What could possibly do this?

This morning woke up and looked out to the backyard to find this..

some of these mounds of soil that are piled up on the lawn are larger than a basketball!

The crows hang around because they get the worms off the surface. Something is digging up and making these mounds. No hole in the center or side of the mounds though..

Any idea what this could be?

Should we call animal control?

.