CHIHUAHUAN GREEN TOAD
Anaxyrus debilis (Girard 1854)
ăn-ăx-ī'-rŭs — dĕb-ĭh'-lĭs


Conservation Status:

State: Kansas Threatened Species

Federal: None
NatureServe State: S2 - Imperiled
NatureServe National: N4 - Apparently Secure
NatureServe Global: G5 - Secure
CITES: None

An adult female Chihuahuan Green Toad from Wallace County, Kansas. © Travis W. Taggart.
An adult female Chihuahuan Green Toad from Logan County. Image © Suzanne L. Collins, CNAH.
An adult female Chihuahuan Green Toad from Logan County, Kansas. Image by Travis W. Taggart.
An adult female Chihuahuan Green Toad from Logan County, Kansas. Image by Travis W. Taggart.
An adult female Chihuahuan Green Toad from Logan County, Kansas. Image by Travis W. Taggart.
Ventral view of a male Chihuahuan Green Toad from Logan County. © Travis W. Taggart.
An adult Chihuahuan Green Toad (UMMZ 67442) collected in Logan County in 1929. Image © Travis W. Taggart.
A tadpole of Bufo debilis. Image © Altig et al. (2006).

Description:
A tiny flat toad with a dorsal color of green or yellow with small black spots that occasionally fuse to form bars or reticulations. The ventral surface is white or cream with occasional small black spots on the chest. The throats of chorusing males are black. The parotoid glands are oval. Females grow larger than males. The tadpole labial tooth row formula of 2/2 is unique and apomorphic for A. debilis and its closest relatives (A. kelloggi from western mainland Mexico, and A. retiformis from Arizona and adjacent Sonora, Mexico.
Adults are normally 32-50 mm (1¼- 2 inches) in snout-vent length. The largest Kansas specimen is a female (KU 5652) from Morton County with a snout-vent length of 44 mm (1 ¾ inch) collected by Theodore E. White and Edward H. Taylor on 15 August 1928. The maximum length throughout the range is 2¼ inches (Conant and Collins, 1998).

Distribution:
The Chihuahuan Green Toad is currently restricted to rangeland/canyon systems above the Smoky Hill River and Ladder Creek drainages in Greeley, Logan, Wallace, and Wichita counties. The historic range was probably continuous (except for the sandy alluvial valley of the Arkansas River) from Logan and Wallace/Sherman counties south to the nearest populations in northwestern Oklahoma, northern Texas, northeastern New Mexico, and southeastern Colorado. Prior to the mid-1800s this area consisted of short-grass prairies interspersed with playa wetlands but has since been altered by cultivation and landscape and drainage modifications to point that they cannot support Chihuahuan Green Toads.
The reports from Morton County (Cragin 1894; Taylor 1929; Hill 1931; KU 5643-54; MVZ 43326) were all taken before the Dust Bowl conditions of the 1930s. Other locations reported (but without extant voucher specimens) or from localities too imprecise to plot are Grant County (KU 5642; Kellogg 1932), Hamilton County (Cragin 1894; see Remarks), and Barber County (Cragin 1894).
The Kansas Department of Wildlife, Parks, and Tourism has designated critical for Chihuahuan Green Toads in Morton, Logan, and Wallace counties.
(, Museum Voucher) (, Observation) (, Literature Record)
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  • Occurrence Summary:  
  • 196
    Records 
  • 112
    Museum Vouchers 
  • 84
    Other Observations 
Some county occurrences indicated below may be too imprecise to map above.
County Breakdown: County Name (# occurrences):
Grant (1); Greeley (15); Hamilton (1); Logan (102); Morton (15); Sherman (1); Wallace (60); Wichita (1);

