Cabrillo Marine Aquarium

Creature Feature

California sheephead
Semicossyphus pulcher

With their powerful jaws and sharp teeth, California sheepheads strike fear into the "hearts" of hard-shelled creatures from Central California to Baja. Unfortunately, these keystone predators may also arouse the appetite of anglers and commercial trap fishermen.

Males of this species are often a prized target of spear fishermen. Immediately, their black head and tail, pink midriff and signature shelf forehead betray their identity. Although both sexes display a white chin and sharp, protruding canines, the females are strikingly less conspicuous. Unlike their male counterparts, these ladies are almost entirely pink, and lack the distinctive forehead.

It may seem rather gender biased that nature has favored males in size and distinctive coloration, however each female has the potential to become a male. Like many fishes in the wrasse family (Labridae), sheephead are protogynous hermaphrodites, meaning they all enter the world as females, but many may exit as males. Between spawning seasons, females 12 to 14 inches long may undergo a dramatic sex-change, during which they will develop the coloration, forehead and genitalia of a male.

Sheephead are relatively slow to reach maturity. Females generally take four years to mature, while sex-change occurs at about eight years of age. Consequently, their populations recover slowly and are particularly sensitive to fishing. Despite regulations by the California Department of Fish and Game restricting catch size and limiting areas where these fish may be caught, sheephead are still considered a threatened species.

Thankfully, California's Marine Life Protection Act and a network of marine reserves was implemented in Southern California at the beginning of the year. These new and improved marine protected areas represent a boon for sheephead populations by giving them a place to thrive in an underwater park.

Dr. Christopher Lowe, a CSU Long Beach professor, and Professor Jennifer Casselle, of UC Santa Barbara, recently tracked the movement of various fish, including sheephead, to determine their home ranges and the "leakiness" of MPA boundaries for particular species. Their results reveal that sheephead and other fish, which actively search for food, have larger home ranges than ambush hunters. They are also more likely to "spill" out of MPA boundaries, which cross or are close to other rocky habitats. These results helped plan more effective MPAs that help protect our sheephead populations, ensuring that Southern Californians can enjoy seeing these fascinating animals for generations to come.


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Southern California Species

The Cabrillo Marine Aquarium is home to more than 200 species of animals that live in and around the waters of Southern California. Do you have a question about these and other Southern California species? Ask a Biologist.

Haliotis sp.

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

Balanus spp.

Barnacles are hermaphroditic (they have both female and male sex organs).

Cetorhinus maximus

The basking shark is the second largest species of fish in the world.

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.

Nycticorax nycticorax

Black-crowned night herons feed at night in the same areas that other heron species feed in the day.

Prionace glauca

The blue shark has one of the largest ranges of all species of sharks.

Balaenoptera musculus

The blue whale is the largest living animal.

Lythrypnus dalli

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

Bocaccio   Arrow
Sebastes paucispinis

The bocaccio can live up to 45 years.

Bottlenose Dolphin   Arrow
Tursiops truncatus

The bottlenose dolphin uses echolocation to find its prey.

Pelecanus occidentalis

The brown pelican is the smallest of all pelicans and is the only one that plunges from the air into the water to catch its food.

Aplysia californica

Each Sea hare may lay up to eighty million eggs. However, most of the eggs are eaten by predators.

Leuresthes tenuis

Unlike other fish, grunion come completely out of the water to lay their eggs in the sand.

Paralichthys californicus

The California halibut is a flatfish with both eyes on one side of its head!

Mytilus californianus

While feeding, a mussel filters 2 to 3 quarts of water per hour.

California Scorpionfish   Arrow
Scorpaena guttata

The California scorpionfish has venom in its spines.

Zalophus californianus

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

Semicossyphus pulcher

The California sheephead are all born as females.

California Skate   Arrow
Raja inornata

The California Skate has a skeleton made completely out of cartilage.

Panulirus interruptus

California Lobsters do not have front claws.

Alopias vulpinus

The common thresher shark uses its long tail in a whip-like fashion to deliver incapacitating blows to its prey.

Phronima sedentaria

The eyes of this amphipod are so large that they make up nearly a quarter of the entire body.

Aequorea victoria

Crystal jellies can expand their mouth to eat prey half their size!

Zostera marina

Eel grass is a true plant (not a seaweed) and is one of the few flowering plants that grow in the ocean.

Uca crenulata

Males have a large claw that they wave back and forth like a fiddler.

Fin Whale   Arrow
Balaenoptera physalus

The Fin whale is the second largest animal after the blue whale

Hypsypops rubicundus

Garibaldi is the California State marine fish.

Hypsypops rubicundus

Garibaldi is the California State marine fish.

