Abstract
Machair is a grassland habitat that supports nationally rare species including the bumblebee species Bombus distinguendus and Bombus muscorum. Changes in land management practices have resulted in a loss of floral diversity in some areas, reducing the availability of bumblebee foraging resources. In order to determine the most effective way of increasing forage plant availability on degraded machair, a restoration trial was established in western Scotland and comprised four seed mixes and a fallow treatment. Treatments were monitored over 3 years in order to compare the relative abundance of bumblebees and their forage plants. Two mixes contained wildflower species; one mix is currently used to create bird and bee foraging habitat on nature reserves and the fourth is a commercially available grass mix. There was little variation in inflorescence and bumblebee abundance between treatments early on but marked differences emerged later in the season in all 3 years. By the end of the monitoring period, the wildflower treatments contained between four and eighteen times more inflorescences than other treatment types. Similar trends were observed in bumblebee abundances. Some of the rarest bumblebee species exist primarily in areas that have largely escaped agricultural intensification. In these areas it is important that habitat management is specifically targeted and translated into appropriate agri-environment schemes. We suggest that the most effective method for restoring bumblebee forage plants on machair is to sow wildflower-rich seed mixes and this should be combined with late cutting and winter grazing practices to maintain sward diversity over time.
Similar content being viewed by others
References
Angus S (2001) The Outer Hebrides moor and machair. The White Horse Press, Cambridge
Bäckman J-PC, Tiainen J (2002) Habitat quality of field margins in a Finnish farmland area for bumblebees (Hymenoptera: Bombus and Psithyrus). Agric Ecosyst Environ 89:53–68
Beaumont D, Housden S (2009) The RSPB Scotland strategy for machair management with particular reference to birds and achievements of the great yellow bumblebee project. Glasg nat 25 supplement: machair conservation, successes and challenges, pp 11–16
Benton T (2006) Bumblebees—the natural history and identification of the species found in Britain. Harper Collins, London
Carreck NL, Williams IH (2002) Food for insect pollinators on farmland: insect visits to flowers and annual seed mixtures. J Insect Conserv 6:13–23
Carreck NL, Williams IH, Oakley JN (1999) Enhancing farmland for insect pollinators using flower mixtures. Aspect Appl Biol 54:101–108
Carvell C (2002) Habitat use and conservation of bumblebees (Bombus spp.) under different grassland management regimes. Biol Conserv 103:33–49
Carvell C, Meek WR, Pywell RF, Goulson D, Nowakowski M (2007) Comparing the efficacy of agri-environment schemes to enhance bumble bee abundance and diversity on arable field margins. J Appl Ecol 44:29–40
Chamberlain DE, Fuller RJ, Bunce RGH, Duckworth JC, Shrubb M (2000) Changes in the abundance of farmland birds in relation to the timing of agricultural intensification in England and Wales. J Appl Ecol 37:771–788
Charman T (2007) Ecology and conservation genetics of Bombus distinguendus, the Great Yellow Bumblebee. PhD thesis, University of Cambridge
Coulson SJ, Bullock JM, Stevenson MJ, Pywell RF (2001) Colonisation of grassland by sown species: dispersal versus microsite limitation in response to management. J Appl Ecol 38:201–216
Goulson D (2003) Bumblebees—behaviour and ecology, 1st edn. Oxford University Press, Oxford
Goulson D, Darvill B (2004) Niche overlap and diet breadth in bumblebees; are rare species more specialized in their choice of flowers? Apidologie 35:55–63
Goulson D, Hanley ME, Darvill B, Ellis JE, Knight ME (2005) Causes of rarity in bumblebees. Biol Conserv 122:1–8
Goulson D, Hanley ME, Darvill B, Ellis JS (2006) Biotope associations and the decline of bumblebees (Bombus spp.). J Insect Conserv 10:95–103
Goulson D, Lye GC, Darvill B (2008a) Decline and conservation of bumblebees. Annu Rev Entomol 53:191–208
Goulson D, Lye GC, Darvill B (2008b) Diet breadth, coexistence and rarity in bumblebees. Biodivers Conserv 17:3269–3288
Hanley ME, Franco M, Pichon S, Darvill B, Goulson D (2008) Breeding system, pollinator choice and variation in pollen quality in British herbaceous plants. Funct Ecol 22:592–598
Hansom JD, Angus S (2005) Machair nan Eilean Siar (Machair of the Western Isles). Scott Geogr J 121:404–412
Jackson DB, Green RE (2000) The importance of the introduced hedgehog (Erinaceus europeus) as a predator of the eggs of waders (Charadrii) on machair in South Uist, Scotland. Biol Conserv 93:333–348
