What sort of animal/creature would fill the job of Birds in an ecosystem that otherwise, had "earth-like" stand ins? Larger than us "humans" - beasts of burden, small and large game, fish, the "normal" amount of bugs (while this is a worldwide environment, we're largely on something vaguely analogous to the US west coast - somewhere between San Fran and Seattle latitude, on the coast).
There are no birds - so what would fill that ecological niche?
EDIT: WOW - some GREAT answers - flying lizards (that just never evolved feathers), flying mammals, flying fish - bats and leaping geckos and lungfish everywhere!
FWIW: this was a "never evolved birds" situation - but there are flowering plants, so I needed to figure out how to a) keep down the bug population and b) move seeds. Lots of mammals for both - but the "distance" thing was flumoxing me. Bats and lizard equivalents make a lot of sense.