Not to be rude, but why? Even if the red dot scope has no eye relief you will still need to center the dot within the scope. This will cause you to"aim" and when it comes to bird hunting you "point and shoot." I'm not sure if you have eye sight problems and are thinking that a scope might help you be able to pick up on a bird better but when I'm wingshooting I typically don't have a 'focused' eye on the target (everybody shoots differently though). If eye sight IS your problem and you're having difficulties seeing the birds I suggest two options. 1) IF you wear glasses andyou have bi-focals, ditch them for a regular pair of glasses OR 2) buy a pair of full sized prescription shooting glasses (regardless of whether or not you wear bi-focals). The full size lense will help out a lot! Note: This is based only on the assumption that you wear glasses and/or bi-focals. I'm giving you these pointers based on my experiences with small shooting glasses vs. 'full-sized' and my dad's experience with going from bi-focals to prescription shooting glasses with no bi-focals.
I'd like to hear more info for your reasoning!