Archived Workshops/References

California Red Legged Frog


The California red-legged frog has been protected as a threatened species by the Endangered Species Act since June 1996. The California red-legged frog is the largest native frog in the western United States. It is one of two subspecies of the red-legged frog found on the Pacific coast; the other is the northern red-legged frog Rana aurora aurora. The California red-legged frog once ranged across much of California, including portions of the Sierra Nevada Mountain Range, where it is believed to be the title character of Mark Twain's famed short story, "The Celebrated Jumping Frog of Calaveras County." In 1865, when the story was written, red-legged frogs were the largest frogs in the state; bullfrogs were not introduced to California until 1896. California red-legged frogs have been eliminated from more than 70 percent of their historic habitat. Surveys indicate the frogs are present in about 10 percent of their historic locations. California red-legged frogs are found primarily in wetlands and streams in coastal drainages of central California. Today they are known to occur in about 238 streams or drainages in 23 counties. Monterey, San Luis Obispo, and Santa Barbara counties support the greatest amount of currently occupied habitat. Only four areas within the entire historic range of the subspecies may currently support more than 350 adults. The above is quoted from the USFWS website.

Training Programs

California Red-Legged Frog Field Praticum #1 for repeat Workshop
California Red-Legged Frog Workshop Field Session #1 Mar 14, 2007
California Red-Legged Frog Workshop Mar 15, 2007
California Red-Legged Frog Workshop Field Session #2 Mar 15, 2007 - Mar 16, 2007
California Red-Legged Frog Repeat Workshop: Field Session #1 Mar 21, 2007
California Red-Legged Frog Repeat Workshop: Field Session #2 Mar 22, 2007
California Red-Legged Frog Workshop - Repeat Mar 22, 2007
California Red-Legged Frog Field Training Session #2 Apr 15, 2008
California Red-Legged Frog Workshop Apr 15, 2008
California Red-Legged Frog Field Training Night #2 Mar 26, 2009
California Red-Legged Frog Workshop 2009 Mar 26, 2009
California Red-Legged Frog Workshop Field Practicum #1 2010 Apr 7, 2010
California Red-Legged Frog Workshop 2010 Apr 8, 2010
California Red-Legged Frog Workshop Field Practicum #2 2010 Apr 8, 2010
California Red-Legged Frog Field Practicum #1 2011 Apr 13, 2011
California Red-Legged Frog Field Practicum #2 2011 Apr 14, 2011
California Red-Legged Frog Workshop 2011 Apr 14, 2011
California Red-legged Frog Field Practicum #1a 2011 Apr 27, 2011
California Red-legged Frog Field Practicum #2a 2011 Apr 28, 2011
California Red-legged Frog repeat workshop 2011 Apr 28, 2011
California Red-Legged Frog Management Factors May 19, 2011
California Red-Legged Frog Field Practicum #1 2012 Apr 11, 2012
California Red-Legged Frog Field Practicum #2 2012 Apr 12, 2012
California Red-legged Frog Workshop 2012 Apr 12, 2012
California Red-Legged Frog Field Practicum #1 for repeat Workshop 2012 Apr 25, 2012
California Red-Legged Frog Field Practicum #2 for repeat Workshop 2012 Apr 26, 2012
California Red-legged Frog Repeat Workshop 2012 Apr 26, 2012
California Red-Legged Frog Field Practicum #1 2013 May 8, 2013
California Red-Legged Frog Field Practicum #2 2013 May 9, 2013
California Red-Legged Frog Workshop 2013 May 9, 2013
California Red-Legged Frog Repeat Field Practicum #1 2013 May 15, 2013
California Red-Legged Frog Repeat Field Practicum #2 2013 May 16, 2013
California Red-legged Frog Repeat Workshop 2013 May 16, 2013
Managing Habitats for California Red-legged Frog Workshop 2013 Nov 7, 2013
California Red-Legged Frog Field Practicum #1 2014 May 14, 2014
