The Mexican Tree Frog is among Costa Rica’s biggest frogs. It is somewhat similar in appearance to the Masked Tree Frog, however the Mexican is bigger; its overall color is brown instead of green, and does not show such a definite dark brown patch behind the eye. The eyes are very similar between both species. It does occur in the Guanacaste province, from which the Masked is absent, however it is not found on the Pacific south from the Tarcoles river. They are nocturnal and arboreal like most tree frogs.
There are three Long-snouted Tree Frog species in Costa Rica, with the Boulenger’s and Olive being both widespread and common accross wet lowlands in the country, and the Dry Forest species being common in the northwestern region (Guanacaste). The Boulenger’s is mostly light brown, including the iris, with small patches of green and darker brown that provides better camouflage. It is colloquially known as “Rana Lagarto” (crocodile frog) in Costa Rica due to its unusually long snout.
It is arboreal and nocturnal, and males frequently call with their body upside-down during the wet season. To help hold this position, the innermost finger can be rotated up to 90 degrees, essentially pointing upwards, which provides a better grip on smooth surfaces like tree branches and trunks. The skin is granular, which might put off some people that feel that its appearance is gross. Yet amphibians have a very important role in wet ecosystems, as some of the insect prey they consume might develop into plagues if unchecked. Most amphibian species have been battling with declining populations, and protecting them from extinction is one of our biggest challenges.
The Cross-banded or Tawny Tree Frog is a drab frog with tan to light brown coloration, expanded disks on toes and fingers, and minimal webbing in the feet. They look very similar to the Masked Tree Frog, which is another species in the Smilisca genus. In Costa Rica, it is mainly found in the Caribbean lowlands. It has nocturnal habits and prefers to be on trees, however during the reproductive season, the males descend to the ground and emit their call from the edge of small ponds. Unlike other nocturnal species that I have photographed, this frog would never fully open the eyes. Its position suggests how sleepy they are during the day. They probably rely on camouflage rather than detecting predators and escaping from them.
The Chiriqui Robber Frog is a rare nocturnal, arboreal inhabitant of humid lowland and montane forests in tropical countries, namely Costa Rica, Panama and Colombia. Their color and pattern is highly variable and cryptic, but overall includes varying shades and patterns of dark colors like brown and black, which helps them to camouflage easily in the forest. It lacks webbing on the hands and feet, but shows greatly enlarged disks on the toes and fingers. The best field mark to identify this species is the black reticulum on the brown eye.
This small bird inhabits the highlands in Costa Rica. Its plumage is drab like most of the birds in its family, but its song is melodious, flute-like with a metallic quality. The belly and face are gray, with the upperparts being brown. While this colors are very similar to other birds in its family, it is identified by the black bill and the brown collar around the throat that separates the face from the belly. It perches in the understory of oak forest and can be found also hoping on the ground or through trails, in places where light is scarce. With enough patience, they will perch at eye level and remain motionless long enough for a good picture.