The Bureau of Land Management did not fulfil its plan to pull all 188 horses from the 38,000-acre management area on the Montana-Wyoming.
The Cloud Foundation, which has been monitoring the muster, said 11 horses were left on the mountain, including two older mares named Electra and Quelle Colour, that the bureau had slated for removal.
"In place of those horses they are taking young horses from bands already in the pens," the foundation said.
The roundup lasted six days.
The bureau's wild horse and burro specialist made the decision to end the roundup because:
A total of 57 horses and three foals (at their mothers' sides) are to be offered for adoption.
"As we understand it, older horses not adopted will be offered for sale. According to the bureau's recent press release, "most of the rest of the 146 horses that were gathered and evaluated have already been released back onto the horse range".
"The bureau released Cloud and his band first. They left less Image, Rain and Arrow and Cloud Dancer (who is going to be turned out with the young stallion Exhilaration, who lives in the Dryhead desert area).
"The wranglers did a fine job trying to get Cloud and his band out, but because of all they were leaving behind the mares were reluctant to leave and for 10 minutes or more, Cloud snaked his band this way and that while the riders tried to push them out the half mile to the opening of the trap.
"It was a relief to see them finally disappear into the rolling lowland hills and start the long journey back up to their mountaintop.
"The bureau released nearly all the horses who have not been tagged for removal - Bolder and Flint and Cloud's mum with her band, among others.
"The old band stallion Starman, who was to be removed in a previous roundup and had been freeze-branded before advocates convinced the bureau to release him, took off and galloped back to the wild followed by his mare, Rosarita, and their black yearling daughter."
Ginger Kathrens, whose documentaries made Cloud famous, was on her way up the mountain with others to check on the returning horses making the journey of more than 10 miles home.
The foundation is angered that the bureau will not release the stallion Conquistador, nor the other older horses removed from the Forest Service area.
"It is cruel and unnecessary to remove Conquistador, Grumpy and the others. We have made this request of the bureau and they are still saying no."
Kathrens urged supports to work for their return to the wild.
She thanked those who supported the horses, and all wild horses across the west.
"There are many new faces who have joined the work of many organisations to save our wild horses and ensure that we have viable herds into the future.
"We are doing our best to catch up on correspondence and continue work on a 'plan b' for these older horses should we not be successful in lobbying for their return to the wild."