California Red-Legged Frog Field Practicum #2 2014 May 15, 2014
California Red-Legged Frog Workshop 2014 May 15, 2014
Managing Habitats for the California Red-legged Frog Workshop 2014 Oct 2, 2014
California Red-legged Frog Workshop 2015 Field Practicum #1 May 20, 2015
California Red-Legged Frog Workshop 2015 May 21, 2015
California Red-legged Frog Workshop 2015 Field Practicum #2 May 21, 2015
Managing Habitats for the California Red-legged Frog 2015 Oct 22, 2015
Ecology of the California Red-legged Frog- Night Time Field Training Session #1 May 4, 2016
Ecology of the California Red-legged Frog May 5, 2016
Ecology of the California Red-legged Frog- Night Time Field Training Session #2 May 5, 2016
Ecology of the California's Red-legged Frog - for CDFW May 12, 2016
Managing Habitats for the California Red-legged Frog Oct 6, 2016

Documents and Publications

Handouts: California Red-legged Frog Workshop
PDF, 364KB
Apr 30 13
Trish Tatarian and Greg Tatarian
Elkhorn Slough Coastal Training Program
Handouts for the CRF workshop
Presentation: Ecology of the California Red-legged Frog
PDF, 3.8MB
Aug 19 14
Trish Tatarian and Greg Tatarian
Elkhorn Slough Coastal Training Program
Workshop presentation
Selected and annotated bibliography of the California red-legged frog (Rana draytonii)
DOC, 115KB
Apr 30 13
Trish Tatarian and Greg Tatarian
Elkhorn Slough Coastal Training Program
February 2015
CRLF 2015 Bibliography
A Monograph of the American Frogs of the Genus Rana
PDF, 5.5MB
May 23 14
G. A. Boulenger
Cf. Bull. Soc. Zool. France, 111
A Technique for Locating and Recovering Radiotransmitters at Close Range
Mar 02 07
Gary M. Fellers Patrick Kleeman
Herpetological Review, 2003, 34(2), 123
Activities of four frog skin-derived antimicrobial peptides (temporin-1DRa, temporin-1Va and the melittin-related peptides AR-23 and RV-23) against anaerobic bacteria
May 27 14
Edit Urban, Elisabeth Nagy, Tibor Pal, Agnes Sonnevend, J. Michael Conlon
International Journal of Antimicrobial Agents, 29:317-321
The activities of two antimicrobial peptides belonging to the temporin family (temporin-1DRa from Rana draytonii and temporin-1Va from Rana virgatipes) and two peptides with structural similarity to the bee venom peptide melittin (AR-23 from Rana tagoi and RV-23 from R. draytonii) were evaluated against a range of reference strains and clinical isolates of anaerobic bacteria.
Amphibian chytrid fungus (Batrachochytrium Dendrobatidis) in coastal and montane California, USA Anurans
PDF, 574KB
May 23 14
Gary M. Fellers, Rebecca A. Cole, David M. Reinitz, and Patrick M. Kleeman
Herpetological Conservation and Biology 6(3):383–394
We found amphibian chytrid fungus (Bd = Batrachochytrium dendrobatidis) to be widespread within a coastal watershed at Point Reyes National Seashore, California and within two high elevation watersheds at Yosemite National Park, California.
Biochemical identification of red-legged frogs, Rana aurora draytonii (Ranidae) at Duckwater, Nevada
PDF, 374KB
May 23 14
D. Green
The Southwestern Naturalist, 30(4):614-616
A substantial population of frogs exists at the isolated, warm water springs of Duckwater, a Shoshone Indian reservationin the Railroad Valley of Nye Co., Nevada
Biochemical, behavioral, and body size differences between Rana aurora aurora and R. a. draytoni
PDF, 669KB
May 23 14
M.P. Hayes and M. M. Miyamoto
Copeia, 4:1018-1022
We describe significant electrophoretic, behavioral and body size dif- ferences between representative populations of R. a. aurora and R. a. draytoni. Our original biochemical, ethological and morphological data are coupled with published observations. Using these data, we question further the current taxonomic designation of the two taxa.
