Estimated annual value (US$ millions for 2005) of all insect and managed honeybee pollination to the Western Cape deciduous fruit industry (South Africa) using traditional and revised factors.

Values were calculated using standard estimates of crop dependence on insect pollination and on the proportion of pollinators that are likely to be managed honeybees [10]; as well as using estimates of crop dependence on insect pollination from previous literature, and proportion of managed honeybee pollination derived from local industry figures.
*Factors are based on experimental evidence (Table S3).
†Number of managed honeybee colonies that need to be used for each of the deciduous fruit crops (2/ha for apples; 4/ha for pears; 1/ha for apricot cultivars; 1/ha peaches/nectarines; 6 for plums/prunes; 0 for grapes; adapted from [38] to best reflect current trends in the Western Cape).
‡Reported use of honeybee colonies for commercial pollination in the Western Cape deciduous fruit industry ([14], personal communications from the South African Bee Industry Organisation and Deciduous Fruit Producers' Trust).
#More managed honeybee colonies are used than recommended, thus proportional contribution is at maximum.