218
P.L. Colin
and are often easily accessed from fi eld stations. They allow collection of spawning
fi shes, their gonads and released eggs plus investigations of the relationship between
environment and reproduction. RAs are often still found in areas where TAs have
largely been eliminated by overfi shing. Research methods can often be developed
fi rst on RA and then applied to TA at a later time.
The interest of the aquaculture industry in rearing larger reef fi sh species, many
with aggregations, will provide valuable information on those factors important in
ELH, as long as those results are published in the open literature. The changes in
survival during culture through the yolk sac stage brought about by minor differences in temperature, light, salinity and turbulence (Watanabe et al. 1995, 1996,
1998 ; Ellis et al. 1997 ; Sugama et al. 2004 ; Yoseda et al. 2006 ) imply those same
factors are acting in the ocean and provide a backdrop for assessing environmental
conditions when aggregation and spawning occurs. They certainly point to the fi rst
week of life being the most sensitive for reef fi sh with pelagic eggs. A vigorous
assessment of the role of temperature regimes in relation to timing of spawning over
geographic ranges is needed; there are few data that cover the entire seasonal
temperature regime where aggregation spawning occurs.
There is need to expand studies of recruitment by larger, commercially important
reef fi shes. Light traps are useful for some, but not all, species. Methods such as channel nets, reef crest nets or other passively fi shing nets have proven useful. The success
of capturing settlement stage Nassau grouper using channel nets in the Bahamas
(Shenker et al 1993 ; Colin et al. 1997 ) as well as South Carolina (Keener et al. 1988 )
has not been replicated (attempted) elsewhere. Given the relatively small settlement
window known for the species, it would be relatively easy to replicate this effort in
other regions with tidal currents during the expected (and other) times of settlement.
The role of maternal nutrition and egg quality (McCormick 1998 ; Green and
McCormick 2005 ; Green 2008 ) merits careful attention among aggregating fi shes.
A benefi t derived from aggregation spawning (particularly for transient species)
may result from increases in egg quality, through nutritional factors, limited spawning
season, and intraspecifi c behaviour. This could be tested in a number of ways, from
comparing nutritional and hormonal status of ovaries of captured fi shes, capture of
eggs after spawning (Chap. 9 ), to experimental work. Since egg quality in some reef
fi shes with demersal eggs can increase ELH survival and growth of larvae, as well
as reduce the time in the pelagic phase, this may be of major importance in the
evolution and maintenance of aggregation spawning.
References
Akatsu S, Al-Abdul-Elah KM, Teng SK (1983) Effects of salinity and water temperature on the
survival and growth of brown spotted grouper larvae ( Epinephelus tauvina , Seranidae). J World
Maric Soc 14:624–635
Appeldoorn RS, Hensley DA, Shapiro DY, Kioroglou S, Anderson BG (1994) Egg dispersal in a
Caribbean coral reef fi sh. Thalassoma bifasciatum . II Dispersal off the reef platform. Bull Mar
Sci 54:271–280
P.L. Colin
and are often easily accessed from fi eld stations. They allow collection of spawning
fi shes, their gonads and released eggs plus investigations of the relationship between
environment and reproduction. RAs are often still found in areas where TAs have
largely been eliminated by overfi shing. Research methods can often be developed
fi rst on RA and then applied to TA at a later time.
The interest of the aquaculture industry in rearing larger reef fi sh species, many
with aggregations, will provide valuable information on those factors important in
ELH, as long as those results are published in the open literature. The changes in
survival during culture through the yolk sac stage brought about by minor differences in temperature, light, salinity and turbulence (Watanabe et al. 1995, 1996,
1998 ; Ellis et al. 1997 ; Sugama et al. 2004 ; Yoseda et al. 2006 ) imply those same
factors are acting in the ocean and provide a backdrop for assessing environmental
conditions when aggregation and spawning occurs. They certainly point to the fi rst
week of life being the most sensitive for reef fi sh with pelagic eggs. A vigorous
assessment of the role of temperature regimes in relation to timing of spawning over
geographic ranges is needed; there are few data that cover the entire seasonal
temperature regime where aggregation spawning occurs.
There is need to expand studies of recruitment by larger, commercially important
reef fi shes. Light traps are useful for some, but not all, species. Methods such as channel nets, reef crest nets or other passively fi shing nets have proven useful. The success
of capturing settlement stage Nassau grouper using channel nets in the Bahamas
(Shenker et al 1993 ; Colin et al. 1997 ) as well as South Carolina (Keener et al. 1988 )
has not been replicated (attempted) elsewhere. Given the relatively small settlement
window known for the species, it would be relatively easy to replicate this effort in
other regions with tidal currents during the expected (and other) times of settlement.
The role of maternal nutrition and egg quality (McCormick 1998 ; Green and
McCormick 2005 ; Green 2008 ) merits careful attention among aggregating fi shes.
A benefi t derived from aggregation spawning (particularly for transient species)
may result from increases in egg quality, through nutritional factors, limited spawning
season, and intraspecifi c behaviour. This could be tested in a number of ways, from
comparing nutritional and hormonal status of ovaries of captured fi shes, capture of
eggs after spawning (Chap. 9 ), to experimental work. Since egg quality in some reef
fi shes with demersal eggs can increase ELH survival and growth of larvae, as well
as reduce the time in the pelagic phase, this may be of major importance in the
evolution and maintenance of aggregation spawning.
References
Akatsu S, Al-Abdul-Elah KM, Teng SK (1983) Effects of salinity and water temperature on the
survival and growth of brown spotted grouper larvae ( Epinephelus tauvina , Seranidae). J World
Maric Soc 14:624–635
Appeldoorn RS, Hensley DA, Shapiro DY, Kioroglou S, Anderson BG (1994) Egg dispersal in a
Caribbean coral reef fi sh. Thalassoma bifasciatum . II Dispersal off the reef platform. Bull Mar
Sci 54:271–280