Influence of instream and landscape-level factors on the distribution of Topeka shiners Notropis topeka in Kansas streams

The Topeka shiner Notropis topeka has declined in abundance throughout its his torical range in the central U.S. As a result, this minnow was listed a s federally endangered in 1999, The objective of our study was to quantitat ively assess instream physical, chemical, and biological parameters and lan dscape-level factors influencing the distribution (i.e,, extant or extirpat ed) of Topeka shiners. We sampled 26 streams in the Flint Hills region of K ansas: 12 sites where Topeka shiners are extant; and 14 sites where they ar e extirpated, Multivariate analysis of variance was used to test whether va riables were different between extant and extirpated sites. Mean catch per effort of largemouth bass in stream pools was higher at extirpated sites, a nd species diversity by trophic guild and richness in stream pools were hig her at extirpated sites. Stepwise logistic regression was used to develop a model to predict whether Topeka shiners were extant or extirpated, Number of small impoundments per watershed area, catch per effort of largemouth ba ss Micropterus salmoides in pools, and length of pool were the only signifi cant variables in the logistic model. Our model correctly classified 83% of extant sites and 85% of extirpated sites. In a landscape-level analysis of 111 streams, only number of small impoundments per watershed area was sign ificant in the logistic model, These results provide predictive toot to ass ess instream and landscape-level characteristics for habitat management and possible reintroduction of Topeka shiners in Kansas Flint Hills streams.