The diversity of bees and of the flowers they pollinate, has declined significantly in Britain and the Netherlands over the last 25 years according to research led by the University of Leeds and published in Science this Friday (21 July 2006). The paper is the first evidence of a widespread decline in bee diversity.
Concerns have been raised for years about the loss of pollination services, but until recently most of the evidence has been restricted to a few key species or a few focal sites. To test for more general declines, an international team of researchers from three UK universities (Leeds, Reading and York) and from the Netherlands and Germany compiled biodiversity records for 100s of sites, and found that bee diversity fell in almost 80% of them. Many bee species are declining or have become extinct in the UK [for detailed examples, see the attached case studies].
Lead author, Dr Koos Biesmeijer from the University of Leeds said: "We were shocked by decline in plants as well as bees. If this pattern is replicated elsewhere, the 'pollinator services' we take for granted could be at risk. And with it the future for the plants we enjoy in our countryside."
Pollinators are essential for the reproduction of many wild flowers and crops. Co-author Simon Potts (of the University of Reading) said: "The economic value of pollination worldwide is thought to be between 20 and 50 billion each year."
The team examined pollinator and plant data, collected by professional and volunteer researchers and naturalists in Britain and the Netherlands, comparing records from before and after 1980. The results showed bee diversity had declined consistently in both countries, whereas the diversity of hoverflies (another group of pollinating insects) stayed roughly constant in Britain, but increased in the Netherlands.
Loss of bee diversity in itself might not be too worrying, so long as other surviving insect pollinators are si
Contact: Hannah Love
University of Leeds