Marine Resources Assessment for the Marianas Operating ... - SPREP

AUGUST 2005 FINAL REPORT
dawn or dusk as pairs or groups of males with a single female. In Hawai’i, porcupinefish have a peak
spawning in late spring with some spawning also occurring from January to September (WPRFMC
2001).
♦ Ephippidae (Spadefishes and Batfishes)
Status—Three species of batfish are managed in Micronesia as part of PHCRT by the WPRFMC
(2001), two of which occur in the CNMI and Guam (Amesbury and Myers 2001; Myers and
Donaldson 2003). All species have EFH designated within the boundaries of the study area
(WPRFMC 2001; NMFS 2004c). Currently, no data are available to determine if the batfishes of the
PHCRT are approaching an overfished situation (NMFS 2004a). None of the species found in the
study area are listed on the IUCN Red List of threatened species (IUCN 2004).
Distribution—Batfishes occur in tropical temperate sea worldwide with only the genus Platax found
in the Indo-west Pacific region of Micronesia (Debelius 2002).
Habitat Preferences—Batfishes are schooling, semi-pelagic fishes which occur over muddy, silty,
and/or sandy bottoms and coral reefs (WPRFMC 2001). Juveniles occur singly or in small groups
among mangroves and in inner sheltered lagoons or reefs (Kuiter and Debelius 2001). Adults migrate
to deeper channels and lagoons, and along deep outer reef walls where they aggregate in large
schools or occur singly or in pairs to depths ranging from 20 to 30 m (Myers 1999; Debelius 2001).
Juvenile Platax species often mimic floating leaves or crinoids, whereas adult species of Platax travel
through open water tightly-knit schools (Kuiter and Debelius 2001).
Life History—Little information is known about the spawning or egg characteristics of Indo-Pacific
ephippids (Leis and Trnski 1989). However, observations on the Atlantic spadefish Chaetodipterus
faber suggest that members of this family may migrate offshore to spawn and could explain the
formation of large schools (Kuiter and Debelius 2001).
♦ Monodactylidae (Monofishes)
Status—Only one species of this family, the diamondfish (Monodactylus argenteus), is managed in
Micronesia as part of PHCRT by the WPRFMC (2001). The diamondfish has been reported as
occurring in the CNMI and Guam (Amesbury and Myers 2001; Myers and Donaldson 2003) and has
EFH designated within the boundaries of the study area (WPRFMC 2001; NMFS 2004c). Currently,
no data are available to determine if the diamondfish of the PHCRT is approaching an overfished
situation (NMFS 2004a). It is of minor commercial importance, occasionally sold fresh in markets or
caught for the aquarium-fish trade (Kottelat 2001). This species is not listed on the IUCN Red List of
threatened species (IUCN 2004).
Distribution—The diamondfish ranges from the Red Sea to Samoa, north to the Yaeyamas, south to
New Caledonia, and Palau to the east Carolines and Marianas in Micronesia (Allen et al. 2003).
Habitat Preferences—Diamondfish are active schoolers that occur in freshwater, brackish estuaries,
and harbors but may venture over silty coastal reefs to depths of 10 m (Myers 1999; Allen et al.
2003). Juveniles and adults of this species can be found over silt, mud, sand, or coral bottoms
WPRFMC 2001). This species feeds in open water during the day and night (Debelius 2001).
Life History—Diamondfish eggs are demersal and adhesive in freshwater and probably pelagic in
seawater (WPRFMC 2001).
♦ Haemulidae (Grunts)
Status—Eleven grunt species are managed in Micronesia as part of PHCRT by the WPRFMC
(2001). Six of these species occur in the CNMI and Guam (Amesbury and Myers 2001; Myers and
Donaldson 2003) and have EFH designated within the boundaries of the study area (WPRFMC 2001;
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