Rana cascadae - Slater, 1939
Cascades Frog
Other English Common Names: Cascades frog
Taxonomic Status: Accepted
Related ITIS Name(s): Rana cascadae Slater, 1939 (TSN 173450)
Unique Identifier: ELEMENT_GLOBAL.2.103017
Element Code: AAABH01060
Informal Taxonomy: Animals, Vertebrates - Amphibians - Frogs and Toads
Kingdom Phylum Class Order Family Genus
Animalia Craniata Amphibia Anura Ranidae Rana
Genus Size: D - Medium to large genus (21+ species)
Check this box to expand all report sections:
Concept Reference
Concept Reference: Frost, D. R. 1985. Amphibian species of the world. A taxonomic and geographical reference. Allen Press, Inc., and The Association of Systematics Collections, Lawrence, Kansas. v + 732 pp.
Concept Reference Code: B85FRO01HQUS
Name Used in Concept Reference: Rana cascadae
Taxonomic Comments: MtDNA data suggest that R. aurora, R. cascadae, and R. muscosa form a clade within the R. boylii species group (Macey et al. 2001).
Conservation Status

NatureServe Status

Global Status: G3G4
Global Status Last Reviewed: 22Dec2010
Global Status Last Changed: 15Nov2001
Rounded Global Status: G3 - Vulnerable
Reasons: Moderately small range in mountains from Washington to northern California; many extant populations; common in some areas but has declined in other areas, particularly at the edges of the range; impacts of airborne agrochemicals may be contributing to the decline.
Nation: United States
National Status: N3N4 (15Nov2001)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States California (S3), Oregon (S3S4), Washington (S3S4)

Other Statuses

IUCN Red List Category: NT - Near threatened

NatureServe Global Conservation Status Factors

Range Extent: 20,000-200,000 square km (about 8000-80,000 square miles)
Range Extent Comments: Range extends from the Cascade and Olympic mountains of northern Washington south to northern California. Populations in the Olympic Mountains of Washington and the Trinity Alps, Mt. Shasta, and Mt. Lassen areas of California are notably disjunct from the primary distribution along the main Cascade axis (Pearl and Adams 2005). Historical locations at low elevations in Washington suggest that the species formerly may have been more broadly distributed (Leonard et al. 1993). Historical elevational range extended from around 400 to 2,500 meters.

Area of Occupancy:  
Area of Occupancy Comments: This species often is absent from what appears to be suitable habitat (Leonard et al. 1993).

Number of Occurrences: 81 - 300
Number of Occurrences Comments: This species is represented by a large number of occurrences (subpopulations. Hundreds of unique locations are known in Washington, but some of these are likely no longer extant, and others should be combined into single occurrences (Dvornich et al. 1997). Oregon has approximately 70 occurrences. Few occurrences remain in California (Fellers and Drost 1993), where Altig and Dumas (1971) mapped 12 collection sites.

Population Size: 10,000 - 1,000,000 individuals
Population Size Comments: This species is abundant in many parts of its range (Leonard et al. 1993). For example, in mountain meadows in Oregon, numbers were estimated to be hundreds within an area of less than 1 hectare (Nussbaum et al. 1983).

Number of Occurrences with Good Viability/Integrity: Many (41-125)
Viability/Integrity Comments: Many occurrences appear to have at least good viability.

Overall Threat Impact: Medium
Overall Threat Impact Comments: Causes of declines are not fully known, but introduced trout, UV-B radiation, fungal pathogens, and loss of open meadow habitat due to fire suppression have been suggested (Hayes and Jennings 1986, Fellers and Drost 1993, Blaustein et al. 1994, Kiesecker and Blaustein 1995, Fite et al. 1998, Adams et al. 2001).

Declines in Lassen Volcanic National Park apparently are due to a combination of local factors, including (1) presence of non-native predatory fishes that have restricted available habitat and limited dispersal of frogs, (2) gradual loss of open meadows and associated aquatic habitats, and (3) loss of breeding habitat due to drought (Fellers and Drost 1993). In this region, fire suppression and cessation of cattle grazing have increased the natural invasion of shrubs and trees into open meadows; former open breeding sites are now clogged with vegetation (Fellers and Drost 1993).

