Does anything raid corvid nests? Yeah, bears!

I’ve talked before about how the claim that crows (and ravens) are “destroying the ecosystem and songbird populations” is mostly unsupported by science.  Breeding plovers and desert tortoises are among the handful of exceptions1,2.  Nevertheless I still see, even in the comment threads of this very blog, people claiming that corvids are out of control and have no predators.  If it wasn’t such a misguided and ultimately dangerous sentiment I might just ¯\_(ツ)_/¯ whenever folks claimed that crows and ravens have no natural predators because those of us who spend even a small amount of time observing them in the summer will know this is anything but true.

Eggs and baby birds are a key summer food source for a ton of animals and, while seeing a downy little gosling in the mouth of an arctic fox makes me cringe a little, knowing a healthy population of breeding birds is helping to sustain a community of predators is the kind of ecological balance that, in the long run, makes my heart sing.

Stillframe from Planet Earth

Stillframe from Planet Earth

Corvids are part of this system too, which means their babies are also getting eaten all the time.  Usually it’s by things like hawks, eagles, owl and racoons but a recent video taken in Alberta shows yet another predator we can bear in mind.  It’s never gonna be fun to see the birds I care about taking a hit like this, but knowing that corvid babies are helping to sustain top predators only deepens my love and appreciation for them.  Predators and prey make the world go round and corvids have the bad ass role of being both.

Photo: Linda Powell

Photo: Linda Powell

Literature cited:

1. Johnson, M. and Oring, L.W. 2002.  Are nest enclosures and effective tool in plover conservation? Waterbirds 25: 184-190

2. Kristin, W.B. and Boarman, W.I. 2003.  Spatial pattern of risk of common raven predation on desert tortoises.  Ecology 84:2432–2443

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Filed under Ecosystem, Raven behavior

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