Video:Great blue herons, the theft works (1 Viewer)

Some time ago I noticed two pairs of great blue herons building nests at the same tree. Once one pair left their half-built nest unguarded. A heron from another nest decided it was a great opportunity to improve his/her own nest. For the next 40 minutes or so the heron made many trips between the nests, stealing sticks. I filmed only part of this activities.

https://m.youtube.com/watch?v=cnmlIGGQEyE

This theft worked for the best of the thief. They now have three cute chicks, while the herons from another nest are still incubating because they had to rebuild the nest from scratch.

I observed a similar behavior in Antarctic, where some kind of penguins stealing stones from their neighbors nests.

Interesting - I always wondered about life in heronries!! Looks like that one pair hasn't learned to stand guard. Maybe next year they will figure it out.

video:Great Blue herons chicks attacking their neighbors

Gretchen said:

Interesting - I always wondered about life in heronries!! Looks like that one pair hasn't learned to stand guard. Maybe next year they will figure it out.

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Because I am not very much of a birder, I used to think that, if birds built the nest and mated, the chicks would hatch. Now I know it is not always the case.

There were four heron nests at the same tree in a very close proximity to each other. I observed all pairs courting and mating, but only one pair succeeded in producing the chicks. Chicks grow up to become very aggressive towards the neighbors

https://www.youtube.com/watch?v=OngMNwAFq18

I think it could be one of the reason that at least one pair failed.
I asked an expert about this kind of behavior, and she told me she personally has never seen such aggressive chicks.

I've heard that even chicks can be aggressive. I believe that some kinds of young herons will throw their siblings out of the nest - but I'm sorry I don't recall the details just now.