I would love to have a couple of those dogs.  A friend of mine has some she got in a rescue deal and started doing this with them.  It is neat to see them chase down a coyote.

I have my heifer pairs on a field that has a canal bank on on side.  I have a 2 wire fence around it that must be keeping them out of the field.  Every couple of days I have seen some yotes sitting on the canal bank eyeing the calves.  Can't ever get a good shot at them though.  The yotes must have hit the fence or something because they won't come in the field??