Bullfrogs, disturbance regimes, and the persistence of California red-legged frogs
PDF, 2.7MB
May 23 14
Rebecca A. Doubledee, Erik B. Muller, Roger M. Nisbet
Journal of Wildlife Management, 67(2):424-438
Our model, plus experimental studies that link specific environmental factors to the bullfrog predation rate, can provide managers with a useful tool for controlling populations and facilitating conservation efforts for the California red-legged frog.
California Red-Legged Frog (Rana draytonii) Movement and Habitat Use: Implications for Conservation
May 23 14
Gary M. Fellers and Patrick M. Kleeman
Journal of Herpetology, Vol. 41, No. 2, 276-286
Our data demonstrate that maintaining populations of pond-breeding amphibians requires that all essential habitat components be protected; these include (1)breeding habitat, (2)nonbreeding habitat, and (3)migration corridors. In addition, a buffer is needed aroundall three areas to ensure that outside activities do not degrade any of the three habitat components.
Cattle Grazing Mediates Climate Change Impacts in Ephemeral Wetlands
PDF, 186KB
May 14 13
Christopher Pyke and Jaymee Marty
Conservation Biology, 19(5):1619-1625
Data from a grazing exclosure study indicated that 3 years after the removal of grazing, ungrazed vernal pools dried an average of 50 days per year earlier than grazed control pools. Modeling showed that regional climate change could also alter vernal pool hydrology. Increased temperatures and winter precipitation were predicted to increase periods of inundation.
Characteristics of some new Reptiles in the Museum of the Smithsonian Institution
PDF, 2.2MB
May 23 14
Spencer F. Baird and Charles Girard
Proceedings of the Academy of Natural Sciences of Philadelphia, 6
Community ecology of invasions: direct and indirect effects of multiple invasive species on aquatic communities
PDF, 5.4MB
May 01 14
Daniel L. Preston, Jeremy S. Henderson, and Pieter T. J. Johnson
Ecology, 93(6):1254-1261
Our results highlight how the net effects of multiple nonnative species depend on the trophic level of each invader, the form and magnitude of invader interactions, and the traits of native community members.
Decline of Ranid Frog Species in Western North America: Are Bullfrogs (Rana catesbeiana) Responsible?
PDF, 542KB
May 23 14
Marc P. Hayes and Mark R. Jennings
Journal of Herpetology, Vol. 20, No. 4, 490-509
Declines of the California red-legged frog: climate, UV-B, habitat, and pesticides hypothesis
PDF, 201KB
May 23 14
Carlos Davidson, H. Bradley Shaffer, and Mark R. Jennings
Ecological Applications, 11(2):464-479
The federally threatened California red-legged frog (Rana aurora draytonii) has disappeared from much of its range for unknown reasons. We mapped 237 historic locations for the species and determined their current population status.
Declining downwind: amphibian population declines in California and historical pesticide use
PDF, 196KB
May 23 14
Carlos Davidson
Ecological Applications, 14(6):1892-1902
My study examines the association between the spatial patterns of declines for five California amphibian species and historical patterns of pesticide use in California from 1974 to 1991 based on Department of Pesticide Regulation records.
Diurnal Versus Nocturnal Surveys for California Red-Legged Frogs
PDF, 1.3MB
May 23 14
Gary M. Fellers and Patrick M. Kleeman
Journal of Wildlife Management, 70(6):1805-1808
We conducted paired diurnal and nocturnal surveys for adult and subadult California red-legged frogs at sites in the California Coast Range and SierraNevada foothills.
Do a threatened native amphibian and its invasive congener differ in response to human alteration of the landscape?
PDF, 199KB
Apr 01 09
Antonia D'Amore, Valentine Hemingway, Kerstin Wasson
Biological Invasions, 12(1):145-154
Anthropogenic changes to habitat are a global phenomenon and the impact of these changes may act in tandem to cause loss of biodiversity. One major global change is the introduction of invasive species. In order to determine whether other human impacts might correlate with populations of invaders, we examined the habitat correlates of distribution, persistence and reproduction of a global invader, the American bullfrog (Rana catesbeiana). We then compared these correlates with those of a threatened, native congener, the California red-legged frog (Rana draytonii). We found striking differences between the two species in response to habitat fragmentation and degradation. Our work suggests that human alteration of habitat, in particular the hydrology of freshwater sites and through building roads, favors this invasive species across the landscape.
