Originally Posted by Whttail_in_MT
I won't speak for WY, but in MT they're army cutworms and it's adults the bears feed on before the millers return to lower elevations to lay eggs.

https://apps.msuextension.org/montguide/guide.html?sku=MT200005AG

Thanks for posting that.

It's commonly thought, but wrong, here that it is a larvae stage of Army Moth that the Grizzlies are eating. Or at least my dumb azz thought it.

It looks like that's not right and it the adults preparing to lay eggs. That make sense because the bears are rolling rock in daylight to find the treats.

Right now we have a [bleep] load of moths down low and they love to hide in dark places during the day.

Site is a bit "climate" crazy but interesting article about moths and Grizzlies.

Grizzlies and Army Moths

John Burns

I have all the sources.
They can't stop the signal.