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significantly higher (a = 0.05) in the closed treatments. The MANOVA test performed on trophic grouping was not significant, however the univariate ANOVA performed on the benthic predators was significant (p = 0.007). lankto Copepodite and naupliar copepods and rotifers were the most abundant planktonic groups collected during the study period (Table 3). Numbers of planktonic microcrustaceans were in the range previously reported by Mabey (1993). The same four copepod species collected in the benthos also occurred in the plankton. One additional cladoceran species, Leydig_ia guadrangularis, was discovered in the plankton, but only three specimens were collected. Corixidae of the genus Tricorixa, which were almost non-existent in benthic samples, were common in the plankton. Weighted ANOVA tests indicated that all adult copepods, Eucyclops s e? ratus (Copepoda), and corixids were significantly higher (m = 0.05) in the closed treatments than in control areas (Table 4). As in the benthos, the MANOVA test performed on the trophic grouping was not significant, however the univariate ANOVA performed on benthic predators was significant (p = 0.021). In the perforated treatment the densities of invertebrate groups that showed a significant treatment affect were generally intermediate between the control and closed treatments, as would be expected if they represented an intermediate level of predation. Chlorophyll a concentrations showed no effect of the treatments, suggesting that phytoplankton biomass was unchanged. We found consistently lower chironomid diversity in the closed treatments (Table 5). Copepods, however, showed no consistent change in diversity among the treatments. 7