526 



Fishery Bulletin 90(3|. 1992 



below age-group 4, there is clearly no consistent rela- 

 tionship between growth rate and mortality. 



The depressions in back-calculated mean lengths 

 (Fig. 8) apply to years 1983-84 (age-group 4) and 

 1975-76 (age-group 12) for Puerto Rico, and 1984 (age- 

 group 4) and 1978 (age-group 10) for St. Thomas. In 

 the case of older age-classes, small sample sizes could 

 have produced sampling errors. However, we believe 

 that in the case of 1984, this pattern is unlikely to be 

 the result of sampling artifacts. Possible explanations 

 for lower mean back-calculated lengths in both loca- 

 tions include environmental factors, such as unusually 

 low temperatures or reduced food availability, or 

 alterations in fishing effort and associated demographic 

 changes. We know of no changes in fishing effort or 

 gear during the early 1980s at either location. Reduced 

 environmental temperatures or food availability may 

 have caused age-1 and -2 fish to experience a decrease 

 in growth rate that carried over into later years. In- 

 terestingly, catch curves developed from the same data 

 set indicate a particularly low recruitment into the 

 fishery of age-4 fish in 1984 (Sadovy and Figuerola 

 1992). This trend in the catch curves is strikingly 

 similar for both locations, strongly suggesting a region- 

 wide phenomenon. Poor recruitment into the fishery 

 of a young age-class could result from slow growth 

 early in life of individuals of that cohort. 



Examination of temperature records for the region 

 indicates that the winter of 1984 was the first since 

 that of 1975 in which the mean minimum temperature 

 dropped below 26°C (lat. 14.7°-18.2°) (Atwood and 

 Hendee In press). In summary, we suggest that lower 

 temperatures may have retarded growth in young in- 

 dividuals and that this reduction in size-at-age early in 

 life was carried through the growth history of the 

 animal. 



The red hind and fishery management 



The condition of growth overfishing in the red hind 

 (Sadovy and Figuerola 1992), and the general vulner- 

 ability of grouper species to fishing pressure, indicate 

 the urgent need for management, stock monitoring, 

 and assessment throughout its geographic range. In 

 particular, given the apparent importance of spawn- 

 ing aggregations for annual reproductive output in the 

 red hind (Bohnsack 1989; Shapiro 1987), and the in- 

 tensity with which these are exploited locally (Sadovy, 

 unpubl.), the possibility of recruitment overfishing 

 needs to be addressed. 



Acknowledgments 



We thank the Caribbean Fishery Management Coun- 

 cil, NMFS/NOAA, which is largely responsible for fun- 

 ding this research, and Omar Munoz-Roure and Miguel 

 Rolon for support in the early phases of developing this 

 study. We are particularly grateful to Richard Appel- 

 doorn, Jim Burnett-Herkes, Mark Collins, George 

 Dennis III, Doug DeVries, Allyn Johnson, Angle 

 McGehee, Charles Manooch III, and George Mitcheson 

 for information, help, and advice. Charles Manooch 

 kindly evaluated a subsample of otoliths. Stephen 

 Ralston drew our attention to implications in the data 

 we have discussed and represented as Figure 8. Thanks 

 are due to Jim Beets who provided the otolith samples 

 from St. Thomas. The cooperation and support of the 

 Exploration Team of the Fisheries Research Labora- 

 tory and of local fishermen, especially Santiago V6lez 

 Ocasio and Wilfredo Velez Ocasio, were much appre- 

 ciated. We thank Bonny Bower-Dennis who prepared 

 some of the figures. 



Age and sex 



Among sexed individuals, the majority (80%) of females 

 were ages 1-5, and the males ages 2-10. Empirical 

 mean lengths for age-groups 2-8 did not differ by sex. 

 Moe (1969) also found the empirical growth curves of 

 the sexes oiE. morio to be similar, indicating that there 

 are no marked differences in growth between the sexes 

 or sexual phases of an individual. The combination of 

 histological data, especially the presence of transi- 

 tionals, size/age frequency distributions, and a female- 

 biased sex ratio, confirm protogyny for this species in 

 Puerto Rico. However, the presence of males as young 

 as the youngest mature female indicates that at least 

 some males may develop directly from a juvenile phase 

 without passing through an initial functional female 

 phase. 



Citations 



Appeldoorn, R., J. Beets, J. Bohnsack, S. Bolden, D. Matos, 

 S. Meyers, A. Rosario, Y. Sadovy, and W. Tobias 



1992 Shallow water reef fish stock assessment for the U.S. 

 Caribbean. NOAA Tech. Memo. NMFS-SEFSC-304, NMFS 

 Southeast Fish. Sci. Cent., Miami, 70 p. 

 Atwood, D.K., and J.C. Hendee 



In press An assessment of global warming stress on Carib- 

 bean coral reef ecosystems. Proc. Gulf Caribb. Fish. Inst. 44. 

 Banneret, S.P. 



1984 The dynamics of exploited groupers (Serranidae): An in- 

 vestigation of the protogynous hermaphroditic reproductive 

 strategy. Ph.D. diss., Univ. Miami, Coral Gables, 393 p. 

 Bannerot, S.P.. W.W. Fox Jr., and J.E. Powers 



1987 Reproductive strategies and the management of snap- 

 pers and groupers in the Gulf of Mexico and Caribbean. In 

 Polovina, J.J., and S. Ralston (eds.), Tropical snappers and 

 groupers: Biology and fisheries management, p. 561-603. 

 Westview Press, Boulder. 



