Craugastor augusti (Dugès, 1879)
Barking Frog, Western Barking Frog (C. a. cactorum), Eastern Barking Frog (C. a. latrans)
© 2015 Rafael Alejandro Calzada-Arciniega (1 of 23)
Eleutherodactylus augusti (Dugés, 1879)
Cecil R. Schwalbe
1. Historical versus Current Distribution. Barking frogs (Eleutherodactylus augusti) were first described from Guanajuato, Mexico, by Dugés in 1868 (field notes can be found in Brocchi, 1882). In the United States they were first described from southwestern Texas (Cope, 1878b). Most of the range of barking frogs is in Mexico, from Oaxaca up through the Sierra Madre Occidental and Oriental into the United States (Zweifel, 1967). Barking frogs are now known to range into southeastern Arizona, southeastern and south-central New Mexico, and western and central Texas (Bezy et al., 1966; Degenhardt et al., 1996; Dixon, 2000; Murray and Painter, 2003). In Arizona, barking frogs have been documented in the Santa Rita (Slevin, 1931), Pajarito (Bezy et al., 1966), Huachuca (Schwalbe et al., 1997), and Quinlan (Enderson, 2002) Mountains at elevations of 1,280–1,890 m. There is also report of a barking frog caught in the Sierra Ancha of central Arizona (Wright and Wright, 1949). In New Mexico, barking frogs are documented in Doña Ana, Chaves, Eddy, and Otero counties between elevations of 900–1,200 m (Degenhardt et al., 1996; Murray and Painter, 2003). In Texas, barking frogs are distributed along the Balcones Escarpment (Smith and Buechner, 1947) and are found in isolated populations throughout the western panhandle (Dixon, 2000).
Currently, barking frogs in Texas and New Mexico are members of the subspecies E. a. latrans and barking frogs in Arizona belong to the subspecies E. a. cactorum (Zweifel, 1956a), but there has been taxonomic confusion with this group. These subspecies were originally considered separate species (Taylor, 1938b), but Zweifel (1956a) combined them into a single species due to their lack of morphological distinctiveness. Before this analysis, barking frogs from Texas, New Mexico, and Arizona were all considered to be members of the species E. latrans (Wright and Wright, 1949; Stebbins, 1951). Differences in call structure between barking frogs in Arizona and those in New Mexico and Texas suggest that Eleutherodactylus augusti may currently represent more than one species (C.G., B. Sullivan, J. Malone, and Goldberg et al., 2004a. Barking frog fossils have been found in late Pleistocene deposits in a cave in Bexar County, Texas (Mecham, 1958), and in middle Holocene deposits in a limestone cave in Kerr County, Texas (Parmley, 1988b). A comparison of historical versus current distributions is not possible due to lack of information, but we are not aware of any reports of extirpations from former localities. For barking frog distribution in Mexico, see Hardy and McDiarmid (1969), Webb (1984), and references in Zweifel (1967).
2. Historical versus Current Abundance. Abundance of barking frogs in a canyon in the Huachuca Mountains of southern Arizona has remained steady since 1993, based on call counts (1993–2002) and mark–recapture analysis (1996–2000; Goldberg and Schwalbe, 2000; C.G., unpublished data). No other information is available.
3. Life History Features.
i. Breeding migrations. In Arizona, barking frogs moved up to 50 m from overwintering to calling sites at the beginning of the breeding season (Goldberg and Schwalbe, 2000). There is some speculation that males may lead females to a predetermined nest site (Arizona Game and Fish Department, 1999c).
ii. Breeding habitat. Barking frogs usually call from rock fissures and crevices in the rock outcrops they occupy ( Jameson, 1954; Schwalbe et al., 1997; Goldberg and Schwalbe, 2000). They have also been observed calling from under vegetation and in the open (B. Alberti, C.G., C.R.S., unpublished data).
i. Egg deposition sites. Females likely deposit eggs in moist or rain-filled cracks, fissures, and caves (Wright and Wright, 1949). Eggs may also be deposited in moist earth under rocks (Jameson, 1950b). ii. Clutch size. Clutches contain from 50–76 eggs (Wright and Wright, 1949; McAlister, 1954; Degenhardt et al., 1996). One clutch contained eggs with diameters of 8–8.5 mm (Valett and Jameson, 1961).
