Smithsonian Journeys Dispatches

A Q&A with Expert Jim Karr

Q: As a specialist in tropical ecology, ornithology, and stream ecology, you have done extensive fieldwork around the world, including Central and South America, Africa, Southeast Asia, and New Guinea. What kinds of tropical ecology projects have you worked on in Central America? 

A: Most of my research in Central America focused on birds. That work led to the study of interactions between birds and vegetation structure, insects, and undergrowth microclimate (temperature and humidity). My research group also studied fishes in forest streams. The bird research began in 1967 and continued until 2001 when I last collected data in Soberania National Park in central Panama. On that trip, I captured a Rufous Motmot that I first captured 18 years earlier at the same site. Over the years, my students and I studied habitat selection, survival rates, movement patterns, site fidelity, frugivory, and predation on nests of forest birds. Another line of research involved asking why did some bird species go extinct on Barro Colorado Island, Panama, after the island's isolation in Gatun Lake, the lake formed by construction of the Panama Canal in the early 1900s. Research and teaching trips to Costa Rica and Panama have taken me to those countries dozens of times. My longest period of residence in the region was four years in the 1980s. 

Q: In all of your travels to Costa Rica, which places draw you back again and again? 

A: This question is like asking which of my children I love best. Many places draw me back. My favorite natural environments are forests, rivers, and wetlands. Costa Rica has a rich variety of forest types from lowland wet and rain forest to lowland dry forest. And how can I not cherish the beauty and mystery of cloud forest. Rivers and the wetlands and riparian forest that border rivers are centers of interest and biological activity. But human environments also intrigue me, especially the agricultural areas and the crops they produce. One of the best ways to see those products in all their diversity is in the local, typically open-air markets in many towns and villages. To see all of these special places I must also cross the larger landscapes in a region. How are the nature reserves, agricultural lands, and urban centers distributed across a region? How do they fit into the topographic and geological diversity of the region? Are there connections among the natural areas that allow migration from highland to lowland and wet to dry areas? Or are the reserves isolated, small patches of nature unconnected to other natural areas? As landscape architect D. W. Meinig observed, "Landscapes mirror and landscapes matter; they tell us much about the values we hold and at the same time affect the quality of lives that we lead." The Costa Rican people understand Meinig's observation. They lead the world in taking conservation of their landscapes seriously with more than 25 % of the country's land mass protected in national parks and preserves.

Q: Costa Rican mountains are home to extraordinary "cloud forests," of which Monteverde is one. What is a cloud forest and what makes them so special? 

A: Lower montane rain or "cloud" forest is the prevalent forest of upper middle elevations (4,000 to 6,000 ft above sea level) in the Monteverde area. Moisture-laden winds from the Caribbean ascend the mountains, forming clouds that bath the forest in nearly perpetual moisture. Measured rainfall is low in cloud forests compared with rain forest but moisture intercepted by tree canopies makes the forest wetter. The diversity of woody plants is reduced in cloud forest and tree height (up to 100 feet) is shorter than in rain forest. Leaves in cloud forest tend to be smaller and harder than lowland tree leaves. The ground is typically covered with a dense growth of mosses and tree ferns are common. Tree trunks and branches support luxuriant growth of mosses, ferns, orchids, lichens, and bromeliads. Cloud forests are home to many species found nowhere else with high diversity for groups that are especially adapted to these perpetually cool, moist environments. These include, for example, orchids, bromeliads, insectivorous plants, ovenbirds, and tanagers.

Q: A highlight of Monteverde is the Bat Jungle where visitors can observe different species of fruit-eating bats in a simulated forest environment. What other kinds of foods do Costa Rican bats consume? Have Costa Rican bat populations been affected at all by the white nose syndrome that is decimating bat populations in North America and Europe? 

A: More than 200 species of bats live in Costa Rica. The Bat Jungle's interactive displays, exhibits, and simulated forest environment are designed to give a new appreciation for these often misunderstood but important and intriguing creatures of the night. Live bats in the simulated forest are all fruit eaters and visitors normally see them flying around and feeding on bananas and other fruit. The high diversity of bats in Costa Rica is possible because each species specializes on different foods: fruit, nectar, insects, frogs, fish, birds, lizards, blood, or mice. In addition to discussing foods eaten by bats, Bat Jungle guides discuss echolocation, where bats roost, how bats care for and carry their young, and bat conservation. Fortunately, Costa Rican bats are not yet threatened by the white nose syndrome, an infectious and lethal cold-loving fungus that threatens so many of the cave dwelling bats of North America. 

