All of the above. In (holy chit!) 50 years in Alaska, I've only ever had two problems with bears on a kill. One black (added to meat pile), and one brown - but it was a young and dumb 2or3 year old , and I talked it off the gut pile, 70 yards or so down-slope from the carcass, which it had chewed a bit on overnight. Once, I overnighted on a couple frozen caribou that i had killed a week before, 8 feet down in snow cave (long story involving overflow, snowdrift, and under-drift "found" drowned/abandoned/salvaged dead snowmachine, and 12 mile walk back to village). On exiting the tunnel next morning I found polar bear tracks 5 feet outside the tunnel entrance. Better than a cup of coffee to wake one up! Besides, I had no coffee.
I don't do that stuff no more - I always have coffee makings... beside- we hunt bears in Alaska. They ain't dumb.
On moose kills, I try to move the meat a minimum of 100 yards from the gut pile before nightfall. More is better!!! Go in locked and cocked, eyeballs out. Bears almost always prefer the gut pile to the meat pile , at least for the first day. By that time you should have the meat gone or moved far away.
Studies have shown that Yellowstone bears LEAVE the park come hunting season for the gut piles.
Good luck. Remember, bear paranoia is over-rated, but just because you are bear-paranoid, doesn't mean they aren't out to get you.
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