White-tailed Deer, Nilgai, and Cattle Grazing Interactions

Non-native animals often threaten the productivity of native rangelands. Nilgai, native to India, are one such large herbivore. First, nilgai compete for food with white-tailed deer and cattle. This becomes a major problem during periods of drought when food is scarce. Second, nilgai are alternative hosts of cattle fever ticks, which carry the deadly cattle disease – Texas Cattle Fever (A.K.A. bovine babesiosis), which is a significant threat to the U.S. cattle industry.

On the forage competition front, East Foundation and its research partners conduct extensive vegetation sampling across its four largest properties – the San Antonio Viejo, El Sauz, Santa Rosa, and Buena Vista ranches. Plant (both grass and forb) biomass and diversity are determined, from which annual estimates of grazing intensity and forage standing crop (available pant material) are known. Concurrent analysis of animal tissues (blood, hair, and dung) allow for the reconstruction of animal diets to determine diet overlap and assess competition. An unexpected outcome was the finding that during periods of drought nilgai diets are more like white-tailed deer than cattle.

Thus, nilgai are more likely to compete with deer for woody plants than with cattle for grass during dry times. Efforts to better understand these and other foraging interactions continue.

With regards to cattle fever ticks and nilgai, East Foundation has partnered with other organizations and government agencies to answer critical questions, mainly aimed at developing methods to treat ticks on nilgai. Some of these include:

  • How far do nilgai move? How large of an area do nilgai use?
  • What time of day are nilgai most active?
  • Do nilgai attractants exist?
  • How often do nilgai cross through holes in fences?
  • Why do nilgai use latrines (large dung piles)?
  • Can you determine the age of a nilgai from its teeth?

East Foundation is committed to using science and state-of-the art tools to provide solutions to problems threatening native rangelands.

For more information or questions about this project contact Andrea Montalvo at amontalvo@eastfoundation.net.

Related Publications

Management Bulletin No. 2: Solving the Mystery of How to Treat Nilgai for Cattle Fever Ticks

Full Text June 2020

Lisa D. Zoromski, Randy W. DeYoung, John A. Goolsby, Aaron M. Foley, J. Alfonso Ortega-S., David G. Hewitt, And Landon R. Schofield

Suitability of NDVI and OSAVI as Estimators of Green Biomass and Coverage in a Semi-arid Rangeland

Full Text August 2018

Rachel R. Fern, Elliott A. Foxley, Andrea Bruno, and Michael L. Morrison

Nilgai Antelope in South Texas: Direct and Indirect Impacts on Cattle and White-tailed Deer

Full Text January 2018

Aaron Foley, Tim Fulbright, Alfonso Ortega-S., David Hewitt, Stacy Hines-Adams, and Alfonso Ortega-S., Jr

White-tailed Deer, Cattle, and Nilgai Sharing the Landscape

Full Text December 2017

Timothy E. Fulbright, J. Alfonso Ortega-S, David G. Hewitt, Thomas W. Boutton, Alfonso Ortega-S Jr.

Movement Patterns of Nilgai Antelope in South Texas: Implications for Cattle Fever Tick Management

Full Text August 2017

Aaron M. Foley, John A. Goolsby, Alfonso Ortega-S, Jr., J. Alfonso Ortega-S., A. Pérez de León, Nirbhay K. Singh, Andy Schwartz, Dee Ellis, David G. Hewitt, and Tyler A. Campbell

Comparative Daily Activity Patterns of Nilgai (Boselaphus tragocamelus) and White-tailed Deer (Odocoileus virginianus) in South Texas

Full Text July 2017

Nirbhay K. Singh, John A. Goolsby, Alfonso Ortega-S., Jr., David G. Hewitt, Tyler A. Campbell, and Adalberto Pérez de León

Comparison of Chemical Attractants Against Dung Beetles and Application for Rangeland and Animal Health

Full Text June 2017

J. A. Goolsby, N. K. Singh, D. B. Thomas, A. Ortega-S. Jr, D. G. Hewitt, T. A. Campbell, and A. Pérez de León

Comparison of Natural and Artificial Odor Lures for Nilgai (Boselaphus tragocamelus) and White-tailed Deer (Odocoileus virginianus) in South Texas: Developing Treatment for Cattle Fever Tick Eradication

Full Text May 2017

John A. Goolsby, Nirbhay K. Singh, Alfonso Ortega-S Jr., David G. Hewitt, Tyler A. Campbell, David Wester, and Adalberto A. Pérez de León

Cattle, Deer, and Nilgai Interactions

Full Text August 2016

Stacy Lynn Hines

Effects of Depth and Duration of Burial on Tanglehead (Heteropogon contortus) Seed Viability and Germination in Southern Texas

Full Text March 2016

Joshua L. Grass, Aaron D. Tjelmeland, Forrest S. Smith, Scott L. Mitchell, Sandra Rideout-Hanzak, John Lloyd-Reilley, Shelly D. Maher, and David B. Wester