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

AUGUST 2005 FINAL REPORT
Life History—Spawning for this species has not been observed (WPRFMC 2001). Daily migrations
usually occur above and away from the reef in search of food (Myers 1999).
EFH Designations—(WPRFMC 2001; Figures D-10, D-14, and D-18; Table 4-5)
Eggs and Larvae―The water column extending from the shoreline to the outer boundary of
the EEZ to a depth of 100 m.
Juvenile and Adult―All rocky/coral and sand-bottom habitat and the adjacent water column
from 0 to -9100 m.
♦ Scombridae (Mackerels)
Status—One mackerel species, the dogtooth tuna (Gymnosarda unicolor), is managed in Micronesia
as part of the CHCRT by the WPRFMC (2001) and has been reported as occurring in CNMI and
Guam (Amesbury and Myers 2001; Myers and Donaldson 2003). EFH has been designated within
the boundaries of the study area (WPRFMC 2001; NMFS 2004c) for this species. Currently, no data
are available to determine if the dogtooth tuna of the CHCRT is approaching an overfished situation
(NMFS 2004a). The dogtooth tuna is not listed on the IUCN Red List of threatened species (IUCN
2004).
Distribution—The dogtooth tuna is widely distributed throughout much of the Indo-Pacific faunal
region from the Red Sea eastward to French Polynesia (Collette and Nauen 1983).
Habitat Preferences—The dogtooth tuna is an offshore species mainly found around coral reefs.
This species may be found in deep lagoons and passes, shallow pinnacles, and off outer reef slopes
occurring in mid-water, form the surface to depths of approximately 100 m (Collette and Nauen 1983).
Dogtooth tuna prefer water temperatures ranging from 20° to 28°C (WPRFMC 2001). Dogtooth tuna
larvae are found in surface and subsurface tows, generally concentrated at depths from 20 to 30 m
(WPRFMC 2001).
Life History—Spawning activities for dogtooth tuna have been observed during the summer months
in Fiji and Papua New Guinea. Various authors have noted evidence of summer spawning events for
this species (WPRFMC 2001). Diurnal migrations have been observed in older larvae, making their
way to the surface at night (WPRFMC 2001). Spawning is believed to occur year round in tropical
locations (WPRFMC 2001). Dogtooth tuna are generally solitary species but may occur is small
schools of six or less (Froese and Pauly 2004).
EFH Designations—(WPRFMC 2001; Figures D-10, D-14, and D-18; Table 4-5)
Eggs, Larvae, Juvenile, and Adult―The water column from the shoreline to the outer
boundary of the EEZ to a depth of 100 m.
♦ Scaridae (Parrotfishes)
Status—Four species of the family Scaridae are managed in Micronesia as part of the CHCRT by the
WPRFMC (2001) and are reported as occurring in CNMI and Guam (Amesbury and Myers 2001;
Myers and Donaldson 2003). Each species has EFH designated within the boundaries of the study
area (WPRFMC 2001; NMFS 2004c). In addition, the remaining 21 species of parrotfishes found in
the study area have designated EFH under the PHCRT (WPRFMC 2001). Currently, no data are
available to determine if parrotfishes of the CHCRT are approaching an overfished situation (NMFS
2004a). Parrotfish are not a major commercial catch but they are an important food-fish and are
frequently found in fish markets (Westneat 2001; Froese and Pauly 2004). There are no species of
parrotfish listed on the IUCN Red List of threatened species but the bumphead parrotfish,
Bolbometopon muricatum, was listed as a “Species of Concern” by the NOAA Fisheries Office of
Protected Resources in 2004 (IUCN 2004; NMFS 2004d).
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