One of Nature’s Mysteries to Solve

Hey there!

As you can tell by the few posts we squirrels are managing to get out in a week, we are starting our winder slowdown. Nutmeg and I are thinking we will go on hiatus this week. We’ve done this the last few winters, if you are new to The Squirrel Nutwork.

So here’s a mystery for today, a little something we ran across on the side of a wagon:

Mystery #173

And another view:

Mystery #173

 

Who do you gathered these materials? And why?

Leave me your guesses in the comments. I’ll check back later!

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We had a guess that it might be a field mouse nest. In fact, that’s what we squirrels originally thought. But then Nutmeg and I reviewed the mouse nests we’ve seen compared to bird nests. Mouse nests are almost always grass, or grass and one other material, like moss or sometimes a bit of discarded human material.

Take a look at this nest again.

Wren nest

Grass, pine needles, moss, bits of leaf, the veins of leaves, plastic, the lacy roots on top. This is quite a collection! One bird who collects many materials and really builds more of a nest than it needs, is the wren.

Carolina Wren

We aren’t sure if this was built by a Carolina Wren or a House Wren, so if any of you human readers have a firmer idea than we do, please write to us!

One of Nature’s Mysteries to Solve

Hey there!

Our mystery today comes to us from regular reader, Connie. Thanks, Connie!

Mystery #179

Yes, it’s those little blobs, about the size of a small acorn.

I’ll check back later for your guesses, but if you’d like a hint, scroll down:

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Hint: Connie found these on her pontoon boat.

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One brave reader guessed that these particles were the stuffing from the boat. No, but that was our first guess, too! No mice or insects were burrowing inside. This was deposited on the boat and appears nearly every morning, Connie tells us.

And every morning someone visits the boat.

Great Blue Heron on Lake Audubon Paul Hartke 2016

If the light is a bit too dim for you, here’s another photo.

Great Blue Heron on Lake Audubon

That’s a Great Blue Heron. A very old one, we believe, because his beard–the feathers trailing from his neck–is full. Now we squirrels had heard of owls regurgitating pellets of fur and bones after they eat, but not herons, so we did a bit of research. Turns out herons do as well, and it’s called “casting.”

fish bones in a Great Blue Heron casting

fish bones in a Great Blue Heron casting

If you look closely, this deposit, or regurgitation, contains small fish bones and scales!

Herons also have a throat pouch. When they have young in the nest, they swallow a fish or two and carry them back to the nest and regurgitate them for the young birds. Young birds might do the same if a predator attacks their nest to frighten it away.

Want to learn more about Great Blue Herons? The Cornell Lab of Ornithology has a camera on a heron nest and answers many questions about these birds on their Bird Cam FAQ website.