Ravens and penguin eggs

A couple of years ago I was speaking with researchers who told me that Phillip Island’s Little Ravens were eating penguin eggs.

 

Little Raven (Corvus mellori)
1/1250, f/10, ISO 800

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I was driving around the Summerland coast at the weekend and every so often flocks of Little Ravens would emerge from the long grass; the penguins are breeding and I guess the ravens were foraging.

Corvid species are extremely intelligent and it was noticed that they were congregating at the island during the penguin breeding season – they had learned how to find Little Penguin eggs. Researchers from Phillip Island Nature Park and Deakin University banded the ravens and used remote cameras to study their habits. It was discovered that Little Ravens would either dig through the roof of a penguin’s burrow to access the eggs, or attack from the entrance of the burrow. In both cases they would carry out a sustained attack until the adult penguin could no longer protect the nest.

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Little Penguin (Eudyptula minor)

 

Little Ravens attack burrows from the entrance when the entrances are large or from the roof if the soil layer is thin. Little Penguins become exhausted by the sustained attacks that can continue over several days.

The penguin in the image above looks aggressive but was actually in the process of preening when I captured this stretch and yawn.

I’m not sure how far the study has progressed but my understanding is that some eggs would be baited enough to cause the predators to become unwell but not enough to kill them. It was hoped that this will reduce predation of penguin eggs and provide a strategy for reducing the impact of corvids predating other burrow-nesting species across the world.

Happy birding

Kim

 

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