Towards 'crop-pollinating' landscapes: quantifying pollen supply and demand to manage wild pollinators for their benefits to food production

Lead Research Organisation: University of Cambridge
Department Name: Zoology


Three quarters of the world's important crops, or 35% of all food produced by volume, depends on animal pollinators. This includes many fruits, vegetables, nuts and oils. Recently, scientists have found that most crop pollination in the world is carried out by a small group of bee species, called the 'dominant crop pollinators'. In the UK, no more than 20 species are doing most of the work. One is the honey bee, kept by beekeepers. The others are wild species found commonly in farmland.

Yet numbers of wild bee species found in each place are declining. One of the main reasons for this decline is loss of wild flowers in the countryside, which was dramatic in the twentieth century in the UK. In particular, the loss of flowering plants in the pea and bean family, which have protein-rich pollen, is thought to have caused trouble for wild bee species. Bees rely entirely on food from flowers - nectar and pollen - to survive and raise their young. Nectar is a sugar syrup, and provides them energy to fly and grow. Pollen provides most of the protein, a crucial resource for growing larvae.

One way to help pollinators is by planting extra flowers. This has been shown to increase the numbers of dominant crop pollinators, and can even lead to improvements in crop yield. At the moment scientists don't know how much, or what types of pollen wild bees need to survive at different times of year, and have very little idea how much pollen is already supplied by existing landscapes. Some think there are particular times of year, such as early spring or late summer, when pollen is especially limiting, and adding flowers would really help bees.

This research uses very new scientific techniques to quantify the demand for and supply of pollen in farmland. One exciting development is that scientists have just made a library of DNA sequences from all 1,479 of UK native plants. This makes it possible to identify plant species in bee-collected pollen, by putting the pollen into a sequencing machine. It's called DNA metabarcoding. Early results for honey bees show that pollen from trees could be more important at the start of the year than was previously thought. This research will document all the plants that red-tailed and early bumblebee colonies use over at least two years.

A series of experiments with bumblebees in the laboratory will test how much and what kind of pollen are needed to raise individual larvae, or supply a healthy colony. Combining this information with the pollen sources they choose in real landscapes will allow me to accurately calculate pollen demand by these crop-pollinating bumblebees.

To quantify pollen supply in an area of farmland, I will use image processing techniques borrowed from cell biology to measure how many flowers of each type there are through spring, summer and autumn, using photographs. The idea is to build an easy-to-use piece of software to tell farmers exactly what flowers to plant so their farm supports a thriving wild pollinator community that provides reliable pollination to their crops. The software will compare pollen supply with pollen demand on a monthly basis.

Being able to measure pollen supply and demand in an area of farmland will allow scientists to answer a fundamental question central to ongoing debates about pollinators: What currently limits wild pollinator populations? Is available protein (pollen) the main limiting factor, or is it carbohydrate (nectar), nesting sites, overwinter mortality or negative impacts of pesticides or disease? The overall aim of my research is to test the hypothesis that pollen is the limiting factor in agricultural landscapes. If correct, then the best thing we can do for pollinators is plant flowers. If it is wrong, and something else is limiting pollinator numbers or causing declines, then different strategies will be necessary to retain viable communities of hard-working wild pollinators that support food production.

