I'm trying to remember a book I read when I was a young teenager, so early 90s but it could have been published before that. It definitely wouldn't have been published after 1998 though. It was a fantasy novel and the cover was light blue, and was of some mountains and maybe a person looking down into a cave or a valley. There were wyrms/firewyrms trapped in a cave, maybe they were blind? There was a palace with a female character, and a male character who was possibly a wizard or had magic and a close bond with a hoopoe bird (could he talk?). The female character may have also had a bonded bird. I've googled and searched for all I can think of but it's driving me crazy! Maybe I made it up? Can anyone help?!