Natural History:
Chihuahuan Green Toads often take refuge under rocks or in existing rodent or other burrows. They currently inhabit open native grassland plains and canyon systems in Kansas (as much of their upland prairie habitats have been lost to cultivation).
Stimulated by late spring and summer rains, males begin their move to ephemeral breeding sites where they begin chorusing. Females follow the chorusing males to the breeding site. Reproduction occurs in stock ponds, wallows, playas, pools along intermittent streams, and flooded ditches. Males start calling starting at sunset, however, during the peak of activity, chorusing may be heard intermittently during the day. Chorusing often takes place in the water, especially among vegetation near the edge, but may also occur several feet from the breeding site. Most chorusing occurs from late May through late August (Sullivan, 1984; Degenhardt et al., 1996, Taggart (1997). In Kansas, Taylor (1929) reported chorusing on 8 August in Morton County. Taggart (1997) observed chorusing as early as 12 June and as late as 2 September in Wallace and Logan counties.
Breeding aggregations usually only last 2-3 days, however, subsequent significant precipitation events are each likely to trigger successive breeding attempts. Taggart (1997) reported a single clutch of 1,287 non-adhesive eggs laid by a female while in amplexus. The eggs were laid singly and no egg-strings (though strings have been reported elsewhere) were observed in the clutch. Twenty-five ova averaged 0.98 mm and another sample of 32 (measured before preservation) averaged 1.15 mm. Eggs are attached to weeds and grass.
The length of the larval stage is uncertain and is dependent upon numerous environmental factors, most notably the water temperature. Strecker (1926) suggested metamorphosis took fewer than 3 weeks. Burkhart (1984) estimated larval life exceeded 25 days in Kansas, while Taggart (1997) observed development from zygote to juvenile in 8 days. Metamorphosis is complete at about 19.05 mm (3/4 inches) snout-vent length.
Newly transformed toadlets often hide in the deep fissures formed in the high clay-content mud of the drying pools (Seymour, 1972; Creusere and Whitford, 1976; Taggart, 1997). Creusere and Whitford (1976) reported that juvenile Chihuahuan Green Toads remained at the hatching site for 55 days, using vegetation as cover and fissures in the soil to avoid desiccation.

Occurrence Activity:
The blue dates denote chorusing actity. The red dates are other occurrences. The darker a date is, the greater the relative number of observations for that date.
Chorusing:

Audio recording by Keith Coleman.

Chorusing Phenology: The black outlined dots denote the Julian date (day of the year; 1 January = 1 to 31 December = 365) an observation was made. The thin red line depicts the range of dates between the beginning of the first, and end of the fourth quartile (excluding outliers; Tukey method). The thick light blue bar represents the second and third quartile (interquartile range; the middle 50% of all observations). Only one observation per Julian date is included in the graphs; so a date with multiple observations carries the same weight as a date with only one observation. The vertical bars correspond to the 12 months of the year; January through December.
# Unique Obervations: 92; Range: 05 May to 09 Sep; Interquartile range: 25 Jun to 13 Aug;

