Thank you Andrew for sourcing the article below and the lovely photograph (Bombus Humilis on Devil’s Bit Scabious)
This is a very good summary of a research paper recently published in the journal Conservation Evidence. This journal is open access, so if you’d like to read the whole paper you can, just by clicking on the reference. This summary was written for the Bombus Review,which is sent out to Bumblebee conservation Trust members who request to be kept up to date on recent research papers. It was written by Darryl Cox of the BBCT, and we thank him and the Trust for their permission to reproduce it here.
The rapid response of foraging bumblebees Bombus spp. to hay meadow restoration in the Yorkshire Dales and Forest of Bowland, UK
Edmonson et al. in Conservation Evidence (2017) 14, 61-66 *Open-access*
This case study from the North of England assessed how well recently restored hay meadows performed in terms of attracting bumblebees in comparison with pre-established or ‘ancient’ meadows and more modern, agriculturally improved meadows. The meadows under modern management were typical of improved agricultural grasslands which receive applications of inorganic fertiliser and are intensively grazed throughout the year. Ancient meadows were those characterised as receiving little or no fertilizer, receiving one cut per year in late summer and relatively little grazing. Restored meadows were those which had been back into ancient type management process between one and three years prior to the study, usually via the ‘green hay’ seeding method, which involves spreading cuttings from a local established meadow in late summer.
To work out how successful each meadow type was in attracting bumblebees, the researchers utilised the Bumblebee Conservation Trust’s monitoring protocol; BeeWalk. Although in this case, transects were walked on a weekly basis in June and July rather than a monthly basis, and for analysis purposes transects were divided up into 1000m sections, owing to the fact that transects at different sites differed in length. This enabled the team to calculate the number of species per 1000m.
A total of ten different bumblebee species were recorded throughout the project, including the scarce and localised Bilberry bumblebee (Bombus monticola) which was found in both ancient and restored meadows, but absent from any of the modern meadows. There were no significant differences between ancient and newly restored meadows in terms of the number and diversity of bumblebees recorded, while both contained a significantly greater number and array of bumblebees in comparison with the modern meadows.
Recorders also made a note of which flower species or species group each bee was visiting within each habitat. The authors then used this information to formulate a list of the 15 most commonly visited flowers which made up 98% of all flowers visited by bumblebees in the study. Clovers (Trifolium species), Yellow Rattle (Rhinathus minor), Common Knapweed (Centaurea nigra), Common Cat’s-ear (Hypochaeris radicata), Rough Hawkbit (Leontodon hispidus) and Meadow Vetchling (Lathyrus pratensis) all featured prominently as bumblebee favourites. Of all the bumblebee visits recorded, flowers in the ancient meadows accounted for 52.96%, with 32.44% of the visits occurring in the restored meadows and 10.64% taking place in the modern managed meadows. Whilst not measured directly in this study, the authors suggest that the greater coverage and diversity of flowering plants in the ancient and restored meadows is the main contributor to the increase in bumblebee activity across these meadows.
This study represents some nice evidence of the benefits that hay meadow restoration can have on invertebrate conservation, even within the first few years of management, and also the usefulness of the BeeWalk protocol in measuring bumblebee abundance and diversity across different habitat types.