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The widespread use of protective covers in horticulture represents a novel landscape‐level change, presenting the challenges for crop pollination. Honeybees (Apis mellifera L) are pollinators of many crops, but their behavior can be affected by conditions under covers. To determine how netting crop covers can affect honeybee foraging dynamics, colony health, and pollination services, we assessed the performance of 52 nucleus honeybee colonies in five covered and six uncovered kiwifruit orchards. Colony strength was estimated pre‐ and postintroduction, and the foraging of individual bees (including pollen, nectar, and naïve foragers) was monitored in a subset of the hives fitted with RFID readers. Simultaneously, we evaluated pollination effectiveness by measuring flower visitation rates and the number of seeds produced after single honeybee visits. Honeybee colonies under cover exhibited both an acute loss of foragers and changes in the behavior of successful foragers. Under cover, bees were roughly three times less likely to return after their first trip outside the hive. Consequently, the number of adult bees in hives declined at a faster rate in these orchards, with colonies losing on average 1,057 ± 274 of their bees in under two weeks. Bees that did forage under cover completed fewer trips provisioning their colony, failing to reenter after a few short‐duration trips. These effects are likely to have implications for colony health and productivity. We also found that bee density (bees/thousand flowers) and visitation rates to flowers were lower under cover; however, we did not detect a resultant change in pollination. Our findings highlight the need for environment‐specific management techniques for pollinators. Improving honeybee orientation under covers and increasing our understanding of the effects of covers on bee nutrition and brood rearing should be primary objectives for maintaining colonies and potentially improving pollination in these systems.

Many pollinator species visit multiple crops in multiple regions, yet we know little about their pollination service provisioning at local and regional scales. We investigated the floral visitors (n = 13,200), their effectiveness (n = 1718 single visits) and response to landscape composition across three crops avocado, mango and macadamia within a single growing region (1 year), a single crop (3 years) and across different growing regions in multiple years. In total, eight wild visitor groups were shared across all three crops. The network was dominated by three pollinators, two bees (Apis mellifera and Tetragonula spp.) and a fly, Stomorhina discolor. The visitation network for the three crops was relatively generalised but with the addition of pollen deposition data, specialisation increased. Sixteen managed and wild taxa were consistently present across three years in avocado, yet their contribution to annual network structure varied. Node specialisation (d’) analyses indicated many individual orchard sites across each of the networks were significantly more specialised compared to that predicted by null models, suggesting the presence of site-specific factors driving these patterns. Identifying the taxa shared across multiple crops, regions and years will facilitate the development of specific pollinator management strategies to optimize crop pollination services in horticultural systems.

Effective pollination is a complex phenomenon determined by the outcome of the interaction between pollen transfer and a plants' pollinator dependency, yet most studies investigate pollinator effectiveness without consideration of plant mating system differences. We investigated pollinator effectiveness in three types of blueberry that differed in their degree of pollinator dependency as measured by plant mating system: two self‐compatible highbush cultivars and one partially self‐incompatible rabbiteye cultivar. We quantified pollinator effectiveness as a function of the fruit set and fruit weight resulting from single and multiple floral visits (2–15 visits), in comparison with estimates of fruit set and fruit weight resulting from experimental pollination treatments (open‐pollination, cross‐pollination and self‐pollination). Single‐visit effectiveness of fruit set was similar across pollinator taxa but considerably higher in both self‐compatible cultivars. The probability of fruit set in all three blueberry types improved in response to an increasing number of visits, but this relationship was steeper in self‐compatible cultivars: >90% probability of fruit set was achieved in three to five visits. In the self‐incompatible rabbiteye cultivar, 58% fruit set was achieved with 15 visits. Multiple visits improved fruit weight by 27%–48% in self‐compatible cultivars, but there was no relationship in rabbiteye. Pollination deficits in fruit set and fruit weight due to self‐pollination were most pronounced in rabbiteye. Synthesis and applications. Improved understanding of cultivar‐level mating system differences in plants will inform pollination planning and management in agroecosystems. Self‐compatible (highbush) cultivars require less floral visitation to maximize fruit production. Therefore, these cultivars may be best suited to landscapes in which pollinator abundance is low, such as intensive and/or simple landscapes. In contrast, self‐incompatible (rabbiteye) cultivars may benefit from the implementation of mixed‐cultivar crop row plantings to facilitate cross‐pollination.

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