GonaCon Vaccine Booster Field Trial
Baker D.L., J.G. Powers, J.I. Ransom, B.E. McCann, M.W. Oehler, J.E. Bruemmer, N.L. Galloway, D. C. Eckery, and T. M. Nett. 2018. Reimmunization increases contraceptive effectiveness of gonadotropin-releasing hormone vaccine (GonaCon-Equine) in free-ranging horses (Equus caballus): Limitations and side effects. PLoS ONE 13(7): e0201570.
Gelding Effects in a Wild Horse Herd
King, S.R.B., K.A. Schoenecker, and M.J. Cole. 2022. Effect of adult male sterilization on the behavior and social associations of a feral polygynous ungulate: the horse. Applied Animal Behaviour Science 249: 105598.
Esmaeili, S., et al. 2021. Body size and digestive system shape resource selection by ungulates: A cross-taxa test of the forage maturation hypothesis. Ecology Letters 24: 2178-2191.
Schoenecker, K.A., S. Esmaeili, and S.R.B. King. 2023. Seasonal resource selection and movement ecology of free-ranging horses in the western United States. Journal of Wildlife Management 87(2): e22341.
Y-shaped Silicone IUD (Domestic horse trial)
Holyoak, G.R., C.C. Lyman, S. Wang, S.S. Germaine, C.O. Anderson, J.M. Baldrighi, N. Vemula, G.B. Rexabek, and A.J. Kane. 2021. Efficacy of a Y-design intrauterine device as a horse contraceptive. Journal of Wildlife Management 85:1169-1174.
Lyman, C.C., J.M. Baldrighi, C.O. Anderson, S.S. Germaine, A.J. Kane, and G.R. Holyoak. 2021. Modification of O-ring intrauterine devices (IUDs) in mares: contraception without estrus suppression. Animal Reproduction Science 234: 106864.
Wild Horse Infrared Survey Trials
Schoenecker, K.A., P.F. Doherty, J.S. Hourt, and J.P. Romero, J.P. 2018. Testing infrared camera surveys and distance analyses to estimate feral horse abundance in a known population. Wildlife Society Bulletin 42:452-459.
Wild Burro Double-Observer and Infrared Aerial Surveys
Hennig, J.D., K.A. Schoenecker, J.W. Cain, G.W. Roemer, and J.L. Laake. 2022. Accounting for residual heterogeneity in double-observer sightability models to decrease bias in feral burro abundance estimates. Journal of Wildlife Management 2022;e22239.
Wild Horse Population Size from Noninvasive Fecal DNA
Schoenecker, K.A., S.R. King, L.S. Ekernas, and S.J. Oyler‐McCance. 2021. Using fecal DNA and closed‐capture models to estimate feral horse population size. Journal of Wildlife Management 85:1150-1161
King, S.R.B., and K.A. Schoenecker. 2019. Comparison of methods to examine diet of feral horses from noninvasively collected fecal samples. Rangeland Ecology & Management 72:661-666.
King, S.R.B., K.A. Schoenecker and D.J. Manier. 2019. Potential spread of cheatgrass (Bromus tectorum) and other invasive species by feral horses (Equus ferus caballus) in western Colorado. Rangeland Ecology and Management 72(4): 706-710.
SpayVac PZP Vaccine Pasture Trials
Roelle, J.E., S.S. Germaine, A.J. Kane, and B.S. Cade. 2017. Efficacy of SpayVac ® as a contraceptive in feral horses. Wildlife Society Bulletin 41:107-115.
Roelle, J. 2015. Second captive breeding trial to evaluate the efficacy of SpayVac as a wild horse contraceptive. Unpublished USGS Fort Collins Science Center report to BLM.
SpayVac had promising results in the first BLM-funded trials (Roelle et al. 2017), but did not prove to be long-lasting in the second pen trials (Roelle et al. 2015).The following modeling paper was part of the same project, but examined potential effects if there was a hypothetical sterilant type vaccine available:
Roelle, J.E. and S.J. Oyler-McCance. 2015. Potential demographic and genetic effects of a sterilant applied to wild horse mares. US Geological Survey Open-file Report 2015-1045.
Oocyte Growth Factor Vaccine (Domestic Trial)
Davis K.A., K.M. Klohonatz D.S.O. Mora, H.M. Twenter, P.E. Graham, P. Pinedo, D.C. Eckery, and J.E. Bruemmer. 2018. Effects of immunization against bone morphogenetic protein-15 and growth differentiation factor-9 on ovarian function in mares. Animal Reproduction Science 192:69-77.
