Birds panting to cool down

Glosy Starling

Yellow-vented Bulbul

Brown Shrike

(From AI Overview)

 Birds pant, or more specifically engage in "gular fluttering," to cool down by rapidly breathing and vibrating moist throat membranes, which facilitates evaporation and heat dissipation. 

Here's a more detailed explanation

Lack of Sweat Glands:

Unlike mammals, birds lack sweat glands, so they rely on other methods to regulate their body temperature, like panting. 

vaporative Cooling:

As air rushes in and out of the bird's respiratory system, moisture in the lungs, throat, and mouth evaporates, absorbing heat and cooling the bird. 

Other Cooling Methods:

Birds also seek shade, bathe in water, and lift their feathers to allow air to circulate and help cool their bodies.