caterpillar poop

Here are some pictures for size reference. All poop seems to be of equal dryness. Yup, this is a poop post.

The little poop on the right side is from the hornworms that have been hanging out in my evening primrose. That's what I've got pictured with the tape measure.

I think the giant poop on the left fell out of a birch tree. There was some scattered around on a pallet under the tree. The only things growing on the ground are bracken and a little bit of spreading dogbane, none of which seems munched on.

I think we might get tomato hornworms here sometimes, but I've never seen one. I saw one where I used to live, a few hours away. Here, I've only ever seen these sphinx moth hornworms, and never much bigger than this one. I wonder what's out there.

It looks like poop, but could it be something else?

From this article that might be owl pellets or even bat guano.

https://www.wildlifetrusts.org/wildlife/how-identify/identify-poo

I wonder what other folks on the forum think that is.

Thanks, Anne. To me it definitely looks like caterpillar poop. There are no bones or insect bits in it like there would be in owl pellets. Bat guano just looks like mouse poop, and if there was bat guano this size it would raise the question of what kind of freakish giant bat left this?! We don't have big bats here.

I wasn't really looking for an ID so much as just marveling at how big the caterpillar must be.

Looks like you are right:



This is interesting:

agreed! classic, barrel-shaped caterpillar poop.

It could be a white-lined sphinx moth caterpillar. The moth is so big it almost looks like a hummingbird.

May Lotito wrote:It could be a white-lined sphinx moth caterpillar. The moth is so big it almost looks like a hummingbird.

Yup, that's probably what's in the picture I posted.

Wow, giant caterpillar poop! I'm estimating the poop is about 2 1/2 to 3 times the size of the pictured caterpillar. This would make the pooper about 20cm or 8 inches! According to Birds and Blooms website they grow to about 4-5 inches, which I think is plenty big enough.
The Pupa is amusing, it has a little handle:



Apparently that is the pupa-mouthpieces of the adult moth.