The mares were part of a wild horse gather conducted at the Calico Complex between October 1st and October 17th. This action was taken by the Black Rock Field Office to administer fertility control measures and balance ecosystems within Winnemucca District lands.
The Black Rock Field Office intends to release 97 mares that have been administered two doses of a birth control vaccine named GonaCon. These horses will return to their original environment, the Calico Complex Herd Management area, on or approximately December 4, 2023. The general public is encouraged to witness the release and those interested will be guided to viewing points by BLM staff. To join this event, an RSVP with Heather O’Hanlon through email (hohanlon@blm.gov) is required. According to Mandy DeForest, the Field Office Manager, the recent wild horse gathering aimed at implementing fertility control among these horses to achieve ecological equilibrium in Winnemucca District lands.
The Calico Complex comprises four herd management areas where plans were made to gather a total of 761 wild horses. Of these gathered horses, 172 mares were targeted for treatment with a fertility suppressant drug before releasing them back into the complex alongside 209 stallions. Those horses which weren't treated and returned to the complex would be transported to off-range corrals at Palomino Valley Center in Reno for adoption, sales or long-term pasturing. This process was carried out using helicopters as operational aids. Previous wild horse gathers such as that held in September 2022 resulted in more than 860 excess wild horses being removed.
October's gathering was implemented as a measure against disturbance or destruction of public land caused by overpopulation of wild horses in these areas. Under the provisions of the Wild Free-Roaming Horses and Burros Act (1971), removal of these animals from lands unable to support their populations is allowed. As explained in a BLM press release dated November 30, this strategy allows for stabilizing resources and protecting the habitat of species such as sage grouse, pronghorn antelope, bighorn sheep and other wild animals.
