I understand that bears have sensitive noses. Can anyone tell me if they would try to get into a barn to get horse feed that was closed up in a bin?
Yes. This summer a black bear pulled a solid wooden sliding barn door straight off the front of my barn to get into a closed metal garbage can full of chicken scratch. He appeared to favor the black oil sunflower seeds, as he left the cracked corn behind. We hot wired the barn with a ridiculously large charger and that ended his summer visits.
Weasels were described to me as "furry hotdogs with teeth". I had a hard time getting that image out of my mind ....Well, if your chickens will have a run, well-installed hardware cloth on a solid frame, with a buried skirt and a solid roof, goes a long way to keeping out foxes, coyotes, and raccoons, and hot wire around the outside of that is helpful for the bigger visitors. Minks/weasels can exploit even the smallest holes and I'm not sure there's a fool-proof way to avoid them if they're determined.