Cabrillo Marine Aquarium
Kelp Forests

Kelp Forests

  The richest habitat along our Californian rocky shores is the kelp forest. Giant kelp is the largest and fastest growing of all seaweeds and forms the framework for the kelp forest community. It attracts and influences many other species of animals and plants within the forest. Later, when it tears loose as drift kelp, it provides large quantities of food for animals living on the seashore and ocean bottom.

Kelp bass, giant kelpfish, garibaldi, norris' top snail, and kelp crabs are all common inhabitants of the kelp forest. Kelp anchors to the rocky bottom with a structure called the holdfast. The holdfast has many crevices and is home to many other animals such as spiny brittlestars and amphipods. The leaf-like kelp blades (also called fronds) provide a large surface area for photosynthesis. On the blades themselves, a bryozoan can grow rapidly and completely cover a kelp blade within 3-4 weeks.

Kelp forests are found along the west coasts of North and South America, the southern tip of Africa and Australia, and islands near Antarctica. Giant kelp grows best in well mixed, cool, clear ocean water. In southern California, giant kelp beds were common until the 1950s. Changes in water conditions and the near extinction of the southern sea otter, which resulted in a population explosion of the purple sea urchin, severely reduced the size and number of local kelp beds for several years. Due to restoration efforts, kelp forests have recovered along Palos Verdes in the last several years.

Southern California Species

Abalone   Abalone   Arrow
Haliotis sp.

Young abalone with a shell size of less than 3 cm take shelter within the spines of sea urchins for protection.

Bat Star   Bat Star   Arrow
Asterina miniata

When two bat stars bump into each other they begin a slow-motion “arm wrestling” match. Each sea star tries to get its arm on top of the other’s arm.

Bluebanded Goby   Bluebanded Goby   Arrow
Lythrypnus dalli

These peaceful fish are often territorial with members of their own species.

Bocaccio   Bocaccio   Arrow
Sebastes paucispinis

The bocaccio can live up to 45 years.

California Scorpionfish   California Scorpionfish   Arrow
Scorpaena guttata

The California scorpionfish has venom in its spines.

California Sea Lion   California Sea Lion    Arrow
Zalophus californianus

Sea lions use their long front flippers to steer and propel themselves through the water.

California Spiny Lobster   California Spiny Lobster   Arrow
Panulirus interruptus

California Lobsters do not have front claws.

Garibaldi   Garibaldi   Arrow
Hypsypops rubicundus

Garibaldi is the California State marine fish.

Garibaldi, juvenile   Garibaldi, juvenile   Arrow
Hypsypops rubicundus

Garibaldi is the California State marine fish.

Giant Kelp   Giant Kelp   Arrow
Macrocystis pyrifera

Under ideal conditions, giant kelp can grow about two feet a day.

Giant Kelpfish   Giant Kelpfish   Arrow
Heterostichus rostratus

The giant kelpfish can quickly change color during courtship or territorial displays.

Giant Sea Bass   Giant Sea Bass   Arrow
Stereolepis gigas

This fish is huge, growing over 7.5 feet long and weighing over 500 pounds.

Green Sea Anemone   Green Sea Anemone    Arrow
Anthopleura xanthogrammica

Some fishes develop resistance to the green anemone's sting by covering themselves with mucus.

Harbor Seal   Harbor Seal   Arrow
Phoca vitulina

The Harbor seal is the most widely distributed species of pinniped.

Hermit Crab   Hermit Crab   Arrow
Pagurus sp.

Hermit crabs protect their rear ends by hiding it in a snail shell.

Horn Shark   Horn Shark   Arrow
Heterodontus francisci

The female horn shark lays a distinctive spiral-shaped egg case.

Kelp Bass   Kelp Bass   Arrow
Paralabrax clathratus

Kelp bass reproduce by spawning (release egg and sperm into the water column) and form large aggregations in the summer months.

Leopard Shark   Leopard Shark   Arrow
Triakis semifasciata

Leopard sharks are bottom feeders and are named because of their stripes.

Masking Crab   Masking Crab   Arrow
Loxorhynchus crispatus

The masking crab decorates itself with bits of algae, sponges and bryozoans.

Moray Eel   Moray Eel   Arrow
Gymnothorax mordax

This eel's favorite prey is the octopus.

Norris' Top Snail   Norris' Top Snail   Arrow
Norrisia norrisi

These snails travel up and down kelp every day.

Purple Sea Urchin   Purple Sea Urchin   Arrow
Strongylocentrotus purpuratus

Sea urchins have tube feet, which they use for attachment, locomotion and feeding.

Sargo   Sargo   Arrow
Anisotremus davidsoni

The sargo is the largest of the Pacific grunts.

Southern Sea Otter   Southern Sea Otter   Arrow
Enhydra lutris nereis

Sea otters do not have blubber to keep warm, instead they have very dense fur (up to one million hairs per square inch).

Swell Shark   Swell Shark   Arrow
Cephaloscyllium ventriosum

When stressed, the swell shark can “swell” by inflating its stomach by swallowing water.

Western Gull   Western Gull   Arrow
Larus occidentalis

The Western gull typically lives about 15 years, but can live to at least 25 years.

White Seabass   White Seabass   Arrow
Atractoscion nobilis

The white seabass is the largest species of croaker in California.