Why do crocodiles bask in the sun?

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Illustration of an estuarine or saltwater crocodile (Crocodylus porosus) with its mouth open, showing scaly skin and powerful limbs, alongside a scale bar for size reference. — crocodile Estuarine, or saltwater, crocodile (*Crocodylus porosus*), found in brackish waters from Sri Lanka, India, Bangladesh, and Myanmar east to the Solomon Islands and Vanuatu and south to Australia.

Crocodiles bask in the sun primarily because they are cold-blooded (ectothermic) animals. Unlike mammals and birds, they cannot generate their own internal body heat and must rely on external sources to regulate their temperature.123

By basking, crocodiles absorb heat from the sun, which allows them to reach an optimal body temperature necessary for essential biological functions, such as hunting and digestion. This behavioral thermoregulation is an energy-efficient strategy that enables them to maintain their metabolism without the high caloric intake required by warm-blooded animals. Conversely, when they need to cool down, they may move into the shade, enter the water, or hold their jaws open to allow heat to escape through the blood vessels in their mouth.13