Long-Term Changes in the Fish Assemblages of the Big Blue River Basin 40 Years after the Construction of Tuttle Creek Reservoir

Abstract Long-term changes in the fish assemblage of the Big Blue River basin, Kansas, were examined by comparison of a stream survey conducted prior to the construction of Tuttle Creek Reservoir (1957 to 1958) with two surveys conducted approximately 40 years later. The most recent survey, in 2001, included 14 of the original sites sampled in the late 1950s. The most notable changes to the fish assemblages were the introduction and presumed establishment of four species (Notropis atherinoides, Pimephales vigilax, Gambusia affinis, and Notemigonus crysoleucas) and the apparent extirpation of Macrhybopsis aestivalis. Other than the loss of M. aestivalis, incidence and relative abundance of other species remained similar to that which occurred before the construction of the reservoir. Percent similarity of the fish assemblage between the 1950s and the recent samples ranged between 34.7% and 84.4%, dependent on stream type (mud, gravel, or sand substrate). In addition, species incidence patterns were signifi...