Abstract
Pollination is a critical ecosystem service underpinning the productivity of agricultural systems across the world. Wild insect populations provide a substantial contribution to the productivity of many crops and seed set of wild flowers. However, large-scale evidence on species-specific trends among wild pollinators are lacking. Here we show substantial inter-specific variation in pollinator trends, based on occupancy models for 353 wild bee and hoverfly species in Great Britain between 1980 and 2013. Furthermore, we estimate a net loss of over 2.7 million occupied 1 km2 grid cells across all species. Declines in pollinator evenness suggest that losses were concentrated in rare species. In addition, losses linked to specific habitats were identified, with a 55% decline among species associated with uplands. This contrasts with dominant crop pollinators, which increased by 12%, potentially in response agri-environment measures. The general declines highlight a fundamental deterioration in both wider biodiversity and non-crop pollination services.
Highlights
Pollination is a critical ecosystem service underpinning the productivity of agricultural systems across the world
We found widespread variation in the trends of wild pollinators in Britain, with individual species experiencing a range of trajectories between 1980 and 2013 (Fig. 1 and Supplementary Figure 1)
We found similar overall declines for bees (25% decline; 95% credible interval (CI): 21% to 30% decline; n = 139 species) and hoverflies (24% decline; 95% CI: 20% to 28% decline; n = 214), there are marked differences between these two groups in the temporal pattern of declines (Fig. 2 and Supplementary Figure 2)
Summary
Pollination is a critical ecosystem service underpinning the productivity of agricultural systems across the world. Losses linked to specific habitats were identified, with a 55% decline among species associated with uplands. Key threats to pollinators include agricultural intensification ( habitat loss and pesticide use), climate change and the spread of alien species[2,6,7]. Despite their importance, there is a critical absence of robust large-scale, species-specific estimates of distribution change for pollinating insects, in particular bees and hoverflies, which are considered some of the most important pollinators[4,8]. Given that pollination effectiveness and vulnerability to anthropogenic drivers differs between species[13,14], data on species-level trends are essential to understand the impacts of environmental change and the efficacy of conservation actions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
