Fish functional groups in a tropical wetland of the Yucatan Peninsula, Mexico

Abstract

The characterization of species' functional traits is a major step in the understanding and description of communities in natural habitats. The classification of species into functional groups is a useful tool to identify redundancy and uniqueness. We studied the fish community of a pristine freshwater wetland in the Sian Ka'an Biosphere Reserve by analysing two multidimensional functions: food acquisition and locomotion. We investigated changes in the functional group structure between habitats (permanent and temporary pools) and seasons (dry and wet). Six functional groups with different ecological characteristics were detected, two of which had high functional redundancy and three of them were represented by single species with unique ecological functions. In permanent pools during the dry season, functional group richness and diversity were lower, while evenness was higher. During the wet season, all functional groups were detected and similar functional group structure was found between habitats. These results suggest an effect of environmental filtering during the dry season and niche complementarity during the wet season.La caracterización de los rasgos funcionales de las especies es un paso importante en la comprensión y descripción de las comunidades en hábitats naturales. La clasificación de especies en grupos funcionales es una herramienta útil para identificar la redundancia y la especialización. Se estudió la comunidad de peces de un humedal prístino de agua dulce en la Reserva de la Biosfera de Sian Ka'an, analizando dos funciones multidimensionales: adquisición de alimento y la locomoción. Analizamos los cambios en la estructura de los grupos funcional entre hábitats (permanentes y temporales) y temporadas (lluvias y secas). Seis grupos funcionales con características ecológicas distintas fueron detectados, dos de los cuales presentaron una alta redundancia funcional y tres de ellos están representados únicamente por una especie con una función ecológica particular. En las pozas permanentes durante la temporada de secas, la riqueza y diversidad de grupos funcionales fueron menores; mientras que la equitatividad de grupos funcionales fue mayor. Durante la temporada de lluvias se detectaron todos los grupos funcionales y la estructura de los grupos fue similar entre los hábitat. Estos resultados sugieren que los filtros ambientales tienen un efecto durante la temporada de secas y la complementariedad de nicho durante la temporada de lluvias.

The role of environmental filtering in the functional structure of fish communities in tropical wetlands

“…In contrast to the dry season, previous studies suggest that the spatial variability among local communities is reduced during the wet season, and there is a high availability of food sources and favourable environmental conditions (Córdova-Tapia & Zambrano, 2016). Therefore, further research should look to determine if assembly rules change with the beginning of the wet season, when a substantial expansion of habitat occurs and all pools are completely connected.…”

“…Miyazono, Aycock, Miranda, and Tietjen (2010) tested the link between habitat connectivity and local environmental factors, and the distribution and abundance patterns of fish functional groups. These studies have shown that fish multitrophic communities in stressful systems are an excellent model to test assembly rules in natural environments (Córdova-Tapia & Zambrano, 2016;Duffy, 2002;Petchey et al, 2002;Raffaelli et al, 2002). Castellanos-Galindo and Krummel (2015) compared the assembly rules of two intertidal mangrove fish assemblages in different biogeographical regions.…”

“…In SKBR, several permanent pools are connected with the groundwater system and serve as refuges for fish during the dry season, when they must tolerate harsh conditions (Escalera-Vázquez & Zambrano, 2010). Previous studies have suggested that assembly rules may have a dynamic role in structuring fish communities, in which niche complementarity has a stronger effect during the wet season while environmental filtering acts during the dry season (Córdova-Tapia & Zambrano, 2016). Previous studies have suggested that assembly rules may have a dynamic role in structuring fish communities, in which niche complementarity has a stronger effect during the wet season while environmental filtering acts during the dry season (Córdova-Tapia & Zambrano, 2016).…”

“…A previous study in the same wetland based on functional groups showed that niche complementary may be an important driver of community structure in the wet season, when there is a high availability of food sources and favourable environmental conditions(Córdova-Tapia & Zambrano, 2016). Thus, disturbance dynamics in wetlands may be the key to understand when environmental filtering has a strong effect on community assembly.…”

Distribution, Spread, and Habitat Predictability of a Small, Invasive, Piscivorous Fish in an Important Estuarine Fish Nursery

“…The shallow-water piscivore niche of B. belizanus has other members [28], although the fact that the species is immediately piscivorous after birth [20] and is resident year-round in such systems generally differentiates it from other piscivores. The niche (described as "piscivorous in open water habitat in the middle and high water column, principally using pectoral fins for motility") is recognized as being quite distinct from other fishes in the native range [60]. The spread rate of B. belizanus estimated in the present study is intermediate to those of other invasive poeciliids.…”