Aspects of Behavior
243
The most developed features of territorial and social behavior possess the
damsel fish from the genera Pomacentrus and Eupomacentrus. These small
and brave fish very successfully familiarize themselves with and defend their
benthic pasture lots, repelling much stronger and well-armed competitors
like sturgeons the urchins Diadema, and even ward off Acanthaster (Glynn
and Coldan 1988). The damsel fish Pomacentrus lividus, which inhabits the
submerged areas of the flat of most Red Sea reefs, live in large territorial
colonies comprising up to 1000 specimens (Vine 1974). The members of a
colony attack intruders jointly, even large parrot fish, biting them and
sometimes even gnawing their fins.
The social behavior of reef fish includes a rather complex system of
intrasvcific and interspecies relationships, which are served by various
kinds of signalization: light, sound or chemical. The bright sophisticated
coloration is one of the main types of light signalization. Coloration serves
as an important feature of adaptation for fish with territorial or schooling
behavior. With its aid they inform other fish about their claim or right to a
given lot of territory. The bright specific hues of the species enable them
to recognize their own from strangers even in unclear coastal water, and
so escape violent confrontations. Fish that have such a bright "placard"
(K. Lorentz) coloration do not change it according to the coloration of
the landscape, like fish with a protective one do. For example, the chaetodontids and zanklids could be pointed out, which are one of the most
spectacular reef fish. Coloration serves also many other behavioral reactions
connected with various ecological adaptations. It is used: (1) by butterly
fish, by gobiids and by some damsel fish (fam. Pomacentridae) as the
"placard" mentioned above; (2) by monogamous fish like some gobies,
chaetodontids and zanklids, for mates to signal their location to each other
so as not to get lost in complex landscapes of the reef; (3) by diurnally
migrating parrot fish and sturgeons, for orientation of individuals inside the
moving school; (4) by some schooling fish like atherinids or some grunters,
for the desorientation of predators attacking the school; (5) by some
butterfly fish for desorientation of a predator attacking an individual fish,
provoking it to get at the fish from the caudal side (false eye near the tail
and real eye masked by black stripe); (6) by some butterfly-, angel- and idol
fish, as well as by scorpaenids, cerrithiids, ballistids and box fish, for warning
the predator about the good defense, poor food quality or the possibility for
the attacker of being poisoned, and so prevent useless attacks; (7) by pelagic
fish (Chromis, Caesio) , to camouflage their bodies against the bright
background of the water column or water surface, or against the vertically
striped background of thickets of ramose corals; (8) by some blennies and
small groupers, for mimicry to resemble the fish-cleaning wrasses: making
use of the peculiarities of the cleaners they are not endangered by predators,
because predatory fish never eat the cleaners. But simulating the cleaners,
they may also get close to the clients and gnaw their fins and scales.
The squirrel fish (fam. Holocentridae) and grunters (fam. Haemulidae)
use sound signalization, producing clicking or grunting sounds (Winn et al.
243
The most developed features of territorial and social behavior possess the
damsel fish from the genera Pomacentrus and Eupomacentrus. These small
and brave fish very successfully familiarize themselves with and defend their
benthic pasture lots, repelling much stronger and well-armed competitors
like sturgeons the urchins Diadema, and even ward off Acanthaster (Glynn
and Coldan 1988). The damsel fish Pomacentrus lividus, which inhabits the
submerged areas of the flat of most Red Sea reefs, live in large territorial
colonies comprising up to 1000 specimens (Vine 1974). The members of a
colony attack intruders jointly, even large parrot fish, biting them and
sometimes even gnawing their fins.
The social behavior of reef fish includes a rather complex system of
intrasvcific and interspecies relationships, which are served by various
kinds of signalization: light, sound or chemical. The bright sophisticated
coloration is one of the main types of light signalization. Coloration serves
as an important feature of adaptation for fish with territorial or schooling
behavior. With its aid they inform other fish about their claim or right to a
given lot of territory. The bright specific hues of the species enable them
to recognize their own from strangers even in unclear coastal water, and
so escape violent confrontations. Fish that have such a bright "placard"
(K. Lorentz) coloration do not change it according to the coloration of
the landscape, like fish with a protective one do. For example, the chaetodontids and zanklids could be pointed out, which are one of the most
spectacular reef fish. Coloration serves also many other behavioral reactions
connected with various ecological adaptations. It is used: (1) by butterly
fish, by gobiids and by some damsel fish (fam. Pomacentridae) as the
"placard" mentioned above; (2) by monogamous fish like some gobies,
chaetodontids and zanklids, for mates to signal their location to each other
so as not to get lost in complex landscapes of the reef; (3) by diurnally
migrating parrot fish and sturgeons, for orientation of individuals inside the
moving school; (4) by some schooling fish like atherinids or some grunters,
for the desorientation of predators attacking the school; (5) by some
butterfly fish for desorientation of a predator attacking an individual fish,
provoking it to get at the fish from the caudal side (false eye near the tail
and real eye masked by black stripe); (6) by some butterfly-, angel- and idol
fish, as well as by scorpaenids, cerrithiids, ballistids and box fish, for warning
the predator about the good defense, poor food quality or the possibility for
the attacker of being poisoned, and so prevent useless attacks; (7) by pelagic
fish (Chromis, Caesio) , to camouflage their bodies against the bright
background of the water column or water surface, or against the vertically
striped background of thickets of ramose corals; (8) by some blennies and
small groupers, for mimicry to resemble the fish-cleaning wrasses: making
use of the peculiarities of the cleaners they are not endangered by predators,
because predatory fish never eat the cleaners. But simulating the cleaners,
they may also get close to the clients and gnaw their fins and scales.
The squirrel fish (fam. Holocentridae) and grunters (fam. Haemulidae)
use sound signalization, producing clicking or grunting sounds (Winn et al.