In 1968, BLM proposed three new plans for dealing with the Pryor Mountains Mustang herd: removing but not killing all but 30 to 35 animals and allowing the rest to remain on the range; killing all but 10 to 15 animals and allowing the herd to recover to 30 animals; or allowing the state of Montana to remove all the animals and sell them. In response, Pryor Mountains horse advocates began pushing for a protected sanctuary for these animals. The group contacted ABC News producer Hope Ryden and made her aware of BLM's plans. Ryden visited the range and filmed a news segment which aired on July 11, 1968, on ABC News with Frank Reynolds. ABC News and BLM were deluged with mail protesting the removal of the horses after the segment aired. On August 27, 1968, the Humane Society of the United States successfully sued to stop trapping of the horses. The political landscape shifted dramatically toward protection rather than removal of the horses. On September 9, 1968, Secretary of the Interior Stewart Udall formally established a Pryor Mountains Wild Horse Range of . Montana's senior senator, Mike Mansfield, was so elated that he published Udall's order scrapping the BLM plan in the Congressional Record.