Bees will attract pests, so you have to deal with it. The key threats here are: mice (restrict access during winter), birds (some people use netting during winter), bears (not where we are), hornets, ants (restrict access), but the most important pest is the varroa mite. There are several effective of none-pesticide methods, here are some: http://www.waldeneffect.org/blog/Treating_varroa_mites_organ...