The Common Ground-Dove is very similar to related species Ruddy and Plain-breasted Ground-Doves, however the Common is lighter in coloration, with a pink bill that is diagnostic; it also shows a scaled pattern in the throat and neck, which is missing from the other ground doves. Also similar to these species is the Inca Dove, which even behaves similarly as it forages most of the time on the ground, however the scaled appearance in the whole body should preclude any confusion. The male is ligher than the female, which looks grayish. All ground doves feature dark spots in the tips of primaries and secondaries, which look like a curved line when the wings are closed, although the Common’s should area spots are more numerous and do not form a line.
There are six species of Antshrikes that occur in Costa Rica, some more elusive than others, but all having a common theme: Their songs is heard more often than they are seen. All of them sing using a pattern of repeating notes that build more speed slowly, abruptly ending in a single note that usually is different from all others. The song of the Black-crowned Antshrike is very similar in pitch to the Barred Antshrike’s, so it is easy to confuse them. The Black-crowned is bigger and does not have the bold markings that the Barred has, only displaying small white dots and stripes on the wings, along a black crown which is difficult to see, given that they are usually perched higher than eye level inside the dark forest.
The Heliomaster genus contains four species, two of which occur in Costa Rica, including the Long-billed Starthroat that can be spotted in the Caribbean and northern lowlands, as well as in the south Pacific. It also includes the Plain-capped Starthroat, which is mostly seen in the north Pacific, central valley and some valleys in the south Pacific.
Both Starthroats have longer than average bills which are straight, although both species have similar bills. The main difference between the Long-billed and Plain-capped is that the former displays a colorful blue-green forecrown, while the latter lacks that crown. To aid in identification, it can be noted that the Long-billed has a postocular spot, while the Plain-capped has a postocular strip. Other than those two specific traits, the two species are very similar, with olive upperparts and gray to white underparts, and a magenta throat that is iridescent. The tips of the tail feathers are white, which can be seen the most dramatically during flight.
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-and-yellow Silky-flycatcher is one of the four species in a unique family around the world, with the Long-tailed Silky-flycatcher being the only other species to be seen in Costa Rica. The male shows a combination of yellow rump, chest and undersides, with gray belly and vent; its throat and head it black, as well as it tail and wings. The Female has a gray throat with a black cap, olive chest, wings and tail. Their shape is similar to other Costa Rica thrushes, as they look rather plump when compared with the Long-tailed. Although Flycatchers by name, they prefer to eat fruits, specializing in berries that are abundant in the highlands; indeed their range is restricted to Guanacaste, Tilaran, Central and Talamanca Cordilleras. They are endemic to Costa Rica and western Panama, thanks to the fact that the Talamanca Cordillera stretches out into Panama.
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 Smooth-head Helmeted Basilisk is a small lizard, measuring up to 11 centimeters in length, where most of this length is represented by its tail. It has the ability to change its skin color, ranging from green through brown and even black. Their skin is most normally patterned, with streaks of dark color breaking the light green overall coloration. Males have big crests on the head, while females do not posses them. Their fingers and toes are elongated. They inhabit tropical rain forests in the lowlands of Costa Rica, both in the Pacific and Caribbean sides of the country.
Caimans are easy to confuse with crocodiles, however both belong to different families in the Taxonomic hierarchy. While each species in both families has its specific characteristics, there are a few physical traits that differentiate species from each family:
- Jaws: The Crocodile has a V-shape, while the Caiman and Alligator have a U-shape. This can be seen most notably from above or the front, not so easily from the side.
- Teeth: In Caimans, due to the way the teeth are placed, the lower jaw’s teeth are not visible when the mouth is closed. Crocodiles do show both upper and lower teeth at all times.
The Spectacled Caiman in particular has become established and common in Costa Rica. Like most reptiles, being cold blooded, they bask in the sun during the morning to warm up their bodies, before going for a day’s hunt. During that time, they may lie motionless in almost any place, like fallen trees, beaches and riversides. Adults have a length between 1.4 and 2.5 meters.
The Plumed Basilisk, also known as the Jesus Christ Basilisk due to its incredible feat to run on water, is one of the four species of the Basiliscus genus and of three species to occur in Costa Rica. The similar Common Basilisk is brown with two yellow lines that run one through they, and a thicker one from below the eye, both ending in the upper portions of the back. The Plumed Basilisk is green, and the male has a big crest that protudes both on the head, back and tail. Most of its body is green with light blue spots around the back, a color pattern that lets it camouflage very easily in foliage and vegetation, particularly during the morning when they bask in the sun to warm up their bodies. Both their fingers and toes are very large, with scales that can be extended, increasing the effective surface area of their feet and enabling them to run over water for short distances, up to 20 meters.
The Common Basilisk, also known as the Jesus Christ Basilisk due to its incredible feat to run on water, is one of the four species of the Basiliscus genus and of three species to occur in Costa Rica. The similar Plumed Basilisk is green, and the male has a big crest that protudes both on the head, back and tail, while the Common Basilisk only has a crest on the head and a small ridge on the back. It is brown with two yellow lines that run one through the eye, and a thicker one from below the eye, both ending in the upper portions of the back; this color pattern lets it camouflage very easily, particularly during the morning when they bask in the sun to warm up their bodies. Both their fingers and toes are very large, with scales that can be extended, increasing the effective surface area of their feet and enabling them to run over water for short distances, up to 20 meters.