Decline may be related to sensitivity of eggs to increased levels of ultraviolet radiation resulting from ozone depletion (Blaustein et al. 1994), but spectral characteristics of natural waters likely shield eggs from detrimental physiological effects in all but the clearest waters (Palen et al. 2002). Increased solar radiation also may be damaging frog retinas (Fite et al. 1998).

Eggs are highly susceptible to the pathogenic fungus Saprolegnia ferax, which may be introduced during fish stocking (Kiesecker and Blaustein 1997).

Cascades frogs seem to be sensitive to habitat fragmentation. Dispersal is limited by moisture-temperature conditions (Blaustein et al. 1995). However, adults regularly range onto mountain slopes far from aquatic or wetland habitats when conditions are suitably moist (G. Hammerson, pers. obs.). and may have better dispersal ability than currently documented. For example, R. cascadae was among the first amphibians to recolonize sites after the eruption of Mount St. Helens in the southern Washington Cascades and now is common there (Karlstrom 1986; Crisafulli and Hawkins 1998; C. Crisafulli, personal communication, cited by Pearl and Adam 2005).

Agrochemicals may be a threat in some areas. Davidson et al. (2002) found support for the hypothesis that airborne agrochemicals have contributed to the decline. Fertilizers such as urea may pose a threat; in laboratory studies, juveniles were unable to sense and avoid toxic levels (Hatch et al. 2001). Nitrites may affect behavior and metamorphosis of larvae (Marco and Blaustein 1999).

An Oregon study failed to detect short-term changes in breeding phenology that might be attributable to climate change (Blaustein et al. 2001).

Short-term Trend: Decline of <30% to relatively stable
Short-term Trend Comments: Trend over the past 10 years or three generations is uncertain, but area of occupancy, population size, number of occurrences, and habitat quality probably are slowly declining or relatively stable in the large majority of the range.

Long-term Trend: Decline of 30-50%
Long-term Trend Comments: Surveys in the mid- to late 1990s in Olympic and Mount Ranier national parks, Washington, found no evidence of a decline (Adams et al. 2001, Tyler et al. 2002), and the species rebounded after the eruption of Mount St. Helens (Karlstrom 1986; Crisafulli and Hawkins 1998; C. Crisafulli, personal communication, cited by Pearl and Adam 2005).

Declines in Oregon were cited by Nussbaum et al. (1983) and Blaustein and Wake (1990), but other data do not suggest exceptionally low site occupancy rates (Brown 1997, unpublished data cited by Pearl and Adams 2005), and the species remains widespread in some areas of the northern and central Oregon Cascades, and it has shown a capacity to rebound from short-term declines (Olson 1992, Brown 1997, Pearl and Adams 2005). In Oregon, 22 percent of historical populations have disappeared (see Fite et al. 1998).

Surveys suggest that R. cascadae remains present in portions of the Trinity Alps and Marble Mountains, California, but are rare to nonexistent in other Californian portions of the historical range (G. Fellers, H. Welsh, personal communications, cited by Pearl and Adams 2005). This species has declined greatly in the vicinity of Lassen Volcanic National Park at the southern end of the range in northern California; a survey of 16 historical sites plus 34 additional sites with suitable habitat yielded only two frogs at a single locality (Fellers and Drost 1993). More recent surveys (1992-2002) detected Cascade frogs at only 4 of 400 sites; population sizes were small at all four sites, and as of 2002, frogs had disappeared from two of these four sites (G. Fellers, personal communication, cited by Pearl and Adams 2005). Jennings and Hayes (1994) and Fellers and Drost (1993) estimated that this species is extirpated from about 99 percent of its southernmost population clusters (Mt. Lassen and surroundings) and 50 percent of the total historical distribution in California.

Intrinsic Vulnerability: Moderately vulnerable

Environmental Specificity: Moderate to broad.

