Oh, many a bird did wake and fly, caroo, caroo, caroo,
Oh, many a bird did wake and fly
To the manger bed with a wandering cry
On Christmas Day in the morning, caroo, caroo, caroo
On Christmas Day in the morning.

this is the best version. I found it on Amazon in
A Child's Christmas Revels. I heard it on an NPR broadcast back in '96 or '97 and never forgot it. This is a very similar recording but back then I heard a live performance as part of some Solstice show.