Scales matter: Maximising the effectiveness of interventions for pollinators and pollination

Abstract

Evidence of declines in wild and managed pollinators and pollination services is increasingly being documented around the world. This has driven the development of a wide range of practical management and policy responses which were reviewed in the Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services (IPBES) global assessment of 'Pollinators, Pollination and Food Production'. We take 38 responses from this report as a basis to explore the importance of scale for the effective delivery of an intervention's benefit to pollinators. We considered five scale categories: Spatial, the spatial scale at which the response is most effective; Temporal, the time scale over which the response is most effective; Actors, the number of actors needed for most effectively implementing a response; Social, the sphere of influence or motivation that determines an effective response; and, Sector, the sector(s) of society which should be involved to increase effectiveness. Each scale category was split into multiple levels and we scored each in terms of how important they were for determining the effectiveness of a given response option. Using our combined scores, we aim to explore general trends and raise awareness around the main issues relating to the importance of scale, with illustrated examples from the literature. We show how scales have impacted on the effectiveness of interventions and provide recommendations on how to improve scale matching when planning a response action. While the relative importance of scales and levels for effectiveness was heterogeneous across response options, there were some general patterns. Interventions were only effective when targeted over the right spatial scales over a sufficient period of time and involved all relevant social and sectoral groups and actors.

Addressing pollination deficits in orchard crops through habitat management for wild pollinators

“…That our habitat interventions had no significant effects on the extent of these deficits may be because the uplift in solitary bee numbers resulting from wildflower interventions was not sufficient to increase pollination and reduce deficits measurably. Perhaps the size of the wildflower planting in our landscape context was not sufficient (Faichnie et al, 2021 ), although larger flower plots in some contexts have been found to act as a pollinator sink, reducing visitors to crop flowers (Krimmer et al, 2019 ). Alternatively, the lack of an effect could be because substantial pollination is being delivered by other pollinators that did not respond to our habitat interventions (e.g., bumblebees).…”

Different landscape features within a simplified agroecosystem support diverse pollinators and their service to crop plants

“…Alternatively, they can have undesirable impacts such as sheep blow-fly strike caused by species including Lucilia sericata and C. stygia (Morris 2005). Understanding and accounting for the multiple functional services and risks provided by insects associated with landscape features is necessary to ensure management strategies garner broad community support (Faichnie et al 2021).…”

Co-benefits from tree planting in a typical English agricultural landscape: Comparing the relative effectiveness of hedgerows, agroforestry and woodland creation for improving crop pollination services

“…As fields cycle through cereals, OSR and field beans, the location of the mass-flowering crops will change but the trees will stay fixed and so the efficacy of a given agroforestry scheme on crop pollination will vary year-to-year (of an order similar to that demonstrated in our simulations where the arable cropping pattern remains fixed and the alley locations are shifted). Spatially optimal configurations of intervention will therefore depend on long-term planning within the landscape (Faichnie et al, 2021). Given hedgerows' greater potential for supporting bumblebee abundance, combining agroforestry with hedgerow planting may generate optimal spatial configurations that promote consistent pollination services through the crop rotation cycle (Eeraerts et al, 2021;Martins et al, 2018).…”