I read up on this earlier in the year in the book I'm not 100% sure but If its under water then you can place the trap infront of the cubby but if its out of the water it must be in a established waterway so like on the bank I'm guessing and the trap must be back 7" from the opening. Don't quote me I'd double check the booklet you get with your hunting tags there is a section just on cubby holes.