Range-Wide Evaluation of Abundance, Distribution, and Habitat of Imperiled Okaloosa Darters Following Downlisting

In 2011, Okaloosa Darters (Etheostoma okaloosae) were downlisted from endangered to threatened status by the U.S. Fish and Wildlife Service. This change in conservation status was informed by data collected since 1995 during annual monitoring at a suite of fixed locations and by more spatially extensive data collected during a range-wide survey in 2005. Both sets of data indicated that there were significant numbers of Okaloosa Darters and that abundance was stable or increasing at most locations. Abundance and detection were quantified using a combination of three-pass removals and single-pass counts while snorkeling. Bayesian estimates of abundance were calculated for each site. We repeated the range-wide survey in 2014 to evaluate the status of Okaloosa Darters following the downlisting. Of the 51 resampled locations, darter abundance increased at five sites while the 95% confidence intervals of abundance overlapped at 32 sites.  Abundance declined on average 51% at the remaining 14 resampled sites. There was no change in detection rates or proportion of young-of-year between 2005 and 2014. Models using instream habitat and landscape variables as covariates are being developed to identify potential drivers of decline and to provide information to resource managers at Eglin Air Force Base.