Natural History of the White-Inyo Range "d0e23306"

True Frogs (Family Ranidae)

Bullfrog,Rana catesbeiana(Shaw, 1802). (Plate 9.10, Map 9.9) 4–8 in (10–20 cm); background color light to dark green, uniform on back with crossbars on legs; conspicuous large eardrum behind eye. Habitat: This frog prefers slow-moving streams and rivers. It is also common in marshes associated with permanent ponds and lakes. Bullfrogs are active both during the day and at night. They are very wary, and when approached they commonly escape by jumping from the bank into the water. Remarks: Bullfrogs are not native to the area. They were originally introduced from the eastern United States to parts of western North America to provide a fresh source of meat. Natural expansion of this frog's range and further introductions have greatly

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Map 9.9

Map 9.10

increased the area in which Bullfrogs live. Unfortunately, they have had a disastrous effect on native amphibians because they prey on them. A large Bullfrog is capable of eating the young and even adults of the native frogs and toads. Red-legged Frogs (R. aurora ) and Foothill Yellow-legged Frogs (R. boylei ) are now extinct in many areas of central California due to the presence of Bullfrogs. In our area, they were recently introduced into the Fish Lake Valley, where Western Toads (Bufo boreas ) were formerly common. During the preparation of this chapter, extensive field work was conducted in the Fish Lake Valley, but no Western Toads were seen. Range: Introduced into the Owens Valley; Fish Lake, Fish Lake Valley; marshes around Salt Works, Saline Valley. References: Moyle (1973).

Localities: California, Inyo Co.: Owens River, 2 mi S Independence. Mono Co.: Fish Slough, 0.4 mi N Inyo County line. Nevada, Esmeralda Co.: Fish Lake.

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Northern Leopard Frog,Rana pipiens (Schreber, 1782). (Plate 9.11, Map 9.10) 2 1/2–4 in (6.25–11.25 cm); background color gray or tan; distinct dark-brown or black spots over back and sides; spots on legs forming bars; pale-colored ridge runs down each side of the back from top of eyelid to hind leg; ventral surface uniformly pale. Habitat: Northern Leopard Frogs occur around permanent ponds and streams. They are active both during the day and at night. This is a wary species that usually jumps into the water when approached. Remarks: Leopard Frogs, which range from Panama to the Northwest Territories, Canada, are the most widely distributed group of frogs in North America. Until recently they were all considered one species. The Northern Leopard Frog is the widest-ranging species currently recognized in this group; it occurs from New Foundland to the western Great Basin. This species' wide range is presumed to be due to major expansions since the recession of the last glacial period, which started 18,000 years ago. Leopard Frogs are commonly used in biology class dissections and laboratories around the country. This practice has led to many introductions of this species where they did not formerly occur. Range: Northern Owens Valley from Big Pine to north of Bishop; may occur further south in the Owens Valley (see ? on Map 9.10); reported from the east side of the White Mountains below Boundary Peak. References: Hillis, Frost, and Wright (1983); Sage and Selander (1979).

Localities: California, Inyo Co.: 1 mi W Big Pine; 4 mi W Bishop (W of study area); 3.2 mi N (UMMZ); 5 mi N (LACM, MVZ); 8 mi S. Nevada, Esmeralda Co.: 7,100 ft, east side of White Mountains below Boundary Peak (UN).