9‐Fluorenylmethoxycarbonyl (Fmoc) amino acids were first used for solid phase peptide synthesis a little more than a decade ago. Since that time, Fmoc solid phase peptide synthesis methodology has been greatly enhanced by the introduction of a variety of solid supports, linkages, and side chain protecting groups, as well as by increased understanding of solvation conditions. These advances have led to many impressive syntheses, such as those of biologically active and isotopically labeled peptides and small proteins. The great variety of conditions under which Fmoc solid phase peptide synthesis may be carried out represents a truly “orthogonal” scheme, and thus offers many unique opportunities for bioorganic chemistry.

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Forage‐fish management in southern ponds began in the early 1940s, and in reservoirs in the 1950s. Need for management arises from situations of both too many and too few prey for existing predators. The principal forage fishes stocked have been shads and silversides in reservoirs, sunfishes in ponds. Recent advances have been made in predator‐prey assessment methodologies, with respect to both the need for and the effects of management, but these techniques have not yet been applied widely. Management of forage fishes has included direct control of forage populations with toxicants, drawdown of water levels to increase forage availability, supplemental stocking and diversification of predators, and predator harvest regulations. Forage‐fish management has progressed from forage control to forage utilization and predator management, which makes efficient use of excess forage. Forage and predator species have been introduced with little evaluation of ecological relationships. Additional research must be done if management is to be carried out with predictable results; in the interim, management must proceed on the basis of existing principles.

The incidence of predation by largemouth bass Micropterus salmoides on fish in Lake Conroe, Texas, was examined over 7 years at two disparate levels of habitat complexity. When areal coverage of submersed vegetation ranged from 39 to 44% of the reservoir's 8,100 hectares, largemouth bass 100 mm and smaller in total length consumed fish infrequently; most did not consume fish until they reached lengths of 140 mm and more, Following the elimination of all submersed vegetation by grass carp Ctenopharyngodon idella, fish were consumed by most largemouth bass 60 mm or longer. The initiation of piscivory at smaller sizes resulted in significantly faster first‐year growth for all largemouth bass year‐classes produced after vegetation removal. Although shifts in the structure of the forage fish community occurred, ample fish prey existed for largemouth bass before and after vegetation removal. The onset of piscivory remained similar for largemouth bass collected along the dam riprap, where vegetation was absent throughout the study. These observations support the hypothesis that habitat complexity, as mediated by vegetation abundance, was the principal factor regulating piscivory by largemouth bass in the littoral zone of Lake Conroe.

Over 3,600 hectares of submersed aquatic vegetation in Lake Conroe, Texas, were eliminated 1 year after 270,000 grass carp Ctenopharyngodon idella were stocked in 1981-1982. Seventeen fish species were commonly collected in cove rotenone samples and the biomasses of eight species declined (P < 0.10) after vegetation removal. The most notable declines were observed for several small, phytophilic Lepomis spp., for bluegill Lepomis macrochirus. and for crappie Pomoxis spp. Biomass of largemouth bass Micropterus salmoides did not decline (P = 0.12) but the density of age-1 and older fish did decline (P = 0.02). Biomass and density of two cyprinid species and channel catfish Ictalurus punctatus increased. Although biomass of longear sunfish Lepomis megalotis did not increase (P = 0.11), mean size declined and density increased an order of magnitude (P = 0.02). Density of threadfin shad Dorosoma petenense increased nearly fivefold after vegetation removal, coincident with a decline in mean size; however, variability was high and the difference could not be declared significant. Biomass of gizzard shad D. cepedianum fluctuated due to inconsistent year-class production that was not directly related to vegetation coverage. Seining revealed that populations of three cyprinodontid species, bantam sunfish Lepomis symmetricus. and brook silversides Labidesthes sicculus collapsed following vegetation removal, whereas catches of inland silversides Menidia beryllina and threadfin shad increased significantly. Gillnetting revealed that large year-classes were produced by yellow bass Mor one chrysops and white bass M. mississippiensis following vegetation removal. Although abundance of white crappie Pomoxis annularis declined in offshore regions sampled by gill nets, catches of black crappie P. nigromaculatus were similar before and after vegetation removal. No change in abundance or structure over this 7-year study could be detected for at least 10 populations. The original largemouth bass-crappie-hybrid striped bass (Mor one chrysops x M. saxatilis) fishery was replaced by a channel catfish-white bass-hybrid striped bass-largemouth bass-black crappie fishery after vegetation removal. The observed response of many species to vegetation removal could be predicted given published information, but mechanisms governing the dynamics of several important species were unclear.

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–  Native fish species coexist with introduced species in Puerto Rico's freshwater systems, yet competition between these species has not been evaluated. We examined the extent of diet overlap between native bigmouth sleepers Gobiomorus dormitor and introduced largemouth bass Micropterus salmoides and peacock bass Cichla ocellaris in a Puerto Rico reservoir. Bigmouth sleepers and largemouth bass exhibited an ontogenetic shift in feeding habits, whereas peacock bass were exclusively piscivorous at all sizes collected in this study. Biologically significant diet overlap was observed between large bigmouth sleepers and largemouth bass, but not between large bigmouth sleepers and peacock bass, or between large largemouth bass and adult peacock bass. No significant diet overlap in any species combination was observed in small or medium size classes. Better understanding of the ecology of these coexisting predators should lead to improved conservation of bigmouth sleepers, and improved fisheries management for all three predatory species.

Assessment of the recruitment processes of juvenile largemouth bass Micropterus salmoides has involved a variety of gears, and little consideration has been given to the biases that gear size selection may introduce. To determine the influence of collecting methods on the interpretation of cohort characteristics, we compared length distributions of juvenile largemouth bass collected with a 9‐m bag seine, a hand‐held electrofisher, and a traditional boom‐mounted electrofisher. The hand‐held electrofisher was effective for sampling all lengths of fish up to 200 mm total length and sampled smaller fish than the boom‐mounted unit. Seining was effective for sampling fish shorter than 60 mm but, relative to the hand‐held electrofisher, it consistently underrepresented the contribution of fish longer than 70 mm to the cohort. The boom‐mounted electrofisher was effective at sampling fish longer than 150 mm, but, compared with the hand‐held electrofisher, it underestimated the contribution of smaller fish to population size structure. Gear selectivity may bias assessments of the importance of abundance and size to recruitment of juvenile largemouth bass.