Some of the common mammals include the coati (pizote), a dusk and dawn hunter related to the raccoon (mapache). The collared peccary (saíno) resembles a pig and lives in large groups in the forest. The rodentlike agouti (guatusa) can be found foraging on the forest floor near rivers and streams.

Tapirs (macho de monte), huge 250-kilo (550-lb) mammals, are endangered, partly because they’re prized as delicacies on the dining table, and partly because of shrinking habitat. The vampire bat (vampiro) attacks cattle in the northwest, but are only one of over 100 species of bats in Costa Rica.

Famous frogs are, of course, the golden toad (sapo dorado), now feared to be extinct, the red-eyed tree frog and the poison dart frog (dendrobates pumilio). The latter is a tiny frog that advertises its toxicity with its bright color. They are less than an inch long and can be found under low plant leaves.

The leathery-scaled, olive-gray crocodile (crocodilo) has beady eyes that stare blankly from its head as it skims the surface of the water hunting for frogs, fish, birds and small mammals. They and their slightly smaller cousin, the dark brown caiman, hunt mainly at night. During the day they sun themselves along the banks of rivers and mangrove swamps.

But it’s the snake (serpiente) that most people worry about when trekking around the forest. And Costa Rica has 162 species. But take heart, only 22 are poisonous. So, it’s a mixed blessing if you encounter one. The chances are that you’ll be with a naturalist guide, who generally carries anti-venom as a precaution. Snake-bitten tourists are very rare.We have only seen one snake in the wild, a small but venomous yellow eyelash viper, sunning itself in the crook of a tree when we were safely riding an aerial tram.

Snakes generally slip away when humans approach, but the one that is responsible for the most bites is the aggressive fer-de-lance (known by its Spanish name, terciopelo) It has an olive-brown to dark-brown skin with light color “X” markings along its back and sides. If you encounter one, stand very still until it calms down, then try to get back out of range. If you do get bitten, seek help immediately. The fer-de-lance sometimes strikes first and asks questions later. The king of snakes is the boa constrictor, which kills its prey by crushing it in a tight coil. When you’re hiking, stay on the trail.

You can admire these snakes safely in the serpentarias in San José, Grecia, or Parque Viborana near Turrialba.