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

AUGUST 2005 FINAL REPORT
The bumphead parrotfish is one of the most desirable and most vulnerable nearshore reef fish in the
U.S. Western Pacific Islands. Bumphead parrotfish are an important species in the live reef fish trade
as well as the aquarium trade. This species has all but disappeared from Guam’s reefs and has
shown significant declines throughout its range. Reasons attributing to the decline of this species
include 1) overexploitation and destructive fishing techniques; 2) degradation and loss of coral reef
habitats; and 3) a vulnerable life history (NMFS 2004d).
Distribution—Parrotfish are mainly a tropical species occurring in the Atlantic, Indian, and Pacific
Oceans (Froese and Pauly 2004). The majority of these species are found inhabiting the coral reefs
of the Indian and western Pacific Oceans.
The bumphead parrotfish, Bolbometopon muricatum, can be found throughout the Indo-Pacific from
the Red Sea and East Africa in the east to the Line Islands and Samoa in the west, north to
Yaeyama, south to the Great Barrier Reef and New Caledonia. In Micronesia, this species can be
found from Palau to the Caroline, Mariana, and Wake Islands (Froese and Pauly 2004).
Habitat Preferences—Parrotfish are commonly found around coral reefs, and are usually most
abundant in shallow-waters to a depth of 30 m (Westneat 2001). This species occupies a variety of
coral reef habitats including seagrass beds, coral-rich areas, sand patches, rubble or pavement fields,
lagoons, reef flats, and upper reef slopes (Myers 1999). Parrotfish sleep under ledges or wedged
against coral or rock at night (Myers 1999).
The bumphead parrotfish can be found in tropical waters from 30° N to 24° S from 1 to 30 m deep
(Froese and Pauly 2004). Adults are found in small groups in clear outer lagoons and around
seaward reefs and are often located on reef crests or fronts (WPRFMC 2001; Froese and Pauly
2004). Adults may utilize a wide range of coral and shallow-water habitat types, but juveniles are
usually found in lagoons (WPRFMC 2001).
Life History—Parrotfish spawn in pairs and groups with group spawning frequently occurring on reef
slopes associated with high current speeds. Paired spawning has been observed at the reef crest or
reef slope during peak or falling tides. Parrotfish may migrate into lagoons or to the outer reef slope in
order to spawn. Some parrotfish are diandric, forming schools and spawning groups often after
migration to specific sites, while others are monandric and are strongly site specific and practice
haremic, pair spawning. The eggs and larvae of these species are pelagic and subject to dispersal by
ocean currents (WPRFMC 2001).
At this time, no reliable data are available on the spawning and migration of the bumphead parrotfish
(Myers 1999; WPRFMC 2001; Froese and Pauly 2004).
EFH Designations—(WPRFMC 2001; Figures D-10, D-14, and D-18; Table 4-5)
Eggs and Larvae―The water column from the shoreline to the outer limit of the EEZ to a
depth of 100 m.
Juvenile and Adult―All bottom habitat and the adjacent water column from 0 to 100 m.
♦ Siganidae (Rabbitfish)
Status—Four of the 6 species of the family Siganidae are managed in Micronesia as part of the
CHCRT by the WPRFMC (2001). All 6 occur in 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). The remaining 2 species of rabbitfish found in the study area have designated
EFH under the PHCRT (WPRFMC 2001). Currently, no data are available to determine if rabbitfishes
of the CHCRT are approaching an overfished situation (NMFS 2004a). Rabbitfish are a highly
esteemed food-fish and may make up a large portion of marketable reef fish is some areas of the
western Pacific (Myers 1999). The more colorful the species in this family, the more popular they are
4-31