Effects of Introduced Bullfrogs, Rana catesbeiana, on the Native Frogs of the San Joaquin Valley, California
PDF, 152KB
May 23 14
Peter B. Moyle
COPEIA, 1:18-22
The disappearance of R. aurora from the region, and the con- tinuing reduction in range of R. boylii, is attributed to habitat alteration coupled with predation and competition from R. catesbeiana.
Effects of Introduced Mosquitofish and Bullfrogs on the Threatened California Red-Legged Frog
PDF, 2.1MB
May 23 14
Sharon P. Lawler, Deborah Dritz, Terry Strange and Marcel Holyoak
Conservation Biology, Vol 13, No. 3, 613-622
Exotic species have frequently caused declines of native fauna and may contribute to some cases of amphibian decline. Introductions of mosquitofish (Gambusia affinis) and bullfrogs (Rana catesbeiana) are suspected to have caused the decline of California red-leggedfrogs (Rana aurora draytonii).
Effects of the herbicide imazapyr on juvenile Oregon spotted frogs
PDF, 218KB
May 24 13
Amy E. Yahnke, Christian E. Grue, Marc P. Hayes, and Alexandra T. Troian
Environmental Toxicology and Chemistry, Vol. 32, No. 1, pp. 228-235
The results suggest that imazapyr use in wetland restoration poses a low risk of direct toxic effects on juvenile OSFs.
Epizootiology of Sixty-Four‘‡’ Amphibian Morbidity and Mortality Events in the USA, 1996-2001
PDF, 737KB
May 23 14
D. Earl Green, Kathryn A. Converse, and Audra K. Schrader
Annals of the New York Academy of Sciences, 969: 323-339
A total of 44 amphibian mortality events and 20 morbidity events were reviewed retrospectively.
Evaluation of a radio-belt for ranid frogs
PDF, 136KB
Mar 21 09
Galen Rathbun and Thomas Murphey
Herpetological Review 27(4):187-189
Describes a new method of attaching radios to ranid frogs.
Evidence from peptidomic analysis of skin secretions that the red-legged frogs, Rana aurora draytonii and Rana aurora aurora, are distinct species
PDF, 446KB
May 23 14
J. Michael Conlon, Nadia Al-Ghafaria, Laurent Coquetb, Jerome Leprince, Thierry Jouenne, Hubert Vaudry, Carlos Davidson
Peptides, 27:1305-1312
The data emphasize that amino acid sequences of antimicrobial peptides in skin secretions may be used to infer taxonomic and phylogenetic relationships between species of ranid frogs.
Farm practices for food safety: an emerging threat to floodplain and riparian ecosystems
PDF, 456KB
Apr 22 14
Sasha Gennet, Jeannette Howard, Jeff Langholz, Kathryn Andrews, Mark D. Reynolds, and Scott A. Morrison
Frontiers in Ecology and the Environment
History and status of the California red-legged frog in the Sierra Nevada, California, USA
PDF, 2.3MB
May 01 14
Sean J. Barry and Gary M. Fellers
Herpetological Conservation and Biology, 8(2):456-502
Evaluation of the status of the CRLF in the sierra nevada.
Importance of Native Amphibians in the Diet and Distribution of the Aquatic Gartersnake (Thamnophis atratus) in the San Francisco Bay Area of California
PDF, 452KB
May 01 14
D. Preston and P. Johnson
Journal of Herpetology, 46(2):221-227
Analysis of stomach contents indicated that Pacific Chorus Frogs (Pseudacris regilla) were the most important amphibian prey, followed by Western Toads (Anaxyrus [=Bufo]boreas), California Newts (Taricha torosa), and California Red-legged Frogs (Rana draytonii). The occurrence of T. atratus at a pond associated positively with the presence of all native amphibian species but negatively associated with the presence of introduced American Bullfrogs (Lithobates catesbeianus [=Rana catesbeiana]).
