May 13, 2022

Birds and bees boost coffee production •

Birds are important visitors to coffee plantations as they feed on insects, such as the coffee berry borer, which would otherwise harm coffee beans or plants. Moreover, pollinating insects are crucial for the fertilization of coffee flowers, so they are also welcome in coffee plantations. But a new study, conducted by scientists from Latin America and the United States, indicates that these two natural forces have more impact when they work together.

“Until now, researchers have typically calculated nature’s benefits separately and then simply added them together,” said lead author Alejandra Martínez-Salinas of the Center for Research and Higher Education in Tropical Agriculture (CATIE). in Costa Rica. “But nature is an interactive system, full of important synergies and trade-offs. We show the ecological and economic importance of these interactions, in one of the first experiments at realistic scales in real farms.

Researchers manipulated insect and bird visits to coffee plants at 30 different coffee farms in the United States and Latin America. They excluded birds by covering the plants with large nets and excluded pollinating insects by using small lace bags placed over the flowers.

The experts set up four experimental scenarios: allow bird activity only (pest control), bee activity only (pollination), no bird or bee activity, and finally, leave the trees in a natural state, where bees and birds were free to pollinate. and eat insects at will.

The results, published today in the Proceedings of the National Academy of Sciencesshow that the combined positive effects of birds and bees on fruit set, fruit weight and fruit uniformity – all important factors in determining quality and price – were greater than the sum of their individual contributions.

Overall, the study indicated that without birds and bees (and other pollinating insects), the average yield fell by almost 25%. This represents a revenue reduction of approximately $1,066 per hectare, which would be very significant for the $26 billion coffee industry. Everyone involved, including consumers, farmers and the companies that brew and package coffee, depend on nature’s unpaid labor for this popular product.

“These results suggest that past assessments of individual ecosystem services – including major global efforts like IPBES [Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services] – may in fact underestimate the benefits that biodiversity brings to agriculture and human well-being,” said Taylor Ricketts of the University of Vermont. “These positive interactions mean that ecosystem services are more valuable together than apart.”

The researchers were very surprised to find that many of the birds providing pest control in coffee plantations in Costa Rica were migrants who had traveled thousands of miles from Canada and the United States. In fact, some spent their summers in Vermont, exactly where the UVM scientists involved in this study originated from.

The team is also studying the impact of changing agricultural landscapes on the ability of birds and bees to provide benefits to coffee production. They are supported by the US Fish and Wildlife Service through the Neotropical Migratory Bird Conservation Act.

“One of the important reasons we measure these contributions is to help protect and conserve the many species we depend on and sometimes take for granted,” said Natalia Aristizábal, a doctoral student at the Gund Institute for Environment in the United States. UVM and the Rubenstein School of Environment and Natural Resources. . “Birds, bees and millions of other species support our lives and livelihoods, but face threats such as habitat destruction and climate change.”

In addition to Martínez-Salinas (Nicaragua), Ricketts (USA), Aristizábal (Colombia), CATIE’s international research team included Adina Chain-Guadarrama (Mexico), Sergio Vilchez Mendoza (Nicaragua), and Rolando Cerda (Bolivia).

By Alison Bosman, Personal editor