For the love of coffee
Who loves coffee? I do, I do! Coffee, as we know it, is cultivated as varietals of two species of African shrubs. You may recognize the names as Arabica (Coffea arabica) and Robusta (C. canephora). Coffee is now grown in tropical regions around the world, but it is rather specific in its ecological needs. I know far more about coffee agriculture than you’d expect from a herpetologist. Why? Because I have spent a lot of time on coffee plantations in Mexico and Guatemala. A lot of time. Why? Because coffee plantations (fincas, in Spanish) are great base-camps for field biologists. They usually have some basic, or even very nice, infrastructure of trails, dirt roads, maybe even a bunkhouse to sleep in. Because you can only be there with the permission of the owner, you and your gear are effectively pretty safe. So, we use fincas as base camps in order to survey the surrounding forests. Even better, often the fincas themselves can produce very interesting and important records and samples of the local fauna. This fact relates to the basic ecology of the coffee plants.
Coffee grows best in relatively cool, humid, and shaded habitats. So, forget about the sweltering lowland rainforests and swampland of Central America; this is not where coffee comes from. Look up, to the mid-elevations of the wet slopes of the surrounding mountains. In southern terms, think “Chattanooga vs. Savannah.” Up there, you will find a zone that legendary herpetologist L. C. Stuart called “the Coffee Belt” lying at elevations between about 600–1300 meters. Here, the zone in which coffee grows best is situated between the warmer Corozo Belt (named for the Corozo Palm, another valuable plant, and a whole different story) below, and the cooler, foggy cloud forest above. As such, coffee is almost invariably grown on mountain slopes, some of them very steep.
A typical coffee finca is situated within the Coffee Belt, on the moister slope of mountains—which usually means the slopes facing humid winds coming in from the oceans. The plants, especially the young ones, need to be shaded from the direct sun. In establishing a new finca, the understory of the original forest is removed and replaced with coffee plants, leaving the original canopy forest intact. Coffee plants shed a lot of leaves, so a thick and moist leaf-litter layer develops under the cash crop. From a physical and ecological perspective, these canopy-shaded coffee groves are fair approximations of the original forest and offer a decent representation of the original fauna. In this sense, coffee production really is not the worst thing that can happen to a piece of montane rainforest. And, this is why I have spent so much time on coffee fincas. I have spent many days slowly working my way down the lines of coffee plants, raking gently through the leaf litter underneath, looking for amphibians and reptiles. During the harvest season, I step around the coffee pickers and try to stay out of their way. Stretching my stiff back, I look up and see toucans, various raptors, hummingbirds, tamanduas, monkeys and other native species. Back in the leaf litter, I also scare up rodents, sometimes a sleeping rabbit, and very many invertebrates, including huge, bright-blue earthworms and angry terrestrial crabs. You get the idea – coffee fincas can be great places for people like me! Indeed, away from the actual coffee plants, the mill building is where they separate the seeds (the part we like so much!) from the small fruit and husk. The huge piles of decomposing husks behind the mill are, in fact, the most likely places to find caecilians (a bizarre limbless group of amphibians), which otherwise are extremely difficult to find.
Similarly, other species that are difficult to find in fully intact virgin rainforest become very much more abundant in these human-modified rain-coffee-forests. The example of one snake is so dramatic, that we typically call it the coffeebean snake (Nina sebae) in English. I can count on one hand the number of coffeebean snakes I have found in untouched forests, but I have sometimes found a dozen or more a day beneath coffee plants. On lands in the Coffee Belt where the entire forest has been removed, for example, to grow corn or graze cattle, virtually all of the creatures I’ve mentioned above disappear. Conservationists are eager to work with fincas and coffee companies to encourage well-managed plantations that have some very real value in terms of biodiversity. Importantly, coffee production provides ever-important jobs for local people. Is this a conservation story too good to be true? In some ways, yes.
Fincas in Guatemala all began as shade-grown coffee, and apparently all of the Arabica variety (but I’m not certain of this last point). Sometime in the 1970s plantations around the world started to switch to a new technique, called full-sun coffee production. These plants are varietals, especially of Robusta, that can tolerate warmer temperatures. The moist leaf-litter layer beneath the plants, however, dries out and does not decompose well. So, these plants need more fertilizer. The benefits here are that in full-sun cultivation, with fertilizer, the plants produce more crop and do so more quickly. Tolerance of warmer temperatures also means that production can be expanded to lower elevations, into the Corozo Belt. Coffee purists, like wine sommeliers, argue that shade-grown coffee, and specifically Arabica, is far superior to full-sun coffee of either species. I will stay out of that argument, but there clearly was a waiting market for these full-sun coffee beans. Even if they may be inferior in flavor, they certainly were less expensive because they matured quickly, produced more crop, and could be grown over a wider range of elevations. From what I can recall, fincas in Guatemala started converting shaded groves to full-sun groves, and expanding their operations down slope, in the mid-1980s.
I can attest personally to the biodiversity-value of shade-grown coffee. Full-sun operations are biological deserts, and we long ago stopped wasting our time in them looking for amphibians and reptiles. So, when properly verified, the marketing term “Shade Grown Coffee” really has a lot of value, and it apparently tastes better! And then, there is the all-important certifications of “organic” and fair-trade. We can discuss those perhaps in a future column.
Joe Mendelson, PhD
Director of Research