Invasive species shifts onto genetic resource partitioning and microhabitat use of a threatened native amphibian
PDF, 164KB
Apr 05 10
Antonia Amore, Eric Kirby, Michael McNicholas
Aquatic Conservation: Marine and Freshwater Ecosystems 19: 534-541
3. There was a marked increase in the total number of adult California red-legged frogs seen in all of the ponds after the first year of bullfrog removal, suggesting that these adults were in the ponds, but hiding when invaders were present. Ontogenetic partitioning of habitat in this species was documented, as well as a shift in that partitioning and increased hiding behaviour with adult bullfrog presence.
Landscape epidemiology of Batrachochytrium dendrobatidis in central California
PDF, 466KB
May 27 14
Gretchen E. Padgett-Flohr and Robert L. Hopkins, II
Ecography 33:688-697
In this study, we analyzed how environmental factors, land use practices, and landscape structure may affect the dynamics of the pathogen’s distribution in a landscape dominated by lentic systems within a region of Mediterranean climate.
Microhabitat use of the California Red-legged frog and introduced bullfrog in a seasonal marsh
PDF, 551KB
May 23 14
David G. Cook and Mark R. Jennings
Herpetologica 63(4):430-440
We quantified frog phenology and microhabitat use of the native California red-legged frog (Rana draytonii) and introduced bullfrog (Rana catesbeiana) in an 11-ha seasonal marsh, Sonoma County, California. Logistic regression showed that both species selected habitats nonrandomly from among the available habitats in the marsh.
Molecular and Ecological Characterization of Extralimital Populations of Red-Legged Frogs from Western North America
PDF, 2.6MB
May 28 14
Gregory B. Pauly, Santiago R. Ron, and Lance Lerum
Journal of Herpetology, Vol. 42, No. 4, 668-679
We compare new mtDNA sequence data from these extralimital populations to available sequences from 50 populations from the core range of red-legged frogs
Movement patterns of California red-legged frogs in an inland California environment
PDF, 748KB
Jan 29 13
Patricia J. Tatarian
Herpetological Conservation and Biology 3(2):155-169
March 30, 2008
Peer reviewed paper on CRLF movement patterns in inland California.
Overwintering tadpoles in the California red-legged frog (Rana aurora draytonii)
Mar 02 07
Gary M. Fellers, Alan E. Launer, Galen Rathbun, Steve Bobzien, Jeff Alvarez, David Sterner, Richard B. Seymour, and Michael Westphal,
Herpetological Review, 32(3), 156-157
Pathogenicity of Batrachochytrium Dendrobatidis in Two Threatened California Amphibians: Rana draytonii and Ambystoma californiense
PDF, 367KB
May 27 14
Gretchen E. Padgett-Flohr
Herpetological Conservation and Biology 3(2):182-191
Peptide defenses of the Cascades frog Rana cascadae: implications for the evolutionary history of frogs of the Amerana species group
PDF, 467KB
May 23 14
J. Michael Conlon,, Ahmed al-Dhaheri, Eissa al-Mutawa, Rokaya al-Kharrge, Eman Ahmed, Jolanta Kolodziejek, Norbert Nowotny, Per F. Nielsen, Carlos Davidson
Peptides 28:1268-1274
Population declines lead to replicate patterns of internal range structure at the tips of the distribution of the California red-legged frog
PDF, 1.8MB
May 01 14
Jonathan Q. Richmond, Adam R. Backlin, Patricia J. Tatarian, Ben G. Solvesky, and Robert N. Fisher
Biological Conservation 172:128-137
We show that ‘external’ Sierra Nevada populations have lower genetic diversity and are more differentiated from one another than their ‘internal’ Bay Area counterparts.
Population genetics of the frog-killing fungus Batrachochytrium dendrobatidis
PDF, 1.4MB
May 27 14
Jess A. T. Morgan, Vance T. Vredenburg, Lara J. Rachowicz, Roland A. Knapp, Mary J. Stice, Tate Tunstall, Rob E. Bingham, John M. Parker, Joyce E. Longcore, Craig Moritz, Cheryl J. Briggs, and John W. Taylor
Pnas Vol. 104, No. 34, 13845-13850
Pre-1900 overharvest of California red-legged frog (Rana aurora draytonii): The inducement for bullfrog (Rana catesbeiana) introduction
PDF, 326KB
May 27 14
Mark R. Jennings and Marc P. Hayes
Herpetologica 41(3):94-103
Pre-1900 frog harvest data from California suggests heavy exploitation of California red-legged frogs (Rana aurora draytonii). A comparison with data collected from present-day, non-exploited, healthy populations of R. a. draytonii suggest that mostly female frogs may have been harvested.
