Using non-bee and bee pollinator-plant species interactions to design diverse plantings benefiting crop pollination services

Abstract

<p>Protecting, establishing and managing biodiverse semi-natural habitats is one strategy within the concept of ecological intensification of agriculture that supports insect pollinator abundance and diversity in agroecosystems. However, without accounting for species-level relationships between insects, crops and non-crop vegetation, diverse semi-natural habitats may not lead to improved crop pollination, and could create pest reservoirs. Possibly thousands of non-bee insect species contribute to global crop pollination, but research has largely focussed on bees. Thus, key information to best manage habitats that target wider crop pollinator diversity and abundance is lacking. We demonstrate the concept of designing mixed species native plantings (a type of semi-natural habitat) based on plant-insect interactions to increase abundance and diversity of non-bee and bee crop pollinators in an intensively managed agricultural landscape. We used existing refereed and grey literature to identify and anticipate interactions between pollinators, natural enemies and pests with native plants and crop species to design and establish plantings on three farms. We anticipated the designed plantings would support 21 pollinating species, 20 of which were verified in observational surveys 5 years post-establishment. While anticipated bee-plant species interactions were largely confirmed, actual networks of the non-bee pollinators, were larger and more complex than expected, indicating the plantings were particularly effective in supporting these interactions. Most immature life-stages of non-bee pollinators were not directly supported by plantings and separate strategies should consider larval requirements. Presenting the plant-pollinator networks to relevant industries has been a powerful tool for incentivising their support for designed habitats on farms.</p>