There are no grubs this time of year. They are probably looking for worms. Moles, too. The pesticide industry tells you that moles eat grubs so you'll buy their stuff. Moles eat worms as their main course. They'll eat grubs if they find them but the are looking for worms. The pesticide industry can't sell you stuff to kill worms so they tell you that you have to spend a hundred dollars a year on Milky Spores to kill grubs that aren't there.
Grubs turn into japanese beetles which then go after grape vines. I hates them bad.