Spatio-temporal variation of ichthyoplankton assemblages in two lagoon systems of the Mexican Caribbean

Spatial and seasonal variation of larval fish assemblages from two lagoon systems in the Sian Ka'an Biosphere Reserve was surveyed every 3-4 mo for 1 yr (1996-1997). The two systems, which are on the east coast of Mexico's Yucatán Peninsula connect with the Caribbean Sea and have different amount of intrusion of Caribbean water. Ichthyoplankton data from surface plankton tows (500 μm mesh net) were analyzed using Correspondence Analysis to identify the main larval fish assemblages in each season. Two groups were recognized: one was oceanic influenced and the other was estuarine. The dragonet Diplogrammus pauciradiatus and the clupeids Opisthonema oglinum and Jenkinsia lamprotaenia characterized the oceanic assemblage. The estuarine assemblage was characterized by Gobiidae and Membras martinica year around and, by Hyporhamphus unifasciatus, Lupinoblennius nicholsi, Anchoa hepsetus, Archosargus rhomboidalis, and Microgobius spp. in some seasons. We propose that seasonal variations in Caribbean water inflow and reproductive strategies of adult fish in the two lagoons determine the spatial variations of the ichthyoplankton assemblages.