Many Texans are concerned about encountering dangerous wildlife, especially amphibians in their backyards. This article clarifies the presence of toxic amphibians in Texas and provides actionable information to help residents understand and manage potential risks.
Understanding Amphibian Toxicity
The terms “poisonous” and “venomous” are often used interchangeably, but they describe different ways toxins are delivered. An animal is venomous if it injects toxins, typically through a bite or sting. A poisonous animal releases toxins when touched or ingested. Most amphibians, including frogs and toads, are poisonous because they secrete defensive compounds from their skin glands that act as a chemical defense against predators.
Specialized glands, such as the parotoid glands behind the eyes of toads, produce a milky substance containing various toxic compounds. These natural chemicals, often called bufotoxins, can cause harm if they contact mucous membranes or are ingested. Amphibians release these toxins when threatened or handled.
The Primary Concern: Cane Toads in Texas
While Texas has numerous amphibian species, and some frogs like the pickerel frog possess mild skin irritants, the Cane Toad (Rhinella marina) poses the most significant toxic threat to humans and pets. Also known as the Giant Toad or Marine Toad, this large amphibian is native to extreme southern Texas, extending through Central and South America. It has also been introduced to other regions, including parts of Florida.
Cane Toads thrive in various habitats, including urban and suburban environments, particularly near bodies of water. Their potent bufotoxins can be fatal to pets and native wildlife, and cause irritation in humans. These toxins are present throughout the toad’s life cycle, from eggs and tadpoles to adults, and remain toxic even in dead toads. When threatened, Cane Toads can squirt this milky substance from their parotoid glands.
Identification and Safety Measures
Identifying a Cane Toad is crucial for safety. Adult Cane Toads are large, ranging from 4 to 9 inches, with warty skin that can be tan to reddish-brown with dark spots. A distinguishing feature is the presence of prominent, triangular-shaped parotoid glands behind their eyes. Unlike some native Texas toads, Cane Toads lack distinct cranial crests (bony ridges) on their heads.
If a person contacts Cane Toad secretions, immediate first aid is recommended. For skin exposure, remove contaminated clothing and thoroughly flush the affected skin with cool running water, then wash gently with soap and water. If the toxin gets into the eyes, gently flood them with water for at least 15 minutes, ensuring eyelids are held open. If swallowed, carefully clean the mouth with a toothbrush or cloth and seek medical attention if symptoms like vomiting, dizziness, or chest pain develop.
Pets, especially dogs, are highly susceptible to Cane Toad poisoning due to their tendency to mouth or lick toads. Symptoms in pets include excessive drooling, red gums, head-shaking, crying, loss of coordination, vomiting, and in severe cases, seizures, collapse, or death. If you suspect your pet has encountered a Cane Toad, immediately wipe their mouth and gums thoroughly with a wet cloth, gently rubbing to remove the sticky toxin. Avoid hosing out the pet’s mouth, as this can lead to accidental inhalation and pneumonia. Seek immediate veterinary attention, as prompt treatment significantly improves outcomes.
Preventative measures can significantly reduce the risk of encounters. Keep pets on a short leash, especially during dusk and dawn when toads are most active, to prevent them from investigating toads. Remove potential hiding spots in your yard, such as debris piles and tall weeds, and trim shrubs so their branches are off the ground. Turning off outdoor lights at night also helps, as these lights attract insects, which in turn attract toads.
Pet food and water bowls should not be left outdoors, as toads may contaminate them with toxins. Properly dispose of any found dead toads by burying them deeply or placing them in the garbage to prevent secondary poisoning.