Planned Impact

The main beneficiaries are as follows:
*National governments or government agencies responsible for pollinator conservation (early beneficiaries)
Natural England, the UK Government's nature conservation agency for England, will benefit from this research because it will enable them to monitor and potentially enhance the effectiveness of their recently launched Mid-Tier agri-environment package: the Wild Pollinator and Farm Wildlife Package. The Package focuses largely on flower provision for pollinators, but does not currently take landscape context or existing flower provision into account. The data on pollen dependencies of wild bumblebees (Objectives 1 and 2) and the flower demand model (Objective 4) can be used to improve advice supporting the scheme, and the design of the scheme itself. The automated flower density protocol and flower demand model (Objectives 3 and 4) provide a mechanism for targeting the scheme at farm level. The scientific question of what currently limits wild pollinator populations in farmed landscapes is hugely pertinent to this scheme and other conservation policy around pollinators.
Other national Governments with Pollinator Strategies, including the Welsh and Irish Governments, and the United States Agriculture Department could also benefit from this approach when designing policy interventions for pollinators.
*Farm advisers and agronomists (early beneficiaries)
Farm advisers and agronomists provide advice directly to farmers, including advice on implementing agri-environment schemes and managing natural resources. The decision support tool that advises how to rectify flower deficiencies for core crop pollinators will help them deliver high quality advice. Hutchinsons Ltd, a leading agronomy company in the East of England, has already perceived a market for such a product (see Pathways to Impact). Demand for pollination in agriculture is growing globally, and there is increasing awareness of the need for pollination services as an input. I expect agronomists around the world to increasingly seek information on how to manage wild pollinators for their services.
*Farmers (medium term beneficiaires)
Farmers who take up the Wild Pollinator Package, or plant flowers without incentive, will be able to avoid wasting money planting in areas, or at times of year when existing flower provision is adequate. Growers of insect pollinated crops can expect to benefit from more effective action to manage dominant crop pollinators, increasing the likelihood that their actions will deliver an economic return through enhanced yield or quality of their produce.
*Larger agri-food businesses (medium term beneficiaries)
Supermarkets such as Waitrose and Sainsbury's, and suppliers such as Worldwide Fruit Ltd, have strong interests in protecting pollinators as part of their sustainability strategies. Such companies need simple, straightforward advice on how to manage pollinators for food production. By identifying likely pollen shortfall periods during the year, and establishing whether pollen supply is limiting wild pollinators in agricultural landscapes, this project will provide crucial evidence to support this advice.
*Conservation NGOs (medium term beneficiaries)
Organisations such as the Bumblebee Conservation Trust, and Buglife (and their equivalents around the world) aim to support wild pollinators in all landscapes, and prevent further declines or extinctions. The datasets on pollen resources needed by common bumblebees, and identified likely shortfall periods during the year, will be invaluable to them in shaping their conservation strategies.
*The public (long term beneficiaries)
There is strong public concern about pollinator decline, and many members of the public are motivated to take action. Planting flowers, in the town or the countryside, is a popular response. Outputs of this research will improve the effectiveness of this action, by allowing targeting, and selection of appropriate species.


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Co-authored a paper on the need to retain at least 20% of natural habitat (native vegetation) in agricultural landscapes (Garibaldi et al. 2020).

We have demonstrated that multi-spectral aerial imagery can be used to quantify within-habitat pollinator foraging resources at very fine scales (3cm-7cm), down to the level of individual floral units. This can be used to improve predictions of pollinator numbers, and enables remote monitoring of pollinator conservation measures. This work is publised in the Journal of Environmental Management (Barnsley et al 2022).

Co-authored a review of impacts of road pollution on wild pollinators, and a series of pilot experiments on impacts of this pollution, in collaboration with University of Exeter (Phillips et al. 2021; Phillips et al. 2020).


Project objectives are as follows:
1) Investigate use of pollen sources at bumblebee nests in a real agricultural landscape.
2) Quantify pollen demand per larva for three bumblebee species
3) Develop and ground-truth a protocol for rapid quantification of floral resources
4) Construct a flower demand model that quantifies additional floral resource requirements to support pollination of crops by wild pollinators in a given landscape.

Objective 1:
In 2020, we moved the bumblebee rearing facility established at UEA to the Cambridge Department of Zoology. In 2021, we reared 20 Bombus terrestris colonies from wild-caught queens, and studied their colony growth rates and collected pollen types in a mapped landscape in Norfolk at different distances from a trunk road (NERC EnvEast Studentship). In 2021, we also ran a series of microcolony experiments to measure impacts of heavy metals found on road verges on the reproductive output of Bombus terrestris (NERC EnvEast Studentship). Data from both these studies have been analysed and we will submit two papers for publication in 2023.

During spring and early summer 2019 and 2021 we sampled pollen collected by managed bumblebee colonies (Bombus terrestris) in Berkshire around a soft fruit farm (BBSRC NRP Studentship DTP in partnership with The Earlham Institute). In partnership with the Earlham Institute and UEA, we have developed a PCR-free method for pollen identification from long read sequences, using nanopore sequencing and reverse metagenomics (Peel et al. 2019). Pollen species from 2019 have now been identified using light microscopy, based on a reference collection of plants flowering in the surrounding landscape. This work was presented as a poster at the British Ecological Society Annual Meeting 2020. DNA from all the pollen samples has been extracted and a postgraduate student trained in bioinformatics. Sequencing and analyses are completed and we will submit a paper for publication in 2023.

Data are published by another group that deliver Objective 2 (Moerman et al. 2016), although they used only commercial Bombus terrestris.

