411
12 Species Case Studies
from Farquhar Atoll (Aumeeruddy and Robinson 2006 ) with brown-marbled grouper an important part of the catch. Legislation was introduced in 2005 prohibiting
the live reef food fi sh fi shery in the Seychelles, since the fi shery was not considered
in the best interests of the country (Aumeeruddy and Robinson 2006 ) . While heavy
fi shing likely reduced the population of brown-marbled grouper at Farquhar Atoll,
occasional suspension of commercial fi shing by IDC in the area for periods of up
to three years, and the remoteness from the main populated islands, may have
protected the spawning aggregation somewhat.
There are concerns throughout the Seychelles about the status of reef fi sh spawning aggregations targeted by traditional artisanal fi shers (Robinson et al. 2004 ) and
possibly in the live reef fi sh fi shery trial at Cosmoledo. The Seychelles Fishing
Authority has implemented a research programme for reef fi sh spawning aggregations, including for brown-marbled grouper, and is developing a management
framework for grouper spawning aggregations, including proposed regulations for
closed areas and seasons to protect key spawning sites and vulnerable species (SFA
2006 ) . The spatial and temporal dynamics of spawning and aggregating behaviour
were determined, with brown-marbled grouper aggregations lasting between 2 and
3 weeks in each of three consecutive months (November to February), males arriving at the aggregation before females, peak fi sh abundances a few days prior to the
new moon, and the timing of spawning probably varying interannually within a few
days leading up to and including the new moon (Robinson et al. 2008 b ) . It also
appears that large numbers of brown-marbled groupers remain on the spawning site
between aggregating months. Grouper spawning aggregations are well-known to
artisanal fi shers in the Seychelles and are in need of precautionary management
arrangements.
12.2.4 Lessons Learned, Challenges and Data Gaps
The degree of protection afforded to brown-marbled grouper spawning aggregations varies widely, and in many cases has been inadequate to prevent declines. For
example, out of 34 records for the species in the global spawning aggregation database compiled by the Society for the Conservation of Reef Fish Aggregations
(SCRFA), 11 spawning aggregations (32%) are decreasing and the status of 20
spawning aggregations (59%) are unknown ( www.SCRFA.org May 2010). Within
multi-species reef fi sheries, late-maturing, aggregation-spawning groupers will be
some of the more vulnerable species to overfi shing during both aggregation and
non-aggregation periods.
Brown-marbled grouper is vulnerable to overfi shing as it is relatively uncommon and appears to use only a few spawning aggregation sites compared to species
such as leopard coralgrouper or squaretail coralgrouper . Protection of these sites is
a high priority, and should include migratory corridors and all potential spawning
months to prevent the potential for sexual selection by the fi shery. A better understanding of (1) spatial and temporal dynamics of additional spawning aggregation
12 Species Case Studies
from Farquhar Atoll (Aumeeruddy and Robinson 2006 ) with brown-marbled grouper an important part of the catch. Legislation was introduced in 2005 prohibiting
the live reef food fi sh fi shery in the Seychelles, since the fi shery was not considered
in the best interests of the country (Aumeeruddy and Robinson 2006 ) . While heavy
fi shing likely reduced the population of brown-marbled grouper at Farquhar Atoll,
occasional suspension of commercial fi shing by IDC in the area for periods of up
to three years, and the remoteness from the main populated islands, may have
protected the spawning aggregation somewhat.
There are concerns throughout the Seychelles about the status of reef fi sh spawning aggregations targeted by traditional artisanal fi shers (Robinson et al. 2004 ) and
possibly in the live reef fi sh fi shery trial at Cosmoledo. The Seychelles Fishing
Authority has implemented a research programme for reef fi sh spawning aggregations, including for brown-marbled grouper, and is developing a management
framework for grouper spawning aggregations, including proposed regulations for
closed areas and seasons to protect key spawning sites and vulnerable species (SFA
2006 ) . The spatial and temporal dynamics of spawning and aggregating behaviour
were determined, with brown-marbled grouper aggregations lasting between 2 and
3 weeks in each of three consecutive months (November to February), males arriving at the aggregation before females, peak fi sh abundances a few days prior to the
new moon, and the timing of spawning probably varying interannually within a few
days leading up to and including the new moon (Robinson et al. 2008 b ) . It also
appears that large numbers of brown-marbled groupers remain on the spawning site
between aggregating months. Grouper spawning aggregations are well-known to
artisanal fi shers in the Seychelles and are in need of precautionary management
arrangements.
12.2.4 Lessons Learned, Challenges and Data Gaps
The degree of protection afforded to brown-marbled grouper spawning aggregations varies widely, and in many cases has been inadequate to prevent declines. For
example, out of 34 records for the species in the global spawning aggregation database compiled by the Society for the Conservation of Reef Fish Aggregations
(SCRFA), 11 spawning aggregations (32%) are decreasing and the status of 20
spawning aggregations (59%) are unknown ( www.SCRFA.org May 2010). Within
multi-species reef fi sheries, late-maturing, aggregation-spawning groupers will be
some of the more vulnerable species to overfi shing during both aggregation and
non-aggregation periods.
Brown-marbled grouper is vulnerable to overfi shing as it is relatively uncommon and appears to use only a few spawning aggregation sites compared to species
such as leopard coralgrouper or squaretail coralgrouper . Protection of these sites is
a high priority, and should include migratory corridors and all potential spawning
months to prevent the potential for sexual selection by the fi shery. A better understanding of (1) spatial and temporal dynamics of additional spawning aggregation