Check! Check! Check!... we can learn a lot about Corcovado National Park!

At OSA WILD we have created a new tool for our clients to learn and remember what we have seen and learned from on our overnight tours.

The idea started when some of our clients gathered together at night at the Sirena station with our local guides to remember all the different animals we have seen during our hikes. Some birdwatchers are very serious about checking their list, so we now can please you all to have the necessary information and start checking! 

I have seen it all; people who forgot their list at the hotel, the ones that soak it when we did the river crossing, and others that are not very interest on it… but we have also the ones that are extremely interested and they take it along every hike to mark down every new thing we can see at Sirena Biological Station.

Corcovado National Park protects about a third of the Osa Peninsula. It is widely considered the crown jewel in the extensive system of national parks and biological reserves spread across the country.

The ecological variety is quite stunning. National Geographic has called it "the most biologically intense place on Earth in terms of biodiversity”. The park conserves the largest primary forest on the American Pacific coastline and one of the few remaining sizable areas of lowland tropical rainforests in the world. 

The abundance in wildlife can in part be explained by the variety of vegetation types, at least 13, including montane forest (more than half the park), cloud forest, jolillo forest (palm swamp), prairie forest, alluvial plains forest, swamp forest, freshwater herbaceous swamp and mangrove, together holding over 800 tree species.

A beautiful Aracari, Fiery-billed, you could get the 
chance to check out of the check list!            

Another reason for the diversity (as with all of Costa Rica) is that it lies on a north-south corridor for flora and fauna; part of the "land bridge" and wildlife corridor that links the large continents of North America and South America.

Corcovado contains 50% of the mammal population that we find in the entire country, and we have more than 450 species of birds. Even though we cannot write it all down in our checklist, I have to say that it is really exciting to see how our clients are eager to find new species to check.

Dart frogs... Jewels of our rainforest

Art by Florencia Lathrop

There is no other thing that excites me the most than to talk about Dart frogs. These jewels from the rainforest are extraordinary amphibians that have diurnal habits and that can be easily seen if you know where to look...

There are 3 main genera in Costa Rica, Dendrobates , Phyllobates and Silverstoneia, the first 2 are the most common to see in the lowland rainforest from the Osa Peninsula. Just very recently the some of genera Dendrobates has changed to Oophaga, so now its Oophaga granulifera and Oophaga pumilio. Frogs of this family differ from all other frogs by having two shieldlike flaps on the top of the fingers and toes, although it is hard to see these without a magnifying glass.

Green and black dart frog (Dendrobates auratus)
Their natural habitat are leaves in the rainforest soil
Art by Florencia Lathrop

Most dendrobatids are easily recognized by their bright coloration, which appears to advertise the presence of skin toxins, although some species, primarily in the genus Silverstoneia are cryptically colored and not poisonous.

This family common name derives from the skin toxins mainly found in the genera Oophaga and Phyllobates. Frogs of the genus Phyllobates have skin toxins that can be particulary strong; the skin of the South American species, Phyllobates terribilis, contains toxin sufficient (batrachotoxin) to kill twenty thousand mice or ten adult humans. This is the strongest animal toxin know to biologist.

Recent studies have revealed that the source of the alkaloids, or chemical compounds, responsible for the toxicity of the skin secretions may be the food the frogs eat. Although many insects ‘species that this frog consumes contain alkaloids, more species of ants contain alkaloids than do any other insect group.

Golfo Dulcean dart frog (Phyllobates vittatus)
This dart frog is endemic to the Osa Peninsula.
Photo: Tzirú Pérez

If you want to observe these gems in the Osa Peninsula, you can book a day tour to Corcovado NationalPark and observe at least 2 of these beautiful creatures. Other places you can visit to observe them are:  La Tarde, ElTigre, Matapalo, Tamandua and other special creeks some of our guides at OSA WILD can help you discover.

Please be conscious about the importance of these frogs to the ecosystem and don’t buy or order them. In Costa Rica these are threatened creatures; deforestation and habitat loss have reduced their populations. Buying wildlife is illegal; we know and you know it is way better to see them in their natural habitat.

Art by Florencia Lathrop

Article by Ifigenia Garita
Photography by Tzirú Pérez
Illustrations by the costarrican artist and designer Florencia Lathrop. You can check more of her art work at www.florencialathrop.com 

In the search for unique wildlife...

And off we went, with so much happiness in our faces to the Proyecto Ecoturistico La Tarde. It was Saturday 1pm and the happiest of all was probably Jessica, our logistic and sales manager who knew she could close the office early; we were heading to see something way better than sitting in the office chair and answering emails. We took the 1pm bus that goes to San Isidro and got off at La Palma, where Berni, La Tarde's owner's brother, picked us up and took us on an 8 km car trip.

Osa Wild Team (left to right: Luis Daniel, Ifi, Jessica, and Veronica) 
enjoying our time together at the rainforest

La Tarde is a hot spot of biodiversity, located in the northern part of the Corcovado National Park. On the way to La Tarde, after driving through the community of La Palma and Guadalupe, you can observe from the highest point the "Laguna de Corcovado", a pristine ecosystem that is surrounded by a special type of palm locally called “yolillo” or Raphia sp.

Walking next to Quebrada La Tarde 

Some members of our team forgot one of the most important things you need to bring when visiting this pristine place: boots, rubber boots. Jessica, Vero and Luisda had all to borrow boots; luckily it seems there were enough for us all. At La Tarde you can observe an outrageous amount of snakes. If you go for a night hike, you can encounter many Fer-de-Lance. Last time I heard they had seen over 12 Fer –de-Lance (Bothrops asper) on a 3 hours night tour!

So our guide, Amador was ready to take us to the spot where a unique and incredible species was seen. It has been 8 years since Eduardo, La Tarde's owner, last saw the Black-Headed Bushmaster. We took some water, binoculars and a spotting scope and started our journey. The hike was great, La Quebrada La Tarde is absolutely beautiful, and it’s like walking in a river and having the tropical rainforest just next to you. Huge trees and stunning sounds accompanied us in this pleasant hike.

Lachesis melanocephala

It took us less than 45 minutes to get to the place where more than 8 other passionate naturalists and herpetologist where waiting for the perfect light to shoot a picture. Among them, my teacher, second father, friend and one of the most important persons for me in our community; Mike Boston an specialist in snakes who has waited for more than 18 years for this particular moment to come. He received us with great enthusiasm and we all stayed for at least one more hour admiring the beauty and talking about its ecology.

The Lachesis melanoceophala is a member of the Viperidae family, one of the most specialized predators among all snakes. Their long, hollowed, retractable fangs stab and inject lethal venom into prey animals, which are usually rodents and marsupials. This is the only viper I know that lays eggs (oviparous), and that is endemic to the southern part of our country.

Can you see the snake here? Terrestrial species of snakes are often found coiled, with their head resting on the top of the coil. The coloration tends to mimic their surroundings, especially when coiled. 

We share our gratitude to Eduardo and his family, who has been taking many naturalist, guides and nature lovers to see this breathtaking reptile and which we know that is taking absolute care of his land and educating more and more people about the ecological importance of extraordinary reptiles such as the Plato Negro.

Sharing experiences with Eduardo from La Tarde

Article by: Ifigenia Garita C.