Spatial and temporal variation in fish assemblage structure along the Paluxy River, Texas.

摘要

The distribution and abundance of the stream fishes are determined by a combination of historic, regional, and local factors. However, much of our understanding of how these factors affect stream fishes is based on taxonomic organization and not functional organization. I characterized taxonomic and functional organizations of fish assemblages from four sites along the Paluxy River across all four seasons. I used canonical correspondence analysis (CCA) to examine patterns of spatial and temporal variation in taxonomic and functional organization among stream-fish assemblages. The analyses indicate the structure of stream-fish assemblages changes spatially along the river and temporally among seasons mostly due to the overabundance of red shiner in the most downstream locality. Substrate, more than any other environmental variable, structured the fish-assemblages at this small scale.