CaliforniaHerps.com

A Guide to the Amphibians
and Reptiles of California


Southern Mountain Yellow-legged Frog - Rana muscosa

Camp, 1917

(Formerly Rana muscosa - Mountain Yellow-legged Frog)
Click on a picture for a larger view



Southern Mountain Yellow-legged Frog HabitatHistoric Range in California: Orange:
Rana sierrae: Red



observation link



SoCalHerpsCover
iPhone App
Electronic Field Guide to the
Reptiles and Amphibians of
Southern California
Available Now at the
iTunes App Store.




Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains, Los Angeles County Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Transforming tadpole underwater, San Gabriel Mountains, Los Angeles County
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Juvenile, San Gabriel Mountains,
Los Angeles County
Juveniles, San Gabriel Mountains,
Los Angeles County
Juveniles, San Gabriel Mountains,
Los Angeles County
Juveniles, San Gabriel Mountains,
Los Angeles County
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Adult, San Gabriel Mountains,
Los Angeles County
Juvenile, San Gabriel Mountains,
Los Angeles County
Adult, San Gabriel Mountains,
Los Angeles County
Adult, underwater, San Gabriel Mountains, Los Angeles County
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog eggs Southern Mountain Yellow-legged Frog
Adult, San Gabriel Mountains,
Los Angeles County
Adult, Mt. San Jacinto,
Riverside County@ 2005 Brian Hubbs
Eggs, close-up, part of the captive breeding program at the San Diego Zoo's Center for Conservation and Research for Endangered Species.
© Jeffrey M. Lemm
Sub-adult, San Gabriel Mountains,
Los Angeles County
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Adult frogs, from San Bernardino Mountains stock, part of the captive breeding program at the San Diego Zoo's
Center for Conservation and Research for Endangered Species, courtesy of Jeffrey M. Lemm. Photos © Gary Nafis
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog
Adult frogs, part of the captive breeding program at the San Diego Zoo's Center for Conservation and Research for Endangered Species, courtesy of Jeffrey M. Lemm. Photos © Gary Nafis Juvenile, raised in captivity, part of the captive breeding program at the San Diego Zoo's Center for Conservation and Research for Endangered Species, courtesy of Jeffrey M. Lemm. © Gary Nafis Pair of amplexing adults, part of the captive breeding program at the San Diego Zoo's Center for Conservation and Research for Endangered Species, courtesy of Jeffrey M. Lemm. © Gary Nafis Amplexing adults, part of the captive breeding program at the San Diego Zoo's Center for Conservation and Research for Endangered Species.
© Jeffrey M. Lemm
Habitat
Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Habitat
Habitat, 5,100 ft., San Gabriel Mountains, Los Angeles County
Habitat, 5,200 ft., San Gabriel Mountains, Los Angeles County
Habitat, 5,000 ft., San Gabriel Mountains, Los Angeles County
Habitat, San Gabriel Mountains, Los Angeles County   © William Flaxington
Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Habitat
Habitat, 5,100 ft., San Gabriel Mountains, Los Angeles County Habitat, 5,600 ft., Mt. San Jacinto, Riverside County Habitat, Mt. San Jacinto,
Riverside County
Habitat, 5,300 ft., San Gabriel Mountains, Los Angeles County
Southern Mountain Yellow-legged Frog Habitat Southern Mountain Yellow-legged Frog Sign Southern Mountain Yellow-legged Frog Sign Southern Mountain Yellow-legged Frog Sign
Rana muscosa once inhabited this area high up Mt. Palomar in San Diego County.

National Forest Service signs detailing the attempt to protect a small struggling population of Southern
California Mountain Yellow-legged Frogs on Mt. San Jacinto, Riverside County
Short Videos
Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog Southern Mountain Yellow-legged Frog  
Some of the few last remaining juvenile and adult Southern Mountain Yellow-legged Frogs hang on in a small creek on a sunny summer day in the San Gabriel Mountains.  
Description

Size
Moderate in size. Adults are 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 sierrae by having relatively longer legs and a significantly different mating call.
Voice
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. (You can listen to it online at the Western Soundscape Archive, and on the Lang Elliot and the Carlos Davidson CDs listed below in References.)
Behavior
A mountain frog. Chiefly diurnal. Emerges shortly after snow melts. Usually found in or close to water. Rarely occurs where predatory fishes have been introduced.
Diet
Eats a variety of terrestrial and aquatic invertebrates, including beetles, ants, bees, wasps, flies, and dragonflies. Tadpoles may also be consumed. 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 after high creek waters have subsided, from March - May in the southern California populations. In the southern Sierra Nevada populations, breeding may occur later after the snows melt from May to July.

A cluster of eggs is laid in shallow water and is left unattached in still waters, but may be attached to vegetation in streams.

