Transient Killer Whales Hunt Common Dolphins in Monterey Bay

On our mid-day departure aboard Ocean Spirit, we witnessed an extraordinary and intense predation event just over the rim of the Monterey Submarine Canyon. A pod of seven Bigg's killer whales was actively hunting a group of fifteen long-beaked common dolphins, executing high-speed ramming strikes that launched both predator and prey entirely out of the water.

The killer whales were identified as members of the CA140B family group, also known as "Louise's pod," accompanied by the well-known adult male CA151, "Jimmy." Unlike fish-eating killer whales, these Bigg's orcas are marine mammal specialists. They rely on stealth and immense physical force to hunt, using their multi-ton bodies to ram and stun fast-moving dolphins at the surface.

Conditions on the bay were remarkably calm, with a light northwest wind of 9.7 knots and a water temperature of 57.2°F. This flat surface allowed our passengers aboard the Ocean Spirit to clearly observe the hunt. In addition to the orcas, we also encountered twelve humpback whales feeding in the nutrient-rich waters nearby, drawn by the same seasonal abundance that brings the dolphins into the bay.

Seeing a predation event of this scale is a stark reminder of the raw, trophic dynamics of Monterey Bay. While these encounters can be difficult to watch, they represent the natural ecological balance of a healthy, functioning marine sanctuary.