The Fishes
Fish are gill-breathing vertebrates (animals with backbones) that
typically have scales and fins. Of the estimated 20,000 species of fishes
living on the earth today, about 60 percent are marine (live in
saltwater), and most of these inhabit the continental shelves of warm seas
(Cohen 1970). Based upon lists by Dahlberg (1975), Scott (Unpub.) and
Gilligan (Unpub.), it is likely that there are over 300 exclusively marine
fish species in Georgia's coastal, inner-shelf, and midshelf areas.
Roughly one-third of these are considered reef fishes and many others are
indirectly associated with reefs.
The systematic checklist (page 69) contains 150 species in 52 families, 12
orders,and 2 classes. The list contains all the fish species known to
occur at Gray's Reef National Marine Sanctuary and species that are known
to occur along the Georgia coast at the depth of Gray's Reef but have not
yet been reported at the Sanctuary. Species that have been collected,
photographed or observed at Gray's Reef are annotated with symbols that
are explained in a key at the beginning of the list. Species that were
collected or photographed during the study and which have not been
previously reported from the inner- and midshelf of Georgia are also
included in the list.
The fishes that inhabit Gray's Reef encompass a wide variety of sizes,
forms, and ecological roles. Often, the designation of species as a 'reef
fish' is unclear because species vary widely in their degree of
association with reefs and hard bottoms. It is clear, however, that after
their arrival as larvae or juveniles, some fish species are totally
dependent upon the reef for food and cover, rarely venturing away from it
during their life. Examples include angelfishes, damselfishes, and
sedentary reef dwellers such as the seahorse, the soapfish, blennies, and
gobies. Though most are day-active, many are nocturnal, seeking refuge
within the structure of the reef during the day and emerging at night to
feed. These include the bigeyes, cardinalfishes, squirrelfishes, and
morays.
Some pelagic (open-water rather than bottom-dwelling) species aggregate
near reefs in search of prey. These include the jacks, mackerels,
bluefish, cobia, barracuda and schooling fishes. Many gobies, some
wrasses, basses, and porgies inhabit the sand near reefs. Finally, some
species live in or on other species. Examples include the pearlfish which
lives in a sea cucumber, the sharksuckerand the pilotfish, that 'hitch
rides' on large animals and the silver driftfish, which lives in
association with jellyfish. |
