Tachinid Flies are indeed a gardeners best friend. They are parasitic in their larval life stage of course and their favorite target are major insect pests to the garden. They eat pollen etc but kill pests with their larva. They are not mammal flesh eating flies per se.
I had to laugh about the hairy butt but there must be a reason lololol.
Location: in the garden (even after several hard freezes below 20 degrees). Bliss Dinosaur Ranch, Wyoming/Montana borderlands.