I suspect that no one has answered because of the quality of the picture....it's very difficult to peer into it and see anything useful. Could you try again? Maybe a different time of day so that there's plenty of light on the subject. I can't tell if it's something coming from below the soil surface or on top!

In the meantime, you could try something: Fill a bucket with water and a few squirts of dish soap. Slowly pour this into the soil in a couple of places....doesn't have to be right on top of those mounds. After you've drenched one spot, wait and see if anything comes up to the surface to escape the mildly soapy water.

I used to scout for mole crickets that way, but all kinds of critters could come out.