Objective 3: With PhD student Sarah Barnsley (NERC Training Grant NE/P010199/1) we demonstrated that multi-spectral aerial and drone imagery can be used to quantify within-habitat pollinator foraging resources at very fine scales (3cm-7cm), down to the level of individual floral units for five nectar-rich plant species. This was presented at the British Ecological Society Annual meeting in December 2019 and has been published in the Journal of Environmental Management (Barnsley et al 2022). A dataset has been published on the NERC EIDC.

Objective 4: We worked with CASE partner Hutchinson's Ltd, to develop an industry-owned decision support tool that recommends management to enhance floral resources in a specific landscape ((NERC Training Grant NE/P010199/1). This is unlikely to be completed in the duration of the grant. The remote sensing methods are not validated beyond an individual farm, so further research will be required.

Barnsley, S. L., Lovett, A. A., & Dicks, L. V. (2022). Mapping nectar-rich pollinator floral resources using airborne multispectral imagery. Journal of Environmental Management, 313, 114942. doi:

Garibaldi, Lucas A., Facundo J. Oddi, Fernando E. Miguez, Ignasi Bartomeus, Michael C. Orr, Esteban G. Jobbágy, Claire Kremen, Lisa A. Schulte, Alice C. Hughes, Camilo Bagnato, Guillermo Abramson, Peter Bridgewater, Dulce Gomez Carella, Sandra Díaz, Lynn V. Dicks, Erle C. Ellis, Matías Goldenberg, Claudia A. Huaylla, Marcelo Kuperman, Harvey Locke, Zia Mehrabi, Fernanda Santibañez, and Chao-Dong Zhu. 2020. 'Working landscapes need at least 20% native habitat', Conservation Letters, 14: e12773.

Moerman, Romain, Nathalie Roger, Roland De Jonghe, Denis Michez, and Maryse Vanderplanck. 2016. 'Interspecific Variation in Bumblebee Performance on Pollen Diet: New Insights for Mitigation Strategies', PLoS ONE, 11: e0168462.

Peel, Ned, Lynn Dicks, Matthew D Clark, Darren Heavens, Lawrence Percival-Alwyn, Chris Cooper, Richard G. Davies, Richard M Leggett, and Douglas W Yu. 2019. 'Semi-quantitative characterisation of mixed pollen samples using MinION sequencing and Reverse Metagenomics (RevMet)', bioRxiv: 551960.

Phillips, Benjamin B., James M. Bullock, Kevin J. Gaston, Karen A. Hudson-Edwards, Meg Bamford, Dave Cruse, Lynn V. Dicks, Carmen Falagan, Claire Wallace, and Juliet L. Osborne. 2021. 'Impacts of multiple pollutants on pollinator activity in road verges', Journal of Applied Ecology, n/a.

Phillips, Benjamin B., Claire Wallace, Bethany R. Roberts, Andrew T. Whitehouse, Kevin J. Gaston, James M. Bullock, Lynn V. Dicks, and Juliet L. Osborne. 2020. 'Enhancing road verges to aid pollinator conservation: A review', Biological Conservation: 108687.
Exploitation Route The findings will inform implementation of the National Pollinator Strategies developed by Defra and the devolved governments. Our work is informing the new Sustainable Farming Incentive for England being developed by Natural England. We are working in partnership with Hutchinson's Ltd and Berry World Group through CASE Studentships (NERC Training Grants NE/P010199/1 and NE/R007845/1, respectively). Through these partnerships, our research is shaped by business and findings will influence business actions.
Sectors Agriculture, Food and Drink,Environment

