Monday, August 19, 2013

Two Trips to the Rainforest


    Growing up, a summer-time ritual in our family was to visit the zoo. Most of my younger years were spent growing up in the greater Detroit, Michigan area, and the Detroit Zoo was a staple in our summer circuit of activities. While visiting the zoo during the dog days of summer, my favorite exhibit to see, without a doubt, was the Penguin House. These strange little birds had such marvelous personality to us kids, and we spent hours watching them. At first glance they seemed clumsy while waddling around on land…but after a quick slide into the water, my brothers and I were marveled as these birds swam impressively through the aquaria -- such charm! And on hot summer days, perhaps the coolest part about visiting the penguins was that the rooms were cool (literally chilled!). 

    Another typical summer-time activity was to travel to greater Cleveland, Ohio to visit family. However, in the summer of 1995, we caught wind that the Cleveland Metroparks Zoo had opened a new, enormous exhibit, featuring tropical plants and animals from around the world. My bros and I were extremely eager to visit this new ‘Rainforest’ exhibit, so we took a day off from the grandparents, loaded our baby-blue Astrovan full of Capri Suns and sandwiches, and took a day trip into the city, to visit the rainforest. 

Spectacled Caiman (Caiman crocodylus), a Central
 and South American crocodilian. Jason Folt photograph. 
    And the Rainforest was well worth the trip. This expansive new display featured incredible biodiversity from tropical rain forests throughout the world. Our family of five walked slowly walked through the exhibits, marveling at golden marmosets, scarlet macaws, poisonous frogs (‘WHAT?! POISONOUS FROGS?!’ –my eight-year-old self), saltwater crocodiles, and the fan-favorite orangutans.

    All told, the Rainforest exhibit was phenomenal then, and still is today. It tells the tremendous story of tropical biodiversity, of the fascinating plants and animals that make their living in the wet tropical biomes, where species exist in greater density than anywhere else on Earth. This was my first visit to the rain forest, and, little did I know, it would not be my last.

    Of this entire exhibit, the most profound demonstration occurs at the very end. After drooling over various enclosures featuring the likes of venomous snakes, fruit-eating bats, and bat-eating snakes, the final diorama is perhaps anticlimactic to the observer. This final diorama describes a map of the world, highlighting the areas of the planet that support these magical rain forests. The map provides the observer a few moments to consider all the incredible biodiversity recently witnessed while inside the Rain Forest exhibit….but, slowly, huge areas of the map fade away. A speaker describes massive deforestation of tropical rain forests, and a ticker emerges, counting down the acreage of tropical forest cover being destroyed, every second, worldwide. Upon leaving the Cleveland Zoo’s Rain Forest exhibit, one departs with a terrific sense of marvel about the biodiversity of the Earth…but also bitterness and sadness at its destruction. 

Parachuting Red-eyed Treefrog (Agalychnis saltator). J. Folt.
    Sadly, tropical deforestation hasn’t improved much since 1995, and tropical land conversion continues to provide an alarming concern for the maintenance of high tropical diversity. Rates of deforestation are highest in the western hemisphere, where rain forests in Central and South American are disappearing more rapidly than anywhere else. Forests are being cleared for lumber, paved away for commercial cattle, fruit, and tree operations. In Sumatra, slash-and-burn practices blaze away intact forests to make room for palm-oil plantations, destroying precious habitat for the critically-endangered Sumatran Tiger (among countless other species) and simultaneously smogging the island of Singapore, one of the densest human populations on Earth.


    Simply put, the future is bleak for species-rich tropical biomes. Because these ecosystems are home to the world’s most species-rich assemblages, habitat loss and conversion to anthropogenic landscapes threatens more species in the tropics than anywhere else. Given the ‘high-stakes game’ that is conservation in the face of tropical deforestation, a pressing need in conservation biology is to better understand how species respond to increasingly fragmented, human-modified landscapes.

    This topic is not foreign to the Living Alongside Wildlife blog. Although not tropical in nature, one recent essay by David Jachowski discussed this theme, citing an example where elk, once abundant but long extirpated from the eastern United States, are now being reintroduced on the reclaimed devastation that are Appalachian coal lands. In this instance, optimism exists that these degraded landscapes now provide habitat for sustainable populations of economically valuable elk (although, let’s not forget that the integrity of this ecosystem was lost when the first coal was pulled from the ground). Jachowski correctly suggests that, in addition to conserving intact, undisturbed habitat, there is also great value in ‘picking up the pieces’ after human disturbances by conserving wildlife on human-modified landscapes.