C. Direct Development. Complete metamorphosis occurs within the egg; young hatch fully developed (Jameson, 1950b). Hatching is estimated to occur after 25–35 d of development in Texas ( Jameson, 1950b); anecdotal evidence from Arizona suggests that one clutch may have hatched in 21 d (Goldberg and Schwalbe, 2000).
i. Brood sites. Unknown.
ii. Parental care. Jameson (1950b) hypothesized that male barking frogs guard the egg clutch and maintain moisture levels by excretion. However, radio-tracking data from Arizona suggest that males move too frequently to guard eggs and that females may stay with the clutch (Goldberg and Schwalbe, 2000).
D. Juvenile Habitat. Juveniles are found in the same general areas as adults (Strecker, 1933; Radke, 1998; C.R.S., unpublished data). However, immediately before and during onset of a 6 hr rainstorm, five hatchlings were found along a footpath at least 30 m from the nearest substantial rock outcrop in the Sierra de Alamos (Sonora, Mexico; C.R.S., personal observations).
E. Adult Habitat. Barking frogs are terrestrial and commonly found in or near cliffs, caves, and limestone or other rock outcrops in a variety of biotic communities (Smith and Buechner, 1947; Wright and Wright, 1949; Bezy et al., 1966; Reddell, 1971). In Arizona, barking frogs have been found on limestone, rhyolite, and other rock outcrops in Madrean evergreen woodland (Bezy et al., 1966; Goldberg and Schwalbe, 2004a). In New Mexico and west Texas, barking frogs are found in creosote bush flats near rodent burrows on gypsum soils (Degenhardt et al., 1996; Bartlett and Bartlett, 1999b). In central Texas, barking frogs are found in juniperoak scrub forest (Blair, 1950) on or near limestone outcrops (Conant and Collins, 1998). In Mexico, barking frogs are found in a variety of biotic communities, from xeric, yucca-covered hills (Martin, 1958) to open pine forests (Duellman, 1961). Barking frogs have been found in caves and abandoned mines throughout their range (Reddell, 1971; Hubbard et al., 1979; Goldberg and Schwalbe, 2000; C.R.S., personal observations).
F. Home Range Size. In Arizona, the average 95% kernel home range size of 10 barking frogs was 1,087 m2 (95% C.I. 518–2,327 m2; range 207–5,498 m2; Goldberg and Schwalbe, 2004b).
G. Territories. There is no indication that barking frogs are territorial in Arizona. We have observed two males calling from the same rock crevice simultaneously on at least two occasions (C.G., personal observations). Frogs with overlapping home ranges use the same crevices as daytime refugia, but not simultaneously (Goldberg and Schwalbe, 2000). At least four overwintering (aestivating) frogs have been found piled into a single crevice (C.G. and coworkers, unpublished data; see “Aestivation/ Avoiding Desiccation” below).
H. Aestivation/Avoiding Desiccation. In Arizona, barking frogs have been observed to be active in an abandoned mine throughout the winter (dry season), except for the warm, wet summer, when they are surface active. Barking frogs in the Huachuca Mountains of southern Arizona leave winter (dry season) refugia just before the start of the summer rains and return from August–October (Goldberg and Schwalbe, 2000). In Texas, barking frogs are active at any time of year when there is sufficient ground moisture (Jameson, 1954).
I. Seasonal Migrations. In Arizona, barking frogs moved from 12–50 m between summer activity areas and overwintering sites (Goldberg and Schwalbe, 2000).
