NORTHERN POCKET GOPHER (Thomomys talpoides fossor)
A reddish-brown rodent with long, heavy, front digging claws. When compared to ground squirrels the pocket gopher has a heavier, chunky body and a shorter, thick tail. Has large, furlined cheek pouches. Total length 8½ inches. This group of pocket gophers is widely distributed from the great plains to the Pacific coast. Another subspecies (Thomomys talpoides clusius) occurs rarely in the Park although it is common in the plains and foothills. It resembles fossor except that its fur is brownish-gray.
Spending most of its life under the ground this well equipped excavator digs an amazing labyrinth of tunnels in western soils. It can make well over 200 feet of tunnel in a single night, usually digging down 5 or 6 feet below the surface. The prominent locator signs of the gopher are earthen mounds about 12 inches in diameter and 4 inches above ground level. In the center of the mound is an entrance to his tunnel system. In winter this tough, little rodent moves around above ground under the snow. His digging continues at this time and the excavated earth is pushed out of the ground and into his snow tunnels. When the snow melts the next spring the long, irregular earth cylinders lying on the ground are exposed. This shy, secretive gopher is difficult to see even at his earthen look-out mound, because he rarely exposes himself when intruders are nearby. They are found occasionally in meadows up to timberline.