Green Violet-ear (Colibri thalassinus) hummingbirds are common to locally abundant residents in the middle and higher elevation mountains of Costa Rica, mainly in the more open areas of the forest where there are plenty of flowering plants. These glittering, jewel-like hummingbirds are found in the mountains of central Mexico down to western Panama in Central America and in the Andes mountains of South America. Green Violet-ears are also accidental visitors to the United States and Canada.

In May of 2007, I observed these and many other Green Violet-ear hummingbirds at about 7000 feet (2134 m) in elevation at the Savegre Mountain Hotel in San Gerardo de Dota, Costa Rica. The numerous Green Violet-ears and swarms of other hummingbirds there are attracted by the hotel's lovely flower gardens and plentiful hummingbird feeders. Every hummingbird feeder had several Green Violet-ears visiting it, and these glittering green hummingbirds were easy to spot amidst the hummingbird swarm because of their remarkably bright, all-over iridescence.

Green Violet-ear hummingbirds have a somewhat decurved, black bill and are a bright iridescent green color with a distinctive blue to violet ear patch behind their dark eyes, a blue-tinged breast patch, and a dark band across their tail. The females and especially the immatures have less glitter to their plumage.

Because of their iridescent feathers, the color of Green Violet-ears can vary greatly depending on the light and angle of view, from a dull greenish gray in dim light to a brilliant emerald green, metallic blue-green, or dazzling golden green in bright light.