The heat and humidity are taking a toll on all of the backyard life. This poor mockingbird was doing it's best to stay cool when the temperature was 105F.
Since birds don't sweat, they pant kind of like dogs to cool off. They can use the moisture evaporation to help regulate their temperature. The down side to this is they can dehydrate quickly. They can also help cool their bodies by cooling their un-feathered legs and feet since the blood vessels are closer to the surface.
Backyard bird baths can literally be life savers to some birds on those really hot days. Drinking, bathing and sometimes just standing in the water are all ways our feathered friends try to cope with the summer heat. Next time you step outside and think to yourself how hot and uncomfortable it is, remember that the birds don't have the luxury of going inside to the enjoy the air conditioning. Consider adding a bird bath of some sort to your yard. Even a small dish of water can make a big difference.