The weirdest part of this is that if the poles flip, birds will wind up flying North for the Winter.
Well, that depends on what hemisphere they ordinarily navigate in, but not just birds. Bees will be disoriented as well, but with the shorter lifespans, anyway, the survivors will figure it out and subsequent generations will only know the new field orientation.
The serious question arises how many marine animal species rely on magnetism for navigation as well.