Other NatureServe Conservation Status Information

Global Range: (20,000-200,000 square km (about 8000-80,000 square miles)) Range extends from the Cascade and Olympic mountains of northern Washington south to northern California. Populations in the Olympic Mountains of Washington and the Trinity Alps, Mt. Shasta, and Mt. Lassen areas of California are notably disjunct from the primary distribution along the main Cascade axis (Pearl and Adams 2005). Historical locations at low elevations in Washington suggest that the species formerly may have been more broadly distributed (Leonard et al. 1993). Historical elevational range extended from around 400 to 2,500 meters.

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
Endemism: endemic to a single nation

U.S. & Canada State/Province Distribution
United States CA, OR, WA

Range Map
Note: Range depicted for New World only. The scale of the maps may cause narrow coastal ranges or ranges on small islands not to appear. Not all vagrant or small disjunct occurrences are depicted. For migratory birds, some individuals occur outside of the passage migrant range depicted. For information on how to obtain shapefiles of species ranges see our Species Mapping pages at www.natureserve.org/conservation-tools/data-maps-tools.

Range Map Compilers: IUCN, Conservation International, NatureServe, and collaborators, 2004

U.S. Distribution by County Help
State County Name (FIPS Code)
CA Butte (06007), Lassen (06035), Plumas (06063), Shasta (06089), Siskiyou (06093), Tehama (06103), Trinity (06105)
OR Clackamas (41005), Deschutes (41017), Douglas (41019), Jackson (41029), Josephine (41033), Klamath (41035), Lane (41039), Linn (41043), Multnomah (41051), Wasco (41065)
WA Chelan (53007)+, Clallam (53009)+, Clark (53011)+, Cowlitz (53015)+, Grays Harbor (53027)+, Jefferson (53031)+, King (53033)+, Kittitas (53037)+, Klickitat (53039)+, Lewis (53041)+, Mason (53045)+, Pierce (53053)+, Skagit (53057)+, Skamania (53059)+, Snohomish (53061)+, Whatcom (53073)+, Yakima (53077)+
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
17 Lake Chelan (17020009), Wenatchee (17020011), Upper Yakima (17030001), Naches (17030002), Lower Yakima, Washington (17030003), Middle Columbia-Hood (17070105), Upper Deschutes (17070301)+, Little Deschutes (17070302)+, Lower Deschutes (17070306)+, Lower Columbia-Sandy (17080001)+, Lewis (17080002), Upper Cowlitz (17080004), Lower Cowlitz (17080005), Middle Fork Willamette (17090001)+, Mckenzie (17090004)+, North Santiam (17090005)+, Molalla-Pudding (17090009)+, Clackamas (17090011)+, Hoh-Quillayute (17100101), Queets-Quinault (17100102), Lower Chehalis (17100104), North Umpqua (17100301)+, South Umpqua (17100302)+, Upper Rogue (17100307)+, Illinois (17100311)+, Upper Skagit (17110005), Sauk (17110006), Stillaguamish (17110008), Skykomish (17110009), Snoqualmie (17110010), Snohomish (17110011), Lake Washington (17110012), Duwamish (17110013), Puyallup (17110014), Nisqually (17110015), Skokomish (17110017), Hood Canal (17110018), Dungeness-Elwha (17110020), Crescent-Hoko (17110021)
18 Williamson (18010201)+, Upper Klamath Lake (18010203)+, Lost (18010204)+, Butte (18010205)+, Upper Klamath (18010206)+, Shasta (18010207)+, Scott (18010208)+, Lower Klamath (18010209)+, Salmon (18010210)+, Trinity (18010211)+, Lower Pit (18020003)+, Mccloud (18020004)+, Sacramento headwaters (18020005)+, North Fork Feather (18020121)+, Cow Creek (18020151)+, Battle Creek (18020153)+*, Thomes Creek-Sacramento River (18020156)+*, Big Chico Creek-Sacramento River (18020157)+, Butte Creek (18020158)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Basic Description: A medium-sized frog.
General Description: Most adults are brown to olive-brown and have many distinct black spots on the upper side (black flecks between the spots are scarce or absent), a long yellowish stripe on the upper lip, and a blackish "mask" across the eye and eardrum. Each side of the back has a distinct ridge (dorsolateral fold). The lower abdomen and underside of hind legs are yellow, orange-yellow, or yellowish tan. The groin is usually bright yellow with dark mottling. Lower sides are yellowish or cream. Mature males have a swollen and darkened thumb base and grow to around 60 mm snout-vent length. Females grow larger, to 75 mm. Males produce "chuck-chuck-chuck" or rapid series of clucking calls (several notes per second) during the breeding season; they may call at the water surface or while submerged. Larvae are brown to blackish, with a silvery to brassy underside; they grow to around 5 cm long. Egg massesare rounded clumps of around 300-500 eggs,.deposited singly or often in groups. Primary source: Stebbins (2003).