Rana draytonii dispersal
Jun 14 11
Mark Allaback, David M. Laabs, David S. Keegan, Josh D. Harwayne
Herpetological Review, 41 (2), 204-206
Rana draytonii (California red-legged frog). Behavior- dangers of drift fences
Mar 21 09
Galen Rathbun, Norman Scott, Thomas Murphey
Herpetological Review 28(2):85-86
A research note with information about California red-legged frog behavior. This particularly deals with the danger of drift fence barriers to the species.
Rana Draytonii (California Red-legged Frog). Egg Predation.
Mar 21 09
Galen Rathbun
Herpetological Review 29(3):165
This is a research note that describes important factors of egg predation to the California red-legged frog.
Rana draytonii (California Red-Legged Frog). Predation.
PDF, 216KB
Jun 04 12
Jeff Wilcox
Herpetological Review 42(3):414-415
Bullfrogs found with red-legged young in their stomachs.
Rana Draytonii (California Red-legged Frog). Prey.
Mar 20 09
Marc P. Hayes, Mark R. Jennings, Galen B. Rathbun
Herpetological Review 37(4):449
A note explaining prey of California red-legged frog.
Relocations of California red-legged frogs, California, USA.
PDF, 1.2MB
May 25 11
Dana Bland
Re-introduction News, Newsletter of the Re-introduction Specialist Group, IUCN, No. 25:12-13.
Reproductive Interference by an Invasive Species an Evolutionary Trap?
PDF, 130KB
Apr 05 10
Antonia D'Amore, Eric Kirby, Valentine Hemingway
Herpetological Conservation and Biology 4(3):325-330
We detected 43 cases of interspecific amplexus over three years between a threatened amphibian, Rana draytonii, and its invasive competitor and predator, Rana catesbeiana.
Spatial Tests of the Pesticide Drift, Habitat Destruction, UV-B, and Climate-Change Hypotheses for California Amphibian Declines
PDF, 3.8MB
May 23 14
Carlos Davidson, H. Bradley Shaffer, and Mark R. Jennings
Conservation Biology, 16(6):1588-1601
Using a geographic information system, we constructed maps of the spatial pattern of declines for eight declining California amphibian taxa, and compared the observed patterns of decline to those predicted by hypotheses of wind-borne pesticides, habitat destruction, ultraviolet radiation, and climate change.
Species boundaries, phylogeography and conservation genetics of the red-legged frog (Rana aurora/draytonii) complex
PDF, 379KB
May 23 14
H. Bradley Shaffer, G. M. Fellers, S. Randal Voss, J. C. Oliver, and Gregory B. Pauly
Molecular Ecology
The currently available evidence favours recognition of aurora and draytonii as separate species with a narrow zone of overlap in northern California.
Sympatry in California tiger salamander and Californa red-legged frog breeding habitat within their overlapping range
PDF, 145KB
May 01 14
Jeff A. Alvarez, Mary A. Shea, Jeffery T. Wilcox, Mark L.. Allaback, Sarah M. Foster, Gretchen E. Padgett-Flohr, and Jennifer L. Haire
California Fish and Game 99(1):42-48
Accounts of sympatry in the breeding habitat of two protected amphibians that have not been reported elsewhere that may affect management of both species.
