Abstracts

Presented by James R. Morel - Email: james.morel@ttu.edu

The Oaks and Prairies Ecoregion of east-central Texas harbor numerous man-made stock ponds, which regionally are the dominant landscape water feature and collectively provide abundant habitat for wintering waterfowl. Recent Texas Parks and Wildlife Department mid-winter waterfowl surveys indicate that the Oaks and Prairies Ecoregion may harbor > 1/3 of all wintering waterfowl in Texas, with nearly half observed occurring on stock ponds. To understand temporal trends of species-specific waterfowl-use of stock ponds, we conducted 1,186 visual ground surveys during two migration and wintering seasons on 94 ponds between October 1, 2014 and February 20, 2015 (n = 503), and between September 24, 2015 and March 7, 2016 (n = 683). Unmanned aerial vehicle (UAV) surveys were also conducted to explore the efficacy of identification and potential to limit flushing behavior, often caused by visual ground surveys. During the 2015/2016 season, 40 UAV flights were conducted simultaneously during corresponding visual pond surveys. A double-blind test, utilizing four professional waterfowl biologists, was conducted to examine observer concordance and species identification while also examining the occurrence of waterfowl flushing behavior relative to visual ground surveys. Waterfowl occurrence on stock ponds declined between the 2014/2015 season and 2015/2016 season, despite an increase in survey effort and duration of survey season. Visual ground surveys were more precise than UAV surveys regarding identification and enumeration (visual ground surveys assumed to be 100% correct, UAV enumeration success = 86%, identification success = 55%). However, the potential for flushing is greater during visual ground surveys (23%) relative to UAV surveys (3%).