If the initial population was 450 and the goal in ten years was 250, a six percent death rate and zero percent birth rate would be needed:
450 × (1 – .06) ^ 10 = 242
This is nonstop darting for ten years with 100% efficacy. The mares will be sterile and the herd will be ruined, just like Assateague Island.
On the bright side, the advocates may convince the bureaucrats and ranchers of their tenacity and ruthlessness, and the feasibility of nonmotorized removal, breaking the Cattoor monopoly.
Western Horse Watchers Association 