These zooplankton provide food for fish which are in turn eaten by birds and mammals. In addition to phytoplanton supported communities, lush growths of algae flourish in California's nearshore waters. The kelp forest is a diverse and complex community that occurs along much of the California coast. Kelp forests are composed of dense stands of large brown algae, predominately giant kelp, with an understory of various red and brown algae. The fronds, anchored on the rocky sea floor by strong holdfasts, grow upwards towards the surface, bouyed by their gas-filled floats.
Kelp forests provide food and shelter for an array of organisms.
The kelp blades and holdfasts are home to invertbrates, while anemones, abalones, sea stars, urchins, and sea cucumbers live on the rocky bottom of the forest. Kelp beds are also home to fish such as the blacksmith, kelp bass, and several species of rockfish and surfperch. Sea otters live in the canopy, feeding on the abolone, sea urchins, and other invertebrates they catch on the bottom, and harbor seals forage the kelp beds for fish. The upwelling process that occurs in nearshore waters does not occur in the open ocean off the California coast. As a result, the vast open ocean is less abundant.