What's a tropical dry forest?

           

Before coming to Costa Rica, I imagined it to be a land full of the famous red-eyed tree frogs and the lovable sloths. I imagined trekking through the depths of the jungle with a machete in hand and binoculars in the other. I imagined packing my hiking backpack and going on onerous hikes. In my head, the entire country was essentially one giant rainforest. I knew that the capital, San Jose, was a bustling city, but I assumed that it was completely surrounded by forests.

            I soon found out that I could not have been farther from the truth. In the country the size of South Carolina, there are twelve different life zones according to the Holdridge Life Zones (a system used to classify different regions based on variations in temperature and precipitation) which accounts for numerous ecosystems. Of course Costa Rica has tropical rainforests, but it also has low-, mid-, and high-elevation ecosystems that all have their distinct characteristics. During the OTS course, I was utterly shocked to find out about ecosystems that I did not even know existed. Every year since second grade, there has always been a small section in my science classes dedicated to different ecosystems. I learned about the six typical biomes: rainforests, savannahs, deserts, temperate forests, grasslands, and tundra, but I had never once heard about the tropical dry forest. I thought Costa Rica’s tropical dry forests sounded like a misnomer – how could there be a “dry” ecosystem in an area of the world where rainfall is typically the highest?

            Now, not only have I learned about tropical dry forests, but I have actually seen one in person. This is super exciting for me because they are among the most endangered ecosystems in the world -- less than 1% of it remains and less than 0.1% of it is conserved. The dry forest here at Palo Verde National Park is characterized by its two seasons. We are currently at the end of the rainy season which occurs from late May until late November. The grasses outside are still green, and the trees have all their leaves. In the upcoming weeks, the dry season will start. During this period many of the plants drop their leaves, and everything turns brown. In general, dry forests also tend to have a lower canopy than their tropical rainforests counterparts, and the plants are equipped with an array of spines, thorns, and prickles. Because of the lack of consistent rain, tropical dry forests also do not tend to have as much biodiversity as a tropical rainforest; however, they still have some amazing animals.

            While studying at Palo Verde, there has been a weird disconnect between seeing rabbits and white-tailed deer and hearing the howler monkeys off in the distance. For a split second I think I am back home in Tennessee as I walk around the deciduous tree forests and see the stereotypical forest dwelling creatures, but the reality sets in that I am still in Costa Rica when I look up and see howler monkeys and white faced capuchins resting in the trees, or I see large iguanas on my way to the trails. I walk through the forest that looks similar to home but sounds nothing alike as I listen to the scarlet macaw calling from above.  It never occurred to me that it is possible that all these different animals could live together in unison. As much as I love the wildlife back home, I am going to miss some of the fauna I’ve seen here. 

Kiersten Bell

Duke University