Terrestrial activity and conservation of adult California red-legged frogs Rana aurora draytonii in coastal forests and grasslands
PDF, 349KB
Mar 20 09
John B. Bulger, Norman J. Scott Jr., Richard B. Seymour
Biological Conservation 110:85-95
The federally threatened California red-legged frog Rana aurora draytonii occupies both aquatic and terrestrial habitats in its adult life stage. The terrestrial activities of this species are not well known and require documentation to assist in the development of appropriate levels of protection under the US Endangered Species Act. We studied the terrestrial activities of radio-tagged red legged frogs (n=8-26) inhabiting a coastal watershed in Santa Cruz County, California, during 1997-1998. In particular, we investigated (1) the use of terrestrial habitats by non-migrating adults in relation to season, breeding chronology, and precipitation, and (2) adult migration behavior, including seasonal timing, duration, distances traveled, and the use of corridors. (more)
The Decline of Amphibians in California's Great Central Valley
PDF, 1.8MB
May 23 14
Robert N. Fisher and H. Bradley Shaffer
Conservation Biology 10(5):1387-1397
Declines in amphibian populations are rarely reported on the community or ecosystem level. We combined broad-scale field sampling with historical analyses of museum records to quantify amphibian declines in California's Great Central Valley
Translocation of California red-legged frogs (Rana aurora draytonii)
PDF, 789KB
Mar 21 09
Galen Rathbun and Julie Schneider
Wildlife Society Bulletin 29(4):1300-1305
Offers information about the risk of moving individual frogs and suggests considerations for doing so.
Variation in Pesticide Tolerance of Tadpoles among and within Species of Ranidae and Patterns of Amphibian Decline
PDF, 1.2MB
May 23 14
Christine M. Bridges and Raymond D. Semlitsch
Conservation Biology 14(5):1490-1499
Chemical contamination, at lethal or sublethal level, can alter natural regulatory processes such as juvenile recruitment in amphibian populations and should be considered a contributing cause of declines in amphibian populations.
Vocal Sac Variation among Frogs of the Genus Rana from Western North America
PDF, 1.6MB
May 23 14
Marc P. Hayes and Dana M. Krempels
Copeia 4:927-936
Vocal sac condition of 460 frogs was examined by dissection for five western North American Rana (Rana boylii group sensu Case, 1978): R. aurora (N = 280), R. boylii (N = 24), R. cascadae (N = 113), R. muscosa (N = 22) and R. pretiosa (N = 21).
Water Temperatures in a California Red-legged breeding pond
PDF, 624KB
Apr 12 13
Galen Rathbun
Immediate Science Ecology 1: 7-11
September 5, 2012
This report describes the use of data loggers to gather water temperature profiles, which demonstrates the potential for broader research on the topic. In addition, the preliminary results and discussion will assist resource managers to better understand and develop optimal management and restoration activities for the threatened frog.
A Standardized Protocol for Surveying Aquatic Amphibians
PDF, 410KB
Mar 02 07
Gary M. Fellers Kathleen L. Freel
National Park Service
May 1995
Amphibian and Reptile Species of Special Concern in California
PDF, 5.3MB
May 27 14
Mark R. Jennings and Marc P. Hayes
Final Report for California Department of Fish and Game
The California Department of Fish and Game commissioned this study as part of the Inland Fisheries Division Endangered Species Project.
Amphibians and Reptiles in Nevada
PDF, 8.7MB
May 23 14
Jean M. Linsdale

Breeding Pond Dispersal of Interacting California Red-Legged Frogs (Rana draytonii) and American Bullfrogs (Lithobates catesbeianus) of California: A Mathematical Model of Management Strategies
PDF, 6.3MB
May 23 14
Iris Acacia Gray
A Thesis Presented to The Faculty of Humboldt State University
CRLF Survey Appendix D - Site Assessment
Jan 26 11
US Fish and Wildlife Service
US Fish and Wildlife Service
Endangered and Threatened Wildlife and Plants; Determination of Threatened Status for the California Red-Legged Frog
PDF, 154KB
Mar 02 07
US Fish and Wildlife Service
USFWS Federal Register, Vol. 61, No. 101, 25813-25833
May 23, 1996
Frog & Toad Calls of the Pacific Coast
May 23 14
Carlos Davidson

Habitat characteristics of California red-legged frog (Rana draytonii): ecological differences between eggs, tadpoles, and adults in a coastal brackish and freshwater system
PDF, 2.4MB
May 25 11
Dawn Kathleen Reis
A Thesis Presented to San Jose State University
December 1999
Light Source and Binoculars for Visual Encounter Surveys of Adult California Red-legged Frogs
Sep 21 12
Trish Tatarian Greg Tatarian Norman Scott

September 2012
Paper on selecting lights and binoculars for conducting California Red-legged Frog surveys.
