Tides, Salinity, and Biogeography Affect Fish Assemblage Structure and Function in Macrotidal Mangroves of the Neotropics

Abstract

Identifying the drivers that explain the distribution of tropical coastal fishes remains a central goal in biogeography. However, a lack of comparisons with standardized data still prevents more robust generalizations. Here, we assess if general assembly rules apply in two intertidal mangrove fish assemblages from different biogeographical regions (Tropical Eastern Pacific and Western Atlantic). Using multivariate analyses on field data collected for about 1 year at each location, we examined if different community attributes (species richness, taxonomic, and trophic composition, density, and catch mass) varied temporally (according to tidal-diel rhythms) and spatially (salinity gradients and between biogeographical regions). Similar total fish species richness (ca. 50 species) mirrored the regional species richness of coastal fishes in these regions. Pufferfishes (Tetraodontidae) and catfishes (Ariidae) dominated (in catch mass) fish assemblages in both regions. Closely related species within these families responded in similar ways to tidal-diel changes suggesting the existence of a phylogenetic signal in temporal niche use. The strength of the influence of tidal-diel forces determining fish habitat use were likely related to differences in mangrove topography. The biogeography of the adjacent freshwater fish fauna could explain differences in taxonomic and trophic composition between regions. Our results highlight the role that tidal-diel dynamics play in influencing the structure of fish assemblages in macrotidal areas, and suggest that considering the regional biogeographical history and the local seascape configurations could help to explain differences in mangrove fish assemblage structure across regions.

Effect of water quality variation on fish assemblages in an anthropogenically impacted tropical estuary, Colombian Pacific

“…In contrast, fish species richness was the highest at intermediate salinities, which is consistent with results from the Málaga Bay, an adjacent estuary to the Buenaventura Bay, where the highest species richness was recorded at intermediate salinities (Castellanos-Galindo and Krumme 2015). These open estuaries are characterized by a wide salinity range: low-salinity habitats (under 10 PSU) that are unsuitable for marine fish in some reported estuaries (Martino and Able 2003), as well as intermediate-salinity habitats.…”

Diel shifts in the structure and function of nearshore estuarine fish communities

“…A higher total abundance and species richness of fishes was typically observed at night, particularly in shallow nearshore waters. In several studies, the magnitude of day–night change was strongly influenced by habitat (Young et al , ; Gray et al , ; Castellanos‐Galindo & Krumme, , ) and lunar, tidal or seasonal conditions (Stoner, ; Griffiths, ; Hagan & Able, ).…”

Biogeographic patterns in major marine realms: function not taxonomy unites fish assemblages in reef, seagrass and mangrove systems

“…At global scales, biogeographic barriers are a catalyst for change in the distribution of marine organisms and in the composition of assemblages (Briggs , Bellwood and Wainwright , Floeter et al ). Tectonic movements and continental drift have opened and closed seaways, creating distinct and disjunct reefal regions.…”