We have a nest in the pine tree outside our kitchen window (southern California), probably Costa's or Anna's Hummingbird, we have a lot of both and the females look alike to me. I think the eggs hatched yesterday because Mama is spending way more time now flying around and coming back and sticking her beak down into the nest so I presume she is feeding the babies. I can't see down into the nest so my question is, about how long will it be before the babies will be big enough to be visible sticking their heads out?