Diagnostic Characteristics: This species differs from Rana pretiosa in having a less conspicuous light-colored upper jaw stripe, a dark mask, nostrils that are farther apart and lower on the snout, and eyes that are not turned upward as much. It differs from Rana aurora in having distinct black spots on the back, yellowish (rather than red) color on lower abdomen and underside of legs, and generally rougher skin (Stebbins 2003).
Reproduction Comments: Breeds in spring-summer, March to mid-August, soon after ice and snow melt (Stebbins 1985). In a particular pond, most eggs are laid over a period of just a few days. Each female lays a mass of 300-500 eggs, often in aggregations. Larvae metamorphose into small frogs usually about 2-3 months after the eggs were laid. Individuals first breed probably after their third hibernation (Nussbaum et al. 1983). Typical life span is not more than 5 years.
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Mobility and Migration Comments: This species is not known to exhibit well-defined migrations, but it may shift seasonally among different habitats.
Riverine Habitat(s): CREEK, Pool, SPRING/SPRING BROOK
Lacustrine Habitat(s): Shallow water
Terrestrial Habitat(s): Grassland/herbaceous
Special Habitat Factors: Benthic
Habitat Comments: Cascades frogs inhabit wet mountain meadows, sphagnum bogs, ponds, lakes, and streams, in open or patchy coniferous forests. Generally they are closely associated with water, but they sometimes move from one drainage to another by crossing over high mountain ridges. These frogs hibernate in mud at the bottom of ponds and in spring-water saturated ground up to at least 75 meters from a pond (Briggs 1987). Breeding sites are quiet ponds, where eggs are laid in open shallow water or among submerged vegetation.
Adult Food Habits: Invertivore
Immature Food Habits: Herbivore
Food Comments: Adults are mainly invertivorous. Larvae eat algae, detritus, plant tissue, and minute organisms in water.
Adult Phenology: Diurnal, Hibernates/aestivates
Immature Phenology: Diurnal, Hibernates/aestivates
Phenology Comments: This species is inactive during the colder months.
Length: 8 centimeters
Economic Attributes Not yet assessed
Management Summary
Biological Research Needs: An improved understanding of microhabitat associations and interactions with introduced fish is needed to assist with conservation measures for the species (Olson 2001).
Population/Occurrence Delineation
Group Name: Ranid Frogs

Use Class: Not applicable
Subtype(s): Breeding Location
Minimum Criteria for an Occurrence: Occurrences are based on evidence of historical presence, or current and likely recurring presence, at a given location. Such evidence minimally includes collection or reliable observation and documentation of one or more individuals (including larvae or eggs) in or near appropriate habitat where the species is presumed to be established and breeding.
Separation Barriers: Busy major highway, especially at night, such that frogs rarely if ever cross successfully; urban development dominated by buildings and pavement; habitat in which site-specific data indicate the frogs virtually never occur.
Separation Distance for Unsuitable Habitat: 1 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: BARRIERS/UNSUITABLE HABITAT: Rivers may or may not be effective barriers, depending on stream width and flow dynamics; identification of streams as barriers is a subjective determination. Ranid frog species vary in habitat use, but even the most aquatic species may traverse upland habitat when conditions are suitable (Pope and Matthews 2001); natural and seminatural upland habitat generally does not constitute a barrier. Here, unsuitable habitat refers to upland habitat devoid or nearly devoid of wetlands, streams, ponds, or lakes. Bodies of water dominated by predatory fishes may be barriers to some species but suitable habitat for others; in most cases, such waters probably should be regarded as unsuitable habitat.