J. Torpor (Hibernation). Unknown. Likely in more exposed microsites in northern portions of their range.
K. Interspecific Associations/Exclusions. In Texas, barking frogs have sympatric distributions and shared habitat characteristics with cliff chirping frogs (E. marnockii; Jameson, 1954). Barking frogs have also been found near Gulf Coast toads (Bufo valliceps [now considered to be Coastal-Plain toads, B. nebulifer; see Mulcahy and Mendelson, 2000; Mendelson, this volume]), cliff chirping frogs, and within the same cave as a western slimy salamander (Plethodon albagula; McAlister, 1954). In Mexico, barking frogs have been found near Eleutherodactylus (=Syrrhophus) dennisi (Martin, 1958), E. vocalis (Webb, 1960), and red-spotted toads (Bufo punctatus; C.R.S., unpublished data). Barking frogs and E. hidalgoensis may exclude each other from areas in Tamaulipas, Mexico (Martin, 1958).
L. Age/Size at Reproductive Maturity. Adult size ranges from 47–94 mm (Wright and Wright, 1949; Zweifel, 1956a; Anderson and Lidicker, 1963). Adult females in the Huachuca Mountains of Arizona were larger than males by an average of 7.1 mm (Goldberg and Schwalbe, 2000). Males in Arizona have dark tympana and adult males have dark throats during the calling season; females have pink tympana and white throats year-round (Goldberg and Schwalbe, 2000).
M. Longevity. Unknown, but the same adults in Arizona have been caught yearly for 7 yr (Goldberg and Schwalbe, 2004a; unpublished data). An adult from Sonora, Mexico, lived in captivity for 11 yr at the Arizona-Sonora Desert Museum.
N. Feeding Behavior. In the wild, barking frogs have been known to eat camel crickets (Ceuthophilus sp.), field crickets (Acheta assimilis), Gladston grasshoppers (Melanoplus gladstoni), longhorned katydids (Tettiganiidae), short-horned grasshoppers (probably Acrididae), land snails (Bulimului sp. and Succinea sp.), silverfish (Lepisma saccharina), centipedes (Scolopendra sp.), scorpions (Vaejovis sp.), kissing bugs (Triatoma sp.), spiders, and adult ant lions (Hesperoleon niger; McAlister, 1954; Olson, 1959; Schwalbe et al., 1997; Radke, 1998; Goldberg and Schwalbe, 2000). In captivity, barking frogs have eaten cave crickets (Pholeogryllus geertsi; Olson, 1959) and cliff chirping frogs (Jameson, 1955).
O. Predators. Unknown. P. Anti-Predator Mechanisms. Upon capture, barking frogs will swell to increase their size and avoid predation (Wright and Wright, 1949; McAlister, 1954; Martin, 1958). Barking frogs in Texas have skin secretions that are irritating to the eyes and to open cuts (Wright and Wright, 1949; McAlister, 1954), but this is apparently not the case with Arizona frogs (C.G., personal observations). Barking frog females from Texas and Puebla, Mexico, will screech when hand-captured (Taylor, 1938b; Jameson, 1954); females from Arizona do not display this behavior (unpublished data).
Q. Diseases. Unknown.
R. Parasites. Unknown.
Barking frogs have no special protection
at the state or federal level. They
are considered a Species of Special Concern
in Arizona (Arizona Game and Fish
Department, 1996a) which does not
provide any legal protection. There is
no evidence of decline in the only Arizona
population studied (Goldberg and
Schwalbe, 2000), but data are unavailable
to assess status on a larger scale.
The secretive habits of barking frogs
make detection difficult; their distribution
in Arizona is still largely unknown.
Known barking frog localities in Arizona
are on Forest Service and National
Park Service properties. In New Mexico
and Texas, barking frog populations are
mostly located on private lands, but
they are also found on state, Fish and
Wildlife Service, and National Park Service
properties (Degenhardt et al., 1996;
Radke, 1998; Murray and Painter,
Literature references for Amphibian Declines: The Conservation Status of United States Species, edited by Michael Lannoo, are here.
Feedback or comments about this page.
Citation: AmphibiaWeb. 2023. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 11 Dec 2023.
AmphibiaWeb's policy on data use.