Management Guidlines for the California Red-Legged Frog
PDF, 188KB
Mar 20 09
Drs. Galen Rathbun and Norman Scott
Elkhorn Slough Coastal Training Program
February 2009
This technical paper provides a bibliography and management guidelines for the California red-legged frog. Information presented is not peer-reviewed but is the experience of the authors, who have extensive experience with the organism. Please contact us if you have any concerns or suggestions about the information presented.
Microhabitat use and reproductive success of the California Red-legged frog (Rana aurora draytonii) and bullfrog (Rana catesbeiana) in an ephemeral marsh
PDF, 6.6MB
May 23 14
David Cook
Sonoma State University thesis
I undertook a study of the habitat use, distribution. and factors influencing the reproductive success of the threatened California red-legged frog (Rana aurora draytonU) and introduced bullfrog (Rana catesbeiana) at Ledson Marsh, Sonoma County, California.
Problems and opportunities managing invasive bullfrogs: is there any hope?
PDF, 204KB
May 09 12
Adams, M. J. and C. A. Pearl
Biological invaders in inland waters: Profiles, distribution, and threats. F. Gherardi, editor. Springer Publication Company, New York. 734 pp.
"...consider the case of the Bullfrog, review management options, and suggest directions for future research with this and similar species."
Reports of the decline of Mark Twain's
PDF, 4.3MB
Jun 24 14
Robert L. Bugg
Sustainable Agriculture: The Newsletter of the University of California Sustainable Agriculture Research and Education Program, Vol. 19, No. 1
Response of California Red-legged Frogs to Removal of Non-Native Fish
May 23 14
Jeff A. Alvarez, Carissa Dunn, Andrea F. Zuur
Transactions of the Western Section of the Wildlife Society, 9-12
Revised Guidence on Site Assessments for California Red Legged Frog
PDF, 143KB
Jan 26 11
US Fish and Wildlife
US Fish and Wildlife
August 2005
Status of the California red-legged frog and California tiger salamander at Concord Naval Weapons Station, California
PDF, 633KB
May 27 14
Eric W. Stitt and Giselle T. Downard
Transactions of the Western Section of The Wildlife Society 36:32-39
The sustained presence of California red-legged fiogs and California tiger salamanders at CNWS is likely due to a combination of factors including absence of aquatic predators, low occurrence of migration barriers, presence of upland refugia, connectivity between water resources, and low levels of human disturbance relative to urban areas that border CNWS.
Stockpond management for the benefit of California red-legged frog
PDF, 101KB
May 24 13
Norman Scott Galen Rathbun Trish Tatarian

Pond management recommendations for Red-legged Frogs
The Amphibian Tree of Life
PDF, 9.2MB
May 23 14
Darrel R. Frost, Taran Grant, Julian Faivovich, Raoul H. Bain, Alexander Haas, Celio F.B. Haddad, Rafael O. De Sa, Alan Channing, Mark Wilkinson, Stephen C. Donnellan, Christopher J. Raxworthy, Johnathan A. Campbell, Boris L. Blotto, Paul Moler, Robert C. Drewes, Ronald A. Nussbaum, John D. Lynch, David M. Green, and Ward C. Wheeler
Bulletin of the American Museum of Natural History No. 297


USFWS: Revised Guidance on Site Assessments and Field Surveys for the California Red-legged Frog
Apr 01 09
California red-legged frog sounds, pictures, and information
Apr 24 08
Recovery Plan for the California Red-legged Frog (Rana draytonii)
Apr 16 12
Center for North American Herpetology - California Herp Checklist
Jan 25 13
Solano County CRLF Translocation Project
May 14 13
EPA- Pesticide Effects Determinations for the California Red-legged Frog and other California Listed Species
May 24 13
Settlement will Safeguard Endangered California Frog from Pesticides
Nov 12 13