Mississippi alligator

A crocodile of the Alligatoridae family, order Crocodilia, class Reptilia. It is found in the lower Mississippi River basin, the Gulf of Mexico coast, and the Florida Peninsula in the United States, south of 35 degrees north latitude. It is the largest species of the Alligatoridae family, reaching a total length of 2 to 3 meters and a maximum of 5.7 meters, but large individuals are not seen very often these days. It has a flat, wide snout with a rounded tip. It lives in freshwater rivers and lakes, and its hind legs are well-developed and good swimmers. It is docile in nature, and feeds on small mammals, waterfowl, fish, frogs, snakes, etc., and its young mainly eat crustaceans such as crayfish and aquatic insects. In early summer, females build nests of mud, plants, and dead branches near the water, lay about 15 to 80 eggs, and protect them. The female parents spend the next spring with the baby crocodiles and take care of them.

[Takahiro Matsui]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

爬虫(はちゅう)綱ワニ目アリゲーター科のワニ。アメリカ合衆国の北緯35度以南のミシシッピ川下流域、メキシコ湾沿岸地方、フロリダ半島に分布する。全長2～3メートル、最大5.7メートルに達するアリゲーター科の最大種であるが、現在では大形個体はあまりみられない。吻(ふん)部が扁平(へんぺい)で幅広く、吻端は丸みを帯びる。河川、湖沼の淡水に生息し、後肢には水かきが発達して遊泳が巧みである。性質はおとなしく、餌(えさ)は小哺乳(ほにゅう)類、水鳥、魚、カエル、ヘビなどで、幼体ではザリガニなどの甲殻類、水生昆虫が主食である。雌は初夏になると水辺に泥と植物や枯れ枝で巣をつくり、15～80個ほどを産卵し、これを守る。さらに雌親は翌春まで子ワニと過ごし世話をする。

［松井孝爾］

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