No. 0526 / 1 402

Black-tailed rattlesnake

Crotalus molossus

お医者さんが必要命にかかわることはまれだけど、かまれたらお医者さんへ。

かむ食べもの：肉

The black-tailed rattlesnake is a venomous pit viper that lives in the south-west of the United States and in Mexico. It is known as one of the calmest rattlesnakes, and it relies on camouflage rather than confrontation.1

すんでいる場所

South-western United States (Arizona, New Mexico, west and central Texas) and Mexico south to Oaxaca, plus some Gulf of California islands1

北アメリカ

ホーム

It lives in grasslands, desert areas, and rocky and mountainous areas, as well as high-altitude forests. It has been recorded at elevations up to 2930 m. It is a primarily ground-dwelling species, but it is an able climber and an expert swimmer.1

長さ

76 cmから1.1 m (2.5 ftから3.5 ft)1

最高速度

時速約3.6 km（時速2.2マイル）

陸で, おおまかな予想

何を食べるの？

Its main food sources are rodents, other small mammals, birds, and small reptiles such as small lizards.1

Black-tailed rattlesnakeの写真 — Black-tailed rattlesnake。写真：Caudatejake。 CC BY-SA 4.0, Wikimedia Commons.

見分け方

Body colour ranges from yellows and olive greens to browns and black.1
The tail scales are entirely black, which gives the species its name.1
Often has a black band that runs across the eyes and down to the corners of the mouth, forming a facial 'mask'.1
Has a rattle made of keratin at the end of the tail.1

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？

Its venom is primarily hemotoxic, meaning it mainly acts on the blood and surrounding tissue, as with most crotalids (pit vipers). It is only about two-thirds as toxic as western diamondback venom. Because the venom is weaker, the snake has larger venom glands than most rattlesnakes in its region and injects large quantities into prey.1

人にとってどれくらい危険？

人への危険: 深刻かまれたらお医者さんへ。死ぬことはとてもまれだよ。

Bites are fairly rare, because the snake is considered one of the most docile rattlesnakes. The venom is generally not fatal to humans.1

いい知らせ：お医者さんには、これに効く薬（抗毒素）か治療法があるよ。1

こわいとき、どうするの？

It normally tries to slither away when confronted, but it will rattle when cornered, and it relies mostly on camouflage to avoid discovery.1

かまれたら

CroFab antivenom is often used to treat bites from this snake.1
その人をじっとさせて落ちつかせ、かまれた手足を心臓と同じ高さにして、指輪やきついものをはずし、急いで病院へ。

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2匹を鼻からしっぽまでならべた長さバナナ6本をたてにならべた長さ100 mを100秒で走れる（いちばん速い人間は9.6秒）

Black-tailed rattlesnake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？

リクガメ 時速約0.3 km (0.19 mph)

Black-tailed rattlesnake 時速約3.6 km (2.2 mph)

歩いている人 時速約5 km (3.1 mph)

知っておく価値あり

データ

Its venom glands are larger than those of most rattlesnakes in its region, which compensates for its weaker venom.1

It is considered one of the most docile rattlesnakes because of its calm demeanour and curious nature.1

In the spring and fall it is mainly active during the day, but in summer it becomes nocturnal to avoid the heat.1

In winter it hibernates in dens made and abandoned by other animals, often sharing them with other snake species.1

Its lifespan averages 15 to 20 years.1

うそ・ほんとう

うそ： The number of segments in a rattle shows how old a rattlesnake is.

ほんとう： Each time the snake sheds its skin, a new segment is added. Snakes can shed several times a year, and the rattle is fragile and can break, so its length is not an accurate guide to age unless the tip (terminal button) is intact.1

毒のエキスパート向け

学名: Crotalus molossus
グループ: ガラガラヘビ
家族: Viperidae2
ならびかえ: Squamata
大陸: 北アメリカ
赤ちゃん: The female gives birth to live young in the summer. Litters can have as many as 10 to 12 young but usually average four to six.1
野生でのようす: Least Concern1
人への危険: 3 / 5: 深刻3