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12 Species Case Studies
12.6 Nassau Grouper – Epinephelus striatus
Yvonne Sadovy de Mitcheson, Scott A. Heppell, and Patrick L. Colin
School of Biological Sciences , The University of Hong Kong ,
Hong Kong , China
e-mail: yjsadovy@hku.hk
Department of Fisheries and Wildlife , Oregon State University , Corvallis , OR , USA
e-mail: scott.heppell@oregonstate.edu
Coral Reef Research Foundation , P.O. Box 1765, Koror, Palau 96940
e-mail: crrf@palaunet.com
12.6.1 Background
The Nassau grouper, Epinephelus striatus (Family Serranidae) ranges from Bermuda
and Florida (USA), throughout The Bahamas and Caribbean Sea. The previous
report of Epinephelus striatus from the Brazilian coast south of the equator is unsubstantiated (Heemstra and Randall 1993 ; Craig et al. 2011). While not among the
largest of all groupers, the species is sizeable, reaching about 25 kg and 120 cm total
length (TL) (Sadovy and Eklund 1999 ) . The Nassau grouper was once very important commercially in the insular Caribbean. Because of severe overfi shing throughout
its range, as described below, there are few places where commercial catch of
Nassau grouper is still viable. The species is listed as endangered on the IUCN Red
List (Albins et al. 2009 ) .
12.6.2 General Biology and Early Life History
The Nassau grouper occurs in clear waters around high relief coral reefs and over
rocky substrate down to at least 130 m. Adults feed primarily on fi shes and crustaceans, with piscivory becoming more important as they grow (Randall 1965 ) . The
species reaches at least 29 years (Bush et al. 2006) with von Bertalanffy growth
parameters of L inf = 97.4 cm standard length (SL); K 0.063–0.185; log ungutted
weight (g) = −4.67 + 3.03 log SL (mm); TL (mm) = 2.24 + 1.11SL (mm) (population
parameters are reviewed in Sadovy and Eklund 1999 ) .
Genetic data indicate high gene fl ow among samples taken in Florida, Cuba,
Belize and The Bahamas (Sedberry et al. 1996 ) , thus it is presumed that Nassau
grouper maintains a single, genetically homogeneous population. A mitochondrial
DNA analysis of samples collected recently from within the Cayman Islands (Alexis
Jackson unpublished data) also failed to demonstrate anything other than a homogeneous stock structure. However, these studies are not conclusive and await the application of more sensitive genetic methods.
12 Species Case Studies
12.6 Nassau Grouper – Epinephelus striatus
Yvonne Sadovy de Mitcheson, Scott A. Heppell, and Patrick L. Colin
School of Biological Sciences , The University of Hong Kong ,
Hong Kong , China
e-mail: yjsadovy@hku.hk
Department of Fisheries and Wildlife , Oregon State University , Corvallis , OR , USA
e-mail: scott.heppell@oregonstate.edu
Coral Reef Research Foundation , P.O. Box 1765, Koror, Palau 96940
e-mail: crrf@palaunet.com
12.6.1 Background
The Nassau grouper, Epinephelus striatus (Family Serranidae) ranges from Bermuda
and Florida (USA), throughout The Bahamas and Caribbean Sea. The previous
report of Epinephelus striatus from the Brazilian coast south of the equator is unsubstantiated (Heemstra and Randall 1993 ; Craig et al. 2011). While not among the
largest of all groupers, the species is sizeable, reaching about 25 kg and 120 cm total
length (TL) (Sadovy and Eklund 1999 ) . The Nassau grouper was once very important commercially in the insular Caribbean. Because of severe overfi shing throughout
its range, as described below, there are few places where commercial catch of
Nassau grouper is still viable. The species is listed as endangered on the IUCN Red
List (Albins et al. 2009 ) .
12.6.2 General Biology and Early Life History
The Nassau grouper occurs in clear waters around high relief coral reefs and over
rocky substrate down to at least 130 m. Adults feed primarily on fi shes and crustaceans, with piscivory becoming more important as they grow (Randall 1965 ) . The
species reaches at least 29 years (Bush et al. 2006) with von Bertalanffy growth
parameters of L inf = 97.4 cm standard length (SL); K 0.063–0.185; log ungutted
weight (g) = −4.67 + 3.03 log SL (mm); TL (mm) = 2.24 + 1.11SL (mm) (population
parameters are reviewed in Sadovy and Eklund 1999 ) .
Genetic data indicate high gene fl ow among samples taken in Florida, Cuba,
Belize and The Bahamas (Sedberry et al. 1996 ) , thus it is presumed that Nassau
grouper maintains a single, genetically homogeneous population. A mitochondrial
DNA analysis of samples collected recently from within the Cayman Islands (Alexis
Jackson unpublished data) also failed to demonstrate anything other than a homogeneous stock structure. However, these studies are not conclusive and await the application of more sensitive genetic methods.