on the same species. As El Niño and climate change alter upwelling, feeding-ecology data helps predict how prey — and cetacean distribution — will shift, guiding long-term conservation planning.
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