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

AUGUST 2005 FINAL REPORT
coral reef areas to deep slope rocky habitats from 0 to 400 m (Heemstra and Randall 1993).
Regardless of size, groupers are typically ambush predators, hiding in crevices and among coral and
rocks (WPRFMC 2001). Most species of groupers are solitary fishes with a limited home range
(Heemstra and Randall 1993).
Life History—Spawning in groupers is typically seasonal and synchronized by lunar phase (Grimes
1987) with some species of groupers migrating several kilometers to spawn (Heemstra and Randall
1993). Groupers tend to spawn in predictable, dense aggregations (some species spawn in pairs)
with individual males spawning multiple times during the breeding season (Myers 1999; Rivera et al.
2004).
♦ Lethrinidae (Emperors)
Status—Lethrinids are managed in Micronesia as part of BMUS and PHCRT by the WPRFMC (1998,
2001). Numerous species have been reported from 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; NMFS 2004c). Emperors are commonly taken by bottom handline fishing in Guam
(Amesbury and Myers 2001) and are of moderate to significant importance in commercial,
recreational, and artisanal fisheries throughout the tropical Pacific (WPRFMC 1998). Currently, no
data are available to determine if emperor fishes 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—The emperor fish is widely distributed over the Indo-Pacific in tropical and sub-tropical
waters with a few species ranging into warm-temperate waters (Debelius 2002).
Habitat Preferences—Little is known about the biology of the emperor fish (WPRFMC 2001).
Emperors are known to occur in the deeper waters of coral reefs and adjacent sandy areas from 0 to
350 m (WPRFMC 2001). Some lethrinid species are found inhabiting coastal waters, including coral
and rocky reefs, sand flats, seagrass beds, and mangrove swamps (Debelius 2002). Most species
occur either singly or in schools to feed primarily at night on or near reefs (Myers 1999).
Life History—Spawning behavior of lethrinids is poorly documented (WPRFMC 1998). Based on
available data, spawning occurs throughout the year and is preceded by localized migrations during
crepuscular periods (Carpenter 2001b). Peak spawning events occur on or near the new moon.
Spawning occurs near the surface as well as near the bottom of reef slopes (WPRFMC 2001).
♦ Chlopsidae, Congridae, Moringuidae, and Ophichthidae (False Morays, Conger and Garden Eels,
Spaghetti Eels, and Snake Eels)
Status—Forty species of eels are managed in Micronesia as part of PHCRT by the WPRFMC (2001).
More than half of the managed eel species (60%) 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; NMFS 2004c). Currently, no data are available to determine if eels 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—Eels are distributed worldwide in tropical and temperate seas (Allen and Steene 1987).
Habitat Preferences—Both juvenile and adult eels inhabit cryptic locations in the framework of coral
reefs (e.g., false moray) or softbottom habitats (e.g., spaghetti, snake, and conger/garden eels)
(Myers 1999). Habitats vary between the different families from the false moray – secretive indwellers
of coral heads, seaward reefs, and seagrass beds at depths of 0 to 56 m; conger/garden eels –
solitary or large colonies on sand patches/flats or slopes away from reefs at depths of 7 to 53 m with
strong currents; spaghetti eels – shallow sandy areas, remaining hidden beneath the surface of the
sediment at depths of 36 to 105 m; and snake eels – indwellers that stay buried in the sand or mud
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