Some drama at the heron rookery this afternoon...

[squirl033]

A bit of an altercation at the Everett marina this afternoon. Watching at the time, I thought maybe this was just a neighbors' squabble, but when I got home and looked on the "big screen", it appears this was something much more sinister. An immature heron seems to have "invaded" a neighboring nest with young chicks, perhaps with an eye toward an easy meal, and the parent is having none of it. Do herons prey on young chicks of their own kind? In any case, the adult seems to have won this argument, fortunately for the chicks at its feet...

 

[Bill Anderson]

I sent a link to your photos to one of my contacts at the Washington state Dept. of Fish & Wildlife and received this reply:

Interesting. The fledged chick looks much bigger than the chicks in the nest. Herons lay their eggs asynchonically, so it’s common to have the first bird hatched be bigger and older than the last one hatched and have the older chick kill the younger ones. Especially in years where food is scarce. The bird that was ousted by the adult looks too old to be a sibling, but that’s one possibility. The other explanation is that it’s trying to prey on a neighboring nest’s chicks, as you suggest. A meal is a meal, especially when you aren’t very good at foraging for yourself yet, so I’d say yes, they will eat chicks of their own species if they can get to them.

 

[squirl033]

I sent a link to your photos to one of my contacts at the Washington state Dept. of Fish & Wildlife and received this reply:

Interesting. The fledged chick looks much bigger than the chicks in the nest. Herons lay their eggs asynchonically, so it’s common to have the first bird hatched be bigger and older than the last one hatched and have the older chick kill the younger ones. Especially in years where food is scarce. The bird that was ousted by the adult looks too old to be a sibling, but that’s one possibility. The other explanation is that it’s trying to prey on a neighboring nest’s chicks, as you suggest. A meal is a meal, especially when you aren’t very good at foraging for yourself yet, so I’d say yes, they will eat chicks of their own species if they can get to them.

I'm quite sure the fledgling is not a sibling. Based on its size, it's a good 4-6 weeks older than the little ones. Herons space their eggs apart, but by days, not weeks. Those nests are very close together, and everything I saw points to the intruder being an older juvenile from a neighboring nest, looking for an easy meal. The adult had left its nest briefly, and the older juvenile moved in, but the adult came back before it could take one of the little chicks. The kerfuffle ensued, and the adult appeared to successfully fend off the juvenile's attack... I've always felt that herons are godless killing machines that will eat anything they can catch and swallow; this just reinforces that perception!