Looking for recommendations on what to purchase for attempting to eliminate pest crows invading my farm (and yes, this is legal where I live). They are damaging my crops, eating feed meant for our livestock, harassing our livestock and causing property damage. I've tried scarecrows, reflective tape, netting and noise control to no avail. I don't have a great shot but should be able to get pretty close (within 30 yards I'd guess). Thank you.