Tadpoles in the Sierras may overwinter, possibly taking as many as 3 or 4 summers before they transform. There is no information on the larval stage of Southern California populations, but it's possible they could transform their first year.
Range
Formerly Rana muscosa ranged "...from Palomar Mountain in San Diego County through the San Jacinto, San Bernardino and San Gabriel Mountains of Riverside, San Bernardino and Los Angeles counties in southern California. These formed four isolated clusters of montane populations. In addition, the species occurred as an isolated cluster of populations on Breckenridge Mountain, south of the Kern River in Kern County, and in the Sierra Nevada in Tulare, Inyo and Fresno counties, extending north to Mather Pass. The distribution of R. muscosa in the Sierra Nevada is bordered by the crest of Sierra Nevada. No populations occur east of the crest. The mountain ridges that separate the headwaters of the South Fork Kings River from the Middle Fork Kings River, from Mather Pass to the Monarch Divide, form the northern border of the range. ... Rana muscosa is extinct on Palomar and Breckenridge mountains." (Vredenburg, et al, 2007.)
Habitat
Inhabits lakes, ponds, meadow streams, isolated pools, sunny riverbanks in the southern Sierra Nevada Mountians. In the mountains of southern California, inhabits rocky streams in narrow canyons and in the chaparral belt.
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 in Southern California and the southern Sierra Nevada Mountains, where it is absent from most of its historic range. Once thought to be extinct in the San Bernardino Mountains until a small population was discovered. Considered extinct on Breckenridge Mountain and Mt. Palomar. Only a few creeks have been found with frogs in the San Gabriel, San Bernardino, and San Jacinto mountains. This decline has been attributed to many factors, including bullfrogs, introduced non-native trout, airborne pollution, cattle grazing, ozone depletion, mining pollution, off road vehicle disturbance, public dumping, chytrid fungus, fires, and excessive flooding.

In June, 2009, biologists from the U.S. Geological Survey and scientists from the San Diego Natural History Museum retraced a 1908 expedition through the San Jacinto Wilderness near Idyllwild and re-discovered a population of frogs in two creeks 2.5 miles apart.

The San Diego Zoo, along with the California Dept. of Fish and Game, the U.S. Fish and Wildlife Service, the U. S. Forest Service, and the U.S. Geological Survey, has developed a Mountain Yellow-legged Frog Recovery Program, a captive breeding and translocation plan for the only remaining frogs known from the San Bernardino Mountains. In August of 2006, 75 tadpoles were removed from a drying creek bed in the San Bernardino Mountains and transferred to the program. They began planting eggs into the wild in April 2010.




Taxonomy
Family Ranidae True Frogs Rafinesque, 1814
Genus Rana True Frogs Linnaeus, 1758
Species muscosa Southern Mountain Yellow-legged Frog

Camp, 1917
Original Description
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

Meaning of the Scientific Name

Rana - Frog - "Rana" probably mimics how the Romans heard their call.
muscosa -
Latin - mossy, full of moss- referring to the lichen-like dark dorsal patches

from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz

Alternate Names
Formerly Rana muscosa - Mountain Yellow-legged Frog (which included the species Rana sierrae.)
Rana muscosa - Sierra Madre Yellow-legged Frog

Related or Similar California Frogs
Rana aurora
Rana boylii
Rana cascadae
Lithobates catesbeiana
Rana draytonii
Lithobates pipiens
Rana pretiosa
Rana sierrae
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.

Lang Elliott, Carl Gerhardt, and Carlos Davidson - The Frogs and Toads of North America - Houghton Mifflin Harcourt. 2009.

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 and the Endangered and Threatened Animals List which are published by the California Department of Fish and Wildlife.


 


Organization
Status Listing
U.S. Endangered Species Act (ESA) See Below
California Endangered Species Act (CESA) SE - 4/1/13 Endangered
California Department of Fish and Wildlife DFG:SE Endangered
Bureau of Land Management None
USDA Forest Service USFS:S Sensitive
The ESA lists Rana muscosa in two separate regions using the common name Mountain yellow-legged frog.

  State Listing Federal Listing
Southern California DPS
(San Gabriel, San Jacinto, and San Bernardino Mountains only.)
(SE) Endangered FE - 8/01/02 Endangered
Northern California DPS
 (North of the Tehachapi Mountains from the Monarch Divide to portions of the Kern River drainage.)
(SE) Endangered FPE - 4/25/13 Federally Proposed (Endangered)
 

Home Site Map About Us Identification Lists Maps Photos More Lists CA Snakes CA Lizards CA Turtles CA Salamanders CA Frogs
Contact Us Usage Resources Rattlesnakes Sounds Videos FieldHerping Yard Herps Behavior Herp Fun CA Regulations
Beyond CA All Herps


Return to the Top

 © 2000 -