PopEquus Population Model
Folt, B., Ekernas, L.S., Edmunds, D., Hannon, M., and Schoenecker, K.A. 2023. PopEquus: A Predictive Modeling Tool to Support Management Decisions for Free-roaming Horse Populations, Version 1.0.0: U.S. Geological Survey software release, https://doi.org/10.5066/P9NMRQDG. Link to online access here.
WHB Population Genetics
Publication is in review; not available at this time
Wild Burro PZP Darting
Boyles-Griffin, S. 2021. Applicability and efficiency of PZP on wild burros in northwestern Arizona. Final report from Humane Society of the United States to the BLM, for agreement L16AC00008. (Unpublished; inquire for copy from Paul Griffin if interested)
PZP Vaccine Capsules Development
Final publications in preparation (Lanutti et al. 2021)
PZP Adjuvant Improvement
Final publications in preparation
PZP Pellet Trials (PZP-22)
Rutberg, A., K. Grams, J.W. Turner, and H. Hopkins. 2017. Contraceptive efficacy of priming and boosting does of controlled-release PZP in wild horses. Wildlife Research 44:174-181.
Turner, J.W. 2017. Development of a controlled-release 3-4 year PZP contraceptive vaccine for wild horses. Final report for BLM assistance agreement L10AC20431. University of Toledo, Toledo, Ohio. (Unpublished; inquire for copy from Paul Griffin if interested)
Wild Horse Impacts on Sage Grouse
Coates, P.S., S.T. O’Neil, D. Muñoz, and I. Dwight. 2021. Free-Roaming Horses Adversely Impact Greater Sage-Grouse Population Dynamics in Sagebrush Ecosystems. Journal of Wildlife Management 85:1132-1149.
Muñoz, D.A., P.S. Coates, and M.A. Ricca. 2020. Free-roaming horses disrupt greater sage-grouse lekking activity in the great basin. Journal of Arid Environments 184: 104304.
Wild Horse and Burro Radio Collar Testing
Schoenecker K.A., S.R.B. King, and G.H. Collins. 2020. Evaluation of the impacts of radio-marking devices on feral horses and burros in a captive setting. Human-Wildlife Interactions 14:73-86.
King, S.R.B., and K.A. Schoenecker. 2022. Application of tail transmitters for tracking feral horses as an alternative to radio collars. Wildlife Society Bulletin 46(4): e1338.
Wild Horse Movements on Wyoming Checkerboard Lands
Hennig, J.D., J.D. Scasta, and J.L. Beck. 2018. Spatial ecology observations from feral horses equipped with global positioning system transmitters. Human–Wildlife Interactions 12:75–84.
Hennig, J.D., J.L. Beck, C.J. Gray, and J.D. Scasta. 2020. Temporal overlap among feral horses, cattle, and native ungulates at water sources. Journal of Wildlife Management 85: 1084-1090.
Hennig, J.D., J.L. Beck, C.J. Ducharct, and J.D. Scasta. 2021. Variation in sage-grouse habitat quality metrics across a gradient of feral horse use. Journal of Arid Environments 192:104550
Hennig, J.D., J.D. Scasta, A.C. Pratt, C.P. Wanner, and J.L. Beck. 2022. Habitat selection and space use overlap between feral horses, pronghorn, and greater sage‐grouse in cold arid steppe. Journal of Wildlife Management 2022: e22329
Wild Burro-Vehicle Collisions
Gagnon, J.W., C. Beach, S.C. Sprague, H.P. Nelson, and C.D. Loberger. 2022. Strategies to reduce burro-vehicle collisions in the Lake Pleasant area. SPR-753. Arizona Game and Fish Department (AGFD) report to Arizona Department of Transportation. AGFD, Phoenix, Arizona.
Satellite-based Wild Horse Counts
Final publications in preparation
Wild Horse Riparian Impacts
Kaweck, M.M., J.P. Severson, and K.L. Launchbaugh. 2018. Impacts of wild horses, cattle, and wildlife on riparian areas in Idaho. Rangelands 40:45-52.
Wild Horse Adoption Marketing
Great Lakes Marketing Research. 2016. Wild Horse and Burro Program GLM 15112 Demand and Private Placement Research. Final Report to the BLM.
Off-range Wild Horse Shade / Thermal Requirements
Holcomb, K.E., and C.S. Stull. 2016. Effect of time and weather on preference, frequency, and duration of shade use by horses. Journal of Animal Science 94:1653-1661.
Tubal Ligation (Domestic Trial)
Dini, P., A. Weiland, Y. Boakari, K.E. Scoggin, A. Esteller-Vico, P. Daels, and B.A. Ball. 2021. Use of tubo-ovarian ligation via colpotomy as a potential method for sterilization in mares. Journal of Equine Veterinary Science 104: 103683.
