The Buff-rumped Warbler is a small, loud bird of the Caribbean and Pacific lowlands, usually found in close proximity to water streams and rivers, much like the Torrent Tyrannulet does in higher elevations. The places it inhabits are dark, hence it is difficult to see; look for two essential clues: 1) An accelerating high pitched song that seems to come from a water source and 2) a small white patch that swings from one side to the other close to the ground, which is caused by the bird’s habit to swing its tail in such a fashion. It can also be spotted as it flies away rapidly when people approach them.
The Grayish Saltator belongs to the same family as the Black-headed Saltator, which at my parent’s home in Río Frío is much more common. As it name implies, its upperparts are gray, but the underparts are brownish, particularly close to the vent. The throat has a central white stripe, bordered by two black strips. It also shows a white supercilliary which ends right after the eye. The beak is strong as other Saltators. They sometimes come to fruit feeders, but are more wary that most other birds.
Green Iguanas are the biggest species of lizards in the world, reaching lengths up to 1.5 meters including the tail. They are abundant in Costa Rican lowlands, and can be found in most of America’s continent, either naturally occurring or as established populations of escaped pets, as they are a very frequent target among pet lovers. They can be found in many beaches, around rivers, high in the tree canopy or walking slowly on the grass. Their diet is composed mostly of leaves, flowers and fruits, although some individuals have been observed eating insects and rodents.
Green Iguanas are not necessarily green in color, instead they have a lot of variability in their range. In some areas they are green, others brown or red, even blue in Peru. The back of the male is covered with spines, a defense mechanism to keep predators at bay, and they feature a dewlap, which is a fold of skin that starts at the front of the lower jaw and ends at the junction where the front limbs start. The dewlap is normally hanging, although it can be displayed as a sign of aggression.
The Nicaraguan Seed-Finch is one of Costa Rica’s biggest finches species, only surpassed by the Wedge-tailed Grass-Finch, which is even rarer and has a longer tail. It looks similar to the Thick-billed Seed-Finch, with the male being uniformly black and the female uniformly brown, albeit with a bigger size. Their bills are undoubtely specialized for breaking down seeds and the male’s bill is particularly conspicuous, given its pink coloration. In Costa Rica, it can be found in lowland areas of the northern area, near the border with Nicaragua, and in a thin strip along the eastern coast of the Caribbean.
The Northern Waterthrush is a member of the Warbler family with a body plan more similar to that of a thrush, albeit smaller. It is brown in the upperside, with brown streaks on a white belly. It has a white superciliary and flecking on the throat. The very similar Louisiana Waterthrush has a wider superciliary, with a white throat. Both species are terrestrial, with the Northern preferring slower moving streams and edges of ponds. Both species teeter their body as they move around. They are both migrants that occur in Costa Rica mainly from mid August to mid May, with the Northern being the most widespread and commonly seen in the territory.
The Barred Antshrike is a beautiful bird. The male for one part is entirely barred, with white and black lines covering the whole body. The female is not barred, but the brown coloration is pretty in itself, with a tuft that looks the most elegant. I have seen them in Rio Frio and also in El Rodeo, near Ciudad Colón. Their song is also very intriguing, with a series of accelerating, high-pitched chirps that then end abruptly on a harsher note. While they sing, they also incline their bodies up and down, presumably on a display to show ownership of their territory.
The Yellow-faced Grassquit is a seedeater found on grasslands. I have seen this species a few times at Fincas Bambuzal, Rio Frio where my parents live. The yellow face is diagnostic when trying to identify versus other seedeaters that may inhabit the same zone. They like to perch both on grass branches and in fence wires at the edge of trails and gravel roads; they will usually share space with Variable Seedeaters and Thick-billed Seed-Finches, although they are not confused easily with those species. Small juveniles take the risk to abandon the nest and call for their parents to feed them. It is very difficult to locate them in the tall grass.
This is a very small and nervous bird. Taking a close up picture of this bird proved to be difficult, even during sunny days with great light available. The male in low light it looks black, but in sunlight it glows in a metallic blue color. The female is rather drab, sporting a brown look. The male perches in fence wire and posts, then suddenly starts jumping while making its call, doing acrobatic maneuvers in mid air, all to attract nearby females.