Jill, I am wondering if your pest is a larger animal, such as, a deer, rabbit, or groundhog.  The black spots on the leaf in your picture may be aphids but it isn't clear whether they are alive.  Even if they are aphids, the damage doesn't match the sucking leaf damage expected from an aphid.  I would suggest that you explore using a deer repellent which may also work on rabbits and groundhogs.  There are various products sold as deer repellents, such as, Liquid Fence, and actual fencing, and ultrasonic devices.  If you see insects other than the black spots on the one leaf in your picture, please send another picture so we can perhaps give you further guidance in controlling them.