was once quite common through parts of western Canada until declines started occurring during the 1970s. The population decline is thought to have been caused by pollution drift from the United States falling in the form of acid rain. Many populations of northern leopard frogs have not yet recovered from these declines. Reptiles Northern alligator lizard The northern alligator lizard (Elgaria coerulea) is a medium-sized lizard that occurs on the North American west coast. Northern alligator lizards are medium-sized slender lizards. Adults reach a snout-to-vent length of about and a total length of roughly . They have a distinct skin fold on their sides, separating the keeled scales on the back from the smooth ventral scales. They are brownish in color and often have dark blotches that sometimes blend together into bands. The belly is light gray. The eyes are dark. The northern alligator lizard occurs along the Pacific Coast and in the Rocky Mountains from southern British Columbia through Washington, northern Idaho and western Montana south through Oregon to the coastal range and the Sierra Nevada in central California. Sagebrush lizard The sagebrush lizard (Sceloporus graciosus graciosus) is a common lizard found in mid to high latitudes in the Western United States. It belongs to the genus Sceloporus (spiny lizards) in the reptile family Phrynosomatidae. Named after the sagebrush plants near which it is commonly found, the sagebrush lizard has keeled and spiny scales running along its dorsal surface. In Montana, the lizard is found in the southeast portion of the state. Greater short-horned lizard The mountain short-horned lizard, also called Hernandez's short-horned lizard or the greater short-horned lizard, (Phrynosoma hernandesi) is a diurnal species of phrynosomatid lizard. It is an insectivore, feeding mostly on ants, though will also eat young snakes. The lizards are found throughout the mountain ranges in the western U.S. (as south as Texas) and into Canada. It is found from sea level to over 10,000 feet in elevation. It was formerly classified as Phrynosoma douglassi hernandesi. It was named for Francisco Hernández de Toledo, a Spanish explorer who in 1651 wrote one of the first accounts of horned lizards. Pygmy short-horned lizard Western fence lizard The western fence lizard (Sceloporus occidentalis) is a common lizard of California and the surrounding area. It is also known as the blue-belly. Not all fence lizards have a "blue belly". Smaller sized, immature fence lizards have sand colored