Written evidence submitted by University of Reading, School of Agriculture, policy and Development (INS0032)

The Role of Bees and Other Pollinators in the UK Food System – An Evidence Update

Potts S.G., Breeze T.D., Garratt M.P. & Senapathi G.D. (University of Reading)

About this submission: This submission was prepared by the University of Reading’s School of Agriculture, Policy and Development. The authors are all highly cited researchers in the field of pollinator ecology, policy and economics. We have contributed to multiple science-policy reviews on pollinators, including leading the UN IPBES thematic assessment on pollinators, contributing to the Dasgupta Review on the Economics of Biodiversity, coordinating the evidence summary for Defra’s National Pollinator Strategy (2014) and it’s revision (2022), contributed to the development of the UK and EU pollinator monitoring schemes are members of DEFRA’s Pollinator Advisory Steering Committee. This review is presented as an update of evidence from our own research, following two previous evidence reviews that the authors contributed to (Vanbergen et al., 2014; Steele et al., 2019), which have served as the basis of the UK Pollinator Strategy and it’s Update.

Summary

Pollination by bees and other insects adds over £600M to UK crop production annually, however they are under pressure from a combination of habitat loss, changes to landscape management, chemical insecticides and climate change, resulting in changes in abundance, diversity and ranges as well as sub-optimal crop yields in the UK and abroad. Although agri-environment management interventions to support pollinators has been demonstrated to be effective at reducing these gaps, their uptake remains poor and their effectiveness is limited by unsympathetic management and little co-ordination between actors. Raising awareness and engagement among farmers and other food system stakeholders and monitoring pollinator populations are important steps to building resilient, diverse pollination services to underpin future food and nutritional security.

How are pollinators economically valuable?

Bees and other insects add over £600M to UK crop production. Pollination services are important to many UK crops, increasing yield and quality in many high value fruit crops like apples and strawberries and broadacre crops like field beans and oilseed rape (Breeze et al., 2021). Much of this value is concentrated in south-east England.

The value of pollination goes beyond the farm. By increasing supplies relative to demand, reducing waste and supporting crop diversity, pollination services provide benefit to processors, retailers, consumers and other food system actors, pollination services have significant value across the food system (Breeze et al., 2022). The value of pollination services is therefore often under-estimated. Many of these actors also generate indirect pressures on pollinator populations by acting as drivers of land management practices (e.g. western consumer demand driving deforestation in developing countries to make room for agriculture – Green et al., 2019).

The UK Is currently the 4th largest importer of pollinated crops and is highly vulnerable to declines of pollination services overseas. The UK has a highly globalised food system and imports pollinated crops such as coffee, cocoa, mangoes and soy from across the world. As such, pollinator declines in other countries, such as Malaysia, South Africa and France, could have a significant impact on processors, retailers and consumers in the UK (Murphy et al., 2022).

The importance and value of pollination services is likely to increase. Due to climate change, new technology, shifts in market demands and policy drives towards sustainable food security, a range of underutilized crops such as soy, sunflower and apricots, are likely to be grown across the UK in the next 20-30 years (DEFRA, 2021). Many of these are highly dependent upon pollination for optimal yield (Klein et al., 2007), meaning that dependence is likely to increase.

Figure 1- Links between pollination services and food system actors (from Breeze et al., 2022).

What are the pressures on pollinators?

Globally, pollinators are threatened by multiple pressures. Although data is limited, an expert working group of recognised global experts synthesised evidence and identified land use and management as the biggest pressures on pollinators in Europe and globally, followed by chemical pesticides and climate change (Dicks et al., 2021).

Habitat configuration and management affects the scale of pressures on pollinators. A field study of 96 sites across the UK demonstrated that the benefits of higher floral resource availability are heavily affected by the configuration and diversity of habitats and by the use of chemical insecticides (Gillespie et al., 2022). Large scale meta-analyses have also demonstrated the key role of semi-natural habitats in the landscape and their configuration in supporting pollinators and pollination (Dainese et al., 2019; Martin et al., 2019) 

Some insecticides have been demonstrated to be harmful t pollinators (Stanley et al. 2015), however, pressures from pesticides can be reduced through the adoption of IPM and other practices which can control pests, maintain production and reduce the risks to pollinators.

Concerns about pesticides and high costs deter beekeepers from providing pollination services. In addition to wild bees, honeybees are also an important source of pollination services in many areas. Beekeeping in the UK is mostly focused on honey production, due in part to the high costs of disease management and the low returns from paid pollination contracts (Breeze et al., 2017). Concerns over pesticide exposure also deter many beekeepers from providing pollination services to crops (Breeze et al., 2019).

