Green-winged Macaw parrot bird head.

They are also called Red-and-Green Macaw.

This is one of two Macaw parrot birds that can fly free and are trained to come back to their owner at a voice signal. The birds owner often let them fly around Dolores Park in the afternoon, when it's not too windy. It's amazing to see those beautiful rainbow-colored pet birds fly around and come back to land on their master's shoulder.

For more information about Green-winged Macaw birds, read en.wikipedia.org/wiki/Red-and-green_macaw.

Photo taken in Dolores Park (San Francisco)