Coastal marine ecosystems are increasingly threatened by urbanization, land-based sources of pollution, and climate change. Changes in the environment due to these pressures could lead to shifts in community composition and dynamics. To address this issue, we sampled the fish assemblage of a coastal lagoon to assess species richness, rates of occurrence, and relative abundance. We caught 176,136 individuals representing 87 taxa. We compared our results to the last published survey of the study area conducted during the mid-1990s. Compared to historic data, there have been large shifts in percent occurrence in some economically important taxa, such as Lagodon rhomboides (Pinfish) increasing from 4% to 53% and Anchoa spp. (anchovies) increasing from 23% to 66%. These findings possibly indicate changes in the fish assemblage, essential fish habitat, or environment over the past 2 decades. As environmental and anthropogenic stressors continue to impact this complex coastal ecosystem, continued monitoring will be critical to detecting and understanding changes in the fish community in Mosquito Lagoon.