Macrocystis pyrifera

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

Heterostichus rostratus

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

Stereolepis gigas

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

Pollicipes polymerus

Gooseneck barnacles can live 20 years, or more.

Gray Whale   Arrow
Eschrichtius robustus

The gray whale is a baleen whale.

Carcharodon carcharias

The great white shark is capable of explosive bursts of speed and has been known to jump 3 meters (10 feet) out of the water.

Anthopleura xanthogrammica

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

Harbor Porpoise   Arrow
Phocoena phocoena

The harbor porpoise is one of six species of porpoise

Harbor Seal   Arrow
Phoca vitulina

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

Pagurus sp.

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

Heterodontus francisci

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

Humpback Whale   Arrow
Megaptera novaeangliae

The humpback whale has distinct patterns on the tail flukes used to identify individuals.

Paralabrax clathratus

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

Orcinus orca

The killer whale, as known as the orca, is the largest dolphin.

Krill   Arrow

Thysanoessa spinifera

Krill are eaten by whales, seals, penguins, squid and fish.

Phoebastria immutabilis

The wings of a laysan albatross are adapted to lock open into a wingspan of nearly seven feet.

Triakis semifasciata

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

Hemisquilla ensigera

Mantis shrimp are not true shrimp, but get their name because of their appearance.

Marbled Godwit   Arrow
Limosa fedoa

The marbled godwit has a long, slightly upturned bill with a dark tip and pinkish base.

Loxorhynchus crispatus

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

Minke Whale   Arrow
Balaenoptera acutorostrata

The minke whale is the smallest of the rorqual whales

Gymnothorax mordax

This eel's favorite prey is the octopus.

Norrisia norrisi

These snails travel up and down kelp every day.

Pisaster ochraceous

These sea stars are able to digest their prey outside of their bodies.

Squatina californica

The Pacific angel shark superficially looks like a ray, but is a true shark.

Eptatretus stoutii

Hagfish are considered to be the most primitive species of all living fish.

Pacific Hake   Arrow
Merluccius productus

The Pacific hake can live up to 15 years.

Scomber japonicus

The Pacific mackerel is also known as the chub mackerel or blue mackerel.

Sardinops sagax

The Pacific sardine form large schools of up to 10 million fish.

Pacific Seahorse   Arrow
Hippocampus ingens

The Pacific seahorse reverses traditional birthing roles.

Strongylocentrotus purpuratus

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

Risso's dolphin   Arrow
Grampus griseus

Adult Risso's dolphins bodies are typically heavily scarred, while calves have little or no scarring


Xenistius californiensis

These fish have an up-turned mouth to better eat plankton.

Dendraster excentricus

You can't spend these dollars, they are relatives to sea stars.

Sargo   Arrow

Anisotremus davidsoni

The sargo is the largest of the Pacific grunts.

Renilla koellikeri

A sea pansy is not a flower, but is an animal that is related to sea jellies.

Isurus oxyrinchus

The shortfin mako shark is able to elevate its body temperature almost 20°F above the surrounding water.

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).

Sperm Whale   Arrow
Physeter macrocephalus

The sperm whale is the largest of the toothed whales and the largest toothed predator.

Pachygrapsus crassipes

The striped shore crab spends at least half its time on land, but submerges at times to wet its gills.

Cephaloscyllium ventriosum

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

Tidewater Goby   Arrow
Eucyclogobius newberryi

The tidewater goby is an endangered species.

Octopus bimaculoides

Octopus are very smart and have well-developed eyes.

Larus occidentalis

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

Whale Barnacle   Arrow
Cryptolepas rhachianecti

Whale barnacles live attached to the skin of whales.

White Seabass   Arrow
Atractoscion nobilis

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

Tringa semipalmata

The willet is very territorial and will aggressively defend their nesting and feeding territory.


Creature Feature Archive

      5/17/2013 Killer Whale (Featured)
      3/31/2013 Cowcod
      2/15/2013 Crystal Jelly
      11/1/2012 Risso's dolphin
      9/6/2012 Lacy Crust Bryozoan
      8/16/2012 California sheephead
      7/31/2012 Chitons
      7/17/2012 Splitnose rockfish
      2/28/2012 Green Sea Turtle
      12/26/2011 Gray Whales
      11/16/2011 California Brown Pelican
      8/23/2011 Oarfish
      2/21/2011 Pacific Mackerel
      6/28/2010 Football Fish
      3/3/2010 Grunion
      1/12/2010 E. coli, Oh My!
      7/22/2009 Cabrillo's Fossils
      3/9/2009 Garibaldi
      11/3/2008 Laysan Albatross