No. 0572 / 1 402

Brown tree snake

Boiga irregularis

名前について： Its genus, Boiga, is a group of about twenty-five snakes called 'cat-eyed' snakes because they have vertical pupils.1

痛いだけ痛いけど、大きな害はないよ。

後ろに牙のあるヘビ

かむ食べもの：肉

人への危険: 痛いすごく痛いこともあるけど、深刻になることはほとんどないよ。

The brown tree snake is a slender, night-active snake that climbs well and hunts in trees and on the ground. It lives in coastal northern and eastern Australia, eastern Indonesia, Papua New Guinea and nearby islands. It is famous for harming wildlife on the island of Guam, where it was introduced by accident.1

すんでいる場所

Coastal eastern and northern Australia, eastern Indonesia, Papua New Guinea and islands of northwestern Melanesia. Introduced to Guam.1

アジア, オーストラリアとオセアニア

ホーム

It lives in forests, grasslands and sparsely forested areas, and is common in places disturbed by people. It hides during the day in palm crowns, hollow logs, rock crevices, caves and the dark corners of thatched houses near the roof. In Darwin, Australia, it is most often met in suburban areas during the wet season from January to March.1

長さ

1 mから2 m (3.3 ftから6.6 ft)1

最高速度

時速約6 km（時速3.7マイル）

陸で, おおまかな予想

何を食べるの？

It eats birds, lizards, bats, mice, other small rodents and frogs, as well as many invertebrates and their eggs. It hunts using both sight and chemical cues. Often it wraps its body around its prey like a constrictor to hold it still while it eats.1

Brown tree snakeの写真 — Brown tree snake。写真：Pavel Kirillov from St.Petersburg, Russia。 CC BY-SA 2.0, Wikimedia Commons.

見分け方

Slender body, with a large head compared to its body1
Usually brown, but can be yellowish, green or beige1
Some individuals have red, saddle-shaped blotches1
Vertical pupils, like a cat's eyes1
Active at night, and usually found in trees1

毒パワー

かむ

かむときに、毒が牙や歯から出るよ。

その毒（かむ・刺す毒）はどうなるの？

It has two small, grooved fangs at the back of the mouth, so venom flows into the bite slowly rather than being injected in one go. The venom is weakly neurotoxic, meaning it affects the nerves, and may also damage cells locally. Its effects are trivial for adults, and it is mainly used to subdue lizards.1

人にとってどれくらい危険？

人への危険: 痛いすごく痛いこともあるけど、深刻になることはほとんどないよ。

The snake is considered aggressive when threatened but not dangerous to adult humans. Serious medical consequences have been limited to children, who are more affected because of their low body mass. On Guam, it has caused widespread power outages, pet losses and emotional distress to residents.1

こわいとき、どうするの？

When threatened it is highly aggressive, lunging and striking at the attacker repeatedly.1

かまれたら

かまれたところを洗い、その人を落ちつかせて、医療の助けを受けよう。種類によっては（ブームスラングなど）何時間もあとに命にかかわることがあるよ。

まず必ず救急番号（112、000、911）に電話しよう。これは一般的な応急手当の案内で、医療のアドバイスではないよ。応急手当の基本

安全に過ごそう

野生の動物には、小さくても、ねているように見えても、死んでいるように見えても、ぜったいにさわったり、つかまえたり、からかったりしないこと。
近づかないで。出会ったら落ちついて、ゆっくりあとずさりして、そのまま行かせてあげよう。
かまれたら：落ちついて、じっとして、救急番号（112、000、911）に電話するか、急いで病院へ行こう。見た目をおぼえておいてね。写真があると役に立つよ。

きみをねらっているわけじゃないよ。毒はエサをとったり身を守ったりするために使うだけで、本当はかくれていたいんだ。安全に過ごすためにもっと知ろう

世界のどこ？

アフリカアジアヨーロッパ北アメリカ南アメリカオーストラリアとオセアニア

どれくらい大きい？

どれくらい長い？

飼いネコ4匹を鼻からしっぽまでならべた長さバナナ11本をたてにならべた長さ100 mを60秒で走れる（いちばん速い人間は9.6秒）

Brown tree snakeは、きみとくらべてどれくらい大きい？

ブラウザで計算しているだけ。何も保存されないし、どこにも送られないよ。

どれくらい速い？

歩いている人 時速約5 km (3.1 mph)

Brown tree snake 時速約6 km (3.7 mph)

自転車に乗った子ども 時速約12 km (7.5 mph)

知っておく価値あり

データ

Snakes on Guam have been seen moving up large smooth cylinders using a method called 'lasso locomotion', which had not been recorded in snakes before. It is tiring, so they move slowly and stop often.1

On Guam, where prey is plentiful and there are few predators, the snakes have grown to 3 m, much longer than their typical 1 to 2 m in their native range.1

Shortly after World War II, the snake reached Guam by accident, probably as a stowaway in ship cargo or in aircraft landing gear. Its numbers then grew to unprecedented levels.1

Trained dogs are used on Guam to find and remove snakes before cargo and transport vessels leave the island.1

Female brown tree snakes have been seen performing courtship behaviours normally used by males, such as tongue-flicking and head-jerking.1

Brown tree snakes can survive for long periods without food.1

うそ・ほんとう

うそ： The brown tree snake is a deadly snake that is dangerous to adults.

ほんとう： It is not considered dangerous to adult humans. Its venom is weak and serious effects have mainly been seen in young children.1

毒のエキスパート向け

学名: Boiga irregularis
グループ: 後ろに牙のあるヘビ
家族: Colubridae2
ならびかえ: Squamata
大陸: アジア, オーストラリアとオセアニア
赤ちゃん: The female lays 4 to 12 oblong eggs with leathery shells and may lay up to two clutches a year. The eggs hatch about 90 days later.1
人への危険: 2 / 5: 痛い3