Lawn holes

Hi, I've got about 6 or 7 little mounds of soil in my lawn and I'm wondering what's causing them. They are about 3 inches across and have a 1cm hole in the middle of them. Any ideas? thanks

 

Mining bees. these are solitary none stinging useful creatures. Leave them alone and they will soon seal off the tunnels to allow their larva to develop. They do not seem to mind the grass being cut either.

 

they could be worm casts at this time of year. ona dry day brush them away before mowing, and whatever you do...DON'T KILL THE WORMS. They are great for your lawn!!