380
including hermaphroditism, unisexuality (parthenogenesis), bisexuality (gonochorism), or a combination of these. The evolutionary success of fishes is due to their
complex and diversified reproductive patterns. Spawning patterns can be exemplified
as: Semelparous (spawn once and die), and Iteroparous, with its many variations such
as Isocronal, or Total Spawn (generate a batch of eggs per year), Heterochronal or
Serial Spawn (spawn some batches during the reproductive season), and Indeterminate
(multiple spawning in one season). Fertilization of eggs can be internal or external
(external is most common). In oviparous external fertilization, the type of embryonic
nutrition is lecithotropic, while those species with internal fertilization exhibit ovoviviparity which may include lecithotrophy and/or matrotrophy (common to Poeciliids).
The most observed process among oviparous species, is the lack of parental care postfertilization, with liberation of pelagic eggs (e.g., Centregraulis, Anguilla, Lutjanidae,
Epinephalidae), pelagic eggs in gelatinous masses (Scorpaena), individual demersal
release (Gadus) or in masses (Onchorhynchus). For species with present parental care,
eggs release can be as demersal masses and guard of nests (Micropterus spp. and
Pomacentrids), the release of larvae (Hemiramphids), or release of juveniles (some
Poeciliids such as Poecilia vivipara).
Among Hermaphrodites, four general patterns are known: Simultaneous,
Protogynous, Protandrous, and bidirectional sex changer (Pandian 2011). Here we
will focus on the Protogynous pattern because it is the most common in the family Epinephelidae. Due to a great plasticity and flexibility in such systems, the identification of sexuality among hermaphrodites is a difficult task (Pandian 2011), with
the histological analysis of the gonads being the most powerful tool to gender determination (Sadovy and Shapiro 1987; Sadovy de Mitcheson and Liu 2008). This
analysis often involves sacrificing the fish.
Many species in the family Epinephelidae are considered threatened or endangered by the IUCN (Sadovy de Mitcheson et al. 2013) necessitating the use of nonlethal techniques to identify gender and gonadal maturation stages. Among these
methods, it is important to mention: the use of differentiated color pattern for males
and females in reproductive aggregations (Sadovy de Mitcheson and Colin 2012),
the use of a borescope (Kynard and Kieffer 2002), sexing based on plasma sex hormone and vitellogenin levels (Craig et al. 2009a, b; Norris and Lopez 2011),
examination of the external morphology of urogenital ducts (Vecsei et al. 2003;
Koenig et al. 2016) (Fig. 14.8), use of ultrasound imaging (Colombo et al. 2004),
gonad biopsy through removed tissue with a hand-operated vacuum pump (Koenig
et al. 2016) (Fig. 14.9), ELISA for a model protein – vitellogenin (Specker and
Anderson 1994), and microsurgery (gonadectomy) (McLean 1994).
The reproductive biology of Goliath Grouper in southern Atlantic Ocean studies
were first performed in the state of Santa Catarina, Southern Brazil, using local
ecological knowledge of fishermen (Gerhardinger et al. 2009), and some gonad
sample of individuals seized during official investigations of illegal fishing. Freitas
et al. (2015), through a partnership between Conservation International Brazil, Rede
Abrolhos and Meros do Brasil Project, determined the size of sexual maturation, sex
ratio, and reproductive patterns of the species under the largest and most diverse
reef complex of southern Atlantic Ocean, the Abrolhos Bank. Samples were acquired
M. Hostim-Silva et al.
including hermaphroditism, unisexuality (parthenogenesis), bisexuality (gonochorism), or a combination of these. The evolutionary success of fishes is due to their
complex and diversified reproductive patterns. Spawning patterns can be exemplified
as: Semelparous (spawn once and die), and Iteroparous, with its many variations such
as Isocronal, or Total Spawn (generate a batch of eggs per year), Heterochronal or
Serial Spawn (spawn some batches during the reproductive season), and Indeterminate
(multiple spawning in one season). Fertilization of eggs can be internal or external
(external is most common). In oviparous external fertilization, the type of embryonic
nutrition is lecithotropic, while those species with internal fertilization exhibit ovoviviparity which may include lecithotrophy and/or matrotrophy (common to Poeciliids).
The most observed process among oviparous species, is the lack of parental care postfertilization, with liberation of pelagic eggs (e.g., Centregraulis, Anguilla, Lutjanidae,
Epinephalidae), pelagic eggs in gelatinous masses (Scorpaena), individual demersal
release (Gadus) or in masses (Onchorhynchus). For species with present parental care,
eggs release can be as demersal masses and guard of nests (Micropterus spp. and
Pomacentrids), the release of larvae (Hemiramphids), or release of juveniles (some
Poeciliids such as Poecilia vivipara).
Among Hermaphrodites, four general patterns are known: Simultaneous,
Protogynous, Protandrous, and bidirectional sex changer (Pandian 2011). Here we
will focus on the Protogynous pattern because it is the most common in the family Epinephelidae. Due to a great plasticity and flexibility in such systems, the identification of sexuality among hermaphrodites is a difficult task (Pandian 2011), with
the histological analysis of the gonads being the most powerful tool to gender determination (Sadovy and Shapiro 1987; Sadovy de Mitcheson and Liu 2008). This
analysis often involves sacrificing the fish.
Many species in the family Epinephelidae are considered threatened or endangered by the IUCN (Sadovy de Mitcheson et al. 2013) necessitating the use of nonlethal techniques to identify gender and gonadal maturation stages. Among these
methods, it is important to mention: the use of differentiated color pattern for males
and females in reproductive aggregations (Sadovy de Mitcheson and Colin 2012),
the use of a borescope (Kynard and Kieffer 2002), sexing based on plasma sex hormone and vitellogenin levels (Craig et al. 2009a, b; Norris and Lopez 2011),
examination of the external morphology of urogenital ducts (Vecsei et al. 2003;
Koenig et al. 2016) (Fig. 14.8), use of ultrasound imaging (Colombo et al. 2004),
gonad biopsy through removed tissue with a hand-operated vacuum pump (Koenig
et al. 2016) (Fig. 14.9), ELISA for a model protein – vitellogenin (Specker and
Anderson 1994), and microsurgery (gonadectomy) (McLean 1994).
The reproductive biology of Goliath Grouper in southern Atlantic Ocean studies
were first performed in the state of Santa Catarina, Southern Brazil, using local
ecological knowledge of fishermen (Gerhardinger et al. 2009), and some gonad
sample of individuals seized during official investigations of illegal fishing. Freitas
et al. (2015), through a partnership between Conservation International Brazil, Rede
Abrolhos and Meros do Brasil Project, determined the size of sexual maturation, sex
ratio, and reproductive patterns of the species under the largest and most diverse
reef complex of southern Atlantic Ocean, the Abrolhos Bank. Samples were acquired
M. Hostim-Silva et al.