April 30, 2015

The Connection between Biodiversity and Coffee Agriculture

Amanda Caudill, Smithsonian Migratory Bird Center

When I tell people about my research with biodiversity and coffee farms, most people look at me confused and ask, “Wait, what does coffee have to do with biodiversity?” I understand that this question is not unfounded. Although about 1 billion cups are coffee are consumed worldwide daily–most people do not link the dark, velvety liquid in their coffee cup with the diverse and abundant wildlife that inhabit the lands where that coffee is grown.

Ripening coffee beans

The ‘coffee bean’ is the seed of the coffee cherry—a fruit that can take 3-4 years to produce after a coffee tree is planted. Once they are bright red, the fruit is ripe for the picking. Photo taken by Amanda Caudill.

Coffee can be good for both people and for wildlife

The reality is that coffee farms can provide a refuge for wildlife. Coffee is grown in tropical areas that host high levels of plant and animal diversity. The way that coffee farms are managed varies widely–from a monoculture of coffee plants with little or no shade trees intermixed with the crop (often referred to as “sun coffee”) to farms that with many different types of trees and vegetation interspersed between the coffee plants (also known as “shade coffee”). The former provides little habitat value to wildlife, whereas the latter, which mimics natural forests, provides food, shelter, and habitat for the animals that live in and around these coffee farms. Shade coffee farms can also support ecosystem services such as soil erosion reduction, water clarification, and crop pollination.

As a research scientist with the Bird Friendly Coffee program within the Smithsonian Institution’s Migratory Bird Center, my work involves conducting field research to determine how to provide the best habitat for wildlife on these farms. I am interested in sustainable solutions for the protection of natural resources. Agricultural crops grown sustainably could be a win-win solution to protect biodiversity and ecosystem services while also providing for human livelihoods. I have done research in India, Mexico, and Costa Rica to understand what makes good habitat for mammals in coffee farms–a group that is understudied in coffee agroforestry research (see Scientist At Work and Smithsonian Migratory Bird Center).

Farming with pollinators can be beneficial to production and to nature

My most recent research venture, however, looked at bee communities in coffee farms in Costa Rica. Arabica coffee, which is the most abundant type of coffee in Latin America, is self-pollinating—meaning it does not need bees for the coffee plants to fruit. Interestingly though, if the coffee plants are pollinated by bees, there can be a 30-50% increase in coffee yield. Thus, it is in the interest of the farmers to create an attractive environment for the bees.

Native bee pollination

Native bee pollinating a coffee flower in southern Costa Rica. The bee stores the pollen it collects in an area called the scopa on the legs, which on this bee are the white bulges full of pollen. Photo taken by Amanda Caudill.

Science at work: the challenges and rewards of studying biodiversity in agroforestry systems

I spent the last couple of months living and working on a coffee farm in the mountains of southern Costa Rica. Over the years, I learned that fieldwork is unpredictable. To me, that is what makes it fun and interesting, but also challenging. Pollination studies in coffee require a lot of patience. The coffee flowers are open for only three days before they wilt, dry up, and fall to the ground. All of your data for the pollination takes place in only a few days, so you have to be ready to go and have everything in place for that first day of flowering.

But to collect data on the bees and pollination, you need coffee flowers…for the coffee flowers to bloom, you need rain…and this year, there was a drought in the region of our study site. The coffee plants had small flower buds, but they were in a holding pattern, refusing to open until it rained. Every day, my field team and I hiked through our sites, examining the buds trying to assess if they were growing and when they would open. We monitored the clouds, as if we were meteorologists, trying to predict when the rains would come. We wearily crossed the days off the calendar, watching as the X’s got closer and closer to our scheduled departure date. Then finally, the rains came and the coffee flowers bloomed, infusing the farm with a jasmine-like scent. Bees swarmed, gathering pollen from the flowers and my research team and I were finally able to collect our data!

Coffee flowers

The coffee flowers blossomed after the rains fell. Photo taken by Amanda Caudill.

I will use the information that we collected to determine what habitat requirements within the coffee farms are related to higher bee diversity. The results of this study will provide more information to farmers about how they can provide a better habitat for bees on their coffee farms and increase their coffee yields. I am interested to see what we find out!

Amanda Caudill, PhD is a postdoctoral research scientist at the Migratory Bird Center of Smithsonian Conservation Biology Institute in Washington, DC. Her research focuses on sustainable agriculture as a means to provide wildlife habitat and conserve biodiversity, while providing for human livelihoods. Special thanks to Robert Rice, Smithsonian Conservation Biology Institute, and to the field crew for the Costa Rica pollination research: Julia Brokaw, Dejeanne Doublet, and Kristian Moore.


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  • Linda Moyher
    May 27, 2015 at 7:35pm

    Hi again, I forgot to ask what species is the bee in your photo is and also the variety of coffee trees you were working with.
    Thanks again,

  • Linda Moyher
    May 27, 2015 at 7:29pm

    Which bees are you studying? Native bees or European and African? Does it make a difference? On our farm the European bees are very few since local farmers sprayed flowering crops and killed ours and other neighbors’ hives years ago. On the bright side it may give the natives a better chance but who knows if they like coffee? Truth is I see some of them on the flowers but not en mass like we used to see the European bee.
    Did you count the different insects-wasps, flies- on the flowers? I see numerous other insects digging around inside the coffee flowers but I have no idea of how well they may or may not do the job. From my perspective, getting rid of the non-native insects may give our local pollinators a better chance to thrive, but that is just conjecture. Maybe they don’t like coffee. We had hoped a bee keeper would have brought a hive or two for the flowering, but he didn’t need our farm. Soon I hope to post a photo or two on our Facebook page.
    Any thoughts on the subject? Looking forward to reading your study.

    • Amanda Caudill
      June 1, 2015 at 3:24pm

      Hi Linda –
      Thank you for your comments and interest in the study. We are looking at any bees on the coffee farm that pollinate the coffee flowers. We are in the process of identifying each of the species, but it looks like most of them were native bees. We made note of other insects such as a wasps and flies on the flowers, but they will not be included in the study. All of coffee on the farm where this study took place (southern Costa Rica) was arabica coffee. There are a couple of different varietals planted. Good luck with your crop – where is your farm located?
      Take care,