Have a large population of mulies and about 25-30 wild muflon sheep here, both love to run across greens at the most inopportune times. Without a high fence around the entire property both are very difficult to keep off the course. Corey is correct a 300 mag is effective but I prefer the silent hemorrhage method. Although, this method leads to long blood trails and recovery in one of the members yards
Seriously, have heard of using cougar urine around the perimeter of the property, hanging mesh bags full of human hair at their entry/exit trails, there are other commercial products available but I'm skeptical of their efficacy. My wife has purchased just about every deer deterrent spray available for the flowers in our yard and it just seems like salad dressing for them. Elk are another story, once they decide they want to go somewhere hardly anything will stop them. Contact your local department of fish & wildlife to see if they have any suggestions or if you can get a hazing permit or possibly initiate a damage hunt. We create and manage fantastic habitat for them and once they discover the sanctuary it's difficult keeping them out. Good luck.