Physical Description

  • Fish with a long and flattened body, shaped like a kelp blade.
  • Coloring from light brown to green to purple, depending on the habitat. (In eelgrass, they can be bright green with thin silver stripes. In kelp beds, they can be brown-green like kelp). Can have wavy stripes on their sides.
  • Long dorsal (back) fin, almost the entire length of body.
  • Deeply forked tail fin.
  • Can be up to 24 inches long.
  • Juvenile fish can change colors rapidly. Adult females can change colors, but more slowly. Adult males cannot.


  • British Columbia to southern Baja California, Mexico.
  • Uncommon north of Point Conception.


  • Live in shallow water.
  • Live in rocky areas, kelp beds, eelgrass, and tide pools.
  • Found near piers with heavy kelp growth.


  • Females often lay 700 eggs at a time.
  • Females deposit eggs into algal nests.
  • Males vigorously guard nests for up to two weeks until eggs hatch.
  • Larvae are well-developed when they hatch and stay in plankton in large schools for several weeks.


  • Small fishes, crustaceans, mollusks.


  • Octopuses.

Interesting Facts

  • They can quickly change colors during courtship or territorial displays.
  • They can also quickly change colors to camouflage in their environment.
  • Larval kelpfish sometimes school with transparent mysid shrimp.

Sources:; Cabrillo Marine Aquarium;; Seafood Watch

Photo: Kevin Lee