Big blue
In the open ocean off the coast of Baja California, northern Mexico, California sealions (Zalophus californianus) hunt among teeming shoals of sardines and mackerel. These are rich hunting grounds, especially from October to December, as nutrients well up from the deep, attracting plankton and, in turn, fish. While these sealions generally hunt in shallow waters, they sometimes venture into deeper seas such as these, swimming hundreds of miles over several days.
Group dynamics
Near the surface of the water, California sealions often gather in groups. They are extremely social animals that, according to Henley, often demonstrate playfulness, anger and affection. This group comprises mainly adult females with some younger males; the dominant bull is out of sight.
Good vibrations
Highly sensitive whiskers (vibrissae) enable California sealions to detect…