Joint Nature Conservation Committee (2007) Second report by the UK under Article 17 on the implementation of the Habitats Directive from January 2001 to December 2006. JNCC, Peterborough. Available from: www.jncc.gov.uk/article17
Kalamees R, Zobel M (2002) The role of seed bank in gap regeneration in a calcareous grassland community. Ecology 83:1017–1025
Kells AR, Goulson D (2003) Preferred nesting sites of bumblebee queens (Hymenoptera: Apidae) in agroecosystems in the UK. Biol Conserv 109:165–174
Kells AR, Holland JM, Goulson D (2001) The value of uncropped field margins for bumblebees. J Insect Conserv 5:283–291
Kent M, Dargie T, Reid C (2003) The management and conservation of machair vegetation. Bot J Scotl 55:161–176
Love J (2003) Machair—Scotland’s living landscapes. Scottish Natural Heritage, Battleby
Lye GC, Park K, Osborne J, Holland J, Goulson D (2009) Assessing the value of Rural Stewardship Schemes for providing foraging resources and nesting habitat for bumblebee queens (Hymenoptera: Apidae). Biol Conserv 142:2023–2032
Mänd M, Mänd R, Williams IH (2002) Bumblebees in the agricultural landscape of Estonia. Agric Ecosyst Environ 89:69–76
Muller S, Dutoit T, Alard D, Grévilliot F (1998) Restoration and rehabilitation of species-rich grassland ecosystems in France: a review. Restor Ecol 6:94–101
Osborne JL, Martin AP, Shortall CR, Todd AD, Goulson D, Knight ME, Hale RJ, Sanderson RA (2008) Quantifying and comparing bumblebee nest densities in gardens and countryside habitats. J Appl Ecol 45:784–792
Owen NW, Kent M, Dale MP (2001) Spatial and temporal variability in seed dynamics of machair sand dune plant communities, the Outer Hebrides, Scotland. J Biogeogr 28:565–588
Pollard E (1977) A method for assessing changes in abundance of butterflies. Biol Conserv 12:115–134
Potts SG, Woodcock BA, Roberts SPM, Tscheulin T, Pilgrim ES, Brown VK, Tallowin JR (2009) Enhancing pollinator biodiversity in intensive grasslands. J Appl Ecol 46:369–379
Pywell RF, Bullock JM, Tallowin JB, Walker KJ, Warman EA, Masters G (2007) Enhancing diversity of species-poor grasslands: an experimental assessment of multiple constraints. J Appl Ecol 44:81–94
R Development Core Team (2009) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna. ISBN: 3-900051-07-0. http://www.R-project.org
Redpath N (2010) Restoration and management of wildflower-rich machair for the conservation of bumblebees. PhD thesis, University of Stirling
Redpath N, Osgathorpe LM, Park K, Goulson D (2010) Crofting and bumblebee conservation: the impact of land management practices on bumblebee populations in northwest Scotland. Biol Conserv 143:492–500
Ritchie W (1967) The machair of South Uist. Scott Geogr J 83:161–173
Roberts HW, Kerr DH, Seaton D (1959) The machair grasslands of the Hebrides. Grass Forage Sci 14:223–228
Scottish Government (2010) http://www.scotland.gov.uk/Topics/farmingrural/SRDP/RuralPriorities/Packages/Machair. Accessed 10 Oct 2010
UK Biodiversity Action Pan (UKBAP) (2010) http://www.ukbap.org.uk. Accessed 4 Jan 2010
Waters J, Darvill B, Lye GC, Goulson D (2011) Niche differentiation of a cryptic bumblebee complex in the Western Isles of Scotland. Insect Conserv Diver 4:46–52
Westphal C, Steffan-Dewenter I, Tscharntke T (2009) Mass flowering oil seed rape improves early colony growth but not sexual reproduction of bumblebees. J Appl Ecol 46:187–193
Wilkinson NI, Wilson JR (2010) Breeding ecology of Twite Carduelis flavirostris in a crofting landscape. Bird Study 57:142–155
Wilson JR (1978) Agricultural influences on waders nesting on the South Uist machair. Bird Study 25:198–206
Wilson JD, Boyle J, Jackson DB, Lowe B, Wilkinson NI (2007) Effect of cereal harvesting method on a recent population decline of Corn Buntings Emberiza calandra on the western Isles of Scotland. Bird Study 54:362–370
Zuur AF, Ieno EN, Walker NJ, Savaliey AA, Smith GM (2009) Mixed effects models and extensions in ecology with R. Springer, New York
Acknowledgments
We thank Scottish Natural Heritage, the Bumblebee Conservation Trust, the University of Stirling and the Royal Society for the Protection of Birds for funding this research. We would also like to extend our thanks to Mike and Val Peacock and the staff and volunteers of RSPB Oronsay for assisting with the implementation and ongoing maintenance of this trial.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Redpath-Downing, N.A., Beaumont, D., Park, K. et al. Restoration and management of machair grassland for the conservation of bumblebees. J Insect Conserv 17, 491–502 (2013). https://doi.org/10.1007/s10841-012-9532-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10841-012-9532-x