Description
Pollination studies generally emphasize bees, although flies are abundant flower visitors and may remain active under conditions in which bees do not forage. Pollination success depends not only on how much pollen is carried but also if the pollen is carried on body surfaces likely to contact flower stigmas. We compared exposed pollen load and its body placement on 527 bee (Hymenoptera) and fly (Diptera) specimens collected in a commercial apple orchard. Pollen was quantified by direct microscope counts for 376 specimens and hemocytometer wash counts for an additional 151 specimens. Pollen concentrated within scopae and corbiculae, which is less available for transfer, was excluded from our counts. High pollen loads among apid and megachilid bees contrasted with low loads among chironomid flies. Bees carried nearly four times more exposed pollen than flies, averaging 426 grains per specimen compared with 108 for flies. Megachilidae and Apidae carried the largest pollen loads among bees, whereas Muscidae carried the largest pollen loads among flies. Bees were more likely to carry pollen on the head and thorax, body regions more likely to contact floral stigmas, whereas flies were more likely to carry pollen on the legs and wings. Whereas flies carried substantial exposed pollen loads, bees carried nearly four times more pollen and were more likely to carry it on the head and thorax, where it may be more likely to contact floral stigmas.
Publication Date
2026
Document Type
Article
Keywords
apple orchard; Diptera; Hymenoptera; pollen body placement; pollen load; pollinator community
Disciplines
Biology
Department
Biology
Recommended Citation
Warren, Robert, "Bees carry more exposed pollen than flies and on body regions well placed for floral contact" (2026). Biology Faculty Datasets. 16.
https://digitalcommons.buffalostate.edu/biology_data/16
