ooh this is really cool!!! one question tho- why do birrin lose their fuzz as they age? i think you said babies had it to protect themselves from parasites, but why would that stop being beneficial? do the parasites only feed on babies?
This mention of the Northern Reclamation has me interested in Birrin geopolitics. I'd love to see a map of all the countries on their world. Should we expect to ever see something along these lines?
While I love your arts and depiction of an alien species, I fail to imagine a head-mounted fun above the head for the same reason as human.
That said their neck look much more robust (what with the big carnivore mouth) and their less flexible/agile body might make it work it for such specie. It look easier to aim than their main weapon.