Why Crocodiles Are Absent from the Mississippi River

American crocodiles (the only crocodilian native to the U.S.) are not found in the Mississippi River.

Habitat Preferences

• Primarily inhabit saltwater and brackish environments – mangrove swamps, coastal lagoons.
• Can tolerate freshwater but require consistently warm temperatures.

Why the Mississippi Is Unsuitable

The Mississippi River experiences cold winter temperatures that fall well below the thermal tolerance of crocodiles. They cannot survive the seasonal cooling, so their U.S. range is limited to southern Florida and the coastal Gulf regions.