All toads secrete a toxic substance through their glands, which are on the skin. Some toads are more poisonous than others, secreting higher amounts of toxic when they are threatened.
A pet that licks or eats a toad, will absorb the toxins through their mouths, which will cause poisoning.
If you happen to touch a toad, ensure you wash your hands thoroughly before you touch anything else.
The 18 poisonous toads include:
1. American Toad
American toads (Anaxyrus Americanus) are large and can grow to 4.25 inches (10.7cm) with a gray, olive, brown, or brick red body with a light mid-dorsal stripe.
There is dark pigment visible on the chest and at the front of the back, close to the head.
The males have dark throats and are smaller than the female.
They are common throughout North America, though they are not usually encountered in the southern most states. They can adapt to their environment, which is close to a semi-permanent water source.
These nocturnal toads are common in fields, barnyards, lawns, and gardens. They hide under woodpiles, porches, under boards, and stones.
2. Colorado River Toad
Colorado River Toads (Incilius Alvarius) are also known as Sonoran Desert Toads and are common in the southwestern United States and Northern Mexico.
These large toads can grow to 7.5 inches (19cm) and is the largest toad you can encounter in the United States (apart from the non-native cane toad).
The skin is leathery, but smooth, usually in olive green or brown mottled color. They have a kidney-shaped gland just behind their golden eye with white glands on the legs, all of which produce toxic secretion.
Dogs that have attacked these toads have suffered from paralysis and death.
This toad is found in southeastern California, New Mexico, southern Arizona, and Mexico. It can live in a semi-arid area or desert, though they are semi-aquatic and are usually encountered near springs, drainage ditches, and canals.
3. Argentine Toad
The Argentine toad (Rhinella Arenarum) belongs to the Bufonidae family and is common in southern Brazil, Uruguay, and Paraguay. They are have also been encountered in Argentina.
They live in small ponds with stagnant water and in dry areas with open areas.
4. Asian Giant Toad
Asian giant toads (Phrynoidis Asper) are also known as river toads and are native to southeast Asia.
This medium-sized toad is green, brown, black, or dark gray in color with tubercles all over.
Females are larger than males and can grow to 5.5 inches (14cm) with males growing to around 3.9 inches (10cm).
Being partially aquatic and nocturnal, they are not often encountered, usually only coming out at night, hiding under submerged stones during the daytime. They are never found further than two meters from the water.
They reproduce throughout the year with large clutches, averaging around 12,000 eggs per clutch.
5. Colombian Giant Toad
The Colombian giant toad (Rhaebo Blombergi) is a large toad that belongs to the Bufonidae family, usually found in rain forests up to 2,130 feet.
They are common in Colombia and Ecuador. There was a recording of a Colombian giant toad in Florida in 1963 but was not established.
This is one of the largest toads in the world with females growing to 9.8 inches (25cm) and males to 6.7 inches (17cm).
They have been captured as pets with females laying up to 80.000 eggs with an average lifespan of ten years in captivity.
The Colombian Giant Toad prefers lowland tropical forests where they breed in pools.
They are collected for the pet trade and are experiencing habitat loss, which is why they are considered near threatened by IUCN (International Union for Conservation of Nature).
6. Western Toad
Western toads (Anaxyrus Boreas) are large toads that grow up to 5.1 inches (13cm).
They are native to the western parts of North America, usually seen on wet nights and close to water.
For a toad, they can jump fair distances.
They can be identified by the cream dorsal stripe on a green or gray background with dark patches. The male’s skin is smoother than the female with fewer patches. In juveniles, the dorsal stripe may not be visible or may be very faint.
The Western toad can be found from British Colombia to Alaska, Washington, Oregon, Idaho, Baja California, Montana, Wyoming, Nevada, and Colorado.
They live in a range of habitats from riparian forests to areas with plenty of willows and shrubs. In California, they seem to prefer riparian forests with open water and dry mountain meadows. In Nevada, they prefer pine forests, oak woodlands, and scrubs.
7. European Toad
The European Toad (Bufo Bufo), also known as the Common Toad is found throughout most of Europe, except Iceland and Ireland, along with Mediterranean Islands.
They hide during the day and become active at dusk, hunting during the night.
They are slow movers that walk and jump a short distance.
They are gray to brown with warts covering their bodies.
They are solitary until the breeding season when they come together at breeding ponds, with the males competing for females.
They can grow to 6 inches (15cm) with females being broader than the male.
They have broad heads with wide moths with two small nostrils with bulb-like eyes. Their broad bodies sit close to the ground with short forelimbs.
They can live many years with the oldest recorded being fifty years in captivity. They live up to twelve years in the wild.
They live up to 8,200 feet in the southern part of their range and are usually found in woodlands, wet locations, open countrysides, parks and gardens, and fields.
8. Asiatic Toad
Asiatic toads (Bufo Gargarizans) are common throughout China, parts of Russia, and southern Japan.
They are common in open forests, cultivated areas, meadows, and grasslands where it is humid. They are seldom found higher than 800 meters.
9. African Common Toad
African common toads (Sclerophrys Gutturalis) belong to the Bufonidae family and are common in Africa, from Angola and Botswana to South Africa, Zimbabwe Mauritius, and Mozambique.
They prefer tropical to subtropical forests, dry savannas, shrublands, grasslands, intermittent rivers, marshes, pastures, rural gardens, urban areas, and canals and ponds.
These large toads can grow to 4.7 inches (12cm) for females and 3.5 inches (9cm) for males.
They are brown with irregular dark brown patches with brown spots between the eyes and a pale stripe that runs down their spine. Their throats are dark and they have a red patch o their thighs.