Description A key output paper (Garibaldi et al. 2020) is cited in a document published by the Convention on Biological Diversity's Subsidiary Body on Scientific, Technical And Technological Advice (SBSTTA), providing background information in support of the draft Post-2020 Global Biodiversity Framework (Convention on Biological Diversity 2021). It is cited to support the following statement: "Other actions [to support the productivity, sustainability and resilience of biodiversity in agricultural and managed ecosystems] could include the conservation or restoration of native habitats within working landscapes of agricultural and other managed ecosystems. A recent study recommended 20 per cent of native habitat to support conservation and ecosystem services." REFERENCES Convention on Biological Diversity. 2021. "Post-2020 Global Biodiversity Framework: Scientific and Technical Information to Support the Review of the Updated Goals And Targets, and Related Indicators and Baselines." In, edited by Technical And Technological Advice (SBSTTA) Subsidiary Body on Scientific. United Nations Environment Programme. Garibaldi, Lucas A., Facundo J. Oddi, Fernando E. Miguez, Ignasi Bartomeus, Michael C. Orr, Esteban G. Jobbágy, Claire Kremen, Lisa A. Schulte, Alice C. Hughes, Camilo Bagnato, Guillermo Abramson, Peter Bridgewater, Dulce Gomez Carella, Sandra Díaz, Lynn V. Dicks, Erle C. Ellis, Matías Goldenberg, Claudia A. Huaylla, Marcelo Kuperman, Harvey Locke, Zia Mehrabi, Fernanda Santibañez, and Chao-Dong Zhu. 2020. 'Working landscapes need at least 20% native habitat', Conservation Letters, n/a: e12773.
First Year Of Impact 2021
Sector Environment
Impact Types Policy & public services

