- UK wide biodiversity loss will lead to lower resilience of ecosystem functions such as pollination to future perturbations.
- BESS has developed a simple approach that enables farmers to measure and improve how they support biodiversity and ecosystem services.
- BESS research has informed the development of new agri-environment schemes for England that aim to support key pollinator species.
- It is important to consider both cost and effectiveness when considering farm management options for conserving pollinators.
- Biodiverse urban meadow plantings benefit both people and wildlife.
'Insect pollination helps to provide one in every three mouthfuls of our food…'
'8 out of 10 wild plants in Britain depend on insect pollination…'
'Britain has lost 97% of its flower-rich grassland since the 1940’s…'
Headlines like these have stimulated pollinator recovery efforts worldwide, including the National Pollinator Strategy in the UK, but policy makers, land managers and wider society need better evidence and tools to support decision making.
The implications of pollinator decline
The Wessex BESS consortium found there has been a net decline in pollinating insects in Great Britain (see research paper). Currently, most crop pollination in Europe is carried out by just a few species that are not particularly threatened. However, the loss in diversity amongst the wider pollinating community means fewer species to smooth out the effects of fluctuations in population sizes, or to ‘step in’ to fulfil the same role when currently dominant species are impacted. The weakening of this ‘insurance’ capacity provided by biodiversity is particularly important given the uncertain future associated with the need for better food security, climate change and the squeeze on the countryside from urban expansion, all of which could lead to declines in the currently dominant species and insufficient pollination for crops and wild plants.
How can growers best support pollinators?
Making informed decisions
The Cool Farm Tool, developed by BESS, aims to help growers make more informed decisions to reduce their environmental impact. There is a specific output for ‘beneficial insects’, so farmers can see how their actions would be expected to affect pollinators and natural enemies, and can make it an environmental objective to support them. The Cool Farm Alliance includes multinational food suppliers and the approach can be scaled up to whole supply chains.
Development of agri-environment schemes
Work into a new Countryside Stewardship scheme assessed which key bee species the scheme should concentrate on, what was limiting populations of these species and what agri-environment schemes could do that would be sufficient to support them. Providing flower–rich habitat on 2 % of farmed land and 1 km of flowering hedgerow per 100 ha can supply these species with enough pollen to feed their larvae (at low estimates of pollen demand). Importantly, this research also highlights the assumptions and uncertainty involved when designing such schemes (see research paper).
The cost-effectiveness of conservation options
While agri-environment schemes are effective at supporting biodiversity, it is still not clear whether they support production-related ecosystem services in a way that could make them cost effective (see paper). This issue was tackled by BESS researcher Zoë Austin and colleagues in a survey of the perceptions of farmers who were following the Conservation Grade environmentally sensitive farming protocol. Options that were perceived as most effective for pollinators, such as improving the floristic diversity of field headlands, were not the most efficient because of their high cost. Actions to improve hedgerow management were most efficient, despite being perceived as less effective for pollinators. There are many farmland conservation actions that are low cost to farmers and could be applied voluntarily, without monetary incentives (see paper). These include creating uncultivated margins around arable fields and nest boxes for solitary bees.
Pollinators in urban areas
Greenspace in urban areas also has an important role to play in supporting pollinators and provides an opportunity for large numbers of people to have contact with and benefit from biodiversity. Currently, a high proportion of greenspace within urban areas is managed as close-mown amenity grassland with low biodiversity value. Transforming some of this grassland to annual and perennial meadows supports pollinators and other beneficial invertebrates throughout the year (see Urban Grassland policy and practice note).
F3UES Consortium researchers worked with Local Authorities and residents to create a variety of urban meadows in Bedford and Luton. Using photos of different planting options for urban perennial meadows increased visitors' appreciation of the greenspace. When photos of different planting options were compared meadows were preferred to mown grassland or herbaceous borders. More diverse meadows were also preferred, demonstrating a win-win situation for people and wildlife (see paper).
Useful publications from BESS researchers
What is causing the decline in pollinating insects? A Living With Environmental Change policy and practice note
Spatial targeting brings new opportunities for agi-environment schemes A Living With Environmental Change policy and practice note
Managing farmed landscapes for pollinating insects A Living With Environmental Change policy and practice note
Habitat creation and management for pollinators by Marek Nowakowski and Richard Pywell, Centre for Ecology and Hydrology