Diurnal insect visitation patterns to 'Hayward' kiwifruit flowers in New Zealand

Abstract

Different pollinators may vary in their temporal flower-visitation patterns within crops, potentially extending the period pollination may occur. To assess whether this could be the case in kiwifruit, we conducted standardised observational surveys of insects visiting kiwifruit flowers within 31 orchards at three times: 10:00-11:00, 12:00-13:00 and 14:00-15:00 hr. Honey bees (Apis mellifera) represented 92% of visitations (n=5474), but temporal abundances were uneven (predicted abundances were lower at 14:00-15:00 hr). Predatory hover flies (Melangyna, Melonostoma, Allograpta spp.) also showed an uneven temporal pattern. There were no significant differences in the temporal abundances for buff-tailed bumble bees (Bombus terrestris), rattailed hover flies (Eristalis, Helophilus spp.), March flies (Dilophis nigrostigma), flower longhorn beetles (Zorion guttigerum) or the native bees (Leioproctus and Lasioglossum spp.) although, in some cases, low numbers may have masked potential unevenness trends. Variation in diurnal flower-visitation patterns among insects suggests the potential for complementarity between different pollinators.