SUITABLE HABITAT: Suitable habitat includes riparian/riverine corridors, wetlands, and wetland/upland mosaics in which wetland patches are separated by less than 1 km of upland habitat; it also includes any upland habitat regularly used for feeding or wintering (e.g., mesic forest for wood frogs).

MOVEMENTS: Available information indicates that individual ranids occasionally move distances of several km (R. luteiventris: Reaser 1996, cited by Koch et al. 1997; R. blairi: Gillis 1975) but most individuals stay within a few kilometers of their breeding sites (R. aurora draytonii: USFWS, Federal Register, 11 September 2000; R. capito: Franz et al. 1988; R. clamitans: Lamoureux and Madison 1999; R. luteiventris: Turner 1960, Hollenbeck 1974, Bull and Hayes 2001). Similarly, maximum distance between capture points generally is a few kilometers or less (R. aurora: Hayes et al. 2001; USFWS, Federal Register, 11 September 2000; R. catesbeiana: Willis et al. 1956; R. luteiventris: Reaser and Pilliod, in press; Engle 2000; R. muscosa: Pope and Matthews 2001). Dispersal data for juveniles are lacking for most species.

Adult and juvenile R. sylvatica readily traveled in excess of 300 m from their pools of origin (Vasconcelos and Calhoun 2004). Bellis (1965) determined that adult and juvenile R. sylvatica in a peat bog had traveled at least 410 m from the nearest breeding pool. Berven and Grudzien (1990) found that dispersing R. sylvatica juveniles traveled an average of 1,208 m from their natal pools. In the Shenandoah Mountains, data for R. sylvatica indicated that ponds separated by a distance greater than 1,000 m should experience little gene flow (Berven and Grudzien 1991). In contrast, populations in Minnesota were very similar in allelic frequencies, even at distances greater than several kilometers (Squire and Newman 2002). However, sample sizes and number of loci examined were small, and genetic patterns do not necessarily reflect movement distances.

The preponderance of data for ranids indicate that a separation distance of several kilometers may be appropriate for suitable habitat and practical for occurrence delineation, despite occasional movements that are longer and that may allow some genetic interchange between distant populations. The movement data for ranids are here regarded as consistent enough to allow the same separation distance to be used for different species; much of the apparent variation in movements doubtless reflects differences in study methods and in the ability to detect long-distance movements.

Date: 01Apr2005
Author: Hammerson, G.
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
NatureServe Conservation Status Factors Edition Date: 19Dec2011
NatureServe Conservation Status Factors Author: Hammerson, G., and E. Gaines
Element Ecology & Life History Edition Date: 21Dec2010
Element Ecology & Life History Author(s): Hammerson, G.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

  • Adams, M. A., D. E. Schindler, and R. B. Bury. 2001. Association of amphibians with attenuation of ultraviolet-b radiation in montane ponds. Oecologia 128:519-525.

  • Altig, R. and Dumas, P.C. 1971. Rana cascadae.. Catalogue of American Amphibians and Reptiles. 105.1-105.2..

  • Behler, J. L., and F. W. King. 1979. The Audubon Society field guide to North American reptiles and amphibians. Alfred A. Knopf, New York. 719 pp.

  • Blackburn, L., P. Nanjappa, and M. J. Lannoo. 2001. An Atlas of the Distribution of U.S. Amphibians. Copyright, Ball State University, Muncie, Indiana, USA.

  • Blaustein, A. R., J. J. Beatty, D. H. Olson, R. M. Storm. 1995. The biology of amphibians and reptiles in old-growth forests in the Pacific Northwest. General Technical Report. PNW-GTR-337. Pacific Northwest Research Station, Forest Service, Portland, Oregon. 98 pp.

