427
12 Species Case Studies
were made at between 0530 and 0600 of pairs and small groups of six to eight
groupers that moved about 2 m above the substrate and spawned together at the
seaward entrance to an outer reef channel; the outgoing current had started to pick
up and spawning was seen every 10 min (Jim Forrest and Jeanette Denby, personal
observation 2011).
After spawning, individuals disperse from the aggregation site for several days
prior to re-forming the aggregation in the subsequent spawning month. In Pohnpei,
the spawning season coincides with periods of stable water temperatures between
28
o
C and 29
o
C. In Palau, the aggregation season occurs when water temperatures
are between about 28.5°C and 29.5°C (Chap. 5 , Fig. 5.17) and in Fiji at about 24
o C
(annual range at aggregation site is approximately 24–28.5°C) (Yvonne Sadovy de
Mitcheson unpublished data).
For studies of adult female camoufl age grouper from Pohnpei, fecundity was
estimated at 1,350 oocytes g
−1 body weight for individuals examined between 22.8
and 43.0 cm SL (403–2,618 g body weight) (Rhodes and Sadovy 2002a ) . Histological
assessments of reproductively active female camoufl age grouper showed synchronous development of eggs prior to spawning, with all or nearly all ripe oocytes
spawned (Rhodes and Sadovy 2002a ) . Repeat spawning by individual females
within a reproductive month was confi rmed (Rhodes and Sadovy 2002b ) .
12.5.3 Fisheries, Management and Conservation
The camoufl age grouper is highly prized throughout much of its range and often
contributes substantially to local catches (Rhodes and Tupper 2007 ; Rhodes et al.
2008 ; Robinson et al. 2008a, b ; Yvonne Sadovy de Mitcheson, personal observation). The species is taken with a wide variety of gears, but is most targeted by spear
or hook and line, and often at spawning aggregations or along reproductive migratory pathways (e.g. Johannes et al. 1999 ; Robinson et al. 2008a, b ; Rhodes et al.
2011 ). Camoufl age grouper are sought after by local subsistence and commercial
fi shers, as well as by foreign commercial fi shing entities that include the Southeast
Asia-based live reef food fi sh trade, centred in Hong Kong, to which the species
contributes substantially (Sadovy et al. 2003a, b ) . Aggregation-fi shing has led to a
reduction of spawning aggregation abundance in many places and the likely loss of
spawning aggregations in some areas (Sadovy and Domeier 2005 ; Rhodes et al.
2011 ) . Impacts to the age and size distribution of camoufl age grouper were shown
in Pohnpei following only 1 week of intense aggregation fi shing (Rhodes et al.
2011 ) . In some areas, camoufl age grouper are found to be ciguatoxic (Myers 1999 ;
Michel Kulbicki, personal communication). The species can be hatchery-reared but
this does not occur commercially.
Currently, camoufl age grouper is listed as near threatened on the IUCN Red List
(Russell et al. 2006 ) . Management specifi cally directed at the species was introduced in Pohnpei and Palau focusing on spawning sites and during reproductive
periods. Australia has general restrictions on the amount of catch of groupers
12 Species Case Studies
were made at between 0530 and 0600 of pairs and small groups of six to eight
groupers that moved about 2 m above the substrate and spawned together at the
seaward entrance to an outer reef channel; the outgoing current had started to pick
up and spawning was seen every 10 min (Jim Forrest and Jeanette Denby, personal
observation 2011).
After spawning, individuals disperse from the aggregation site for several days
prior to re-forming the aggregation in the subsequent spawning month. In Pohnpei,
the spawning season coincides with periods of stable water temperatures between
28
o
C and 29
o
C. In Palau, the aggregation season occurs when water temperatures
are between about 28.5°C and 29.5°C (Chap. 5 , Fig. 5.17) and in Fiji at about 24
o C
(annual range at aggregation site is approximately 24–28.5°C) (Yvonne Sadovy de
Mitcheson unpublished data).
For studies of adult female camoufl age grouper from Pohnpei, fecundity was
estimated at 1,350 oocytes g
−1 body weight for individuals examined between 22.8
and 43.0 cm SL (403–2,618 g body weight) (Rhodes and Sadovy 2002a ) . Histological
assessments of reproductively active female camoufl age grouper showed synchronous development of eggs prior to spawning, with all or nearly all ripe oocytes
spawned (Rhodes and Sadovy 2002a ) . Repeat spawning by individual females
within a reproductive month was confi rmed (Rhodes and Sadovy 2002b ) .
12.5.3 Fisheries, Management and Conservation
The camoufl age grouper is highly prized throughout much of its range and often
contributes substantially to local catches (Rhodes and Tupper 2007 ; Rhodes et al.
2008 ; Robinson et al. 2008a, b ; Yvonne Sadovy de Mitcheson, personal observation). The species is taken with a wide variety of gears, but is most targeted by spear
or hook and line, and often at spawning aggregations or along reproductive migratory pathways (e.g. Johannes et al. 1999 ; Robinson et al. 2008a, b ; Rhodes et al.
2011 ). Camoufl age grouper are sought after by local subsistence and commercial
fi shers, as well as by foreign commercial fi shing entities that include the Southeast
Asia-based live reef food fi sh trade, centred in Hong Kong, to which the species
contributes substantially (Sadovy et al. 2003a, b ) . Aggregation-fi shing has led to a
reduction of spawning aggregation abundance in many places and the likely loss of
spawning aggregations in some areas (Sadovy and Domeier 2005 ; Rhodes et al.
2011 ) . Impacts to the age and size distribution of camoufl age grouper were shown
in Pohnpei following only 1 week of intense aggregation fi shing (Rhodes et al.
2011 ) . In some areas, camoufl age grouper are found to be ciguatoxic (Myers 1999 ;
Michel Kulbicki, personal communication). The species can be hatchery-reared but
this does not occur commercially.
Currently, camoufl age grouper is listed as near threatened on the IUCN Red List
(Russell et al. 2006 ) . Management specifi cally directed at the species was introduced in Pohnpei and Palau focusing on spawning sites and during reproductive
periods. Australia has general restrictions on the amount of catch of groupers