A study in a Mexican coastal lagoon found 44 fish species, with anchovies, sardines, and mullets being the most common. Fish abundance was highest from November to March, with more fish at Huizache than Caimanero. Diversity was similar in both areas, peaking between April and October. Certain fish species were found to be positively associated with each other. Different fish groups were linked to feeding habits and habitat types. The top predator, a catfish, was not associated with any other species.