  • Blaustein, A. R., L. K. Belden, D. H. Olson, D. M. Green, T. L. Root and J. M. Kiesecker. 2001. Amphibian breeding and climate change. Conservation Biology 15:1804-1809.

  • Blaustein, A. R., and D. B. Wake. 1990. Declining amphibian populations: a global phenomenon? Trends in Ecology and Evolution 5:203-204.

  • Blaustein, A.R., P.D. Hoffman, D.G. Hokit, J.M. Kiesecker, S.C. Walls and J.B. Hays. 1994. UV repair and resistance to solar UV-B in amphibian eggs: a link to population declines. Proc. Nat. Acad. Sci. 91:1791-1795.

  • Briggs, J. L., Sr. 1987. Breeding biology of the Cascade frog, Rana cascadae, with comparisons to R. aurora and R. pretiosa. Copeia 1987:241-245.

  • Briggs, J.L. and R.M. Storm. 1970. Growth and population structure of the Cascade frog Rana cascadae Slater. Herpetologica 26(3):283-300.

  • Brown, C. 1997. Habitat structure and occupancy patterns of the montane frog, Rana cascadae, in the Cascade Range, Oregon, at multiple scales: implications for population dynamics in patchy landscapes. Master's thesis. Oregon State University, Corvallis.

  • Bury, R.B. 1973. The cascade frog, Rana cascadae, in the north Coast Range of California. Northwest Science. 47:228-229.

  • Crisafulli, C. M., and C. P. Hawkins. 1998. Ecosystem recovery following a catastrophic disturbance: lessons learned from Mount St. Helens. Pages 23-26 in Mac, M. J., P. A. Opler, C. E. Puckett Haecker, and P. D. Doran (editors). Status and trends of the nation's biological resources. Volume 1. U.S. Department of the Interior, U.S. Geological Survey, Reston, Virginia.

  • Davidson, C., H. B. Shaffer, and M. R. Jennings. 2002. Spatial tests of the pesticide drift, habitat destruction, UV-B, and climate-change hypotheses for California amphibian declines. Conservation Biology 16:1588-1601.

  • Dvornich, K.M., K.R. McAllister, and K.B. Aubry. 1997. Amphibians and reptiles of Washington State: Location data and predicted distributions, Vol. 2 in: Washington State Gap Analysis - Final Report, (K.M. Cassidy, C.E. Grue, M.R. Smith and K.M. Dvornich, eds.), Washington Cooperative Fish and Wildlife Research Unit, University of Washington, Seattle, 146 pp.

  • Fellers, G.M. and C.A. Drost. 1993. Disappearance of the Cascades frog RANA CASCADAE at the southern end of its range, California, USA. Biological Conservation 65:177-181.

  • Fite, K. V., A. R. Blaustein, L. Bengston, and H. E. Hewitt. 1998. Evidence of retinal light damage in Rana cascadae: a declining amphibian species. Copeia 1998:906-914.

  • Frost, D. R. 1985. Amphibian species of the world. A taxonomic and geographical reference. Allen Press, Inc., and The Association of Systematics Collections, Lawrence, Kansas. v + 732 pp.

  • Frost, D. R. 2010. Amphibian Species of the World: an Online Reference. Version 5.4 (8 April 2010). Electronic Database accessible at http://research.amnh.org/herpetology/amphibia/index.php. American Museum of Natural History, New York, USA.

  • Green, D.M. 1986a. Systematics and evolution of western North American frogs allied to Rana aurora and Rana boylii: karyological evidence. Systematic Zoology 35:273-282.

  • Green, D.M. 1986b. Systematics and evolution of western North American frogs allied to Rana aurora and Rana boylii: electrophoretic evidence. Systematic Zoology 35:283-296.

  • Green, David M. 1985. Natural Hybirds Between the Frogs Rana Cascadae and Rana Pretiosa (Anura: Ranidae). Herpetologica 41(3):262-267.

  • Hatch, A. C., L. K. Belden, E. Scheessele and A. R. Blaustein. 2001. Juvenile amphibians do not avoid potentially lethal levels of urea on soil substrate. Environmental Toxicology and Chemistry 20:2328-2335.

