The person in question is also not a native speaker, as the language involved is English.
It would be interesting to know whether their editorial policy follows any textbook of English usage, even if it turned out to be an American English one rather than as laid down by the native speakers. When I was at school Fowler's Modern English Usage was the usual reference work, but somehow I don't seem to have kept up with whose authority is generally acknowledged since I left.
Personally I capitalise component parts of bird and mammal names (not to mention butterflies, moths and the Odonata) in exactly the same way, and utilise hyphens to aid precision, hence:
Lesser Black-backed Gull
Thirteen-lined Ground Squirrel (don't ask me why I don't use hyphens for Ground-, Tree-, Flying-, Rope- or any other squirrel. I just don't. BTW the hyphens immediately preceding all indicate that something comes after the word, not that hyphens are required between the adjective and the noun.)
Brown Hairstreak
Black-tailed Skimmer
Its a minefield. Actually that should be mine-field but the contraction is in general use. (I mean use generally, not just by Generals. I hope that's clear.)
John 8-P