05-06-2012, 02:37 PM
I have been filming a American Robins nest with chicks. I discoved the nest about three days ago. I have noticed that the mother or father will fly in with a worm or some other grub and feed it to the waiting chicks. He/she will apparently wait around for a couple of minutes and before leaving the nest he/she will take something from one of the chicks and seem to swallow whatever it is. I have a picture of it below. Is this some kind of waist or what. Can anyone help? Thanks ahead of time.
05-06-2012, 05:25 PM
Great document image! That is the parent removing the fecal sac, which is a thin membrane containing the young chick's waste. Many birds do this to avoid the nest being overflowed with waste...as I'm sure you've witnessed, these young ones have a voracious appetite!! I'm not convinced that the parent swallowed it though. Most likely flew off with it and dropped it a good ways away (to avoid giving clues to potential predators). Here's a Great-crested Flycatcher about to fly off with one: