Nyjer seed is less attractive to squirrels compared to other types of bird seed. However, determined squirrels may still attempt to access Nyjer seed feeders. To deter squirrels, use squirrel-proof feeders designed specifically to prevent their access. These feeders often feature mechanisms that block squirrels while allowing birds to feed undisturbed. Additionally, placing feeders away from trees or using baffles can help discourage squirrels and other pests.