10. Japanese Common Toad
Japanese common toads (Bufo Japonicus) belong to the Bufonidae family and are endemic to Japan where they live in forests, shrubland, marshes, swamps, springs, rural gardens, and irrigated land.
These toads are large and can grow to 7 inches (17.5cm) with females being larger than the male.
They have pointed snouts, robust bodies, and short forelimbs. The skin has warts with varying colors from dark brown to a yellow or green-brown with webbing between their toes.
These toads are common in Japan, living in a variety of habitats from mountainous areas to lowland areas.
11. Fowler’s Toad
The Fowler’s toad (Anaxyrus Fowleri) is native to North America and belongs to the Bufonidae family. It is found in the eastern United States and parts of Canada.
These toads are olive green-brown gray or rust-red with wart-like spots. There is a pale stripe on the back and a white belly with one dark spot.
They grow to 3.7 inches (9.5cm) and their tadpoles can grow to 0.55 inches (1.4cm) in length.
They live in sand prairies, beaches, open woodlands, and meadows where they are busy underground during the day and in winter.
12. Cane Toad
Cane toads (Rhinella Marina) are also known as marine toads and are large toads that are native to southern and mainland Central America, though they have also been introduced to the Caribbean Islands and Northern Australia.
They are the largest of the true toads in the world.
This is an old species of toad that are opportunistic eaters. They grow to 6 inches (15cm) with females being slightly larger than the male.
These toads have poison glands and their tadpoles are also highly toxic. They are very dangerous to dogs.
Female cane toads are longer than males and grow to 6 inches (15cm) and can live for up to fifteen years in the world.
In captivity, the oldest specimen lived thirty-five years.
They have dry and warty skin with ridges above the eyes. They range from red-brown to olive-brown and gray to yellow with varying patterns.
They can be found in south Texas, Florida, and Hawaii. The introductions to Louisiana were unsuccessful. They were used to control sugarcane pests in 1936 and 1944 in Florida.
13. Asian Common Toad
The Asian common toad (Duttaphrynus Melanostictus) is widely distributed throughout South and Southeast Asia, growing to 8 inches (20cm) with black tadpoles.
The head has bony ridges with a short and blunt snout. The toes have a half web with the first finger being longer than the second. They have spiny warts on their dorsal side, which are brown to yellow with the ridges and spines being black.
Males have a vocal sac and black pads on the inside of the fingers.
These toads are common from north Pakistan to Bangladesh to Sri Lanka, Thailand, Vietnam, Cambodia, Macau, and Malaysia, to name a few.
They have been found up to 5,900 feet above sea level, preferring lowland habitats, including river banks, urban areas, and beaches.
14. Cuban Toad
The Cuban toad (Peltophryne Peltocephala) is a red/brown to brown color with a brown head and cream chin and lower lip. They have banded legs.
These toads can grow to 16.3cm for females and 12.8cm for males. Juveniles are different from adults with a green to red-brown dorsum with three pairs of patches and a black interocular triangle.
The Cuban toad is endemic to Cuba where it can be found from sea level to moderate elevations living in cultivated fields, stream banks, rural houses, and forests. It is also sometimes found along the ocean.
These toads are nocturnal and remain hidden under rocks, drain pipes, trash, and soil cracks during the day. Males form choruses on the ground, close to slow running steams and ditches.
15. Oak Toad
The oak toad (Anaxyrus Quercicus) belongs to the Bufonidae family and is endemic to the coastal regions in the southeastern parts of the United States.
This is the smallest toad species in North America and grows to 1.30 inches (3.3cm).
They have a light mid-dorsal stripe with brown and black spots. Females are larger than males and do not have a vocal sac. Males have a clear white belly and a vocal sac, while females have a dark-spotted belly and no vocal sac.
Their natural habitat includes pine flat woods, pine-oak woods, savannas with sandy soil, maritime forests, and oak scrub. They are common across the coastal plains of southeastern United States from Florida to southeast Virginia and eastern Louisiana.
16. African Common Toad
The African common toad (Sclerophrys Regularis) is found in Subsaharan Africa, ranging from Libya and Algeria to Egypt, Congo, Cameroon, Senegal, Kenya, and Nigeria, to name a few.
This sturdy toad is large with wart-like skin with males growing to 3.6 inches (9.1cm) and females being larger, growing to 5.1 inches (13cm). Males have a vocal sac under their chin. These toads are dark to olive-brown with patches on their backs and a pale band down the spine.
They tend to bounce when threatened, which confuses predators, giving them time to escape. They can move through water with webbed hind feet.
They are found in abundance in grasslands, savannas, forests, and agricultural habitats, usually close to a river where they breed.
17. Gulf Coast Toad
Gulf coast toads (Incilius Valliceps) are native to eastern and southeastern Mexico and Central America.
This medium-sized toad can grow to 4 inches (10.2cm) varying in color from black to brown or gray with yellow or white stripes down the center o their back and some light-colored patches on the sides. Their belly is cream to yellow with small tubercles on their backs.
They live in a range of habitats from open grasslands to forests and backyards. They are usually close to a permanent water source, where they breed in the springtime.
18. European Green Toad
European green toads (Bufotes Viridis) are found in mountainous areas, deserts, urban areas, and other habitats in Europe, from France to Western Russia.
They have green to dark brown spots on their backs with a light-colored belly. They can change color as a response to light and heat changes with females being larger than the male. Females can lay up to 15,000 eggs at a time.
These toads can grow to 3.9 inches (10cm). They eat a variety of invertebrates and insects including crickets, butterflies, moths, beetles, and caterpillars.