The structure and composition of the fish fauna was monitored between September 2004 and April 2005, in marshlands and lagoons of the Vía Parque Isla de Salamanca. Fishes were sampled monthly, using large and small cast nets and a gill net. A total of 658 individuals were collected, belonging to 21 families and 37 species. Oreochromis niloticus y Mugil incilis were the prevailing species during the sampling period, being represented by 158 individuals weighting 34971 g and 142 individuals weighting 16457 g, respectively. Depending on habitat restriction, fish species were classified as fresh water (41%) and marine-estuarine (59%); 24% of the species are included in the lists of Colombian threatened fishes. According to their frequency of occurrence, they were classified as occasional (46%), frequent (30%), and residents (24%).
