Daily fish and zooplankton abundances in the littoral zone of Lake Texoma,Oklahoma-Texas, in relation to abiotic variables

Many studies have shown the effects of yearly or monthly environmental cond itions on the structure of fish and zooplankton communities. Environmental conditions can also vary greatly on much shorter time scales. We tested the effects of abiotic conditions on the daily abundance of fish and zooplankt on in the littoral zone of Lake Texoma, Oklahoma-Texas. After date was remo ved statistically from the analysis, no environmental variables were partic ularly important in determining the daily abundance of zooplankton, whereas , numbers of fish in the littoral zone were related to changes in wind velo city and wave height. Regressions of daily fish abundance against wave heig ht showed that the response differed among species and among life-history i ntervals within species. Numbers of juvenile Dorosoma petenense, Notropis a therinoides, and Morone chrysops were positively correlated with wave heigh t, whereas juvenile Menidia beryllina were negatively correlated with wave height. We suggest that changes in the abundance of particular species may be associated with (1) avoidance of inshore areas to escape possible physic al damage by wave induced turbulence, (2) attraction to inshore areas to fe ed on prey organisms suspended in the water column by wave induced turbulen ce, and (3) avoidance of inshore areas to escape high predator abundance an d increased possibility of being eaten due to turbulence.