The California sheephead (Bodianus (formerly Semicossyphus) pulcher) is a species of wrasse native to the eastern Pacific Ocean.

[5] It is carnivorous, living in rocky reef and kelp bed habitats, feeding primarily on sea urchins, molluscs, and crustaceans.

All California sheephead are hatched female and morph into their male form at various stages in their lifecycle, determined by environmental conditions and pressures.

Their coral and kelp-heavy habitat provides protection from predators, which is important as this species is diurnal, foraging during the day and seeking shelter at night.

[5] Males are larger, with black tail and head sections, wide, reddish orange midriffs, red eyes, and fleshy forehead bumps.

[10] Both sexes have white chins and large, protruding canine teeth that can pry hard-shelled animals from rocks or inflict nasty puncture wounds on skin divers.

[5] The California sheephead lives in kelp forests and rocky reefs, where it feeds on sea urchins, molluscs, lobsters, and crabs.

[12] They may select rocky areas with kelp most often due to the increased habitat complexity, which likely offers additional feeding opportunities and potential refuge from large predators.

[12] Sheephead generally are considered mainly a rocky-reef and kelp-bed associated species, but they occasionally frequent sand habitats in foraging forays.

[12][14] Both the ecology and life history patterns of California sheephead have been shown to vary with local environmental conditions.

[16] As a large temperate wrasse, it is a predator of sea urchins and other benthic invertebrates and play a critical role in also regulating prey populations in kelp forests.

[17] Since it feeds heavily on urchins, it is consequently an important species for indirectly regulating kelp growth in southern California's coastal waters.

[17] Since they forage in the daytime and are considered a diurnal species, they may rely on anatomical characteristics which allow them to feed in exposed locations in broad daylight while overcoming the defenses evolved by their prey.

[12][18] As a reef fish, signals about the sheephead's predation risk often comes from the presence of damage-released chemical cues produced by injured prey animals.

[16] Patterns in the movement of California sheephead are mediated by fish sex and size; for example, large males will exhibit higher site fidelity than females.

[15] Each of the movements offshore by males is followed by a return to nearshore habitat prior to twilight, suggesting the occupation of a spawning territory at that time.

[17][20] Population densities and sex ratios of hermaphroditic fishes are also intimately linked to ecological factors and human activities.

[13] Protogynous sex change typically follows the size-advantage model, where gonadal transformation occurs once the reproductive potential of an individual would be greater as a male than as a female.

[20] The transitional phase takes between two weeks and several months, and steroid hormone concentrations are thought to be related to sex change due to the total degradation of the ovaries and the appearance of testes.