Estimating crop pollinator population using mark–recapture method

Abstract

Xylocopa species are large solitary bees, which are effective pollinators of yellow passion fruit, a self-incompatible crop dependent on pollination for fruit production and economic viability. We tested the mark–recapture method to estimate these bees' population size in a passion fruit commercial orchard in Central Brazil. We collected data during 3 years and population was estimated as 118, 339, and 1,032 individuals. Population size and abundance of Xylocopa bees were higher in the last studied year. These bees maintained 32.5 % of natural fruit set, above economic viability levels, and higher than other commercial orchards, although population size showed no direct correlation with natural fruit set. Improvement of nesting site may explain population increase, reinforcing the importance of management. Our results showed that the mark–recapture technique can provide reliable estimates of Xylocopa bees population size and, thus, be useful in monitoring population trends.