Red-spotted Toad, Anaxyrus punctatus

Red-spotted Toad, Anaxyrus punctatus. A fairly common house mate in the greater Los Cabos area, Baja California Sur.  Size:  9.0 cm (3.5 inches).

Red-spotted Toad, Anaxyrus punctatus. Found is a fresh water river in the greater East Cape area of Baja California Sur, December 2017. Size:  10.5 cm (4.1 inches). Catch courtesy of Kyle Rousseau, Maple Ridge, British Columbia, Canada. Photograph courtesy of Brad Murakami, Surrey, British Columbia, Canada.

The Red-spotted Toad, Anaxyrus punctatus, is a member of the Bufonidae family of Toads. The Bufonidae family consists of twelve members placed into three genera. There are twenty-three species in the Anaxyrus genus. The Red-spotted Toad is known in Mexico as Sapo de Puntos Rojos.

Red-spotted Toads have a flattened head and body that is covered with warty, glandular skin. Their snout is pointed and their cranial crests are either weak or absent. Their eyes are metallic gold with horizontal black pupils. They have small, round parotid glands that are about the same size as their eyes. They are olive, brown, or gray dorsally with red-tipped warts, which gives them their name. Their ventral surface is white or cream in color and may or may not have spotting. Sexual dimorphism is displayed with males growing to a smaller size and typically being darker than the females. Additionally, females typically display lighter colored throats. Sexual maturity is attained at approximately 4.7 cm (1.9 inches) and 5.2 cm (2.0 inches) in snout to vent length in males and females, respectively. 

Red-spotted Toads are primarily nocturnal, spending their days under rocks or in crevices, and emerge at dusk to forage and mate. Occasionally, they may be observed moving around in daylight or resting at the edge of breeding pools during the breeding season. Red-spotted Toads in canyons and mountains tend to breed from March through May, while populations in lowland sites and valleys tend to breed during the summer rains from late June or July into September. Reproduction occurs in pools, springs, temporary ponds, intermittent streams, and cattle tanks. Breeding at streams may span two to four weeks, while breeding triggered by rainfall at temporary rain pools may span one to five nights. During this time, males defend breeding territories through wrestling. Males also produce a mating call to advertise their fitness to prospective females from various locations at their breeding site. This mating call consists of a single-pitched trill that lasts two to ten seconds. Males and females pair up in amplexus and fertilization is external, with the male releasing sperm as the female lays eggs. Females lay anywhere from 50 to 3,000 eggs underwater, with an average of 1,500 eggs per clutch. Red-spotted Toads are the only toads in North America that lay eggs individually, instead of in a long gelatinous string. The adults leave soon after copulation and no additional parental care is provided to the offspring. The eggs hatch in a few days and the tadpoles are black in color with metallic bronze flecks. Tadpoles reach approximately 40 mm in length and metamorphosize in six to eight weeks. Red-spotted Toads live less than six years in the wild, with an average lifespan of approximately two years.

Red-spotted Toads are slow moving, often using a walking or crawling motion with short hops. They are good climbers and can easily navigate rocky terrain. Red-spotted Toads primarily consume a variety of invertebrates, however, cannibalism has also been documented in this species. They locate their prey visually, before lunging with their large, sticky tongue to catch the prey and drag it into their mouth. In turn, they are preyed upon by hawks, coyotes, owls, raccoons, and foxes. Tadpoles are primarily herbivorous and are preyed upon by salamanders, fish, aquatic insects, and birds. If conditions become unfavorable, Red-spotted Toads can survive a 40% loss of body water. Their elevational range extends from near sea level to approximately 2,270 m (7,450 feet). They occupy Sonoran desert scrub, Chihuahuan desert scrub, semi-desert and plains grassland, oak and pine-oak woodlands, coastal and foothill thorn scrub, and tropical deciduous forest. Red-spotted Toads are typically found at or near places they breed including springs, ciénegas, streams, temporary pools, or tinajas that fill with the summer rains. Although they are often found on the edge of agriculture, they do not thrive within agricultural areas. 

The Red-spotted Toad may be confused with the California Toad, Anaxyrus boreas halophilus, due to their similar appearances and overlapping ranges. These species can be differentiated visually and geographically. California Toads are greenish, tan, dusky gray, or yellow in color with significant dark blotching and a light stripe along their spine. Additionally, California Toads are only found throughout most of central and southern California into western Nevada.

From a conservation perspective, the Red-spotted Toad is currently considered to be of Least Concern due to their wide distribution and presumed large population size. There currently appears to be no major threats to this species. Despite being found in the international pet trade, current levels do not constitute a major threat to the species.