A new study reveals widespread losses of pollinators in the UK over the past three decades. Based on the areas they occupy, one-third of wild bee and hoverfly species declined between 1980 and 2013, according to the report published today (March 26) in Nature Communications.
The researchers combined species abundance data with a modeling approach to estimate trends in the ranges for 353 species of wild bees and hoverflies. While many species lost ground, 11 percent expanded their range, including bees that pollinate crops such as oilseed rape. Overall, the analysis found that wild bee and hoverfly pollinators no longer occupy a quarter of the area where they were found in 1980, The Guardian reports.
“The declines in Britain can be viewed as a warning about the health of our countryside,” study coauthor Gary Powney of the Centre for Ecology and Hydrology in the UK tells The Guardian. Researchers are concerned about the losses of pollinators for ecological and agricultural reasons.
“Previous studies have described declines in UK butterflies, moths, carabid beetles, bees and hoverflies—this new study confirms that declines in insects are ongoing,” Dave Goulson, a University of Sussex professor who was not involved with the work, tells The Guardian.
Habitat loss and pesticide use in farming are likely major contributors to the observed decreases, The Guardian reports. However, the loss of insects from some parts of northern Britain may be influenced by a warming climate, according to the study’s authors.
The new findings also point to a drop in biodiversity, as some rarer, more-specialized species have lost out while more commonly occurring insects gained in territory, according to the BBC. Paper coauthor Nick Isaac, also of the Centre for Ecology and Hydrology, tells the BBC that this is “particularly bad news if you’re interested in wildlife and in conservation.”
Because the study looked at distribution and not population numbers, the full extent of the losses may not be captured by the reported metrics. “Going from flowery meadows full of bees to intensive agriculture with a few individuals in a road verge does not result in a change in distribution, but of course is a huge change in [numbers],” Roy van Grunsven of the Dutch Butterfly Conservation project tells The Guardian.