Site Fidelity and Movement of Etheostoma fonticola with Implications to Endangered Species Management

Abstract

We quantified site fidelity, directionality and magnitude of movement, and factors associated with movement of the endangered Fountain Darter Etheostoma fonticola, a narrowly distributed (<11 km of stream habitat) and small etheostomid, within a 200-m section of a spring-fed river on the Edwards Plateau of south-central Texas. Etheostoma fonticola exhibited high site fidelity, moving on average (±1 SD) 10 ± 17 m during a 1-year period. Site fidelity was most notable in areas with low-growing aquatic vegetation (i.e., algae or Ricca fluitans). Movement was most often towards areas with low-growing aquatic vegetation (69%), more frequently in an upstream direction (81%), in winter and spring–summer seasons (>55%), and among larger fish (>30 mm TL). Maximum distance moved was 95 m within 26 d. Movement of E. fonticola was consistent with movement of narrowly distributed and slackwater etheostomids as well as widely distributed, swift-water etheostomids. As such, movement potential and maximum movement do not satisfactorily explain why some darters are more widely distributed than others. Collectively, etheostomids conform to the theory of restricted movements among resident stream fishes, but movement of large distances occurs and is probably necessary, even among species with high site fidelity.

Received June 4, 2012; accepted April 3, 2013

ACKNOWLEDGMENTS

This project was funded by a USGS Quick Response program grant through the Columbia Environmental Research Center (CERC), by the U.S. Fish and Wildlife Service (USFWS), and by Texas State University, Department of Biology (TxState). We thank E. Little (CERC), T. Brandt (USFWS), and F. Weckerley (TxState) for their support throughout the project. We also thank A. Abuzeineh, D. Araujo, H. Dammeyer, B. Labay, T. Heard, C. Lash, K. Kollaus, D. Maxwell, R. Maxwell, S. McMillan, J. Perkin, B. Phillips, and Z. Shattuck for field assistance. Sampling permits were granted by Texas State University–San Marcos (IACUC 0816_0331_17), Texas Parks and Wildlife Department (Permit SPR-0390-045), and USFWS Threatened and Endangered Species Permit (TE676811-2). Views expressed in this manuscript are those of the authors and do not necessarily reflect the views of USFWS.