After losing one of deer to a griz last year we decided to run string with cans around.....we also put rope around the meat pole with a propane tree light burning on low....we put our step ladder with a 5gal pail full of cans on top and tied the ladder to the rope perimeter....the night we lost one it was raining hard and the dog had snuck into the tent to escape the rain...the cans were enough to alert the dog and every night the griz came back we got up and let off a few shotgun blasts..we also had a trail cam set up away from camp on the trail into camp...the video almost every night started with the bear causing the camera to turn on, followed by dog barking followed by shotgun blasts...the griz came back every night but 1 so it was an ongoing battle