The black-tailed prairie dog is the most widespread prairie dog, ranging from northern Mexico to southern Canada. In the early 1900s, its population was thought to be about 5 billion. When settlers came to the Plains, prairie dogs were seen as pests, their underground towns were destroyed, and the animals were poisoned. With all the changes to the land, the prairie dog population is only one percent of what it once was. Today, the government and landowners practice prairie dog control to balance ranch land with prairie dog habitats. The biggest prairie dog town held 400 million prairie dogs. Black-tailed prairie dogs are 14 to 17 inches long, eat grasses, small plants, and some insects, live in underground tunnels called towns, and were named by French explorers for their barking noise.