Costa Rica overview

Rainforest amphibians generally have toxins in their skin. The mildest poisons just taste bad, while the strongest can kill predators (including humans) by causing vasoconstrictio, respiratory paralysis, hypertension, and other mortal conditions. The toxin may be ingested through the mucus membranes of the mouth or throat, or through the pores in the skin. The message: don’t touch these guys. (Ironically, they may be the source of lifesaving antibacterial and antiviral compounds that scientists are still researching). Big bullfrogs that are common near beaches can even shoot toxin a distance of up to six and one half feet, so be wary of them, too.

So named because indigenous warriors poisioned their arrow tips with its venom, the vermillion-colored poison dart frog spends its entire life high above the rainforest floor. Bromeliad water vessels serve as the frog’s breeding grounds, protecting the developing tadpoles from predators. At the end of the two month gestation period, an adult dart frog emerges from the plant shelter with a fully developed defense system: Its skin glands exude a poison that rools off its back like drops of sweat. Any animal taking a poison dart frog into its mouth is poisoned. The frog’s brilliant red color serves as a warning.

Other toxic amphibians warn predators with “flash colors” – brightly colored leg or groin areas, which are revealed on when the animal jumps. This startles the predator, and might dissuade it from attacking.
Three kinds of sea turtles nest on Costa Rica’s shores: the pacific or olive ridley at playa Nancite in Santa Rosa National Park and at Ostional near playa Nosara; the green turtle at Tortuguero; and the leatherback at Playa Grande near Tamarindo, Tortuguero, the Pacuare Reserve near Parismina, and the Gandoca – Manzanillo Wildlife Refugee in Talamanca.

Two kinds of crocodiles are found in Costa Rica. The smaller ones, called caymans, which grow no longer than three feet, live in creeks, ponds, mangrove swamps, and beach lowlands. They are most common in the Corcovado area. What are commonly called crocodiles are the larger animals, reaching up to 13 feet in length. We have seen them lounginh in the muddy banks of rivers in the Northern Zone, on the boat trip to Tortuguero, on the Rio Sierpe, and at the Carara Biological Reserve near Playa Jaco.