Shoot lower then the eyes.. Maybe about 6 inches lower... If you hit it in the chest and front legs you will anchor it for sure.. You might be shooting over it if you aim at the eyes.... I have missed a few by shooting at the eyes with a fox looking directly at me .. Now I shoot lower..
Also put a piece of adhesive velcro...The rough velcro side where you put your cheek on the stock of the gun...Use this as a feeler for your cheek.. This will line you up better at night time.. It's tough shooting at night... Shots in the daytime are so easy but when night comes you will miss them.. Are you using a bobber styk behind the bead of your shotgun bead. If so make sure you do shoot lower since this makes your point of aim higher... If your not using a lighted bobber styk you need too. You need something lit to aim your shotgun at. Remember lower is better when they are in shotgun range. They, bobber styke lights come in the types One you activate by bending but they do freeze when cold weather hits and renders them useless.. They only last a night time. Get the one with the little battery on it... They can be found in the fishing department near the fishing bobbers... Cabelas and Gander, and Basspro, and sometimes Dicks have them... Mount them with a small piece of adhesive velcro. One part on the rib one part on the styk. You can also use a small wire tie if you have a vent rib. I use both to make sure it does not move in transient...