Don't worry, this question hasn't been added yet. In the newer update I tried to use a different entity spawning method which overrides the Mo'Creatures spawning and allows the birds to spawn alongside that mod (it would originally conflict and prevent them from spawning). I also removed the config as all the spawns are hardcoded and cannot be edited. I will probably change it back though because I am finding the birds aren't as common as they once were. No idea for the reasoning behind that though.
Thanks so much for getting back to me - and so quickly too :=]
It's quite a relief to know that we haven't broken anything by playing around with the config file, and I imagine the scarcity of the new birds is - as you said - because all of the birds are less common than they were.
I'll keep my eye on this thread, in case you do bring out another release soon.
Thanks again. Great mod! Keep it up!