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American Alligator

Alligator mississippiensis

A big, armored reptile of the southeastern U.S. swamps and rivers that can go through 3,000 teeth in its life.

🐊 Crocodilians
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About the American Alligator

American alligators live from North Carolina to central Texas in slow rivers, swamps, marshes and lakes. Females average about 8 feet long and males about 11 feet, and big males can weigh nearly 1,000 pounds. Bony plates in the skin act like armor, and nostrils on top of the snout let them breathe while mostly underwater. They eat fish, snails, birds, frogs and mammals.[1]

Quick facts

Scientific name
Alligator mississippiensis[2]
Size
Females average 8.2 feet; males average 11.2 feet.[1]
Weight
Big males can weigh nearly 1,000 pounds.[1]
Lifespan
About 50 years in the wild.[1]
Diet
Carnivore. Fish, snails, birds, frogs and mammals.[1]
Habitat
Slow freshwater rivers, swamps, marshes and lakes.[1]
Where it lives
Southeastern United States, from North Carolina to central Texas.[1]
Babies
35 to 50 eggs in a mound nest; hatch after about 65 days.[1]
Conservation status
Least Concern (IUCN Red List, assessed 2018).[2]

Fun facts

  • An alligator can go through 3,000 teeth in its lifetime.[1]
  • Nest temperature decides whether baby alligators are male or female.[1]
  • Alligator jaws can crack a turtle shell.[1]

Vocabulary

crocodilian
A member of the reptile group that includes crocodiles, alligators and caimans.
osteoderm
A small bony plate inside the skin.
swamp
Wet, spongy land often partly covered by water.
incubation
Keeping eggs warm until they hatch.
least concern
A conservation label meaning a species is widespread and not at risk of dying out soon.

See it in person

Sources

  1. [1] Smithsonian's National Zoo & Conservation Biology Institute. “American alligator.” https://nationalzoo.si.edu/animals/american-alligator (accessed 2026-10-02)
  2. [2] IUCN Red List of Threatened Species. “Alligator mississippiensis (American Alligator).” https://www.iucnredlist.org/species/46583/3009637 (accessed 2026-10-02)

Facts last checked 2026-10-02.

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