For a quick estimate, convert the livestock AUMs to wild horses and add the result to the AML.
The 100 horses allowed by plan require 1,200 AUMs per year. The HMA covers 99,736 total acres, including 92,373 BLM (public) acres.
The eight permittees receive a total of 13,597 AUMs per year according to Table 2.
The Allotment Master Report indicates a forage allocation of 13,892 AUMs per year across the two allotments. Both are in the Improve category and contain a total of 92,371 public acres.
The forage assigned to livestock, based on data in the EA, would support an additional 13,597 ÷ 12 = 1,133 wild horses, for a True AML of 100 + 1,133 = 1,233. This is the number of animals the HMA could support if it was managed principally for wild horses, as specified in the original statute.
The current population of 270 is well within this range, so there are no excess horses in the HMA and there is no need for a roundup or fertility control program.
The 1,133 horses displaced from the HMA by permitted grazing represent 2.3% of the 50,000 animals in off-range holding.
The current AML corresponds to about 8% of the total authorized forage, neglecting wildlife, meaning the HMA is managed principally for livestock.
Forage availability in this area is very high, about 160 AUMs per year per thousand acres, which would support a stocking rate of 13 wild horses per thousand acres!
The target rate across all HMAs is one wild horse per thousand acres.
AMLs and stocking rates are low relative to the available resources because the bureaucrats put ranching interests far above those of the horses.
The advocates would have you believe that Herd Management Area Plans (HMAPs) are the answer to wild horse mismanagement, but until the Resource Management Plans are changed, they can only prolong it.
Confine the ranchers to their base properties, including those who secure grazing preference with water rights, and let them pay market rates to feed their animals.