Some frogs use bluff or deception

Some frogs, such as the poison dart frogs, are especially toxic. The native people of South America extract poison from these frogs to apply to their weapons for hunting,[142] although few species are toxic enough to be used for this purpose. At least two non-poisonous species of frogs in tropical America (Eleutherodactylus gaigei and Lithodytes lineatus) mimic the colouration of dart poison frogs for self-protection.[143][144] Some frogs obtain poisons from the ants and other arthropods they eat.[145] Others, such as the Australian corroboree frogs (Pseudophryne corroboree and Pseudophryne pengilleyi), can synthesize the alkaloids themselves.[146] The chemicals involved may be irritants, hallucinogens, convulsants, nerve poisons or vasoconstrictors. Many predators of frogs have become adapted to tolerate high levels of these poisons, but other creatures, including humans who handle the frogs, may be severely affected.[147]

Some frogs use bluff or deception. The European common toad (Bufo bufo) adopts a characteristic stance when attacked, inflating its body and standing with its hindquarters raised and its head lowered.[148] The bullfrog (Rana catesbeiana) crouches down with eyes closed and head tipped forward when threatened. This places the parotoid glands in the most effective position, the other glands on its back begin to ooze noxious secretions and the most vulnerable parts of its body are protected.[103] Another tactic used by some frogs is to "scream", the sudden loud noise tending to startle the predator. The gray tree frog (Hyla versicolor) makes an explosive sound that sometimes repels the shrew Blarina brevicauda.[103] Although toads are avoided by many predators, the common garter snake (Thamnophis sirtalis) regularly feeds on them. The strategy employed by juvenile American toads (Bufo americanus) on being approached by a snake is to crouch down and remain immobile. This is usually successful, with the snake passing by and the toad remaining undetected. If it is encountered by the snake's head, however, the toad hops away before crouching defensively