Q: How is it that Palo Verde can be both wetland and tropical dry forest? What range of habitats will Smithsonian travelers see on the float safari on the Tempisque River? 

A: Palo Verde National Park is in the lowlands of the Tempisque River, Guanacaste Province, in the Pacific Northwest region of Costa Rica. The region receives more rain each year (70 inches) than most regions of North America. But most of that rain falls in the seven-month wet season (May-Nov), leaving an extended dry season with little or no rain. The region's dry tropical forest survives by dropping most leaves during the dry season, much as temperate deciduous forests lose their leaves during the northern temperate winter. The lack of rain in the dry season contrasts with the substantial rainfall (6 to 12 inches) each month during the 6-month rainy season. Water accumulates in marshes, seasonal pools, and the Tempisque River floodplain during the rainy season, creating massive seasonal wetlands that are prime breeding areas for thousands of wetland birds. Smithsonian travelers motor upstream on the Tempisque River and along a small tributary. You experience the tidal changes of the lower river, as well as pass through adjacent mangrove forest, dry tropical forest, and areas cleared for pasture and agriculture. Birds (black hawk, egrets, and herons) and howler and white-faced monkeys are common during the float safari. Palo Verde National Park is on the list of wetlands of international importance because of the diversity of plants and animals and the large number of breeding birds. The park also protects one of the most endangered Central American ecosystems, tropical dry forests that once covered much of Pacific coastal Central America.

Q: People around the world love Costa Rican coffee. What makes Costa Rica coffee so special? Do Costa Ricans drink a lot of coffee, too? 

A: Environmental conditions, dedicated farmers, and government policy come together in Costa Rica to produce the ideal cup of coffee. The central highlands of Costa Rica have climate (temperature and rainfall) and slightly acidic, volcanic soils that are ideal for production of coffee—the "Golden Grain" as it is called in Costa Rica. Costa Rican farmers have nurtured their coffee plants and protected those soils to ensure sustainable production of high quality coffee for two centuries. Robusta and Arabica dominate world coffee consumption, however, Costa Rica prohibits production of robusta coffee in the country. Robusta is more resistant to disease and weather problems, and easier and cheaper to grow than arabica. But arabica beans have moderate aroma and body and produce a superior grade of coffee because it contains half the caffeine of robusta as well as more aromatic properties and desirable flavorings. Costa Ricans ensure the quality of their coffee for the world and for their own consumption. Costa Rica has the highest per capita consumption of any coffee-growing country. As in other parts of the world, coffee ties together the rich and the poor in Costa Rica. Coffee helped to transform the Costa Rican economy, a reality tied to the importance of coffee in the world economy; globally, coffee is the second most traded commodity, after oil. Coffee also has transformed consumer behavior, working patterns, and even fostered the democracy that flourishes today in Costa Rica.

Q: The Smithsonian group will visit both Poas and Arenal volcanoes. What role did volcanoes play in the creation of Costa Rica and its diverse ecosystems, stunning biodiversity, and productive agriculture. 

A: Until just a few million years ago, no land connected North and South America. Interaction of the Earth's crustal plates caused the land that is now Costa Rica and Panama to rise above sea level and connect those two continents about three million years ago. As a result, Costa Rica, a country a bit smaller than West Virginia, has four major mountain ranges and seven active volcanoes. Visitors can see venting steam and smell volcanic gases, evidence of geological processes that continue today, during visits to Poas and Arenal volcanoes. For many millennia Costa Rican volcanoes have provided nutrient- and mineral-rich building blocks for soils that nurture Costa Rica's natural ecosystems and modern agriculture. Costa Rica's geological diversity and its position as an active mixing zone for the plants and animals of North and South America provide ideal conditions for diverse ecosystems (coral reefs, mangrove forest, wet and dry lowland forest, cloud forest, montane oak forest, elfin forest, and so on). Costa Rica is home to 210 mammal, 35,000 insect, 820 bird, and 9,000 plant species (including 900 trees and 1,500 orchids). From the north came wrens, wood warblers, cats, deer, bears, oaks, and mistletoe. From the south came antbirds, parrots, armadillos, opossums, porcupines, orchids, bromeliads, and heliconias.