How many wild horses in long-term holding can be explained by the ‘rule of four?’
All of them. A quick estimate of the number of horses cheated out of spot on their home range by privately owned livestock is
27,000 × 4 = 108,000
If you removed domestic livestock from half of the HMAs, you could empty all of the off-range corrals and pastures.
But why stop there? Cattle and sheep belong on private land, not wild horses.