  • Jennings, M. R., and M. P. Hayes. 1994. Amphibian and reptile species of special concern in California. Final Report submitted to the California Department of Fish and Game, Inland Fisheries Division. Contract No. 8023. 255 pp.

  • Jones, L.L.C., W. P. Leonard, and D. H. Olson, editors. 2005. Amphibians of the Pacific Northwest. Seattle Audubon Society, Seattle, Washington. xii + 227 pp.

  • Karlstrom, E. L. 1986. Amphibian recovery in the North Fork Toutle River debris avalanche area of Mt. St. Helens. Pages 334-344 in Keller, S.A.C. (editor). Mount St. Helens: five years later. Eastern Washington University Press, Cheney, Washington.

  • Kiesecker, J. M., and A. R. Blaustein. 1997. Influences of egg laying behavior on pathogenic infection of amphibian eggs. Conservation Biology 11:214-220.

  • Leonard, W. P., H. A. Brown, L. L. C. Jones, K. R. McAllister, and R. M. Storm. 1993. Amphibians of Washington and Oregon. Seattle Audubon Society, Seattle, Washington. viii + 168 pp.

  • Macey, J. R., J. L. Strasburg, J. A. Brisson, V. T. Vredenburg, M. Jennings, and A. Larson. 2001. Molecular phylogenetics of western North American frogs of the Rana boylii species group. Molecular Phylogenetics and Evolution 19:131-143.

  • Marco, A., and A. R. Blaustein. 1999. The effects of nitrite on behavior and metamorphosis in Cascades frogs (Rana cascadae). Environmental Toxicology and Chemistry 18:946-949.

  • Nussbaum, R.A., E.D. Brodie, Jr., and R.M. Storm. 1983. Amphibians and Reptiles of the Pacific Northwest. University Press of Idaho, Moscow, Idaho. 332 pp.

  • Olson, D. H. 1992. Ecological susceptibility of amphibians to population declines. Pages 55-62 in Harris, R. R., and D. E. Erman (technical coordinators), and Kerner, H. M. (editor). Biodiversity of northwestern California. Proceedings of a Symposium 28-30 October 1991, Santa Rosa, California. University of California Wildland Resource Center Report, Number 29, Davis, California.

  • Olson, D. H. 2001. Ecology and management of montane amphibians of the U.S. Pacific Northwest. Biota 2:51-74.

  • Palen, W. J., D. E. Schindler, M. J. Adams, C. A. Pearl, R. B. Bury, and S. A. Diamond. 2002. Optical characteristics of natural waters protect amphibians from UV-B in the U.S. Pacific Northwest. Ecology 83:2951-2957.

  • Pearl, C. A., and M. J. Adams. 2005. Rana cascadae Slater, 1939. Pages 538-540 in M. Lannoo, editor. Amphibian declines: the conservation status of United States species. University of California Press, Berkeley.

  • Stebbins, R. C. 1951. Amphibians of western North America. University of California Press, Berkeley. 539 pp.

  • Stebbins, R. C. 1985a. A field guide to western reptiles and amphibians. Second edition. Houghton Mifflin Company, Boston, Massachusetts. xiv + 336 pp.

  • Stebbins, R. C. 2003. A field guide to western reptiles and amphibians. Third edition. Houghton Mifflin Company, Boston.

  • Sype, W.E. 1975. Breeding habits, embryonic thermal require-ments and embryonic and larval developments of the Cascade frog, Rana cascadae Slater. Ph.D. Thesis, Oregon State Uni- versity, Corvallis, 113 pp.

  • Tyler, T. J., C.D. McIntire, B. Samora, R. L. Hoffman and G. L. Larson. 2002. Inventory of aquatic breeding amphibians, Mount Rainier National Park, 1994-1999. National Park Service, Final report, U.S. Forest and Rangeland Ecosystem Science Center, Corvallis, Oregon.

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Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:

Full metadata for the Mammal Range Maps of North America is available at:

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