You may have heard that Gray Whales fast during the long migration to and from the breeding grounds and only eat on the northern feeding grounds. So what’s up with the two Gray Whales that were recently seen feeding off the coast of Seal Beach in Southern California? Contrary to common belief, Gray whales sometimes snack along their migration route and even occasionally feed within the calving lagoons in Baja California, Mexico. Just as in their northern feeding grounds, the snacks mostly consist of amphipods (shrimplike crustations), marine worms, and other critters scooped up from sand- and mud- habitats along the shallow seafloor. The tell-tale sign that the whales are feeding, is the mud plumes produced as the whales filter out their tasty snacks from the mud and water.

http://fox5sandiego.com/2018/03/26/two-whales-spotted-near-seal-beach-shore/