The pre-gather population in the Frisco HMA, currently subject to a roundup, was thought to be around 250 wild horses. The HMA covers 60,367 acres in western Utah and has an AML of 60.
The horses allowed by plan require 720 AUMs per year. The stocking rate allowed by plan is one wild horse per thousand acres.
The pre-gather population, corresponding roughly to 4X AML, required 3,000 AUMs per year with a stocking rate that’s four times higher than the standard.
There were 190 excess horses on the HMA when the gather started. The need for this and other management actions, such as the application of PZP, is obvious.
The HMA intersects four grazing allotments. The table in Section 3.2 of the Final EA for wild horse roundups in the Conger and Frisco HMAs provides allotment sizes, grazing seasons and permitted AUMs. A map showing the allotments relative to the HMA was not provided.
Although cattle and sheep are allowed by permit, the calculations are based on cow/calf pairs only, for a direct comparison to wild horses. The resource requirements of wild horses and cow/calf pairs are said to be equivalent.
The amount of Red Rock land falling inside the HMA is 20,769 × .08 = 1,662 acres.
The estimated forage available to Red Rock cattle inside the HMA is 801 × .08 = 64 AUMs per year, assuming the resource is evenly distributed across the parcel.
The total estimated land and forage available to livestock inside the HMA, computed as the sum of four components, are 54,483 acres and 2,959 AUMs per year, respectively.
Roughly ten percent of the HMA is free of privately owned livestock.
The Red Rock permittee would have to place 32 cow/calf pairs inside the HMA to graze off 64 AUMs in two months. The stocking rate allowed by plan is 19.3 cow/calf pairs per thousand acres on that allotment. It’s a concentrated animal feeding operation (CAFO) on public lands.
The stocking rates (densities) on the other three allotments are six to seven times higher than that allowed for wild horses in the HMA.
The total estimated number of cow/calf pairs inside the HMA, computed as the sum of four components, is 394. The estimated stocking rate allowed by plan inside the HMA is 394 ÷ 54,483 × 1,000 = 7.2 cow/calf pairs per thousand acres. The weighted average grazing season is 2,959 ÷ 394 = 7.5 months.
These management indicators are compared in the following charts.
The HMA is managed primarily for livestock, with the horses receiving just 20% of the total authorized forage (excluding wildlife). Sixty wild horses compared to 394 cow/calf pairs, on land set aside for wild horses.
Curiously, the HMA has a Herd Management Area Plan, developed in 2012.
The forage allocated to livestock would support an additional 247 wild horses, for a true AML of 307 (2,959 ÷ 12). There were no excess horses on the HMA when the roundup started and there is no justification for a fertility control program.