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

AUGUST 2005 FINAL REPORT
1998; 2001). Currently, no data are available to determine if these lobster species or the Kona crab of the
CMUS are approaching an overfished condition (NMFS 2004a). The spiny lobster is a main component of
the inshore lobster catch (Hensley and Sherwood 1993) and it is overfished on Guam (Paulay personal
communication). None of the species found in the study area are listed on the IUCN Red List of
threatened species (IUCN 2004). The ridgeback slipper lobster and the Kona crab have not been
recorded in the Marianas (Paulay personal communication).
Distribution—Members of CMUS occur in the Indo-Pacific region (Holthuis 1991; WPRFMC 1998).
There are 839 species of crustaceans in the Marianas (Paulay et al. 2003a). There are 13 species of
spiny lobster that occur in the tropical and subtropical Pacific between 35°N and 35°S (Holthuis 1991;
WPRFMC 1998). There are five species of Panulirus in the Marianas and P. penicillatus is the most
common species (WPRFMC 2001; Paulay et al. 2003a).
Habitat Preferences—In general, adults of the CMUS favor sheltered areas with rocky substrates and/or
sandy bottoms. There is a lack of published data pertaining to the preferred depth distribution of decapod
larvae and juveniles in this region (WPRFMC 2001). The spiny lobster is mainly found in windward surf
zones of oceanic reefs but some are also found on sheltered reefs (Pitcher 1993; Paulay personal
communication). Adult spiny lobsters are typically found on rocky substrate in well-protected areas, such
as crevices and under rocks (Holthuis 1991; Pitcher 1993). Some spiny lobsters prefer depths less than
10 m while others are found to depths of around 110 m (Holthuis 1991; Pitcher 1993; WPRFMC 2001;
Paulay personal communication). Small juvenile spiny lobsters are found only in the same habitat as
larger individuals (Pitcher 1993). The ridgeback spiny lobster likely occurs on rocky bottoms; it is known
from depths between 10 and 135 m (Holthuis 1991). The depth distribution of the Chinese slipper lobster
is 0 to 10 m and some are taken as incidental catch in the spiny lobster fishery (Polovina 1993). The
Chinese slipper lobster prefers to live in coral or stone reefs with a sandy bottom (Holthuis 1991). The
Kona crab is found in a number of environments, from sheltered bays and lagoons to surf zones, but
prefers sandy habitat in depths of 24 to 115 m (Smith 1993; Poupin 1996; WPRFMC 1998).
Life History—Decapods exhibit a wide range of feeding behaviors, but most combine nocturnal predation
with scavenging; large invertebrates are the typical prey items (WPRFMC 2001). Both lobsters and crabs
are ovigerous―the females carry fertilized eggs on the outside of their body. The relationships between
egg production, larval settlement, and stock recruitments are poorly understood (WPRFMC 1998, 2001).
Spiny lobsters produce eggs in summer and fall. The larvae have a pelagic distribution of about one year
and can be transported up to 3,704 km by prevailing ocean currents (WPRFMC 1998). This species is
nocturnal, hiding during the daytime in crevices in rocks and coral reefs. At night, this lobster moves up
through the surge channels to forage on the reef crest and reef flat (Pitcher 1993). The Kona crab spawns
at least twice during the spawning season; there are insufficient data to define the exact spawning season
in the study area (WPRFMC 1998). This species remains buried in the substratum during the day,
emerging only at night to search for food (Bellwood 2002).
EFH Designations—(WPRFMC 1998; Figures D-7, D-8, and D-9; Table 4-4)
Larvae―EFH for this lifestage is the water column from the shoreline to the outer limit of the
EEZ down to a depth of 150 m.
Juveniles and Adults—All bottom habitat from the shoreline to a depth of 100 m is designated
as EFH.
HAPC Designations—No HAPC is designated for Guam and the Northern Mariana Islands.
4.2.4 Coral Reef Ecosystem Management Unit Species
4.2.4.1 Introduction to Coral Reef Ecosystem Management Unit Species
The Coral Reef Ecosystem Fishery Management Plan (CRE FMP) manages coral reef ecosystems
surrounding the following U.S. Pacific Island areas: the State of Hawai’i, the Territories of American
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