In 2007 bighorn sheep from Sula Montana were released in American fork Canyon. These sheep were brought in to supplement sheep that had been released in 2001 from Canada. In 2009 these sheep began to suffer from a pnuemonia out break, just like sheep on Goslin mountain that had come from the same Sula Montana source herd. By spring of 2013 the remaining sheep from this herd was hanging out in the foothills licking salt from the side of the road near a golf course. This same behavior has been seen in Thompson Falls Montana in bighorn sheep, along with deer in Utah. Bighorns in Wyoming that were declining used to make long treks to get to minerals that they needed.
The golf course near were the sheep hang out did not exist prior to 2001, and was just being developed in 2003. In 2006 several areas around the golf course appear to have been treated with herbicides. And in 2013 appear to still be being treated. Images of this can be seen below. Besides the golf course a neighborhood and water tanks went in on the hill side as well.
In the spring of 2013 the Utah DWR authorized a hunt for a bighorn sheep near Walsburg Utah after a ewe sheep had been hit on the road. This area is about 7 miles as the crow flies from prove peak, and 15 miles from the mouth of American fork canyon. No other sheep besides the ewe were found. The ewe was hit crossing the highway in an area that had magnesium chloride deposits on it, and was only a short distance from were sheep herders had just placed their salt licks. The hunt was to prevent bighorns from mingling with domestic sheep.