Are sterols landscape limiting nutrients for wild bees in the UK?

Mapping pollen phytosterols through space and time in the UK landscape, and elucidating the importance of phytosterols as essential nutrients for wild bee diversity

Close up of a bee Macropis europaea on a yellow flower covered in pollen
Team Lead

Prof. Phil Stevenson (PI)

Team 

Dr Hauke Koch (Researcher Co-Investigator)

Pollen sterols are essential nutrients for bees (e.g., for membrane fluidity, hormones and physiological functions). Bee larval development is highly sensitive to specific dietary pollen sterols.

Our recent work shows striking variations of pollen sterol chemistry across plant taxa and not all plant pollen contains all the same sterols.

There is also close association between pollen and bee sterol chemistry that strongly suggests bees use the specific sterols in the pollen they collect.

Bees cannot synthesise or modify sterols so in terms of sterols bees are what they eat. We do not currently know whether these differences reflect differences in sterol tolerances or differences in sterol requirements.

This project is testing this for the first time and aims to provide a mechanistic basis for bee population and community dynamics, and a valuable tool in conserving diverse bee communities and the ecosystem services they provide. We will undertake the first comprehensive assessment of sterol nutrients in pollen of UK plants and in UK wild bees.

Using these data, we will identify key plant species that can support the greatest diversity of wild bee species.

These data will be integrated into landscape scale models of pollen resources to inform pollen sterol provision in the UK. Landscape-scale modelling based on measurements of plant distributions will be used to estimate the capacity of the landscape to support pollinator populations, taking a major step forward from existing assessments on carbohydrates in nectar.

We will match these data with assessments of wild bee species to determine how important specific pollen sterols are for specific bees.

We will conduct the first ever assessment of how sterols influence development in wild bees to understand fully the potential cost of sterol limitations in the landscape, how dependent bee species are on specific sterols and how this influences specialisation in wild bees. 

Prof Bill Kunin (Leeds University)
Prof Geraldine A Wright (Hope Professor of Zoology - University of Oxford). 
Prof Jane Memmott (Bristol University). 
Nichola Hutchinson (PlantLife)

NERC (UKRI) Standard mode