Possible Clues:

• House that's for the birds
• There's nothing for it but flying there
• 'Ay, there's flying by way of R in here (6)'
• Place where birds are kept
• Bird cage
• Building for keeping birds
• Birdcage
• They all fly in there by way of the inside of a ray
• Feature of some zoos
• A verbose leader from The Chronicle needs no introduction, as it's for the birds