Influence of habitat type on diel fish associations in a tropical costal lagoon

Abstract

The abundance and turnover of fish species inhabiting Celestún lagoon were evaluated according to daynight cycles, as well as habitat type. Bimonthly sampling was done at 4 sites of the lagoon, 2 at the mouth and 2 at the inner zone. The sites for each zone include bottoms with and without submerged aquatic vegetation (VAS, FSV). At each site hydrologic parameters were registered to determine their relationship with fish community structure. Fish specimens were collected using a beach seine (15 ×1.5 m, 2.5cm mesh) at day (10:00-13:00), twilight (18:00-21:00) and night (02:00-05:00). Multivariate non-parametric (NPMANOVA, NMDS, betadisper) statistics were used for the analysis. Difference in fish species were found between habitats with VAS and FSV (F=2.6108, p=0.0114). The betadisper test indicated that species rate of replacement is low between habitats and during day-night cycles. Fish assemblages between habitats are more dynamic than day-night cycles, due to seagrass meadows that host great numbers of species providing protection and food availability.