They’ve achieved zero population growth in two years, according to a story by KLAS News of Las Vegas, and are now letting the herd die off.
Darting begins when a mare is as young as 10 months old, boosters continue every 8 to 12 months, and then after five to seven years, the mare can no longer reproduce.
The program is sponsored by the Campaign Against America’s Wild Horses.
Western Horse Watchers Association 