Data-set: The economic cost of losing native pollinator species for orchard production

1. The alarming loss of pollinator diversity worldwide can reduce the productivity of pollinator-dependent crops, entailing potential economic impacts. However, it is unclear to what extent the loss of a key native pollinator species affects crop production and farmer's profits.2. By experimentally manipulating the presence of colonies of honey bees and a native bumble bee species (<i>Bombus pauloensis</i>) in eight apple orchards in South Argentina, we evaluate the impact of losing natural populations of a key native pollinator group on <i>i</i>) crop yield, <i>ii</i>) pollination quality, and <i>iii</i>) farmer’s profit. To do so, we performed a factorial experiment of pollinator exclusion (yes/no) and hand pollination (yes/no).3. Our results showed that biotic pollination increased ripe fruit-set by 13 % when compared to non-biotic pollination. Additionally, fruit-set and the number of fruits per apple tree was reduced by less than a half in those orchards where bumble bees were absent, even when honey bees were present at high densities. Consequently, farmer’s profit was 2.4-fold lower in farms lacking bumble bees than in farms hosting both pollinator species. The pollination experiment further suggested that the benefits of bumble bees could be mediated by improved pollen quality rather than quantity.4. <i>Synthesis and applications</i>: Our findings highlight the pervasive consequences of losing key pollinator functional groups, such as bumble bees, for apple production and local economies. Adopting pollinator-friendly practices such as minimizing the use of synthetic inputs or restoring/maintaining semi-natural habitats at farm and landscape scales, will have the double advantage of promoting biodiversity conservation, and increasing crop productivity and profitability for local farmers. Yet because the implementation of these practices can take time to deliver results, the management of native pollinator species can be a provisional complementary strategy to increase economic profitability of apple growers in the short term.