Wildlife declines are depressingly familiar in Britain and across the world. However, a new study, published this week in the international scientific journal Ecology Letters, provides some much needed good news.
Declines among insect pollinators and the wild plants that they pollinate paper appear to have slowed down markedly in the past 20 years, perhaps in response to conservation efforts.
The new study led by the University of Leeds and the Naturalis Biodiversity Center in the Netherlands assessed how three important groups of pollinators (bees, hoverflies, butterflies) and plants had changed over the past 60 years in three European countries (Great Britain, the Netherlands and Belgium).
Using extensive datasets of species distribution records, including Butterfly Conservation’s Butterflies for the New Millennium recording scheme, the scientists documented widespread declines in species richness among most groups at local, regional and country levels from the 1950s to 1980s. However, from the 1990s onwards, these declines tended to lessen and even, in some cases, to be reversed.
Sadly, however, Britain’s butterflies have not followed this positive trend. Study co-author and Butterfly Conservation scientist, Richard Fox, explained that “In this analysis, the local species richness of British butterflies declined by 10% in between 1950 and 1989. In other words, each 10km grid square lost 10% on average of its butterfly species between 1950-69 and 1970-89. In more recent decades, this decline has continued, with a 13% reduction in butterfly richness between 1970-89 and 1990-2009.”
“British butterflies continued to decline significantly throughout the study, while other groups such as bees and plants fared better in Britain in more recent decades, as did butterflies in the Netherlands. More effort and resources are required to turn around the declines of British butterflies and to restore the lost richness of insect pollinators that make important contributions to human welfare.”
Carvalheiro, L.G., Kunin, W.E., Keil, P., Aguirre-Gutiérrez. J., Ellis, W.N., Fox, R., et al. (2013) Species richness declines and biotic homogenization have slowed down for NW-European pollinators and plants. Ecology Letters, doi: 10.1111/ele.12121