What the … ?

4.35 am: I woke up, had to take a leak.
4.37 am: Back in bed. Still got some 3 hours of sleep left.
4.38 am: Something prevents me from finding my zen. Or something. It’s outside. Chirping away like a happy bird. Ow wait, it is a bird. Singing. Actually, it’s a few birds, all singing their own tune.
5.07 am: I’m slightly dozing off… I think they finally stopped singing.

WHY ARE BIRDS UP AND SINGING SO EARLY ??? Shouldn’t they at least wait till sunrise ?