type of fish poisoning, called ciguatera, is produced
by certain species of microscopic marine plants. These plants
are eaten by herbivorous fishes (especially the surgeonfish Ctenochaetus
striatus, p.
113) and the toxin is taken up by the fish. When these
herbivores are eaten by carnivorous fish, the toxin is passed
on and concentrated. The fish which tend to have the highest
concentration of the ciguatera toxin are large reef predators
such as the red snapper (p.
51) and large barracudas (p.
125). Off-shore and deep-water predators such as tuna
and bottomfish have not been implicated in ciguatera poisoning.
HOW TO USE THIS BOOK
The selection of fish
species for inclusion in this book has been based on the following
criteria:
|
a)
|
|
Species were selected to represent as many different
fish families as possible, so that the tremendous diversity
of Guam’s fish fauna could be illustrated. |
|
b)
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Within families, the most common species, those
most likely to be encountered by divers and fishermen, were
chosen. |
|
c)
|
|
As complete coverage as possible of economically
important species was attempted. |
|
d)
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|
Species of special interest, because of unusual
behavioral or ecological characteristics, were included where
possible. |
Complete species coverage
was not possible. A checklist of all species of fish known
from Guam and the southern Mariana Islands has been prepared by
J. W. Shepard and R. F. Myers (1981) and is available from the
University of Guam Marine Laboratory.
Species have been organized
by families. A family is a category used by taxonomists
(scientists who name and classify plants and animals) to include
species which are related and which show overall similarities
in their anatomy. Families are subdivided into genera (singular:
genus), groups which include closely related species. A
species is the basic unit of taxonomists and consists of a single
kind of animal. Members of a species are capable of interbreeding
to produce fertile offspring, and ordinarily members of one species
cannot mate successfully with members of other species. (However,
sometimes this does occur and hybrids are produced.) Species are
named by taxonomists according to the binomial system whereby
each species has its own unique name consisting of two parts:
the genus name, which is capitalized, and the specific name, which
is not. As an example, the scientific name of the porcupinefish
is Diodon hystrix.
This species is found in many parts of the world, and the
scientific name is always the same, even though the common name
(such as "porcupinefish") may be different from area to area.
Following the scientific name is the author's name, the
name of the taxonomist who named the species. In some cases
the author’s name is in parentheses, which indicates that
the scientific name has undergone a change (in the genus part
of the name) since it was originally applied. In order to
ensure that all members of a single species have the same scientific
name, and also to ensure that two different species do not have
the same name, there is a rather elaborate set