BirdSite  a catalog of media for birds worldwide

I realize this site is international and that means a LOT of species, but is there any way to see what isn't represented in a specific family or subset? If someone wanted to try and fill in missing species, especially the common stuff, is there an easy way to figure out what is needed?

I might be able to make a list for the North American birds. That is the only "full" taxonomy we have so far. So far I haven't found a free list for the rest of the world.

It might take me some time to work it up. Too much going on at home right now. In the meantime, thanks for posting!