"These unsustainable practices are a waste of taxpayer money and jeopardize the health and safety of wild horses across the West," he said.
BLM officials said they welcomed the recommendations to help in their effort to make the program more cost-effective. Spokesman Tom Gorey said the agency "needs and wants to do a better job" managing horses, but said those advocating an end to all roundups are misguided.
"It appears that our critics want to use the report as a propaganda tool to stop gathers," which the BLM is required to do by law, Gorey said.
"Do the American people and does Congress support changing the law so that BLM would carry out a laissez-faire management policy that would subject horses and burros to mass starvation or dehydration by letting Mother Nature work her will?" he asked in an email to The Associated Press.
Panel members said they found little scientific basis for establishing what BLM considers to be appropriate, ecologically based caps on horse numbers and even less basis for estimating the overall population itself.
"It seems that the national statistics are the product of hundreds of subjective, probably independent, judgments and assumptions by range managers and administrators," the report said.
BLM's current population estimate likely is anywhere from 10 percent to 50 percent short of the true level, the report said.
The number of animals at holding facilities surpassed the estimated number on the range in 10 Western states earlier this year for the first time since President Richard Nixon signed the Free-Roaming Horses and Burros Act of 1971.
The agency averaged removing 8,000 horses from the range annually from 2002 to 2011. Last year, it spent 60 percent of its wild horse budget on holding facilities alone, more than $40 million, the committee said.
Palmer said the public traditionally adopted about 3,000 of the horses annually but that has fallen off in recent years.
"The goal would be to manage horses better on the range so that any numbers that would be taken off would be matched with the adoption demand, which is not the current case."