The yellow warbler may not pull a perfect latte, but it turns out it's a friend to coffee drinkers all the same. Research in Costa Rica shows that hungry warblers and other birds significantly reduce damage by a devastating coffee pest, the coffee berry borer beetle.
A study found that insectivorous birds cut infestations by the beetle Hypothenemus hampeiby about half, saving a medium-sized coffee farm up to US$9,400 over a year’s harvest — roughly equal to Costa Rica’s average per-capita income. The results, published in Ecology Letters1, not only offer hope to farmers battling the beetle, but also provide an incentive to protect wildlife habitat: the more forest grew on and near a coffee farm, the more birds the farm had, and the lower its infestation rates were.
“Based on this study, we know that native wildlife can provide you with a pretty significant benefit,” says Daniel Karp, a conservation biologist at Stanford University in California, who led the study. “Incorporating their conservation into your management of pests is absolutely something you should do.”