244
Coral Reef Fish
1964). The sounds of these territorial nocturnal fish are related to their
territorial behavior. They live within colonies that spend the daytime in their
permanent lots. Upon returning from their nocturnal foraging voyages to
their permanent lots on the reef bottom for daytime relaxation, the colony
of squirrel fish produces permanent noise, which asserts the claim of the
colony to a given territory. When the intruder approaches, the fish in the
colony produce staccato sounds warning it of imminent defeat.
One sign of the high maturity of coral-reef ecosystems is the widespread
development of various forms of commensalism and symbiosis. This feature
applies to the communities of reef fish as well. They display many complex
forms of social behavior and adaptation within this kind of relationship
either between the fish themselves, or between fish and other reef animals.
Thus, the fish Caparus lives in the coeloms of holothurians, small cardinal
fish live in the mantle of the gastropod Strombus gigas, the fish Lepidogaster
sp. lives among the needles of sea urchins or amid the rays of crinoids. The
same is done by schools of small gobies or damsel-fish (chromis), using the
needles of the sea-urchins Diadema or branches of corals as their refuge.
Symbiosis is well known between a small reef fish (mostly gobies) and
shrimps. Shrimps dig out the holes and clean them, while the fish sharing the
hole with its owner give him remains of their dinners (Limbaugh 1972). But
the relationship of symbiosis is demonstrated the most clearly by the clown
fish living with the actinians (Mariscal 1970). The group of clown fish is
represented by various pomacentrid species from the genera Amphiprion
(12 species), Dascyllus (2 species) and Premnas (2 species). They are small
brightly colored fish with clear-cut placard outlines: white cross-stripes on a
bright green or red background. They live as families in the tentacles of
large reef actinians. The family includes two to three adults and several
babies (Ross 1978). The fish seek refuge in the well-armed tentacles of the
actinian, feed on mucus excreted by the host, and on its dead tissues and
remains of his food. They accomplish for the host the sanitary function of
cleaning it and even feed it sometimes, bringing to the mouth of the host
small fish caught by them in the vicinity. The clown fish bravely attack any
fish approaching the host. Although they have very poisonous nematocysts,
the host actinians never damage their symbiont fish.
Another extremely widespread kind of fish symbiosis is cleaning,
performed by several specialized species of cleaner fish. They clean their fish
clients from ectoparasites, from microbial overgrowths, and remove dead
tissues. The cleaner fish feeds on this scraped material, thus c;;ontributing to
the health of their clients. Reef fish live in warm waters and are readily
attacked by numerous parasites, molds and bacteria. Parasite density is
among the important factors regulating the density of their fish hosts
(Adlard and Lester 1988). Therefore, cleaning is one of the most vital of
their needs and life functions (Feder 1966). The fish pay close attention to
this procedure and even select their migration roots depending on the
position of the "cleaner stations", where the cleaner fish live and "work".
Coral Reef Fish
1964). The sounds of these territorial nocturnal fish are related to their
territorial behavior. They live within colonies that spend the daytime in their
permanent lots. Upon returning from their nocturnal foraging voyages to
their permanent lots on the reef bottom for daytime relaxation, the colony
of squirrel fish produces permanent noise, which asserts the claim of the
colony to a given territory. When the intruder approaches, the fish in the
colony produce staccato sounds warning it of imminent defeat.
One sign of the high maturity of coral-reef ecosystems is the widespread
development of various forms of commensalism and symbiosis. This feature
applies to the communities of reef fish as well. They display many complex
forms of social behavior and adaptation within this kind of relationship
either between the fish themselves, or between fish and other reef animals.
Thus, the fish Caparus lives in the coeloms of holothurians, small cardinal
fish live in the mantle of the gastropod Strombus gigas, the fish Lepidogaster
sp. lives among the needles of sea urchins or amid the rays of crinoids. The
same is done by schools of small gobies or damsel-fish (chromis), using the
needles of the sea-urchins Diadema or branches of corals as their refuge.
Symbiosis is well known between a small reef fish (mostly gobies) and
shrimps. Shrimps dig out the holes and clean them, while the fish sharing the
hole with its owner give him remains of their dinners (Limbaugh 1972). But
the relationship of symbiosis is demonstrated the most clearly by the clown
fish living with the actinians (Mariscal 1970). The group of clown fish is
represented by various pomacentrid species from the genera Amphiprion
(12 species), Dascyllus (2 species) and Premnas (2 species). They are small
brightly colored fish with clear-cut placard outlines: white cross-stripes on a
bright green or red background. They live as families in the tentacles of
large reef actinians. The family includes two to three adults and several
babies (Ross 1978). The fish seek refuge in the well-armed tentacles of the
actinian, feed on mucus excreted by the host, and on its dead tissues and
remains of his food. They accomplish for the host the sanitary function of
cleaning it and even feed it sometimes, bringing to the mouth of the host
small fish caught by them in the vicinity. The clown fish bravely attack any
fish approaching the host. Although they have very poisonous nematocysts,
the host actinians never damage their symbiont fish.
Another extremely widespread kind of fish symbiosis is cleaning,
performed by several specialized species of cleaner fish. They clean their fish
clients from ectoparasites, from microbial overgrowths, and remove dead
tissues. The cleaner fish feeds on this scraped material, thus c;;ontributing to
the health of their clients. Reef fish live in warm waters and are readily
attacked by numerous parasites, molds and bacteria. Parasite density is
among the important factors regulating the density of their fish hosts
(Adlard and Lester 1988). Therefore, cleaning is one of the most vital of
their needs and life functions (Feder 1966). The fish pay close attention to
this procedure and even select their migration roots depending on the
position of the "cleaner stations", where the cleaner fish live and "work".