Recommendations and New Research Directions

         The most notable problem encountered during this study was the size-selective nature of the sampling methods used. This was evident for all four study species. The youngest age-classes of each species were uniformly under-represented in our samples, biasing attempts to model growth and estimate mortality rates.  The protogynous nature of P. martinicensis and H. vivanus resulted in both size-selective and sex-selective sampling biases.  Female and transitional individuals of both species were considerably under-represented in our samples.  Since female and transitional specimens are required for assessing the reproductive biology of each species, our reproductive data are not as robust as they might ideally be.

         In order to apply conventional growth models (i.e., the von Bertalanfy growth equation) and to further explore the reproductive biology of each species, it will be necessary to sample a broader size range of each target species. Future research should attempt to collect the entire range of lengths exhibited during entire life cycle of each species, specifically young-of-the-year juveniles recently settled to the substrate from the planktonic larvae stage. Many different gears were successfully employed to collect specimens during these cruises (i.e., Sabiki-type angling rigs, otter trawl, ROV suction, hand collection during mixed gas diving, and recovery from predator stomach contents). To increase the numbers of younger stages and smaller sizes, we recommend more sampling with the ROV suction sampler, and the development of small mesh trawling along with large-mesh plankton sampling. We have also found the use of mixed-gas diving to be an effective (if expensive) way to hand collect small stages in the Florida Keys (P. Thurman and R. McBride, FMRI, unpublished data).  These techniques could be applied in future work in the Gulf of Mexico.

         The seasonal coverage of our age and reproductive samples was not as complete, or as evenly distributed as would ideally be desired. Sampling cruises tended to focus on the spring and summer months (Table 1), leaving many months inadequately sampled. Better distribution of seasonal sampling would enhance all aspects of this study. Further winter sampling combined with less size-specific sampling methods would collect fish of all species, vastly improving our knowledge of the reproductive biology of all species.

         New questions have arisen during the course of the present study. Further investigation of growth rate differences among populations of P. martinicensis should address potential genetic differences among these populations – in addition to addressing differential ecological factors. Such a comprehensive approach might determine what genetic, oceanographic, or habitat-specific parameters to the growth rate variation we have documented. In addition, larger sample sizes of H. vivanus, S. phoebe, and C. enchrysurus from individual reefs would permit investigation of spatial differences, as has been possible for P. martinicensis in the present study.