Purple Gallinules are some of the most brightly colored birds that you can see walking in Costa Rica. Indeed while they can also fly, they more commonly wade in shallow waters and in dense grass plains, looking for prey. I have seen them in Palo Verde in big numbers, and spotted individuals in Rio Frio, where they join chickens and forage in the backyards of houses; indeed I was able to see two adults rearing four young hatchlings, which were still covered in black fluffy hairs, getting along with the chickens just fine. The underside and head is entirely purple with a metallic look, showing a small light blue patch on the forehead. The beak is mostly bright red, with a yellow tip. The upperparts show blue to olive green hues, particularly on the wings. The yellow legs are long, letting them to wade in shallow edges of lagoons without having to swim.
The Black-headed Saltator has a grey belly, black and whitish throat, white supercilliary and olive upperparts. It can be confused with the smaller Buff-throated Saltator however the Black-headed does have a black nape and white throat, which is very distinctive, and their songs are different. This species is very wary of humans, and although they approach fruit feeders, they make it hesitantly. At the first sign of human presence, they will fly away.
The Large-footed Finch is large in comparison with most other species in the finch family. They prefer to stay on the ground, and at first might resemble small chickens due to their common behavior of scratching the leaf litter for food with their legs. Their overall color is olive, with a gray head and black face; also note the black strips running from the face to the back of the neck. Their main habitat is the highlands at Central (Volcan Barva, Cerro Buenavista) and Talamanca cordilleras. It delivers a song at intervals, composed of high-pitched whistles.
The Olive-backed Euphonia is very peculiar among the family of euphonias. Most euphonias are blue and yellow, but the Olive-backed has green and brown tones in the underparts, with olive in the back and a small yellow patch on the nape. In a lucky sight, I witnessed a parent feeding small pieces of banana to a juvenile, which agitates the wings very fast to get some food. Interestingly, the juvenile was near banana in the feeders, but instead of grabbing their own pieces, it preferred the pieces that the parent was giving him / her.
This sparrow has a very peculiar song. It starts with a pair of very high and a lower note, just about a second apart, and the pair is repeated a few times. Then it starts to do a third note, and repeats it many times, in an accelerating fashion, until it stops and becomes silent. Then the song starts again. It is found in the Caribbean lowlands of Costa Rica, in areas of dense vegetation cover. Its underparts are gray, while the upperparts are olive in color. It has two black stripes on its head, one on each side, separated by a gray stripe on the center. It also has a black line that passes through the eyes and almost reaches the neck.
The Hoffman’s Woodpecker is a pretty common sight in Ciudad Colón where I lived before, not so common in Rio Frio where my parents live, but they still approach the fruit feeders from time to time. Their underparts are gray olive, while the upperparts are barred in black and white. The nape is yellowish, while the male has a red cap. Their call is high pitched and can be heard from quite far away. Like most woodpeckers, they frequently perch on branches looking upright or upside down, traversing the branch looking for insects.