What do orcas eat?

They eat almost exclusively fish, unlike other orca, which eat mammals. Their favorite fish is salmon, and of the species of salmon they favor Chinook. It is believed that Chinook are their favorite because they are the largest species in this region, and provide the most nutrition and fat. Orca’s teeth are conical, so they do not chew their food. They bite or tear and then swallow the pieces whole. They can also be seen “food sharing” which may be another reason for choosing the larger of the fish. The ratio of fish eaten is: 75% Chinook, 18% Chum and 6% Coho with 1% to bottom and other types of fish. An adult orca needs about 200 pounds of fish per day.

Orca find their food primarily via sonar, or echolocation. This sonar is produced from the front bulbous portion of their head, which contains oil. The sonar sound is beamed out, then returns with a sonar “picture” of what is out there. Their sonar technique is so perfected that they can distinguish between different species of salmon! Tests were done on captive dolphin blindfolded, and they could find a dime on the bottom of their tank. Orca feeding strategies include trapping fish by using underwater cliffs and shoals, or the surface of the water. People often ask, “Do whales eat under water?” They eat above and below water. They have special bladders that look like grape clusters. These bladders are powerful and remove excess salt from the whale’s body where it is excreted as waste.