Historical Range in California: Red
Listen to this frog:
A short example
iPhone App
Electronic Field Guide to the
Reptiles and Amphibians of
Southern California
Available Now at the
iTunes App Store. |
|
 |
 |
 |
 |
| |
Adult male, Alpine County |
|
 |
 |
 |
 |
| Adult, Alpine County |
Adult, Alpine County |
Adult, Alpine County |
Adult, Alpine County |
 |
 |
 |
 |
| Adult, Alpine County |
Adult, Alpine County |
Adult, Alpine County |
Adult, Alpine County |
 |
 |
 |
 |
| Adult male, Alpine County |
Adult, Alpine County |
Adult, Alpine County |
Underside of adult showing yellow legs, Alpine County |
|
 |
 |
 |
Congregation of adult frogs, Fresno County. These frogs were discovered on the south-facing slope of a barely ice-free alpine lake (11,000 ft.). They are covered with pollen, wind-blown from lower altitudes, which coated the area.
© Ceal Klingler |
Adult, 11,100 ft., Mono County
© Chris Lima |
Juvenile, Alpine County |
Adult underside, Inyo County
© Todd Battey |
| Breeding Adults, Eggs and Tadpoles |
 |
 |
 |
|
| Calling adult male, Alpine County |
Adults in amplexus, Alpine County |
Eggs |
Mature Tadpole |
More pictures of breeding, eggs, tadpoles, and breeding habitat can be seen here.
|
| Habitat |
 |
 |
 |
 |
| Habitat, Alpine County |
Habitat, 8,800 ft., Alpine County |
Habitat, 8,800 ft., Alpine County |
Habitat, Mono County |
 |
 |
|
|
Habitat, Fresno County
© Vance Vredenburg
|
Habitat, Inyo County © Todd Battey |
|
|
| Short Videos |
 |
 |
 |
 |
| These are four videos of three different male frogs calling during an early summer afternoon in Alpine County. Running water, birds, insects, and an occasional Pacific Treefrog are heard in the background. |
 |
 |
 |
 |
| Several pairs of male and female frogs in amplexus are seen in this video with attempts by other males to steal the females. They are successfully fought off by the amplexing males, usually by a strong kick, but sometimes a long wrestling match ensues. |
Several groups of male frogs are seen during the breeding season chasing and amplexing each other. You can hear release calls in the first few scenes. This behavior continued for hours, so it did not appear that they were mistaking each other for females they could breed with, but that it was some kind of territorial behavior between males. Or they could have been practicing their pouncing skills for when they encountered females in the future. (This is a long video which might take some time to download.) |
Two males are seen during the breeding season chasing and amplexing each other until one leaves and the other begins calling. |
This is a long (2 minute) version of a frog calling in the afternoon Alpine County. |
|
Description |
Size |
| Adults are moderate in size, 1.5 - 3.5 in. long from snout to vent (4.0 - 8.9 cm). |
| Appearance |
| Variable in color - olive, yellowish or brown above, with varying amounts of black or brown markings. Pale orange to yellow below and underneath the hind legs. Indistinct dorsolateral folds. No dark face mask. Smells like garlic when handled. Differs from Rana muscosa by having relatively shorter legs and a significantly different mating call. |
| Voice (Listen) |
| The call is a short and rasping call often accellerated and rising at the end, sometimes preceeded by calls that don't rise at the end. Calls primarily underwater during the day, but may also call at night. This frog has no vocal sacs. |
| Behavior |
| A mountain frog of high elevations. Chiefly diurnal. Usually found close to water. Rarely occurs where predatory fishes have been introduced. Probably spends the winter at the bottom of frozen lakes. Emerges shortly after snow melts. In years of heavy snow, may only be active for about 3 months. Rarely occurs where predatory fishes have been introduced. |
| Diet |
| Eats a variety of terrestrial and aquatic invertebrates and tadpoles. May also consume dead frogs and its own eggs. Frogs tend to sit and wait until they see prey come within range, then they strike, or creep up a little then strike, using their large sticky tongue to catch the prey and bring it into the mouth. |
| Reproduction and Young |
Reproduction is aquatic. Fertilization is external. Mating and egg-laying occurs in water shortly after the snows have melted and adults have emerged from hibernation, which can be any time from May - August. Adults tend to live around the breeding pond, so most do not need to travel to the breeding site.
