Journal of Insect Conservation

, Volume 17, Issue 6, pp 1181–1189

Pollinators and pollination of oilseed rape crops (Brassica napus L.) in Ireland: ecological and economic incentives for pollinator conservation


DOI: 10.1007/s10841-013-9599-z

Cite this article as:
Stanley, D.A., Gunning, D. & Stout, J.C. J Insect Conserv (2013) 17: 1181. doi:10.1007/s10841-013-9599-z


Pollinators are beneficial for many wild and crop plants. As a mass-flowering crop, oilseed rape has received much focus in terms of its pollination requirements but despite a threefold increase in area of cultivation of this crop in Ireland over the past 5 years, little is known about its pollination here. We surveyed the flower visiting insects found in commercial winter oilseed rape fields and evaluated the importance of different pollinator groups, investigated the contribution of insect pollination to oilseed rape seed production, and estimated the economic value of insect pollination to the crop at a national level. Our data showed that winter oilseed rape is visited by a wide variety of insect species, including the honeybee, bumblebees, solitary bees, and hoverflies. The honeybee, Eristalis hoverflies and bumblebees (especially Bombus sensu stricto and B. lapidarius) were the best pollinators of winter oilseed rape based on the number of pollen grains they carry, visitation rates per flower and their relative abundance per field. Exclusion of pollinators resulted in a 27 % decrease in the number of seeds produced, and a 30 % decrease in seed weight per pod in winter crops, with comparable values from a spring oilseed rape field also. The economic value of insect pollination to winter oilseed rape was estimated as €2.6 million per annum, while the contribution to spring oilseed rape was €1.3 million, resulting in an overall value of €3.9 million per annum. We can suggest the appropriate conservation and management of both honeybees and wild pollinators in agricultural areas to ensure continued provision of pollination services to oilseed rape, as a decrease in insect numbers has the potential to negatively influence crop yields.


Valuation of ecosystem servicesBombusBioenergy cropsOilseed cropsPollinator dependent cropsAgroecologyCrop pollinationAgricultureMass-flowering crops

Supplementary material

10841_2013_9599_MOESM1_ESM.doc (515 kb)
Supplementary material 1 (DOC 515 kb)

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Dara A. Stanley
    • 1
  • Daryl Gunning
    • 1
  • Jane C. Stout
    • 1
  1. 1.Botany Department, School of Natural Sciences and Trinity Centre for Biodiversity ResearchTrinity CollegeDublin 2Ireland