Nile crocodile - Nile crocodile

A crocodile of the family Crocodylidae, order Crocodilia, class Reptilia. Also known as the African crocodile. Found in most of Africa except the northwestern part, and on the island of Madagascar. It is one of the largest living crocodile species, reaching a total length of 4 to 6 meters, and a maximum of 7 meters. It inhabits freshwater rivers and lakes, including the Nile and Congo, and some reach brackish waters and coasts. It lives in groups, sunbathing on the shore during the day. At night, it enters the water and attacks and drowns mammals such as antelopes that come to the shore to drink, but sometimes multiple crocodiles cooperate and rotate in opposite directions to bite off their prey. It also catches water birds and fish, and young ones feed on frogs, crustaceans, and insects. Females build nests on the shore with sand and dead branches, lay about 16 to 80 eggs, and guard them nearby, but they are sometimes stolen by monitor lizards and other animals. The mother crocodile helps the baby crocodiles hatch, carrying them in her mouth and moving them to safety in the water. Although they are dangerous to humans, in some areas they are protected as objects of worship. In ancient Egypt, they were considered messengers of the sacred gods.

[Takahiro Matsui]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

爬虫(はちゅう)綱ワニ目クロコダイル科のワニ。別名アフリカワニ。北西部を除くアフリカの大部分およびマダガスカル島に分布。全長4～6メートル、最大7メートルに達し、現生ワニ類では最大種の一つ。ナイル川、コンゴ川をはじめ淡水の河川や湖沼に生息し、一部は汽水域や海岸にも及んでいる。集団で生活し、昼間は岸辺で日光浴をする。夜、水に入り、岸辺に水を飲みにくるカモシカなどの哺乳(ほにゅう)類を襲って水死させるが、複数が協力し互いに逆方向に回転して獲物をかみ切ることもある。そのほか水鳥や魚などをとらえ、幼体ではカエル、甲殻類、昆虫などを餌(えさ)とする。雌は岸辺に砂や枯れ枝で巣をつくり16～80個ほどを産卵し、傍らで守るが、オオトカゲなどに盗まれることもある。母ワニは子ワニの孵化(ふか)を助け、口で運んで安全な水中に移す。人間にも危険であるが、地域によっては信仰対象として保護している。古代エジプトでは聖なる神の使者とされていた。

［松井孝爾］

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