The effect of the exotic cladoceran Daphnia lumholtzi on the native zooplankton of a central Texas reservoir.

Waco reservoir was sampled for one year at five sample sites and six months at two sample sites in an attempt to detect competition between D. lumholtzi and native zooplankton. No competition could be detected. Also monitored were egg bank densities of D. lumholtzi, temperature of water, air and sediment. The seasonality and horizontal distribution of D. lumholtzi was also monitored for Waco reservoir for one year and was monitored in Belton Reservoir for four months. Although no strong correlation existed between D. lumholtzi and water temperature or Secchi depth in Waco reservoir, D. lumholtzi densities in Belton reservoir increased along a up-river transect including increasing water temperature, and reduced Secchi depth.