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F. C. FÉLIX. ET AL.

Figure 2. ANOVA test for temporal variation of monthly average of (a) temperature, (b) salinity, (c) wave height and (d) wave

period between June/04 and May/05 in surf zone habitats in Pontal do Paraná, Brazil. ( Significance level < 0.01).

Mean,

S.E. and

S.D.; *

Fish composition A total of 26,865 individuals, corresponding to 84,838 Kg in weight, were caught during the one- year sampling period. They represented 63 taxa in 28 families, (Table I). Numerically, H. clupeola (42.10 %), S. brasiliensis 1 (14.52 %), florida pompano Trachinotus carolinus (Linnaeus 1766) (11.76 %), shortfinger anchovy Anchoa lyolepis (Evermann & Marsh 1900) (10.85 %) and pejerrey Odontesthes bonariensis (Valenciennes 1835) (8.47 %) were dominant and accounted for 87.7 % of the total capture. These species were also important in terms of biomass and H. clupeola (41 %), T. carolinus (7 %) and O. bonariensis (6.5 %) altogether contributed to more than 54 % of the catch (Table I).

Planktophagous fish were more abundant , whilst representing of total species, 19 %

Temporal variation

All variables were statistically significant at 0.05 p-level. Highest captures were obtained in the course of autumn and winter months, and the lowest ones in spring (Table I and Fig. 3 a). Biomass variation followed that of fish number, with similar trends in monthly variation of mean values (Fig. 3 b). Richness decreased from June to September, when the minimum value was recorded, and subsequently, an increase occurred from January to March (Fig. 3 c). Diversity fluctuated without any seasonal pattern, and while the richest month was the most diverse, the lowest diversity mean value was found in July (Fig. 3 d). Species were heterogeneously distributed, causing a reduction in the evenness index in June and July. Conversely, the lowest species catch and the highest mean value of evenness were observed in September (Fig. 3 e).

benthophagous fish were well distributed among the species with a prevalence of 34 % of all species captured. Most species were demersal (67 %) and 63 % occurred in marine-estuarine habitats (Table I).

Most fish caught were between 30-50 mm standard length (SL) and almost all were immature (98 %). This result showed a high proportion of juvenile stage in the catches (Table I), and to

Pan-American Journal of Aquatic Sciences (2007) 2 (1): 27-39

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