535
12 Species Case Studies
seen, but no group-spawning. For species of Prionurus , there are no known group- or
pair-spawning observations in the technical literature. The genus has several species
and is found in cooler areas, being most common in semi-tropical to temperate
waters; they occur in some tropical areas, such as Bali, where there are regular cold
water upwellings.
12.21.4 Fisheries and Ecological Importance
Surgeonfi sh are of considerable local importance in subsistence fi sheries, and some
species come under intense fi shing pressure. In Palau many fi shers have commented
on the disappearance of bluespine unicornfi sh N. unicornis , from some areas and
the generally smaller size of those taken today. When Palauans from the most populated region of Koror visit remote reef sites, such as Helen Reef where fi shing pressure is low, they are impressed with the size and abundance of “chum” found. The
larger Acanthurus , as well as Ctenochaetus are readily taken by local spearfi shers,
but it is not known whether spawning aggregations are particularly targeted for
these fi shes. Robertson ( 1983 ) reported brown surgeonfi sh from Palau, where they
are subject to spearfi shing, about half the size and weight of fi shes from remote
Aldabra Atoll, Indian Ocean. A number of colourful species, such as palette surgeonfi sh and yellow tang are popular aquarium fi shes.
Acanthurids are dominant herbivores in many areas, turning benthic primary
production into planktonic gametes which are exported. Hamner et al. ( 2007 )
found large amounts of fi sh eggs, a signifi cant portion of which were produced by
aggregation spawning striped bristletooth and brown surgeonfi sh pulsing off of a
reef in Palau on falling tides. Some of these eggs returned near the reef, while
others were transported along the reef or, in a few cases, taken further offshore, on
the next rising tide.
12.22 Dusky Rabbitfi sh, Siganus fuscescens , in Palau
Ann Hillmann Kitalong
The Environment, Inc. , P.O. Box 1696 , Koror , Palau 96940
e-mail: kitalong@palaunet.com
12.22.1 General
The dusky rabbitfi sh, Siganus fuscescens (Houttuyn 1782), is known as meas in
Palau (Fig. 12.71 ) and is widely distributed in the Indo-west Pacifi c from the
Andaman Islands to Vanuatu, Japan, Korea, Australia, New Caledonia, Palau, Yap,
12 Species Case Studies
seen, but no group-spawning. For species of Prionurus , there are no known group- or
pair-spawning observations in the technical literature. The genus has several species
and is found in cooler areas, being most common in semi-tropical to temperate
waters; they occur in some tropical areas, such as Bali, where there are regular cold
water upwellings.
12.21.4 Fisheries and Ecological Importance
Surgeonfi sh are of considerable local importance in subsistence fi sheries, and some
species come under intense fi shing pressure. In Palau many fi shers have commented
on the disappearance of bluespine unicornfi sh N. unicornis , from some areas and
the generally smaller size of those taken today. When Palauans from the most populated region of Koror visit remote reef sites, such as Helen Reef where fi shing pressure is low, they are impressed with the size and abundance of “chum” found. The
larger Acanthurus , as well as Ctenochaetus are readily taken by local spearfi shers,
but it is not known whether spawning aggregations are particularly targeted for
these fi shes. Robertson ( 1983 ) reported brown surgeonfi sh from Palau, where they
are subject to spearfi shing, about half the size and weight of fi shes from remote
Aldabra Atoll, Indian Ocean. A number of colourful species, such as palette surgeonfi sh and yellow tang are popular aquarium fi shes.
Acanthurids are dominant herbivores in many areas, turning benthic primary
production into planktonic gametes which are exported. Hamner et al. ( 2007 )
found large amounts of fi sh eggs, a signifi cant portion of which were produced by
aggregation spawning striped bristletooth and brown surgeonfi sh pulsing off of a
reef in Palau on falling tides. Some of these eggs returned near the reef, while
others were transported along the reef or, in a few cases, taken further offshore, on
the next rising tide.
12.22 Dusky Rabbitfi sh, Siganus fuscescens , in Palau
Ann Hillmann Kitalong
The Environment, Inc. , P.O. Box 1696 , Koror , Palau 96940
e-mail: kitalong@palaunet.com
12.22.1 General
The dusky rabbitfi sh, Siganus fuscescens (Houttuyn 1782), is known as meas in
Palau (Fig. 12.71 ) and is widely distributed in the Indo-west Pacifi c from the
Andaman Islands to Vanuatu, Japan, Korea, Australia, New Caledonia, Palau, Yap,