Water Use Behaviors and Effect on Standing Water Quality by Axis Deer (Axis axis) in The Texas Hill Country
Axis deer (Axis axis) are one of the fastest growing non-native mammalian populations in the Texas Hill Country. Although these deer have become commonplace on many Texan’s private and public properties, few studies have been performed to determine if their increasing presence is affecting the quality of standing water utilized by deer herds and individuals. Through weekly camera trap and water analyses of paired natural and control water sources, water use behaviors and effects on water quality by A. axis were studied at three sites across the Texas Hill Country - private properties along Baldwin Road in Ingram, Albert and Bessie Kronkosky State Natural Area in Pipe Creek, and HOA-owned property in the community of Fair Oaks Ranch. Camera traps were analyzed weekly with date, animal sighted, timestamp, game camera number, sex, quantity, behaviors, photo tag, and any additional notes being inputted into a comprehensive Excel® spreadsheet. Surface grab samples of both the control tanks and natural water sources were collected during each site visit and were analyzed for seven general water quality markers; nitrates, total dissolved phosphorus, chlorophyll, turbidity, suspended sediment, and coliform bacteria, including Escherichia coli. During this research, the only behaviors exhibited by A. axis regarding water usage were solely those of drinking; other behaviors such as wallowing or territorial marking were not displayed by this species. Water quality analysis appeared to indicate no influence by these deer on contaminant loading into the water sources; paired comparisons indicated minimal significant differences between the control tanks and natural water sources. Contaminant loading by other species, mainly feral hogs, appeared to have a much greater impact on water quality, indicating that A. axis are not causing any significant detrimental effects on standing water bodies within the Texas Hill Country. This study may be used as a baseline analysis of Axis deer behaviors and standing water quality in the Texas Hill Country and may be used to develop more deliberate Axis deer management plans.