Climate change is distorting crop-pollinator interactions. Analysis of new and historic data demonstrates that rising temperatures are creating mismatches between crop flowering and the emergence of pollinators (Wyver et al., 2023).  Bumble bees, which are among the most important pollinators of UK and global crops (Kleijn et al. 2015), have been shown to fail to track warming climate throughout Europe (Kerr et al. 2015).

What is the status and trends of pollinators and pollination services?

Pollination services are provided by a wide range of wild and managed bee species. Around 70 different species of bees are known or likely to provide pollination services to the UKs four major pollinated crops (apples, strawberries, field beans and oilseed rape – Hutchinson et al., 2021). In many systems wild bees are the most abundant pollinators and often more effective than managed species (Garibaldi et al. 2013, Garratt et al., 2014, 2016; Mateos‐Fierro et al., 2022).

Pollinator diversity has declined across the UK. More diverse communities of pollinators can increase crop productivity and yield compared to systems which rely on only a few species (Woodcock et al., 2021). Modelling of bee and hoverfly occupancy (the area occupied by an individual species) indicates that there are approximately 25% less species in any given 10km area compared to 1980s (Powney et al., 2019).

Pollinator diversity provides insurance against key species declines. Many of the key bee pollinators of crops have complimentary habitat requirements. As a result, diverse pollinator communities improve the resilience of pollination services to shocks which may cause short-term declines in common pollinators species (Senapathi et al., 2021; Hutchinson et al., 2022). 

Pollinator abundance is lower in high-intensity landscapes. Spatial modelling indicates that the relative abundance of key bee guilds are substantially lower in areas such as east Anglia where farming is most intense, despite the prevalence of pollinated arable crops (Gardner et al., 2020).

There is growing evidence that pollination shortfalls are causing economic losses. Numerous studies have demonstrated that inadequate pollination is resulting in economically significant losses in crop yields (Garratt et al., 2021) in different parts of the UK and among global trading partners.

Pollinator monitoring is an important investment. Although we are able to predict relative pollinator populations, we still do not know which species are becoming more or less numerous or which areas are at greatest risk of pollination service deficit. Pollinator monitoring programmes such as UK PoMS are crucial to track the status of populations (O’Connor et al., 2019; Potts et al., 2021). The costs of these schemes are a fraction of the value of pollination services and can also provide vital ecological research infrastructure (Breeze et al., 2021).

What can be done to reverse economically significant pollinator declines?

Agri-environment measures can reduce pollination deficits in high value crops. Many existing agri-environmental measures, such as hedgerows, flower strips and bare earth creation can enhance resources for wild pollinators in both open (Carvell et al., 2022; Tsiolis et al., 2023; Garratt et al., 2023) and semi-enclosed fruit cropping systems (Mateos-Fierro et al., 2023). This can reduce the yield gaps and yield instability caused by inadequate pollination services (Gardner et al., 2021; Bishop et al., 2023).

Agroforestry can support pollinators and pollination services. By diversifying the farmed landscape, silvoarable agroforestry systems can support a greater abundance and diversity of pollinators (Varah et al., 2020; Staton et al., 2022a) and drive economically significant increases in pollination services (Staton et al., 2022b). These benefits can be further enhanced with effective management of floral understories (Staton et al., 2021)

Tree planting targets could greatly increase the effectiveness of agri-environment management. Higher densities of trees and other woody features can enhance the benefits of hedgerow restoration, agroforestry and woodland establishment measures on pollinators (Image et al., 2023).

Research on pollinators has focused on farmer actions, but should consider other scales. The current body of research has heavily focused on short term, farm scale pressures, impacts and responses - despite the importance of other spatial, temporal and institutional scales (Faichnie et al., 2021). This limits our capacity to develop more system wide solutions that can leverage the participation of business and policy actors.

There is support but little co-ordination between private actors on pollinator declines. Several retailers have taken steps to encourage pollinator friendly practices among their suppliers (e.g. Waitrose, Innocent and COOP) but in general, there is little co-ordination between food system actors regarding their impacts on pollinating insects.

Better planning is needed to reap the benefits of pollinator management. The effectiveness of agri-environmental measures at improving pollination services to crops is limited by the spatial placement of the interventions (Image et al., 2022a, 2022b) and the use of high-intensity plant protection products (McKercher et al., 2020). Engaging with farmers directly can raise awareness and effective management of pollinators (Osterman et al., 2021).

Many of the measure that benefit pollinators also support other beneficial insects. There is growing evidence that many of the habitat measures that support pollinators can also enhance biological pest control by insects such as carabid beetles and earwigs (McKercher et al., 2020; Staton et al., 2021; Karp et al., 2018). Pollinator-friendly management therefore has the potential to reduce agricultural dependence on chemical insecticides, lowering the overall costs of farm management and reducing the risks of pest resilience (Zhang et al., 2018).

28 April 2023