The Slaty Spinetail is a commonly heard bird near abandoned lots, where grass and bushes had time to grow. They are more difficult to spot than to hear, in part because they choose to stay low inside the vegetation. The adults are dark gray overall, with orange-brown wing feathers and a head cap of the same color. Their tail is relatively long when compared with other birds that share their habitat, and as the name implies, looks rather untidy, like an old broom that has been used to its life span. The juvenile has similar colors with less saturation and lacks the defined head cap.
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 Gray-headed Chachalaca is a relatively big arboreal bird with mostly a brown body and gray head. Their diet consists mainly of fruits. At my parents´ home, up to ten arrive at the feeders where my parents place the papaya. Due to their size, they throw the papaya to the ground while eating, which does not help the toucans when they arrive. They are very loud, particularly when spooked by predators or humans, although not as loud as Brown Jays. They can be seen gliding from tall trees, one after another in rapid succession, relying on the uplift from air currents to avoid expending energy on batting their wings.
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.
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 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 Green Basilisk is (obviously) green, and the male has a big crest that protudes both on the head, back and tail, while the Striped 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.
Hognosed Pitvipers are dangerous beauties. They can reach a size of 60 centimeters of length, which is rather small. According to the WCH assessment, their venom is not letal, but can cause uncomfortable symptoms including pain and swelling. This species has two morphs, one with deep red-brown skin and another with brown-gray skin, both of which display small black markings from neck to tail. Each morph is found in different areas in Costa Rica, although being the same species, they can probably still mate and produce viable offspring. Species having multiple morphs feature individuals with different appearances (usually different skin color or patterns in amphibians and reptiles), but each individual will normally only express one morph.
The Jumping Pit Viper is another feared venomous snakes that occurs naturally in Costa Rica. They have a skin pattern similar to the Fer-de-lance, hence they might be confused on the field. Since both are dangerous, it is still a safe bet to stay away, whether the individual is one species or the other. The Fer-de-lance can be distinguished by the smaller head and ligher eyes; also the Jumping Pit Viper has solid brown triangles all along the body, while the Fer-de-lance features brown markings that are connected diagonally, but on the inside hey have lighter colors.
In spite of its common name, it is not more common for the Picado’s Jumping Pitviper to jump on top of their prey than any other viper species. Its Spanish common name also refers to a “Eye of Round” beef cut, not exactly helpful if someone shouts “Mano de Piedra!”. Their venom is very strong, so people are very cautious if they handle them.
Fer-de-lances are the most feared snakes in Costa Rica, even if they are not the largest species to be found here. They have grown a reputation out of casual encounters and deadly accidents. Part of the reason is that Fer-de-lances are more frequently found close to human settlements than other vipers, creating more chances to see them close. They normally do not display aggressiveness towards humans, preffering to stay concealed and motionless, however this very behavior make them hard to detect. It is common for people working on the field to tell stories of snakes passing through their legs; if not for that, they would have gone unnoticed. When a human is close, their usual reaction is to leave, but sometimes if they feel threatened, they will launch an attack, with potentially devastating consequences for the victim.
You can tell I kept my distance when photographing this specimen. Special care needs to be taken when handling them, and as long as they don’t feel threaten, there should be no accident. I would never handle one of this on my own. It has an habit for approaching homes, unlike many other venomous snakes that stay away. This increases the potential for accidents with unsuspecting victims, even in residential areas where one would not expect to find a venomous snake otherwise.