Interspecific prey theft in extant theropod dinosaurs – Ardea vs. Spheniscus

Golly, what a science journal-worthy title! An unnecessarily complicated and grandiloquent Ersatz for a simple “Heron steals penguins’ fish!”

The Tierpark Friedrichsfelde in Berlin has started announcing feeding times a while ago, and the penguin feeding (Humboldt penguins, Spheniscus humboldti) is a huge favorite with many people. And with local Grey herons (Ardea cinerea), obviously, as they stand a not-too-shabby chance at nabbing a few fishes, too. The penguin keepers aren’t stupid, and feed the penguins individually, instead of just tossing the fish into the enclosure. But some penguins love dragging their fishes to their nesting holes and deposit them next to the entrance. And that’s when the herons see their chances.

Here’s the line-up and starting formation:

heron

A penguin couple has stashed two fish at the entrance of their den, and the heron stands a few feet away, trying to figure out how to get at the fish without getting nipped by the powerful penguin beaks.

heron
A quick stab – but the penguins are alert! Although the heron managed to grab a tiny bit of the fish skin, the defenders moved too fast to allow it to get a good grip, and the steal failed.

So, wait some more….

heron
STRIKE!
This time the heron didn’t just uncoil its neck in the heron-typical fish-grabbing motion they use when fishing, but also made full use of its wings to counterbalance the extremely rapid stab for the fish. And succeeded:

heron

But not every attempt is successful, and a determined defense combined with a strategically less inept fish storage location can work miracles. Keeping the fish not that far out and really going after the heron allowed these two penguins to keep their share for a relaxed dinner later on.

heron

heron

Some other birds are also on the scrounge. Not quite as daring in their approach, but then a heron is much bigger than a Humboldt penguin, whereas a Hooded crow is quite a bit less hefty. Still, some fish end up lying around……. and what proper crow would pass such a free meal by?

heron

heron

In the end, all those who were in the enclosure were well fed. Can’t say the same about some of the less daringly minded herons, though – each tree around the penguin pen had quite a few of them perched on top, and many of them stayed hungry. I’ll toss in a few gratuitous pics of them.

heron

I especially like this one:

heron

To wrap this up, below there is an animated gif I made of all the shots of the successful fish-grab. Sorry for the borders; I simply moved the camera so much that I can’t crop any better.

heron

About Heinrich Mallison

I'm a dinosaur biomech guy working at the Museum für Naturkunde Berlin.
This entry was posted in "fish", Aves, Dinosauria, lower vertebrates, Maniraptora, Theropoda, Tierpark Berlin, Zoos. Bookmark the permalink.

2 Responses to Interspecific prey theft in extant theropod dinosaurs – Ardea vs. Spheniscus

  1. Pingback: PaleoNews #13 | An Odyssey of Time

  2. Stephen says:

    Excellent pictures

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