Multi-scale habitat characteristics influence Paleback Darter occupancy and detection probability

Objective The limited distribution of the Paleback Darter Etheostoma pallididorsum, which is often associated with dynamic headwater streams, makes the species vulnerable to changes in its environment in west-central Arkansas. A detailed understanding of habitat characteristics that support the species at multiple spatial scales is limited. This project assessed the relative influences of local- and broadscale habitat characteristics on Paleback Darter occupancy and detection probability. Methods Backpack electrofishing was performed, and a mix of in situ and remote habitat characteristics was linked to the Paleback Darter data. A single-season occupancy model was used to examine factors influencing Paleback Darter occupancy. Candidate models were ranked using Akaike's information criterion corrected for small sample sizes. Results A total of 158 Paleback Darters were collected at 13 sites during 35 of the 150 surveys. Paleback Darter occupancy and detection probability were estimated to be 0.26 (95% CI = 0.16–0.40) and 0.90 (95% CI = 0.75–0.96), respectively. Distance from springs was negatively related to Paleback Darter occupancy. Conclusions Springs appear to be a key in the Paleback Darter's life history strategy, and spring preservation is likely vital to the species’ conservation.