Observation Type: (of recorded types)
Remarks:
The Chihuahuan Green Toad was first reported in Kansas by Cragin, (1894). The earliest existing specimen is from 1911(KU 5642). It was once more widespread in Kansas than recent records indicate. The populations in west-central Kansas were probably continuous with populations to the south and west (excluding the Arkansas River sand prairies) prior to the intensive dry-land farming practices utilized up to the Dust Bowl of the 1930s.
Stan Roth (Roth and Collins, 1979) rediscovered (UMMZ 67442 collected in Logan County in 1929 [no other locality]) a disjunct population along the Smoky Hill River in Wallace County, and soon after populations to the east in Logan County (Burkhart, 1984) were reported. Ultimately, Chihuahuan Green Toads were found just to the south of these sites along the Ladder Creek Drainage in Greeley and Wichita counties, Taggart (1997). These northern populations are isolated from other known populations and represent the only extant populations of this taxon in Kansas.
Within the northern populations, the greatest abundance of this species is found on chalk flat prairies, Ogallala outcrops, and associated breaks along the Smoky Hill River drainage in Logan and Wallace counties.
Records from Hamilton, Morton, and Grant counties are in need of verification. The Hamilton County record (Cragin, 1894; Smith, 1934, 1950) may represent a Stanton County observation. Cragin, 1894 reported that "... the species was observed a few days later in great abundance and activity (during rainy weather) in Morton county[sic], Kansas, and in the southern part of Hamilton county[sic]" during 1886. Stanton County was founded in 1887 and that area was part Hamilton County prior.  The records reported from Hamilton County by Taggart, 1997 are in error, as those specimens were actually from Greeley County. Kellogg, 1932, lists a specimen from Greeley County (@ KU; 9 mi. NE of Tribune) and six specimens from Logan County (KSC [Kansas State University] 50-55; no listed locality) that have been lost. Cragin (1884), reported an observation from Barber County, but no voucher exists and there are no corroborating reports within 100 miles.
A repatriation effort was initiated by the Kansas Department of Wildlife and Parks (Taggart, 1997) to introduce the species back into managed areas of their former range in Kansas. Releases were made in 1991, 1992, and 1993 at several sites in the Cimarron National Grassland. Despite annual surveys at the release sites since 2001, no Chihuahuan Green Toads have been re-discovered.
The nearest extralimital populations of Chihuahuan Green Toads are along the Cimarron River in Oklahoma (~40 miles upstream from Kansas) and along the Arkansas River drainage in Colorado (~60 miles upstream from Kansas). Futures surveys for this species in Kansas should include more surveys in Morton, Hamilton, Stanton, Sherman, and Grant counties.
A population genetic analysis comparing the northern populations with those from other parts of its range is currently underway and may yield interesting taxonomic implications and phylogeographic patterns for the isolated extant population in west-central Kansas. That population has been likely isolated by the Arkansas River drainage (sand prairies) for the past 10 million years.
Where the Chihuahuan Green Toad occurs in Kansas, it appears to be thriving and is the most commonly observed Anaxyrus under suitable conditions.
Listed as a Kansas Threatened species in 1987. No recovery plan has been completed for this species.
As defined by Kansas Administrative Regulations, critical habitats include those areas documented as currently supporting self-sustaining population(s) of any threatened or endangered species of wildlife as well as those areas determined by the Kansas Department of Wildlife, Parks, and Tourism to be essential for the conservation of any threatened or endangered species of wildlife.
Currently, the following areas are designated critical for Chihuahuan Green Toads:
(1) All native prairie lands and waters within an area encircled by a line beginning on the Logan-Wichita County line at SE corner Sec. 36, T15S, R37W, then extending due north to the Smoky Hill River at Sec. 24, T13S, R37W, then continuing westerly along the Smoky Hill River to the Kansas Highway K-27 crossing at Sec. 27, T13S, R40W, Wallace County, then southerly along Kansas Highway K-27 to the Wallace-Greeley County line at SW corner Sec. 35, T15S, R40W, then due east along the county lines to the point of origin at SE corner Sec. 36, T15S, R37W. This area contains lands and waters in Logan and Wallace counties.
(2) All suitable habitat within the Cimarron National Grasslands in Morton County.