A cluster of 100 - 350 eggs (average 233) is laid in shallow water and is left unattached in still waters, but may be attached to vegetation in flowing water. Egg-laying sites must be connected to permanent lakes or ponds that do not freeze to the bottom in winter, because the tadpoles overwinter, possibly taking as many as 3 or 4 summers before they transform. |
| Range |
| Historically, Rana sierrae ranged "...from the Diamond Mountains north-east of the Sierra Nevada in Plumas County, California, south through the Sierra Nevada to the type locality, the southern-most locality (Inyo County). In the extreme north-west region of the Sierra Nevada, several populations occur just north of the Feather River, and to the east, there was a population on Mt Rose, north-east of Lake Tahoe in Washoe County, Nevada, but it is now extinct. West of the Sierra Nevada crest, the southern part of the R. sierrae range is bordered by ridges that divide the Middle and South Fork of the Kings River, ranging from Mather Pass to the Monarch Divide. East of the Sierra Nevada crest, R. sierrae occurs in the Glass Mountains just south of Mono Lake (Mono County) and along the east slope of the Sierra Nevada south to the type locality at Matlock Lake (Inyo County)." (Vredenburg, et al, 2007.) |
| Habitat |
Inhabits lakes, ponds, meadow streams, isolated pools, and sunny riverbanks in the Sierra Nevada Mountains. Open stream and lake edges with a gentle slope up to a depth of 5-8 cm. seem to be preferred. Waters that do not freeze to the bottom and which do not dry up are required. (If a body of water used for breeding dries up for just one season, 3 - 4 generations of tadpoles will be destroyed.)
From 984 ft. - over 12,000 ft. elevation (370 - 3,660 m.) |
| Taxonomic Notes |
According to a February, 2008 petition by the Center for Biological Diversity and Pacific Rivers Council to list the Sierra Nevada Mountain Yellow-legged Frog as an Endangered Species, "The mountain yellow-legged frog in the Sierra Nevada is geographically, morphologically and genetically distinct from mountain yellow legged frogs in southern California. It is undisputedly a 'species' under the ESAOs listing criteria and warrants recognition as such."
Vredenburg, V. T., R. Bingham, R. Knapp, J. A. T. Morgan, C. Moritz & D. Wake (2007. Journal of Zoology 271: 361–374) have determined that this taxon consists of two species, which they name Rana muscosa - Sierra Madre Yellow-legged Frog, and Rana sierrae - Sierra Nevada Yellow-legged Frog. More from the CNAH.
In 2008, the Society for the Study of Amphibians and Reptiles recognized two species, Rana muscosa - Southern Mountain Yellow-legged Frog , and Rana sierrae - Sierra Nevada Yellow-legged Frog. |
| Conservation Issues (Conservation Status) |
Endangered and absent from a significant part of its historic range. The decline has been attributed to many factors, including introduced non-native trout, airborne pollution, insufficient snowmelt to fill breeding ponds brought about by climate change, cattle grazing, ozone depletion, pollution from mining, public dumping, and chytrid fungus. Fish introductions have stopped in some areas, such as National Parkland, they continue in others. But while it has been documented that introduced trout are substantially reducing the numbers of the frogs, frogs have also disappeared in one watershed where no trout have been introduced, which suggests multiple causes for their decline.
