titanmelon said:
2a What to do with all these tags ?

< SNIP >
Should I add them to tag group:species?

tag group:species is intended as a quick guide, not an exhaustive listing. SOme of those obviously need implications to bird. With the possible exception of Kingfisher (which probably has an undertagging issue), I wouldn't list anything under about 30 to 50 posts.

So I'd add Blue jay, Cardinal, Magpie and Eurasian Magpie (those two are missing from your list), but I'd cut African Fish Eagle, Indochinese_green_magpie, and all the "tit" subentries (Tit is already there, it's just under the aliased no-pparentheses version).