Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil
The dusky grouper, Mycteroperca marginata, is an important commercial marine fish that is currently considered an endangered species worldwide and listed as overexploited in Brazil. Although its reproductive biology has been studied elsewhere, no information is available for populations in its south...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Sociedade Brasileira de Ictiologia
|
| Series: | Neotropical Ichthyology |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000400016&lng=en&tlng=en |
| _version_ | 1818527508119683072 |
|---|---|
| author | Elisa Seyboth Mario V Condini Cristiano Q Albuquerque Antônio S Varela Jr Gonzalo Velasco João P Vieira Alexandre M Garcia |
| author_facet | Elisa Seyboth Mario V Condini Cristiano Q Albuquerque Antônio S Varela Jr Gonzalo Velasco João P Vieira Alexandre M Garcia |
| author_sort | Elisa Seyboth |
| collection | DOAJ |
| description | The dusky grouper, Mycteroperca marginata, is an important commercial marine fish that is currently considered an endangered species worldwide and listed as overexploited in Brazil. Although its reproductive biology has been studied elsewhere, no information is available for populations in its southernmost distribution limit on the Brazilian coast. The present work investigates age structure, growth and reproduction of individuals inhabiting a pair of rocky jetties, about 4.5 km long each, located in the mouth of Patos Lagoon in the municipality of Rio Grande, in the southwestern Atlantic Ocean. A total of 130 individuals obtained between February 2007 and May 2009 were analyzed, with total length ranging from 260 to 800 mm. The growth coefficient found in the present study (K: 0.069) was lower than values reported for dusky grouper populations from the Mediterranean Sea (0.087) and southeast Africa (0.09). This difference could be related to higher average water temperatures in these regions compared to the current study site or due to poorer habitat quality in terms of the shelters available for dusky grouper individuals to establish their territories. Microscopic ovarian analyses of individuals during three years of sampling revealed only the occurrence of immature and resting females. The absence of ripe or post-spawning individuals, associated with low GSI values (<0.2) over the studied months, indicates that the dusky grouper did not use this man-made rocky substrate as a spawning site. The current L50 estimate of 451.3 mm indicates that most individuals captured in this area are immature. Such fishing pressure on immature specimens, associated with its slow growth rates and complex reproductive characteristics, threatens sustainability of the current dusky grouper fishery at the study site. |
| first_indexed | 2024-12-11T06:37:00Z |
| format | Article |
| id | doaj.art-b323d08407a744fd87e04b30e79b1560 |
| institution | Directory Open Access Journal |
| issn | 1982-0224 |
| language | English |
| last_indexed | 2024-12-11T06:37:00Z |
| publisher | Sociedade Brasileira de Ictiologia |
| record_format | Article |
| series | Neotropical Ichthyology |
| spelling | doaj.art-b323d08407a744fd87e04b30e79b15602022-12-22T01:17:21ZengSociedade Brasileira de IctiologiaNeotropical Ichthyology1982-02249484985610.1590/S1679-62252011005000038S1679-62252011000400016Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern BrazilElisa Seyboth0Mario V Condini1Cristiano Q Albuquerque2Antônio S Varela Jr3Gonzalo Velasco4João P Vieira5Alexandre M Garcia6Universidade Federal do Rio GrandeUniversidade Federal do Rio GrandeUniversidade Federal do Espírito SantoUniversidade Federal do Rio GrandeUniversidade Federal do Rio GrandeUniversidade Federal do Rio GrandeUniversidade Federal do Rio GrandeThe dusky grouper, Mycteroperca marginata, is an important commercial marine fish that is currently considered an endangered species worldwide and listed as overexploited in Brazil. Although its reproductive biology has been studied elsewhere, no information is available for populations in its southernmost distribution limit on the Brazilian coast. The present work investigates age structure, growth and reproduction of individuals inhabiting a pair of rocky jetties, about 4.5 km long each, located in the mouth of Patos Lagoon in the municipality of Rio Grande, in the southwestern Atlantic Ocean. A total of 130 individuals obtained between February 2007 and May 2009 were analyzed, with total length ranging from 260 to 800 mm. The growth coefficient found in the present study (K: 0.069) was lower than values reported for dusky grouper populations from the Mediterranean Sea (0.087) and southeast Africa (0.09). This difference could be related to higher average water temperatures in these regions compared to the current study site or due to poorer habitat quality in terms of the shelters available for dusky grouper individuals to establish their territories. Microscopic ovarian analyses of individuals during three years of sampling revealed only the occurrence of immature and resting females. The absence of ripe or post-spawning individuals, associated with low GSI values (<0.2) over the studied months, indicates that the dusky grouper did not use this man-made rocky substrate as a spawning site. The current L50 estimate of 451.3 mm indicates that most individuals captured in this area are immature. Such fishing pressure on immature specimens, associated with its slow growth rates and complex reproductive characteristics, threatens sustainability of the current dusky grouper fishery at the study site.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000400016&lng=en&tlng=enEndangered speciesEpinephelus marginatusPatos LagoonRocky jetties |
| spellingShingle | Elisa Seyboth Mario V Condini Cristiano Q Albuquerque Antônio S Varela Jr Gonzalo Velasco João P Vieira Alexandre M Garcia Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil Neotropical Ichthyology Endangered species Epinephelus marginatus Patos Lagoon Rocky jetties |
| title | Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil |
| title_full | Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil |
| title_fullStr | Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil |
| title_full_unstemmed | Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil |
| title_short | Age, growth, and reproductive aspects of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil |
| title_sort | age growth and reproductive aspects of the dusky grouper mycteroperca marginata actinopterygii epinephelidae in a man made rocky habitat in southern brazil |
| topic | Endangered species Epinephelus marginatus Patos Lagoon Rocky jetties |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000400016&lng=en&tlng=en |
| work_keys_str_mv | AT elisaseyboth agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil AT mariovcondini agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil AT cristianoqalbuquerque agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil AT antoniosvarelajr agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil AT gonzalovelasco agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil AT joaopvieira agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil AT alexandremgarcia agegrowthandreproductiveaspectsoftheduskygroupermycteropercamarginataactinopterygiiepinephelidaeinamanmaderockyhabitatinsouthernbrazil |