Environmental Research Foundation, August 4, 2006


Hi, Diana-- You probably saw this, but just in case not. --Peter


Pollinator Declines in Europe

Many agricultural crops and natural plant communities depend on pollination by bees and other insects for reproduction. Now, a report by Biesmeijer et al in the 21 Jul 2006 Science suggests that these pollination "services" are on the decline in some parts of the world.

The team pored over nearly 1 million records of bee and hoverfly observations from national databases in Britain and the Netherlands . They divided the countries into 10 km by 10 km cells and then compared pollinator diversity before and after 1980. Their analysis revealed statistically significant declines in bee diversity across both countries, though hoverfly trends were more variable. Interestingly, bee and hoverfly specialists -- species that live in a narrow range of habitats or pollinate only a few species of plants -- have experienced greater relative declines than more generalist species. The team also found that plant species reliant on the declining pollinators have themselves declined relative to other plant species. As noted in an accompanying news story by E. Stokstad, these data suggest a causal link between pollinator and plant declines, but it is not clear which is driving the trend or if both are responding to some other factor. A co-author of the study discussed the possible causes and implications of the trends in a related podcast 11 Megabytes, MP3.