    Like many children interested in wildlife, my life twisted and turned as I aged, and my interests shifted away from the natural world. I think for a little while there I was even afraid of snakes…maybe, briefly, for a month. Biology classes in high school and college along with field trips with my brother, however, rekindled my curiosity on the subject, particularly in conservation biology.

    During my senior year at Ohio University, I returned to the Rainforest, but this time I was visiting the real thing. I was working at La Selva Biological Station in the Caribbean lowlands of Costa Rica. Many refer to Costa Rica as being ‘hyper-diverse’: while only possessing about 0.25% of the world’s land area, this country astonishingly accounts for 5% of the world’s biodiversity. La Selva is one of the most well-studied tropical forests in the world and home to a world-class research station. However, despite a great history of research in the wonderful forests of La Selva, biologists know next to nothing about how wildlife is responding to the massive habitat conversion at the regional level.

Primary forest at La Selva Biological Station, Costa Rica. J. Folt.
    Thus, in collaboration with Kelsey Reider, a graduate student at Florida International University in Mo Donnelly’s laboratory, we developed a project to study how amphibians and reptiles respond to habitat conversion to plantation monocultures in this region. Because land-use in Costa Rica is becoming increasingly fragmented by plantation monocultures of fruit, palm, and lumber plantation, we hoped our project would lend more insight to whether tree plantations provide good or bad habitats for conserving biodiversity, an especially important question in a rapidly disappearing but ‘hyper diverse’ forests of Costa Rica. 

Strawberry Poison Frog (Oophaga pumilio). J. Folt.
    We focused on the so-called ‘leaf-litter’ amphibians and reptiles: the group of species that are primarily terrestrial and occur on the forest floor. This guild is particularly charismatic, including one of my favorite childhood species from the Rainforest exhibit at the Cleveland Zoo, the Strawberry Poison Frog (Oophaga pumilio; if someone told my childhood self that my summertime job would be to catch these frogs, I would have lost my marbles!). We performed standardized surveys of these animals in replicated plantations of three tree species: Pentaclethra macroloba, Virola koschnyi, and Vochysia guatemalensis. These trees are native to the region and provide prized lumber. We also sampled the herpetofaunal community in nearby intact primary forest, beautiful mature forest of La Selva Biological Station. Our results from primary forest then provided a benchmark to evaluate whether the plantations supported assemblages of amphibians and reptiles at levels comparable to primary forest or not.

    In conclusion, the results of our study were fairly positive. In many cases, we found the native tree species plantations to support measures of biodiversity at levels comparable to nearby primary forest! Because our plantation species are variable in the fauna they support, we suggest land managers interested in sustainable lumber harvest should utilize plantation mosaics of different tree species to maximize the conservation of the species-rich leaf-litter amphibians and reptiles of lowland Caribbean Costa Rica.

Hog-nosed Pitviper (Porthidium nasutum). J. Folt.
    I will be returning to the rain forest in the future to conduct further field studies on the population and community ecological of tropical amphibians and reptiles. Similarly, future blog posts will likely discuss these subjects to greater or lesser extent, but I also hope to convey the marvels that are life in the tropics, the awesome plants and animals that attracted me as a child and continue to inspire me today. 



Want to Learn More?

Chazdon R.L., C.A. Harvey, O. Komar, D.M. Griffith, B.G. Ferguson, M. Martínez-Ramos, H. Morales, R. Nigh, L. Soto-Pinto, M. van Breugel, & S.M. Philpott (2009). Beyond reserves: A research agenda for conserving biodiversity in human-modified tropical landscapes Biotropica, 41, 142-153 DOI: 10.1111/j.1744-7429.2008.00471.x

Bradshaw, C.J.A., N.S. Sodhi, & B.W. Brook (2009). Tropical turmoil: A biodiversity tragedy in progress Frontiers in Ecology and Evolution, 23, 261-267 DOI: 10.1890/070193

Folt, B., & K.E. Reider (2013). Leaf-litter herpetofaunal richness, abundance, and community assembly in mono-dominant plantations and primary forest of northeastern Costa Rica Biodiversity and Conservation, 22, 2057-2070 DOI: 10.1007/s10531-013-0526-0

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