“Groundhogs” are woodchucks, also known as the Eastern Woodchuck. They are marmots and are the 3rd largest rodentia in the US (beavers are the largest and porcupine the second largest). Unfortunately for the woodchuck, they are considered nuisance species and are readily shot by farmers. They are burrowers, and most farmers dislike their dens, which are frequently thought to cause hoofstock to break legs in the holes. (In reality, it doesn’t happen too often. Cows and horses are smarter than that.)
The artist is also a wildlife rehabber, and woodchucks are her favorite wildlife to raise and rehabilitate back to the wild. They are charming, stubborn and awesome diggers.