Wildlife Spotting

I believe this to be either a Meadow Vole, Prairie Vole or possibly a Southern Bog Lemming. I spotted it about 9 a.m. in a patch of grass just feet away from a marshland pond. It's hair is a mix of dark brown, gray, and a little black... and it was chewing on some of the grass. It did not have pronounced ears like a mouse or rat from what i could see.