The contribution of non-managed social bees to coffee production: new economic insights based on farm-scale yield data

• Published in: Agroforestry systems Vol. 73; no. 2; pp. 109 - 114
• Main Authors: Veddeler, Dorthe, Olschewski, Roland, Tscharntke, Teja, Klein, Alexandra-Maria
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2008; Springer; Springer Nature B.V
• Subjects: Agricultural production; Agriculture; Agroforestry; Agronomy. Soil science and plant productions; Apoidea; Bees; Biological and medical sciences; Biomedical and Life Sciences; Coffea arabica; Coffee; correlation; crop production; Data processing; density; Economics; ecosystem services; Ecuador; Farms; Flowers; Forestry; Fruit set; Fruits; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; insect pollination; Life Sciences; Pollen; Pollination; Pollinators; profitability; Resource allocation; Shade; Shrubs; species diversity; Studies; Supplementation; Trees; yields; South America; Ecuador; America; Stingless bees; Farm-wide yield; Honey bee; Ecosystem service; Pollination; Economic analysis; Insect pollination; Insecta; Tropical zone; Apidae; Stimulant plant; Coffee; Apoidea; Dicotyledones; Ecosystem; Angiospermae; Rubiaceae; Aculeata; Coffea arabica; Apis; Social insect; Arthropoda; Spermatophyta; Yield; Hymenoptera; Invertebrata; Agroforestry
• ISSN: 0167-4366; 1572-9680
• DOI: 10.1007/s10457-008-9120-y

Fruit set and quality of highland coffee ( Coffea arabica ) have been experimentally shown to be higher with bee-mediated or manual pollen supplementation than with autonomous self-pollination. Based on extrapolation from these small-scale experiments, very substantial monetary values for the pollination service have recently been suggested. However, previous research has not included direct measurement of coffee yield at a farm level in relation to pollinator activity, testing if pollinators are not only limiting fruit set and quality, but also coffee yield and farm profit. The extrapolations from small-scale experiments may be subject to error, because resource reallocation during fruit development, associated with enhanced pollination, was neglected, and many studies were restricted to a single coffee farm, limiting the validity of extrapolation. Here, we investigate the relationship between coffee yield and the community of coffee flower-visiting bees on 21 farms in Ecuador, where coffee is grown under tree shade. Our data show, for the first time on a farm-scale, that coffee yield was positively related to the density of non-managed, social flower-visiting bees per coffee shrub, but not to the number of inflorescences per shrub. Our data revealed that a fourfold increase in bee density was associated with an 80% increase in yield and an 800% increase in net revenues. Consequently, in our study higher yield associated with increased pollination generated higher revenues per hectare, so that farm profit was higher when bees were abundant.