In cooperation with researchers at Texas A&M University and Texas State University, the TWDB is investigating the response of aquatic biota to variation in discharge in the channel of the Middle and Lower Brazos River. This region contains more than 35 oxbow lakes that possess a wide variety of geomorphological characteristics that strongly determine the regime of flooding and dessication. The community structure of 10 oxbow lakes in this region was investigated during the summer of 1994 (Winemiller et al. 2000, Trans. Amer. Fish. Soc. 129:451-468). That study revealed substantial variation in community structure associated with species-specific responses to physical and chemical characteristics derived from disturbance regimes experienced by individual oxbow lakes. The 1994 study inferred strong relationships between river discharge, oxbow age and physical characteristics, and the value of oxbow lakes for maintenance of biodiversity and recruitment of fish stocks in the Brazos River. Substantiation of these inferences will require indentification of causal linkages between river discharge dynamics and oxbow lake faunal dynamics. The project proposed herein seeks to fill this critical information gap.

 

Lake Photos: