Woodhouse toads ( Anaxyrus woodhousii) are common amphibians found across a wide range of North American habitats, from central and western United States into Mexico and even parts of Canada. These adaptable creatures often inhabit areas near water sources like rivers, lakes, and irrigation ditches, and can even be found in suburban backyards and under streetlights. Many people wonder about the potential hazards these toads might pose to humans and pets due to their defensive mechanisms.
Understanding Woodhouse Toad Defenses
Woodhouse toads are not “poisonous” in the sense of being toxic if ingested like a mushroom. Instead, they possess specialized glands that secrete defensive compounds. Prominent parotoid glands located behind their eyes discharge a milky, irritating, and toxic secretion when the toad is threatened.
The primary toxins in these secretions are bufotoxins, a group of compounds including bufogenins, which are similar to cardiac glycosides. These substances act as neurotoxins and cardiotoxins, designed to deter predators by causing an unpleasant or harmful reaction if absorbed through mucous membranes or ingested. This makes the toad unpalatable, encouraging predators to release them quickly.
Recognizing Symptoms of Exposure
Exposure to Woodhouse toad secretions can lead to various symptoms in both pets and humans. For pets, especially dogs and cats who might mouth or lick a toad, immediate signs often include excessive drooling and foaming at the mouth. Pets may also paw at their mouth, gag, or retch, and vomiting is common. More severe symptoms can include disorientation, weakness, difficulty walking, muscle tremors, seizures, or collapse. Abnormal heart rhythms and elevated potassium levels (hyperkalemia) can also develop in severe cases.
Humans typically experience less severe reactions. Direct skin contact can cause irritation, while eye contact may lead to irritation or temporary visual changes. If secretions are transferred to the mouth and ingested, mild gastrointestinal upset, such as nausea or vomiting, can occur. The severity of symptoms in both pets and humans depends on the amount of toxin absorbed and individual sensitivity.
What to Do After Contact
Immediate action is important if a human or pet comes into contact with Woodhouse toad secretions. For pets, first, promptly separate them from the toad. Thoroughly rinse the pet’s mouth with a damp cloth or wet rag, wiping the gums, tongue, and inside of the lips to remove the sticky toxin. Avoid using a strong stream from a hose, as this can lead to accidental aspiration of water into the lungs. After rinsing, seek veterinary attention promptly, especially if symptoms are severe or progress beyond mild drooling.
For humans, if skin contact occurs, wash the affected area thoroughly with soap and water. If secretions get into the eyes, rinse them with clean water for several minutes. If symptoms persist, are severe, or if ingestion is suspected, contact poison control or a medical professional for guidance. Prompt treatment and observation can help manage adverse reactions effectively.
Coexisting with Woodhouse Toads
Living alongside Woodhouse toads involves understanding their behaviors and taking preventative measures. These toads are primarily nocturnal, active at night, especially after rain or in warm, humid weather. Supervising pets outdoors, particularly during these times, can prevent curious interactions. Discouraging pets from investigating or playing with toads is an effective prevention strategy.
Woodhouse toads are beneficial for pest control, as they primarily feed on insects and other small invertebrates, including those attracted to outdoor lights. Identifying Woodhouse toads can help differentiate them from other amphibians; they typically have rough, warty skin, prominent parotoid glands behind their eyes, and often a narrow light-colored stripe down their back. Observe these amphibians from a distance to avoid contact with their defensive secretions.