Bibliography:
1854 Girard, Charles. A list of the North American Bufonids, with diagnoses of new species. Proceedings of the Academy of Natural Sciences, Philadelphia 7():86-88
1894 Cragin, Francis W. Herpetological notes from Kansas and Texas. Colorado College Studies Fifth Annual Publication():37-39
1929 Taylor, Edward H. List of reptiles and batrachians of Morton County, Kansas, reporting species new to the state fauna. University of Kansas Science Bulletin 19(6):63-65
1932 Kellogg, Remington. Mexican tailless amphibians in the United States National Museum . Bulletin of the United States National Museum (160):1-224
1933 Smith, Hobart M. The Amphibians of Kansas Thesis. University of Kansas, Lawrence. 383pp.
1934 Smith, Hobart M. The Amphibians of Kansas. American Midland Naturalist 15(4):377-527
1943 Bragg, Arthur N. and Charles Clinton Smith. Observations on the ecology and natural history of anura IV: The ecological distribution of toads in Oklahoma. Ecology 24(3):285-309
1950 Smith, Hobart M. Handbook of Amphibians and Reptiles of Kansas. University of Kansas, Museum of Natural History, Miscellaneous Publication (2):336
1953 Schmidt, Karl P. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.
1962 Bogert, Charles M. Isolation mechanisms in toads of the Bufo debilis group in Arizona and Western Mexico. American Museum Novitates (2100):1-37
1970 Zweifel, Richard G. Descriptive notes on larvae of toads of the debilis group, genus Bufo. American Museum Novitates (2407):1-13
1974 Collins, Joseph T. Amphibians and Reptiles in Kansas University of Kansas Museum of Natural History Public Education Series (1):283 pp
1976 Rundquist, Eric M. Field checklist (of) amphibians and reptiles of Kansas. Kansas Herpetological Society, Lawrence. pp.
1977 Perry, Janice. Kansas herps needed. Kansas Herpetological Society Newsletter (18):2-3
1979 Roth, Stanley D. and Joesph T. Collins. Geographic distribution: Bufo debilis insidior. Herpetological Review 10():118
1979 Rundquist, Eric M. The status of Bufo debilis and Opheodrys vernalis in Kansas Transactions of the Kansas Academy of Science 82(1):67-70
1982 Collins, Joseph T. Amphibians and Reptiles in Kansas. 2nd edition. University of Kansas Museum of Natural History Public Education Series (8):
1984 Burkhart, Jeffery T. Status of the Western Green Toad (Bufo debilis insidior) in Kansas. Kansas Fish and Game Commission, Agency Contract No. 72. 25pp.
1988 Busby, William H. The Kansas Natural Heritage Program: Taking stock of Kansas' natural heritage. Kansas Herpetological Society Newsletter (71):9-12
1989 Simmons, John E. Endangered and threatened in Kansas. Kansas Herpetological Society Newsletter (75):4-5
1990 Collins, Joseph T. Maximum size records for Kansas amphibians and reptiles. Kansas Herpetological Society Newsletter (81):13-17
1991 Collins, Joseph T. and Suzanne L. Collins. Reptiles and Amphibians of the Cimarron National Grasslands, Morton County, Kansas. U. S. Forest Service, Elkhart, Kansas. 60pp.
1991 Conant, Roger and Joseph T. Collins. Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America. 3rd ed. Houghton Mifflin Company, Boston, Massachusetts. pp.
1992 Collins, Joseph T. New records of amphibians and reptiles in Kansas for 1991. Kansas Herpetological Society Newsletter (87):12-17
1992 Rundquist, Eric M. Kansas endangered, threatened, and SINC species. Kansas Herpetological Society Newsletter (91):
1992 Taggart, Travis W. Bufo debilis. Geographic distribution. Herpetological Review 23():85
1992 Taggart, Travis W. Observations on Kansas amphibians and reptiles Kansas Herpetological Society Newsletter (88):13-15
1992 Taggart, Travis W. Observations on Kansas amphibians and reptiles. Kansas Herpetological Society Newsletter (88):13-15
1992 Taggart, Travis W. Results of the KHS annual field trip to Sheridan County State Lake. Kansas Herpetological Society Newsletter (90):3-4
