Spatial distribution of nilgai antelope latrines: Implications for control of cattle fever ticks.

Authors: ZOROMSKI, LISA - Texas A&M University; DEYONG, RANDY - Texas A&M University; Goolsby, John; FOLEY, AARON - Texas A&M University; ORTEGA, ALFONSO - Texas A&M University; HEWITT, DAVID - Texas A&M University

Submitted to: The Wildlife Society
Publication Type: Abstract Only
Publication Acceptance Date: 11/30/2017
Publication Date: 2/11/2018
Citation: Zoromski, L., Deyong, R.W., Goolsby, J., Foley, A.M., Ortega, A., Hewitt, D. 2018. Spatial distribution of nilgai antelope latrines: Implications for control of cattle fever ticks.. The Wildlife Society. p. 21.

Interpretive Summary: Nilgai antelope (Boselaphus tragocamelus), are an exotic species of ungulate in Texas. Native to India, Nepal, and Pakistan, nilgai have expanded into northeast Mexico and much of coastal southern Texas since their introduction in 1924–1949. The presence of nilgai in Mexico and South Texas has complicated the eradication of cattle fever ticks (CFT; Rhipicephalus annulatus and R. microplus). CFT can transmit bovine babesiosis to cattle, which is a serious economic threat to the U.S. cattle industry. With CFT quarantine established in southern Texas, ranches with infested cattle have to comply with eradication requirements. Wildlife can hinder management efforts because white-tailed deer (Odocoileus virginianus) and nilgai are alternative hosts for CFT. Control methods, such as treated baits, are available for deer. Nilgai do not respond to bait, which is a major challenge for controlling the spread of CFT. Methods for control of CFT on nilgai are critically needed. One unique aspect of nilgai ecology is their use of communal latrines, or repeated defecation in the same location. The existence of communal gathering areas which nilgai re-visit presents an opportunity for treatment of CFT. We are characterizing the distribution and usage of latrines on ranches in South Texas. We will analyze the density, size, and location of latrines in relation to roads, habitat types, and abundance of nilgai. The results of this study will have important implications for the development of treatment methods for CFT-infested nilgai for eradication of this pest in the US.

Technical Abstract: Nilgai antelope (Boselaphus tragocamelus), are an exotic species of ungulate in Texas. Native to India, Nepal, and Pakistan, nilgai have expanded into northeast Mexico and much of coastal southern Texas since their introduction in 1924–1949. The presence of nilgai in Mexico and South Texas has complicated the eradication of cattle fever ticks (CFT; Rhipicephalus annulatus and R. microplus). CFT can transmit bovine babesiosis to cattle, which is a serious economic threat to the U.S. cattle industry. With CFT quarantine established in southern Texas, ranches with infested cattle have to comply with eradication requirements. Wildlife can hinder management efforts because white-tailed deer (Odocoileus virginianus) and nilgai are alternative hosts for CFT. Control methods, such as treated baits, are available for deer. Nilgai do not respond to bait, which is a major challenge for controlling the spread of CFT. Methods for control of CFT on nilgai are critically needed. One unique aspect of nilgai ecology is their use of communal latrines, or repeated defecation in the same location. The existence of communal gathering areas which nilgai re-visit presents an opportunity for treatment of CFT. We are characterizing the distribution and usage of latrines on ranches in South Texas. We will analyze the density, size, and location of latrines in relation to roads, habitat types, and abundance of nilgai. The results of this study will have important implications for the development of treatment methods for CFT-infested nilgai for eradication of this pest in the U.S.