habu

Habu is a common name for venomous pit vipers native to the Ryukyu Islands of Japan, most notably the Okinawa habu, Protobothrops flavoviridis (formerly Trimeresurus flavoviridis). The term can refer to several related snakes in the region and is widely used in local languages and literature.

Description and identification: Habus are relatively large for venomous snakes, typically reaching about 1 to 1.5 meters in length. They show a range of colors from greenish to brown, often with a darker dorsal pattern or crossbands. Juveniles may display more pronounced markings. Like other pit vipers, they have heat-sensing pits between the eyes and nostrils.

Distribution and habitat: The Okinawa habu is found on Okinawa and other Ryukyu Islands, inhabiting forests, grasslands, and edges near human settlements. They prefer sheltered microhabitats such as leaf litter, logs, and rock piles and may bask in sun in open areas.

Behavior and diet: Habus are ambush predators feeding on small mammals, birds, lizards, and frogs. They are generally nocturnal or crepuscular, though activity can occur during the day in warm weather. They will strike in defense if startled or cornered and tend to retreat to cover afterward.

Venom and medical significance: The venom can cause severe local tissue damage, swelling, pain, and may produce systemic effects such as nausea, coagulation abnormalities, or shock. Bites require prompt medical attention; antivenom specific to habu venom is used for treatment. First aid emphasizes immobilization, keeping the limb still and at or below heart level, avoiding incisions, suction, or tourniquets, and seeking professional care.

Taxonomy note: In older literature the species is listed as Trimeresurus flavoviridis; current classifications commonly place it in Protobothrops flavoviridis.