The Great Green Macaw is a pretty uncommon sight in Costa Rica. It is a huge bird, their calls are very loud. I had the opportunity to observe the birds very close in Rio Cuarto, on May 20th, 2017 during a Photography Workshop with To The Wonder. Alvaro Cubero, our wildlife photography guide explained that Green and Scarlet Macaws do not hybridize in the wild, however in this refuge, a pair of Macaws have been interbreeding in the last few years, resulting in hybrids being born.
In Rio Frio, where my parents live, it is common to see a pair of these birds flying overhead most of the times I am there. Either they are more common in the area, or a single pair of birds has taken residence. They are easy to identify, as their harsh call is heard from very far away and no other parrot has such a characteristic call, other than the Scarlet Macaw. They like to feed on almond and are likely to be seen perching relatively high in those trees.