Age and growth of the yellowedge grouper, Epinephelus flavolimbatus, and the yellowmouth grouper, Mycteroperca interstitialis, off Trinidad and Tobago
Manickchand-Heileman, S.C.; Phillip, D.A.T. (2000). Age and growth of the yellowedge grouper, Epinephelus flavolimbatus, and the yellowmouth grouper, Mycteroperca interstitialis, off Trinidad and Tobago. Fish. Bull. 98(2): 290-298
In: Fishery Bulletin. US Government Printing Office: Washington, D.C.. ISSN 0090-0656; e-ISSN 1937-4518, more
|   |
| Authors | | Top |
- Manickchand-Heileman, S.C.
- Phillip, D.A.T.
|
|
|
| Abstract |
Age and growth were determined for the yellowedge grouper, Epinephelus flavolimbatus, and the yellowmouth grouper, Mycteroperca interstitialis, off Trinidad and Tobago. Age was determined from cross sections of sagittae and opaque rings were counted as annuli. From the monthly variation in marginal increment ratio (marginal increment divided by the distance between the penultimate and outermost annulus), rings were found to be deposited annually from October to February in the yellowedge grouper. Monthly variation in the frequency of otoliths with an opaque margin showed that opaque rings were deposited from September to January in the yellowmouth grouper. Both species were found to grow slowly, to have long lifespans, and to achieve high asymptotic lengths. Ages between 3 and 35 years (282-985 mm TL) were found for the yellowedge grouper, for which the van Bertalanffy growth equation was Lt = 963 (1-e-0.099(t+0.08)), where Lt is length (mm) at time t (yr). Yellowmouth groupers between ages 5 and 41 years (335-827 mm FL) were found and the von Bertalanffy growth equation was Lt = 854 (1 -e-0.057(t+4.6). The length-weight relationship for the yellowedge grouper was Wt = 5x10-5TL2.80, where Wt is body weight (g) and TL is total length (mm.) For the yellowmouth grouper this relationship was Wt = 1.88x10-5FL2.94, where FL is fork length (mm.) Both species appear to grow more slowly and to achieve a greater asymptotic size and age than populations in higher latitudes, in contrast to what was expected based on differences in environmental temperature. This may be attributed to differences in fishing pressure because the populations in this study might have been subjected to a lower level of exploitation over a shorter period of time. |
|
