By my count, this preening merganser hen had two dozen chicks (23 here, but one had dived). Normally, a hen lays from 6 to 17 eggs, more commonly between 8 and 12. I had previously seen a brood with 19 chicks, but this crowd was a first. Are all these chicks hers? Might other hens have laid their eggs in her nest?
How about a blended family? I think I’m seeing two slightly different sizes of ducklings. The duck may have stolen a brood, or the other mother may have met her demise and her brood just latched on to an available flock.
Carlo, I would buy that explanation. My first reaction when seeing this brood was: Ouch, producing this crowd must have hurt. However, the hen in the picture probably did not produce them all. In addition to nest parasitization, a more likely source of the extras is adoption.
Great pictures Alistair.
Might this be a situation where one bird is babysitting 2 or more broods? I have seen this behaviour in numerous species.
Mary Kate
Mary Kate, that is an interesting speculation. I think its validity would depend upon a merganser hen being able to distinguish its own chicks from those of another hen’s. Some birds (penguins) can do this (by odour). While I don’t know, I doubt if a merganser could reliably make such a distinction.