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Gray Whales

February – June

Every year, they travel back and forth between their feeding grounds in the arctic and their subtropical mating grounds. From November to February they pass California on the way south to Baja and again from February to June (April mostly) on their way back north – together with their calves, which is why they stay closer to the coast then.

https://www.marinemammalcenter.org/ne...

Gray whales can be seen passing by California in December and January during their southern migration, and again between mid-February and early May on their journey north. The timing of the northern migration is staggered by the age and sex of the whales, with the majority seen from the California coast in March and April.

Mothers and their newborn calves travel together and are typically the last group to migrate north, leaving the nursery lagoons only when the calves have gained enough strength. You can likely see them traveling past California throughout April and into early May. As the mothers and calves tend to hug the coast to avoid predators, they are closer and typically easier to spot from shore—leading to very special experiences for whale watchers.