Gulf Coast Toad (Incilius nebulifer)
Description and Morphological Characteristics
The Gulf Coast Toad is a relatively flat toad ranging 2-4 inches in length. Color can vary between individuals but most are generally dark brown, almost black, with touches of deep orange to yellow-brown, with whitish spots across the dorsum. They feature a dark, broad, lateral stripe on either side, and a light stripe down the middle of the back that begins on the head. A more distinguishing characteristic of this species is the very prominent cranial crest which forms a deep valley between the eyes. They have triangular parotoid glands that connect to the crest just behind the eye and most have a distinct, dark, narrow line which runs the length of the upper lip. The throat of males is yellow-green while females lack pigment, and both sexes have a yellowish or cream-colored venter.
Range
The native range of this species extends from extreme south-eastern Mississippi through east-central Texas and south into Mexico. They are abundant throughout their range, especially along the Gulf Coast of Texas and Louisiana. Some disjunct populations have been found in Arkansas and northern Louisiana, possibly as a result of dispersal along river systems.
Habitat and Feeding
Gulf Coast Toads can be found in a wide variety of natural habitats including forests, swamps, barrier beaches, and coastal prairies. They are also common to urban areas and are often found in railroad, roadside, and irrigation ditches, storm sewers, backyards, and gardens. They have adapted well to urban environments and thrive so long as their habitat provides ample moisture and cover. During the daytime they can be found under vegetative debris and other sources of cover such as concrete slabs. They feed on various species of insects and are commonly seen near streetlights and porch lights where flying insects are active, especially at twilight.
Breeding and Reproduction
Breeding is triggered by rainfall events and occurs from March to September. Males form choruses and congregate at breeding sites which include ponds, temporary wetlands, roadside ditches, and other still-water habitats. Their advertisement call is a short flat trill that lasts 2-6 seconds and is repeated several times. Females lay their eggs in strings of jelly, in double rows, and clutches can contain up to 20,000 eggs. Tadpoles hatch 1-2 days after deposition and take approximately 20-30 days to metamorphose. Juveniles live in habitats similar to that of adults, but may remain near their natal ponds for some time before they disperse.
Conservation
Gulf Coast Toads are widespread and abundant throughout their range and are considered very common. They are not under federal protection at this time but are included in the White List from Texas Parks and Wildlife.
Pertinent References
Alexander, L. G., Lailvaux, S. P., Pechmann, J. H. K., and DeVries, P. J. 2012. Effects of Salinity on Early Life Stages of the Gulf Coast Toad, Incilius nebulifer (Anura: Bufonidae). Copeia 2012:106-114.
Mendelson, J. R. III. 2005. Coastal Plain Toad. Pp. 424-427 in M. Lannoo (Ed.), Amphibian Declines: The Conservation Status of United States Species. University of California Press, USA.
Saenz, D., Fitzgerald, L.A., Baum, K.A., and Conner, R.N. 2006. Abiotic correlates of anuran calling phenology: the importance of rain, temperature, and season. Herpetological Monographs 20:64-82.
Account Author: Hailey Hester
Photos: James Childress
Edited by Christopher Schalk
The Gulf Coast Toad is a relatively flat toad ranging 2-4 inches in length. Color can vary between individuals but most are generally dark brown, almost black, with touches of deep orange to yellow-brown, with whitish spots across the dorsum. They feature a dark, broad, lateral stripe on either side, and a light stripe down the middle of the back that begins on the head. A more distinguishing characteristic of this species is the very prominent cranial crest which forms a deep valley between the eyes. They have triangular parotoid glands that connect to the crest just behind the eye and most have a distinct, dark, narrow line which runs the length of the upper lip. The throat of males is yellow-green while females lack pigment, and both sexes have a yellowish or cream-colored venter.
Range
The native range of this species extends from extreme south-eastern Mississippi through east-central Texas and south into Mexico. They are abundant throughout their range, especially along the Gulf Coast of Texas and Louisiana. Some disjunct populations have been found in Arkansas and northern Louisiana, possibly as a result of dispersal along river systems.
Habitat and Feeding
Gulf Coast Toads can be found in a wide variety of natural habitats including forests, swamps, barrier beaches, and coastal prairies. They are also common to urban areas and are often found in railroad, roadside, and irrigation ditches, storm sewers, backyards, and gardens. They have adapted well to urban environments and thrive so long as their habitat provides ample moisture and cover. During the daytime they can be found under vegetative debris and other sources of cover such as concrete slabs. They feed on various species of insects and are commonly seen near streetlights and porch lights where flying insects are active, especially at twilight.
Breeding and Reproduction
Breeding is triggered by rainfall events and occurs from March to September. Males form choruses and congregate at breeding sites which include ponds, temporary wetlands, roadside ditches, and other still-water habitats. Their advertisement call is a short flat trill that lasts 2-6 seconds and is repeated several times. Females lay their eggs in strings of jelly, in double rows, and clutches can contain up to 20,000 eggs. Tadpoles hatch 1-2 days after deposition and take approximately 20-30 days to metamorphose. Juveniles live in habitats similar to that of adults, but may remain near their natal ponds for some time before they disperse.
Conservation
Gulf Coast Toads are widespread and abundant throughout their range and are considered very common. They are not under federal protection at this time but are included in the White List from Texas Parks and Wildlife.
Pertinent References
Alexander, L. G., Lailvaux, S. P., Pechmann, J. H. K., and DeVries, P. J. 2012. Effects of Salinity on Early Life Stages of the Gulf Coast Toad, Incilius nebulifer (Anura: Bufonidae). Copeia 2012:106-114.
Mendelson, J. R. III. 2005. Coastal Plain Toad. Pp. 424-427 in M. Lannoo (Ed.), Amphibian Declines: The Conservation Status of United States Species. University of California Press, USA.
Saenz, D., Fitzgerald, L.A., Baum, K.A., and Conner, R.N. 2006. Abiotic correlates of anuran calling phenology: the importance of rain, temperature, and season. Herpetological Monographs 20:64-82.
Account Author: Hailey Hester
Photos: James Childress
Edited by Christopher Schalk