An assessment of the contribution of honey bees (Apis mellifera) to weed reproduction in New Zealand protected natural areas

Recent concern that honey bees may threaten natural areas by increasing weed abundances through increased pollination was investigated by reviewing the literature to determine which weed taxa surveyed from New Zealand Protected Natural Areas (PNAs) are visited by honey bees. The contribution made by honey bees to weed reproduction was assessed by checking reproductive strategies and pollination mechanisms of a subset of problem weeds. A substantial proportion of surveyed weeds in PNAs are probably visited by honey bees (43%) including half of the problem weeds. However, reproduction of the majority of problem weeds is characterised by plastic reproductive mechanisms and/or simple pollination mechanisms where honey bee influence is low or unimportant. Although honey bees may be important pollinators of some weeds, they probably do not contribute substantially to weed problems.