Ecological evaluation of fish community in two lagoon-estuarine systems of the south of Chiapas, Mexico

Abstract

In the Carretas-Pereyra and Chantuto-Panzacola systems, Chiapas, Mexico, was carried out studies of fish communities. In Chantuto-Panzacola system between March and November of 1997 a total of 1456 fish represented by 31 species were collected. In Carretas-Pereyra system between February and November of 1998, were collected a total of 3081 fish represented by 19 species. Each coastal lagoon has different values of diversity and abundance related to the environmental and biological characteristics of these estuarine systems. Carretas-Pereyra present its high community values in November and April with H´ = 1.8, D = 2.06, biomass = 0.89 g/m2, density = 0.30 ind/m2 and average weight = 4.99 g/ind. Chantuto-Panzacola present its high community values in March with H´ = 2.67, D = 3.89, biomass = 1.88 g/m2 , density = 0.25 ind/m2 and average weight = 7.55 g/ind. Significant differences (ANOVA and Tukey, p<0.05) were found between the ecological parameters and the environmental variables of both ecosystems in the months of study. The multiple discriminant analysis showed that salinity and dissolved oxygen were the most important factors in variation of the community of Carretas-Pereyra, while temperature and salinity were the most important factors in ChantutoPanzacola. The frequency analysis and spatial distribution of the fish allowed defining fish assemblages formed by several groups of species that inhabit these systems. Five species were defined as dominant for Carretas-Pereyra and nine for Chantuto-Panzacola, representing 72% and 71% in number and the 81% and 76.4% in weight of the total catch respectively. These species were Achirus mazatlanus, Atherinella guatemalensis, Caranx hippos, Cathorops fuerthi, Centropomus robalito, Cichlasoma macracanthum, Cichlasoma trimaculatum, Gobiomorus maculatus, Gobionellus microdon and Lile gracilis.