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Island Kelpfish

Alloclinus holderi

The island kelpfish is the smallest species of several fish who are referred to as kelpfish, the largest of which is the giant kelpfish. As the name suggests, this species of fish are common to ocean kelp forests which provide both food and protection. The island kelpfish is primarily a bottom dweller with distinctive coloration that can change to blend into their environment. Given their unique shape and various colorations they are a popular subject of marine photography.

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SPECIES IN DETAIL

Island Kelpfish

Alloclinus holderi

CONSERVATION STATUS: Least concern

CLIMATE CHANGE: Uncertain

Geographic Distribution

They range in the Eastern Pacific from Santa Cruz Island to the central area of Baja Mexico and around San Miguel Island, CA to southern Baja California. They are a southern species and are limited in biogeographical range by the Channel Islands. The increase in island kelpfish densities were a result of the warm water brought by El Nino.

Habitat

They inhabit rocky areas in depths up to 49 meters (160 feet) around kelp forest and in crevices from intertidal zone to around 91 meters (300 feet).

Physical Characteristics

They have an elongated body with a pronounced dorsal fin. Island kelpfish can change body color to match their surroundings. They vary in shades of orange, red, pink, purple, pale gray, or tan with white flecks and large brown blotches. They have stripes running the length of their body and dark spots that allows them to blend in with their surroundings and provide protection from predators. They have two separate dorsal fins and a series of cirri (arm-like appendages) around the eyes and nose with a lack of scales on the head and fins.

The keys to identifying island kelpfish include seeing that the first dorsal is the same height as the second, the elevated second dorsal rays are evenly spaced, and the kelpfish has a pale round blotch from the corner of its eye to its cheek.

Size

Their length is about 10.2 centimeters (4 inches).

Diet

Their primary diet consists of amphipods and small shrimp. They are primarily an ambush predator so lie in wait for prey to come close and then strike out quickly.

Reproduction

Females deposit from 200—1400 eggs in rocky, protected locations. Males fertilize the eggs after they have been laid by releasing of sperm over the nesting site.

Alloclinus have internal fertilization, sexual reproduction.

Behavior

Island kelpfish are generally solitary and feed during the day and take shelter at night. They are bottom feeders, staying close to their food such as small shrimp. They use the kelp forest for both feeding and protection. Given their diminutive size, they need the cover of the kelp beds or rocky reefs for protection.

Adaptation

They have the ability to change body color to match their surroundings to enhance camouflage protection from predators.

Longevity

Their longevity is unknown.

Conservation

These fish are currently classified as Least Concerned. However, any negative change in the kelp forest habitat in their geographic area from environmental or ecological changes would have a severe impact on the island kelpfish population.

Special Notes

Island kelpfish are one of several fish that have a symbiotic relationship with Giant Sea Bass by serving as a cleaner for its skin.

They are named after the American conservationist Charles Fredrick Holder (1851—1915).

SPECIES IN DETAIL | Print full entry

Island Kelpfish

Alloclinus holderi

CONSERVATION STATUS: Least concern

CLIMATE CHANGE: Uncertain

They range in the Eastern Pacific from Santa Cruz Island to the central area of Baja Mexico and around San Miguel Island, CA to southern Baja California. They are a southern species and are limited in biogeographical range by the Channel Islands. The increase in island kelpfish densities were a result of the warm water brought by El Nino.

They inhabit rocky areas in depths up to 49 meters (160 feet) around kelp forest and in crevices from intertidal zone to around 91 meters (300 feet).

They have an elongated body with a pronounced dorsal fin. Island kelpfish can change body color to match their surroundings. They vary in shades of orange, red, pink, purple, pale gray, or tan with white flecks and large brown blotches. They have stripes running the length of their body and dark spots that allows them to blend in with their surroundings and provide protection from predators. They have two separate dorsal fins and a series of cirri (arm-like appendages) around the eyes and nose with a lack of scales on the head and fins.

The keys to identifying island kelpfish include seeing that the first dorsal is the same height as the second, the elevated second dorsal rays are evenly spaced, and the kelpfish has a pale round blotch from the corner of its eye to its cheek.

Their length is about 10.2 centimeters (4 inches).

Their primary diet consists of amphipods and small shrimp. They are primarily an ambush predator so lie in wait for prey to come close and then strike out quickly.

Females deposit from 200—1400 eggs in rocky, protected locations. Males fertilize the eggs after they have been laid by releasing of sperm over the nesting site.

Alloclinus have internal fertilization, sexual reproduction.

Island kelpfish are generally solitary and feed during the day and take shelter at night. They are bottom feeders, staying close to their food such as small shrimp. They use the kelp forest for both feeding and protection. Given their diminutive size, they need the cover of the kelp beds or rocky reefs for protection.

They have the ability to change body color to match their surroundings to enhance camouflage protection from predators.

Their longevity is unknown.

These fish are currently classified as Least Concerned. However, any negative change in the kelp forest habitat in their geographic area from environmental or ecological changes would have a severe impact on the island kelpfish population.

Island kelpfish are one of several fish that have a symbiotic relationship with Giant Sea Bass by serving as a cleaner for its skin.

They are named after the American conservationist Charles Fredrick Holder (1851—1915).