Egg Intruder? (1 Viewer)

[Eighterniner]

So every year we've always have robins below our deck, conveniently right under a crack in the wood. This year I couldn't wait to monitor their progress, and a few weeks back, three robin eggs were laid. But, no sign of the mother. For AGES. After a while I made the assumption they were abandoned, possibly infertile, and left them to nature. But today, I decided to check once more, only to find an odd scene. All three eggs were in some way damaged, and a new egg had been put in the nest! I can't seem to figure out what kind it is, and in one angle it almost looks like the new egg also has a crack in it?? And even if it was a parasitic egg, it wouldn't exactly survive, considering the mother dipped and hasn't been seen since. Any clues?

 

[jmepler]

Welcome to birdforum. The odd egg is from a Brown-headed Cowbird. The cowbird is a nest parasite. It is possible that the cowbird had previously laid another egg in the nest and the robins recognized the egg as not theirs. If they removed the cowbird egg, it may have resulted in the cowbird returning the the nest and destroying the robin eggs in an attempt to get the robins to nest again. It would appear that the cowbirds were not successful.

 

[Eighterniner]

Welcome to birdforum. The odd egg is from a Brown-headed Cowbird. The cowbird is a nest parasite. It is possible that the cowbird had previously laid another egg in the nest and the robins recognized the egg as not theirs. If they removed the cowbird egg, it may have resulted in the cowbird returning the the nest and destroying the robin eggs in an attempt to get the robins to nest again. It would appear that the cowbirds were not successful.

Ahh! That makes sense. I've seen a few cowbirds in the yard recently, I never knew they were nest parasites though! Thank you!

 

[KC Foggin]

I cringe when I see a Cowbid at one of my feeders But nature predicts that I just deal with it.

 

[Kits]

Welcome to Birdforum.