Researchers have discovered protective bacteria on the skin of wild frogs that have survived the chytrid fungus which they have recreated in the lab and used to kill the fungus. Experiments by Vance Vredenburg with wild frogs have shown some success - a 2011 survey found that the only surviving frogs at one location were those that had been treated with the bacteria in 2010. |
|
|
Taxonomy |
| Family |
Ranidae |
True Frogs |
| Genus |
Rana |
True Frogs |
| Species |
sierrae |
Sierra Nevada Yellow-legged Frog
|
|
Original Description |
Rana muscosa: Camp, 1917 - Univ. California Publ. Zool., Vol. 17, No. 9, p. 118
from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
Rana sierrae:
Vredenburg, V. T., R. Bingham, R. Knapp, J. A. T. Morgan, C. Moritz & D. Wake (2007. Journal of Zoology 271: 361–374)
|
|
Meaning of the Scientific Name |
Rana - Frog - "Rana" probably mimics how the Romans heard their call.
sierrae - refers to the Sierra Nevada Mountains
Taken in part from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz
|
|
Alternate Names |
Rana muscosa - Mountain Yellow-legged Frog
|
|
Related or Similar California Frogs |
Rana aurora
Rana boylii
Rana cascadae
Lithobates catesbeiana
Rana draytonii
Rana muscosa
Lithobates pipiens
Rana pretiosa
Lithobates yavapaiensis
|
|
More Information and References |
Natureserve Explorer
California Dept. of Fish and Game
AmphibiaWeb
Center for Biological Diversity
Dr. Roland Knapp's site
Rescuing a Dying Breed - Saving the Southern California Mountain Yellow-legged Frog
The Mountain Yellow-legged Frog - Can They Be Saved?
Stebbins, Robert C., and McGinnis, Samuel M. Field Guide to Amphibians and Reptiles of California: Revised Edition (California Natural History Guides) University of California Press, 2012.
Stebbins, Robert C. California Amphibians and Reptiles. The University of California Press, 1972.
Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.
Behler, John L., and F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.
Powell, Robert., Joseph T. Collins, and Errol D. Hooper Jr. A Key to Amphibians and Reptiles of the Continental United States and Canada. The University Press of Kansas, 1998.
Bartlett, R. D. & Patricia P. Bartlett. Guide and Reference to the Amphibians of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009.
Elliott, Lang, Carl Gerhardt, and Carlos Davidson. Frogs and Toads of North America, a Comprehensive Guide to their Identification, Behavior, and Calls. Houghton Mifflin Harcourt, 2009.
Lannoo, Michael (Editor). Amphibian Declines: The Conservation Status of United States Species. University of California Press, June 2005.
Wright, Anna. Handbook of Frogs and Toads of the United States and Canada. Cornell University Press, 1949.
Basey, Harold E. Discovering Sierra Reptiles and Amphibians. Yosemite Association and Sequoia Natural History Association, 1976, 1991.
Davidson, Carlos. Booklet to the CD Frog and Toad Calls of the Pacific Coast - Vanishing Voices. Cornell Laboratory of Ornithology, 1995.
Vredenburg, V. T., R. Bingham, R. Knapp, J. A. T. Morgan, C. Moritz & D. Wake (2007. Journal of Zoology 271: 361–374)
|
|
| Conservation Status |
The following status listings come from the Special Animals List which is published by the California Department of Fish and Wildlife.
Notes from the 1/11 Special Animals List:
Rana sierrae
Sierra Nevada yellow-legged frog
1) Federal candidate status refers to all populations that occur north of the Tehachapi Mountains in the Sierra Nevada.
2) Formerly Rana muscosa. Rana muscosa has been split into Rana sierrae, the Sierra Nevada yellow-legged frog, found in the northern and central Sierra Nevada and Rana muscosa, the Sierra Madre yellow-legged frog, found in the southern Sierra Nevada and southern California.
3) Rana sierrae was petitioned to be listed as endangered. It is now a state candidate for listing as threatened or endangered
On 2/2/12 the California Fish and Game Commission voted to list Rana sierrae as Threatened and Rana muscosa as Endangered. Both were formerly listed as Species of Special Concern.
|
Organization
|
Status Listing
|
| U.S. Endangered Species Act (ESA) |
Candidate |
|
| California Endangered Species Act (CESA) |
SCT |
Candidate - Threatened |
| California Department of Fish and Wildlife |
DFG:ST |
Threatened |
| Bureau of Land Management |
None |
|
| USDA Forest Service |
USFS:S |
Sensitive |
| Natureserve Global Conservation Status Ranks |
G1 S1 |
Critically Imperiled |
World Conservation Union - IUCN Red List
|
IUCN:EN |
Endangered |
|
|
|
