Gray whales are mysticetes (i.e., filter feeders) and are the only large cetacean known primarily as bottom feeders. They feed in shallow water with muddy or sandy bottoms or in kelp beds. To feed, they dive to the ocean floor and fill their mouths with a large volume of sediment. They force the sediment through their baleen plates, which trap a wide variety of crustaceans (Crustacea) including amphipods (Amphipoda) and ghost shrimp (Neotrypaea californiensis), as well as polychaete worms (Polychaeta), herring eggs (Clupea pallasii) and various forms of larvae. Food items are scraped off baleen plates with their large tongue and ingested.
Gray whales are considered opportunistic feeders and use group feeding strategies on schools of small fish during their southern migration. During feeding episodes, three to four whales corral a school of fish, as a single whale swims up through the school with its mouth agape. The head of the feeding whale emerges out of the water and remains in this position for up to a few minutes. Each whale in the group repeats this process until the school of fish has been significantly depleted.
Animal Foods: fish; eggs; mollusks; aquatic or marine worms; aquatic crustaceans; cnidarians; other marine invertebrates; zooplankton
Foraging Behavior: filter-feeding
Primary Diet: carnivore (Piscivore , Eats eggs, Eats non-insect arthropods, Molluscivore , Vermivore, Eats other marine invertebrates)
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- Weitcamp, L., R. Wissmar, C. Simenstad, K. Fresh, J. Odell. 1992. Gray whale foraging on ghost shrimp (Callianassa californiensis) in littoral sand flats of Puget Sound, U.S.A.. Canadian Journal of Zoology, 70: 2275-2280.