The cost of these 'feral', as you call them, horses, is due to the fact that they were rounded up from their native ranges by BLM, costing American taxpayers millions of dollars, and now need to be fed, for more millions of dollars. Put them back, and that cost goes away. Less than 2% of the BLM's annual budget is spent applying PZP (porcine zone pellucida) fertility control. Doing more of that would create jobs and reduce population growth. The National Academy of Sciences completed a report, requested by BLM, and concluded that BLM should concentrate on fertility control rather than roundups. That recommendation has been ignored.