Who Lives in a Kelp Forest, From Brittle Stars to Sea Otters

A kelp forest is a neighborhood with every kind of resident: worms and crabs among the holdfasts, rockfish in the canopy, sea lions and whales passing through, birds overhead. And one of its most important residents, the sea otter, helps keep the whole forest standing.

Many species of fish and marine mammals live in kelp forests for protection and food. Credit: NOAA.

Invertebrates

The most common invertebrates in kelp forests are bristle worms, scud, prawns, snails and brittle stars. They feed on the holdfasts that anchor kelp to the ocean floor and on the algae that thrive in the forest. Sea stars, anemones, crabs and jellyfish live there too. Sea urchins can be destructive: they often eat through the holdfasts and remove kelp plants completely.

Fish

A wide range of fish live in kelp forests, and many matter to commercial fishermen — among them several kinds of rockfish, including black, blue, olive and kelp rockfish.

Marine mammals

• Sea lions and seals feed on the forest's fish.
• Grey whales have been seen in kelp forests, probably using them as a refuge from predatory killer whales, and eat the abundant invertebrates and crustaceans there.
• Sea otters shelter in kelp from sharks and storms — and eat the red sea urchins that could destroy a kelp forest if left to multiply freely.

Birds

Kelp forests are a natural buffet for birds. Crows, warblers, starlings and black phoebes eat the flies, maggots and small crustaceans that are plentiful there. Gulls, terns, egrets, great blue herons and cormorants eat the fish and invertebrates. The forests also give birds a refuge from storms.

Sources

Based on "What lives in a kelp forest" from NOAA's National Ocean Service, a work of the United States government in the public domain.