Northern bobwhite (Colinus virginianus) population response to anthelminthic treatment in the Rolling Plains ecoregion of Texas, 2014–2016

Abstract

Northern bobwhite quail (Colinus virginianus) are an economically significant gamebird that has experienced continued general decline in the Rolling Plains ecoregion of Texas. Habitat loss and changing environmental conditions have been cited as major contributors to this decline, with factors such as parasites being considered inconsequential. To better assess the impacts of parasite infections on bobwhite populations in the Rolling Plains, bobwhite abundance was monitored in response to anthelminthic treatment. With the prevalence of Oxyspirura petrowi and Aulonocephalus pennula infections in quail from Mitchell County, Texas confirmed by previous studies, the anthelminthic agent Fenbendazole was introduced as a means of parasite control in 2014–2015. Bobwhite abundance was determined through a series of call counts which provided an index of bobwhite populations and were conducted throughout the course of the study. In 2016, call counts revealed a significant increase of bobwhite in the area subject to Fenbendazole treatment, while untreated areas showed no changes in abundance. Fall populations of bobwhite in the treated zone approached 300% of those in untreated areas, these findings suggest that parasites may have a more significant impact on quail populations in the Rolling Plains than previously suspected. With the importance of bobwhite as a game bird in the Rolling Plains, the potential impacts of parasites must be taken into consideration as a factor contributing to bobwhite declines. Further research into the long-term effects these parasites have on quail populations in the ecoregion may aid landowners in developing affordable and effective conservation strategies.