When threatened the terratail thrusts out its tail and swivels its body under the branch to a position where it cannot be seen.
The terratail, Ophiocaudatus insulatus, is a timid, squirrel-like murine murid and one of the few mammals living on the Pacaus island chain.
The Pacauan whistlers' wariness of snakes is exploited by the terratail. The markings on its tail mimic to a remarkable degree the markings on the head of the Pacauan bird snake. When threatened by a predatory bird, or indeed by any other predatory creature, the terratail throws its tail into the typical snake-threat posture and utters a realistic hiss. It makes its escape rapidly into the undergrowth while its enemy is still recovering from the shock.
The terratail gains protection from the strong resemblance that the tip of its tail bears to the head of a bird snake.