Description GLobal Insect Threat-Response Synthesis (GLiTRS): a comprehensive and predictive assessment of the pattern and consequences of insect declines
Amount £218,018 (GBP)
Funding ID NE/V007173/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 11/2020 
End 11/2024
Description Healthy soil, Healthy food, Healthy people (H3)
Amount £6,144,270 (GBP)
Funding ID BB/V004719 
Organisation University of Sheffield 
Sector Academic/University
Country United Kingdom
Start 01/2021 
End 12/2025
Description Bumblebee conservation research 
Organisation Bumblebee Conservation Trust
Country United Kingdom 
Sector Charity/Non Profit 
PI Contribution Three PhD studentships have been supported by BBCT under the CASE model. Two started in 2022, one is due to start in 2023. Students are doing empirical field research and data analysis, on aspects of bumblebee ecology and conservation, including the potential for competition with honey bees, the role of parasites in bumblebee ecology and the conservation of Bombus sylvarum.
Collaborator Contribution Three PhD studentships have been supported under the CASE model. The BBCT brings datasets, field sites, land managers and partners, and expertise on bumblebee ecology and conservation. Richard Comont, the Head of Science at BBCT is a cosupervisor of the research projects.
Impact No outputs yet.
Start Year 2022
Description Cool Farm Alliance 
Organisation Cool Farm Alliance
Country United Kingdom 
Sector Private 
PI Contribution We are developing the Cool Farm Biodiversity tool, a improvement and assessment tool for farm management, linked to the Conservation evidence database.
Collaborator Contribution The Cool Farm Alliance co-owns and manages the Cool Farm Biodiveristy Tool software that we have developed. It promotes use of the software internationally, through its membership and beyond, and provides technical support and development through partnership with Anthesis Group (a software development company)
Impact Cool Farm Biodiversity tool online software. New Zealand Sustainability Dashboard/
Start Year 2014
Description Earlham Institute 
Organisation Earlham Institute
Country United Kingdom 
Sector Academic/University 
PI Contribution We have a shared PhD student, under the BBSRC Norwich Research Park Doctoral Training Programme. I provide funds to cover the cost of DNA extraction and sequencing services.
Collaborator Contribution Earlham Institute has trained the student in DNA extraction, library preparation, sequencing and bioinformatics, and provides lab space for her to work.
Impact None so far.
Start Year 2020
Description EntoGEM 
Organisation University of Nevada
Country United States 
Sector Academic/University 
PI Contribution The GLiTRS team have built a relational database to store insect population time-series. We are providing a storage location for data generated by the EntoGEM team. Together we will create a global database of insect time-series.
Collaborator Contribution the EntoGEM project aims to create a Global Evidence Map (GEM) for insects. This is a database of studies, created from a systematic literature review, on insect population trends. The EntoGEM team have produced GEMs for two insect orders: Odonata and Lepidoptera. They are now in the process of extracting the data for Lepidoptera, which will be stored in the GLiTRS database. The two teams will work together to co-create (with GLiTRS) a meta-analysis of trends for this group.
Impact none yet
Start Year 2022
Description Status of Insects: An International Research Coordination Network, funded by the US National Science Foundation 
Organisation Insect Research Systems
Country United Kingdom 
Sector Private 
PI Contribution Lynn Dicks is a member of the Steering Group for the Status of Insect RCN, and leads the Working Group on Solutions. In collaboration with the RCN, we wrote a proposal for a Round Table discussion event at the forthcoming International Congress on Conservation Biology. This has been accepted, and will take place July 23-27, 2023, in Kigali, Rwanda. Title: Conservation of small things - how to incorporate insects (and other invertebrates) into the global biodiversity conservation agenda. The format will be six 12-minute presentations, each with 3 minutes for questions, plus a 1.5-hour Round Table discussion chaired by the Symposium Organiser.
Collaborator Contribution RCN is a network of US researchers on insect biodiversity. Members of the RCN organising committee supported our proposal for a Round Table event at a forthcoming international conference, and put forward one speaker.
Impact none yet
Start Year 2022
Title Cool Farm Tool Biodiversity Metric 
Description The Cool Farm Tool is an industry-led environmental decision-support tool used by members of the Cool Farm Alliance ( The current focus is to develop a suite of tools according to the elements of farm-scale sustainability performance assessment identified by the Sustainable Agriculture Initiative Platform ( With additional support from a BESS Programme Knowledge Exchange grant (NE/M000206/1), we have developed a biodiversity module for the Cool Farm Tool. It uses a scoring system for farms to rapidly assess their overall management of biodiversity, based on rigorous, unbiased assessment of evidence for the effectiveness of specific actions (Crowther et al. (in prep for Environmental Modelling and Software). The tool has been integrated into the online Cool Farm Tool by the software company Anthesis Group, funded directly by the Cool Farm Alliance. As part of the SUFICA project (BB/R016429/1) a new module in the Biodiversity metric was created, for farms in the Mediterranean and Semi-Arid environments. This was designed and tested in partnership with farmers from Spain and Chile. 
Type Of Technology Webtool/Application 
Year Produced 2016 
Impact The Cool Farm Biodiversity module has so far been tested by Unilever, the Game and Wildlife Conservation Trust and FarmCare. Ultimately, this software tool will gather data and potentially improve on-farm biodiversity management on thousands of farms in European supply chains. A New Zealand Government-funded project called 'The Sustainability Dashboard' is developing a New Zealand version of the tool. In 2021, the Mediterrean and Semi-Arid version of the Cool Farm Biodiveristy metric it will be used by citrus suppliers to Tesco, to report their biodiversity management. This step is being overseen by AM Fresh Ltd. 
Description Ask A Scientist Live 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact 28th May Ask A Scientist Live online event organised by Scientists for Extinction Rebellion: Agrecology - can we feed the world without destroying it. Questions and Answers, with a panel of experts. Total viewing figures reported 04 June 2020 - 21,300, via Facebook, Instragram, Twitter and YouTube. Write up can be found here:
Year(s) Of Engagement Activity 2020
Description Cambridge BioBlitz 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Guided walk to look at solitary bees in the Cambridge Botanic Garden, as part of the Cambridge Bioblitz. (September bee and wasp walk). Records added to i-record.
Year(s) Of Engagement Activity 2020
Description Darwin's Birthday Debate 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact A public talk in the Natural History Museum, on the role of nature-based solutions in tackling insect decline. Sparked debate about sustainable food production. Attend by >100, including museum staff.
Year(s) Of Engagement Activity 2020
Description Defra Environmental Land Management Ecology and Ecosystem Services expert panel 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact Lynn Dicks appointed as a Member of Defra Environmental Land Management Ecology and Ecosystem Services expert panel, to inform the design and development of the Environmental Land Management schemes.
Year(s) Of Engagement Activity 2022,2023
Description Evidence to Science and Technology Committee (Lords) 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact Gave oral evidence to the House of Lords Science and Technology Committee considering Nature Based Solutions for Climate Change on Tuesday 7th September 2021; focus on the effects of agricultural practices.
Year(s) Of Engagement Activity 2021
Description Keynote talk Natural Resources Wales Internal Evidence Conference 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact Keynote talk give to the conference "Evidence into Policy, Strategy and Delivery". Talk title: The diversity of methods to synthesize knowledge (and how to select the right one). The audience was ~ 150 staff, including the Chief Executive of Natural Resources Wales. This sparked questions and discussions about methods of knowledge synthesis, the Conservaiton Evidence database and the MAGICKS decision support tool.
Year(s) Of Engagement Activity 2022
Description Swedish Board of Agriculture seminar 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact Presentation at a seminar on competition between wild pollinators and honey bees, organised by the Swedish Board of Agriculture. Audience was Swedish civil servants and Swedish Government funded researchers.
Year(s) Of Engagement Activity 2020