The Colorado River toad, also known as the Sonoran Desert toad, is a large amphibian native to the southwestern United States and northern Mexico. It typically measures about 4 to 7 inches in length and has a distinctive olive-green or brown coloration with warty skin. This toad is primarily nocturnal and prefers habitats near rivers, streams, and other water sources. The Colorado River toad is known for its unique defense mechanism: it secretes a potent toxin from its parotoid glands. This toxin can be harmful to predators and is sometimes harvested for its psychoactive properties. However, the toad's population is threatened by habitat loss and pollution, making conservation efforts important.