The Sonoran Desert Toad, also known as the Colorado River Toad (Incilius alvarius), is poisonous to humans. This amphibian secretes potent toxins from glands on its skin, a defense mechanism against predators. Exposure can lead to significant health issues, from mild irritation to severe systemic effects. It is important to understand these risks and prevent accidental contact.
Identifying the Sonoran Desert Toad
The Sonoran Desert Toad is one of the largest native toads in North America, typically reaching lengths of 4 to 7.5 inches (11 to 18.7 cm) and weighing almost two pounds. Its skin is relatively smooth for a toad, often appearing greenish-gray to dark brown, sometimes with small brownish or orange spots. A distinguishing feature includes prominent, elongated parotoid glands located behind each eye, which are visible as large, bulging, kidney-shaped structures. Additionally, it has a white wart near the corner of its mouth and large warts on its hind legs.
These toads are common across the Sonoran Desert region, inhabiting areas from central Arizona to southwestern New Mexico and northern Mexico. They prefer arid and semi-arid environments, often found near permanent or temporary water sources such as streams, springs, canals, and rain pools. Sonoran Desert Toads are primarily nocturnal, becoming most active during the summer rainy season from late May to September. During hot or cold periods, they often seek refuge in rodent burrows.
The Nature of Its Toxicity
The Sonoran Desert Toad’s defense mechanism involves secreting a milky, white substance from its parotoid glands when threatened. This substance contains a complex mixture of potent toxins, including the psychoactive compounds 5-MeO-DMT (5-methoxy-N,N-dimethyltryptamine) and bufotenin.
The toad’s secretions are toxic when ingested or absorbed through mucous membranes. Contact with skin, especially if it enters the mouth, nose, or eyes, can lead to poisoning.
Symptoms of Exposure in Humans
Exposure to the Sonoran Desert Toad’s toxins can result in a range of symptoms, varying in severity based on contact level and individual sensitivity. Direct skin contact can cause irritation, while ingestion or contact with mucous membranes leads to more systemic effects. Initial symptoms often include numbness, tingling, and excessive salivation.
More severe reactions involve gastrointestinal distress like nausea and vomiting. Neurological symptoms may include dizziness, confusion, disorientation, and potent hallucinations. The toxins can also affect the cardiovascular system, leading to a rapid or irregular heartbeat. In serious cases, individuals might experience seizures, difficulty breathing, or respiratory distress, with potential for coma or cardiac arrest if large quantities are ingested.
Immediate Actions and Prevention
If you suspect exposure to the Sonoran Desert Toad’s toxins, immediate action is important. Thoroughly wash the affected area with soap and water to remove any remaining secretions. Avoid touching your eyes, nose, or mouth, as this can spread toxins to mucous membranes, exacerbating symptoms. After cleaning, seek immediate medical attention by contacting emergency services or poison control, providing details of the exposure.
Preventing contact involves several practical measures. Educate children and pets about the dangers of handling wildlife, supervising them closely outdoors, especially at night when these toads are most active. Secure your home and yard to prevent toads from entering, which may include installing fine-mesh fencing or removing standing water sources that attract them, such as pet water bowls left outside. Being cautious in areas where they reside, particularly near water features or during the monsoon season, can further reduce the risk of accidental contact.