1993 Collins, Joseph T. and Suzanne L. Collins. Amphibians and Reptiles in Kansas. Third Edition. University Press of Kansas, Lawrence, Lawrence. 397pp.
1994 Taggart, Travis W. The natural history and distribution of the Green Toad (Bufo debilis) in Kansas, with a report on an effort to reintroduce the species into the Cimarron National Grasslands. Kansas Department of Wildlife and Parks, Pratt. 12pp.
1995 Moriarty, Emily C. and Joseph T. Collins. First known occurrence of amphibian species in Kansas. Kansas Herpetological Society Newsletter (100):28-30
1996 Rakestraw, J. Spring herp counts: A Kansas tradition. Reptile & Amphibian Magazine (March-April):75-80
1997 Taggart, Travis W. Status of Bufo debilis (Anura: Bufonidae) in Kansas Kansas Herpetological Society Newsletter (109):7-12
1998 Conant, Roger and Joseph T. Collins. Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America. 3rd ed, expanded. Houghton Mifflin Company, Boston, Massachusetts. pp.
2002 Kingsbury, Bruce and Joanna Gibson. Habitat Management Guidelines for Amphibians and Reptiles of the Midwest. Publication of Partners in Amphibian and Reptile Conservation, Address not given. 152pp.
2003 Taggart, Travis W. Logan County herp count. Journal of Kansas Herpetology (7):8
2004 Taggart, Travis W. Kansas Herpetological Society 2004 spring field trip. Journal of Kansas Herpetology (9):2
2006 Frost, Darrel R, 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, Jonathan A. Campbell, Boris L. Blotto, Paul Moler, Robert C. Drewes, Ronald A. Nussbaum, John D. Lynch, David M. Green, and Ward C. Wheeler. The amphibian tree of life Bulletin of the American Museum of Natural History (297):370
2006 Taggart, Travis W. Distribution and status of Kansas herpetofauna in need of information. State Wildlife Grant T7. Kansas Department of Wildlife and Parks, Pratt. vii + 106pp.
2007 Taggart, Travis W., Joseph T. Collins, and Curtis J. Schmidt. Estimates of amphibian, reptile, and turtle mortality if Phostoxin is applied to 10,000 acres of prairie dog burrows in Logan County, Kansas. Kansas Department of Wildlife and Parks, Pratt. 5pp.
2009 Collins, Joseph T., Suzanne L. Collins, and Travis W. Taggart. A follow-up evaluation of two anuran repatriations in southeastern and southwestern Kansas. Kansas Department of Wildlife and Parks, Pratt. 15pp.
2010 Collins, Joseph T., Suzanne L. Collins, and Travis W. Taggart. Amphibians, Reptiles, and Turtles of Kansas Eagle Mountain Publishing., Provo, Utah. 400pp.
2011 Collins, Joseph T., Suzanne L. Collins, and Travis W. Taggart. Amphibians, Reptiles, and Turtles of the Cimarron National Grassland, Kansas. Second (Revised) Edition. U. S. Forest Service, . pp.
2011 Taggart, Travis W. Results of the Kansas Herpetological Society 2011 Summer Field Trip to Scott State Park Journal of Kansas Herpetology (39):2
2011 Taggart, Travis W. and Daniel Murrow. KHS to conduct summer field trip to western Kansas. Journal of Kansas Herpetology (38):5
2012 Rohweder, Megan R. Spatial conservation prioritization of Kansas for terrestrial vertebrates. Thesis. Fort Hays State University, Hays, Kansas. 151pp.
2014 Taggart, Travis W. Recent scientific and standard English name changes effecting the Kansas herpetofauna. Collinsorum 3(2-4):9-10
2015 Rohweder, Megan R. Kansas Wildlife Action Plan. Ecological Services Section, Kansas Department of Wildlife, Parks and Tourism in cooperation with the Kansas Biological Survey. 176pp.
2016 Powell, Robert, Roger Conant, and Joseph T. Collins. Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America. Houghton Mifflin Harcourt, Boston. 494pp.
2017 Taggart, Travis W. and J. Daren Riedle. A Pocket Guide to Kansas Amphibians, Turtles and Lizards. Great Plains Nature Center, Wichita, Kansas. 69pp.
2020 Riedle, J. Daren. Revisiting Kansas Herpetological Society field trip and Herp Count data: Distributional patterns and trend data of Kansas amphibians and reptiles. Collinsorum 9(1):7-16
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8/26/2020 11:14:57 AM