Red-spotted Toad (Anaxyrus punctatus)
Red-Spotted-Toad ©2013 Dancing Snake Nature Photography.
Photo by Robert Bezy and Kathryn Bolles
Red Spotted Toad, Photo by Warren Savary
Red-spotted Toad calling. Imperial Co., CA. Photo by Jim Rorabaugh.
Red-spotted Toads in amplexus, Deep Canyon, Riverside Co., CA. Photo by Jim Rorabaugh.
Red-spotted Toad, Photo by Young Cage.
Red-spotted Toad, Photo by Young Cage.
Red-spotted Toad tadpoles and metamorph. Near Lake Havasu City, AZ. Photo by Blythe Watt.
This is a moderate-sized toad (<76 mm SVL) that is brown or gray dorsally, usually with red-tipped dorsal tubercles, particularly in juveniles. The parotoid glands are small and round, usually about the same size as the eyes. The head is relatively flat and the cranial crests are weak or absent. Sexual maturity is attained at about 47 mm and 52 mm SVL in males and females, respectively. Males grow to a slightly smaller size and are generally darker in color than the females; males also have a darkened throat. Metamorphs are 10-18 mm SVL.
This is one of the most commonly-encountered amphibians in the 100-Mile Circle, and can be found from low desert tinajas and pools in arroyos upwards in elevation to pine-oak woodlands. However, unlike some other species of toads and frogs, it is not frequently found in agriculture. It occurs throughout the 100-Mile Circle except for the tops of the highest mountains and the Sulphur Springs Valley. The species is primarily nocturnal, but some individuals, especially metamorphs, are active by day. Red-spotted Toads in canyons and mountains tend to breed from March through May, while toads in lowland sites or valleys breed during the summer rains from late June or July into September. Breeding males call from exposed places in shallow water or from land near breeding sites and engage in territorial wrestling matches with other males. The call is a single-pitched trill lasting 2-10 seconds, which can be heard at:
From 50 to 3,000 eggs are laid singly, some of which may clump together into small masses, which then hatch in a few days; most metamorphose in 6-8 weeks. Larger tadpoles, which grow to about 40 mm total length, are black with metallic bronze flecks. Red-spotted Toads primarily consume a variety of invertebrates such as beetles, bees, bugs, and ants; however, cannibalism has been documented. The tadpoles are mostly herbivorous. Hybridization with other toads, including the closely related Sonoran Green Toad, as well as the Sinaloa Toad, Great Plains Toad, and Woodhouse’s Toad, has been reported.
This is a species of least concern on the IUCN’s Red List. There is no reason to believe the Red-Spotted Toad has declined in wildlands within the 100-Mile Circle; however, it has declined or been eliminated in highly developed areas, such as urban environments and croplands. Most of the literature on this species is under the name Bufo punctatus. Frost et al. (2006) subdivided former Bufo into several genera, including Anaxyrus, although that classification has met with some opposition by herpetological systematists.
Bradford, D.E., A.C. Neale, M.S. Nash, D.W. Sada, and J.R. Jaeger. 2003. Habitat patch occupancy by toads (Bufo punctatus) in a naturally fragmented desert landscape. Ecology 84:1012-1023.
Brennan, T.C., and A.T. Holycross. 2006. Amphibians and Reptiles in Arizona. Arizona Game and Fish Department, Phoenix, AZ.
Degenhardt, W.G., C.W. Painter, and A.H. Price. 1996. Amphibians and Reptiles of New Mexico. University of New Mexico Press, Albuquerque.
Frost, D.R., T. Grant, J. Faivovich, R.H. Bain, A. Haas, C.F.B. Haddad, R.O. De Sá, A. Channing, M.Wilkinson, S.C. Donnellan, C.J. Raxworth, J.A. Campbell, B.L. Blotto, P. Moler, R.C. Drewes, R.A. Nussbaum, J.D. Lynch, D.M. Green, and W.C. Wheeler. 2006. The amphibian tree of life. Bulletin of the American Museum of Natural History 297:1-370.
Sullivan, B.K. 2005. Bufo punctatus Baird and Baird, 1852 Red-Spotted Toad. Pages 430-432 in M.J. Lannoo (editor), Amphibian Declines: The Conservation Status of United States Species. University of California Press, Berkeley.
Author: Jim Rorabaugh
For additional information on this species, please see the following volume and page in the Sonoran Herpetologist: 1999 Oct:106.