An often overlooked value
of Guam’s marine fishes is the value they have living free
in their natural environment. Scuba diving and snorkeling
are popular forms of recreation for Guam’s residents and
for the many visitors that come to Guam to enjoy the island's
tropical beauty. This natural heritage is a blessing that
all the people of Guam can enjoy, and the protection of the island’s
natural resources, including marine fishes, should be of concern
to us all.
CONSERVATION AND MANAGEMENT
To protect Guam’s
marine fish resources, it is necessary to protect the habitats
in which fishes live. Fishes spend their entire lives from
egg to adult immersed in water, and the quality of this water
can determine whether they live or die. Poisonous chemicals,
such as chlorine, pesticides, and petroleum, can kill fishes directly.
Other pollutants, such as sewage and organic wastes, can
take up the oxygen which is dissolved in seawater, denying it
to fish which need oxygen to survive. Heated water which
is discharged onto the reef from power plants can raise the water
temperature to the point where fish can no longer tolerate it.
The ef fects of some chemical pollutants, such as pesticides,
may be felt in areas far from where the pollutants enter the ocean.
These pollutants are taken up in small amounts by fish which
store them in their bodies. If these fish do not die as
a result of these poisons, they may be eaten by carnivorous fishes.
The carnivorous fishes accumulate more and more of the poison
with each contaminated fish they eat, and at some point the toxic
level can become high enough to kill them or render them hazardous
for human consumption.
A healthy, functioning
coral reef is also a necessary habitat requirement for reef fishes.
The reef provides food, shelter, and breeding areas for
reef fishes, and most species are adapted to live in quite specific
types of reef areas. Habitat destruction through dredging
and blasting can destroy important reef fish habitats and may
eliminate certain species of fish from these areas. The
use of dynamite and chlorine for “fishing” is a particularly
reprehensible form of habitat destruction, since those who use
these methods know the value of the fish they are killing. Dynamite
and chlorine kill not only fishes, but also the coral habitats
and food resources that these fish species require. These
habitats take years to recover, and during that time they cannot
support the fish communities that once lived there. The
use of dynamite and chlorine for fishing is now a felony on Guam,
and it is hoped that these practices will quickly die out.
Conservation is essentially
the wise use of natural resources. In the case of Guam’s
fish resources, conservation involves the management of these
resources so that the benefits of food, recreation, and economic
development can all be realized by the people of Guam today and
in the future. Because fish are living resources, they are
also renewable resources, if they are wisely managed. Management
of fishery resources requires consideration of two factors: 1)
ensuring that fish species will be able to reproduce themselves
and 2) allowing fish time to grow big enough so that the total
weight of the fish caught can be maximized. The first factor
(ensuring reproduction) can be achieved by postponing the harvest
of fish until they become old enough to reproduce, accomplished
by minimum net mesh regulations (Guam has a 2-inch minimum mesh
size for most types of