Healthy Bird Populations Key To Beetle Control On Coffee Farms; Up To $300/Ha In Pest Protection
Birds are providing a valuable ecosystem service on coffee plantations in Costa Rica, finds a new study that quantifies the pest control benefits of preserving tree cover in agricultural areas. The study, published in the journal Ecology Letters, looked at the impact of the coffee berry borer beetle (Hypothenemus hampeii) on coffee yields. The beetle is the only insect that directly consumes coffee berries, making it a major scourge for coffee farmers around the world, costing producers some $500 million a year.
The pest's recent arrival in Costa Rica provided an ideal opportunity to explore how coffee yields may be influenced by the presence of borer beetle predators, like birds and bats. The researchers, led by Daniel Karp of Stanford University, also wanted to understand whether maintaining tree cover in plantations helps reduce crop losses by boosting beetle predators.
After measuring coffee yields, Karp and colleagues set up a classical exclusion experiment. They found that birds, not bats, were the main borer beetle predator.
"Pest infestation doubled in absence of birds," Karp said during a presentation at the June meeting of the Association for Tropical Biology (ATBC) in Costa Rica. "There were no effects with bats."
EDIT
http://news.mongabay.com/2013/0911-coffee-birds-rainforest-atbc.html