Many insect pollinator species are disappearing from areas of Great Britain, a new study has found.
The research, led by the Centre for Ecology & Hydrology, measured the presence of 353 wild bee and hoverfly species across the country, from 1980 to 2013. It showed one third of species experienced declines in terms of areas in which they were found, while one tenth increased. For the remainder of species, their distribution was either stable or the trend was inconclusive.
A positive but unexpected finding of the study was the increase in key bee species responsible for pollinating flowering crops, such as oil-seed rape. This could be in response to the large increases of mass-flowering crops grown during the study period and government-subsidised schemes that encourage farmers to plant more of the wildflowers they feed on.
The research, published in the journal Nature Communications, also showed that on average, the geographic range of bee and hoverfly species declined by a quarter. This is equivalent to a net loss of 11 species from each 1km square.
Overall losses were more notable for pollinator species found in northern Britain. This may be a result of climate change, with species that prefer cooler temperatures reducing their geographical spread in response to less climatically suitable landscapes.
Dr Gary Powney of the Centre for Ecology & Hydrology, who led the research, says: “We used cutting-edge statistical methods to analyse a vast number of species observations, revealing widespread differences in distribution change across pollinating insects. There is no one single cause for these differences, but habitat loss is a likely key driver of the declines.
“While the increase in key crop pollinators is good news, they are still a relatively small group of species. Therefore, with species having declined overall, it would be risky to rely on this group to support the long-term food security for our country. If anything happens to them in the future there will be fewer other species to ‘step up’ and fulfil the essential role of crop pollination.
He adds: “Non-crop pollinators are also vital for a healthy countryside rich in biodiversity; not only because of their crucial role in pollinating wildflo
wers, but as a key food resource for other wildlife. Wildflowers and pollinators rely on each other for survival. Losses in either are a major cause for concern when we consider the health and beauty of our natural environment.”
Species that have declined include Panurgus banksianus (Large Shaggy Bee), right Picture: Steven Falk
Dr Claire Carvell of the Centre for Ecology & Hydrology, a co-author of the study, points out there are multiple environmental pressures leading to changing patterns of occurrence in bees and hoverflies across the country.
She says: “There is an urgent need for more robust data on the patterns and causes of pollinator declines. While this analysis sends us a warning, the findings support previous studies suggesting that conservation actions, such as wildlife-friendly farming and gardening, can have a lasting, positive impact on wild pollinators in rural and urban landscapes. However, these need further refining to benefit a wider range of species.”
Dr Carvell adds: “In addition to recording species sightings, more standardised monitoring of pollinator numbers is required at a national level and a new UK Pollinator Monitoring Scheme has been set up to do just this.”
Over 700,000 records were analysed for this study. Most were collected by expert naturalists in the Bees, Wasps and Ants Recording Society (BWARS) and the UK Hoverfly Recording Scheme, in more than 19,000 1km by 1km squares across Great Britain. It’s thought to be the first study of its kind, since there have been no previous large-scale, long-term, species-specific estimates of distribution change for pollinating insects in Britain.
Mike Edwards of BWARS said: “All important studies of animal population trends, such as this latest research, rely entirely on the wildlife recorders who go out and record sightings of different species in their area. Therefore, we would encourage more people to take part in wildlife recording, so we can increase our understanding of how wildlife is responding to environmental change.”
Members of the public who wish to get involved in recording insect pollinators in their local area can find out more on the UK Pollinator Monitoring Scheme website.
Notes to editors
- Bombus ruderarius (Red-shanked Carder Bee): Formerly a widespread bumblebee species found in much of England and Wales, and parts of Scotland. Our results estimate that this species has declined by 42 per cent between 1980 and 2013.
- Lasioglossum parvulum (Smooth-gastered Furrow Bee). Widely found in southern Britain, where it tends to be found visiting Blackthorn flowers in the spring. Our results suggest this species has declined by 40 per cent between 1980 and 2013.
- Panurgus banksianus (Large Shaggy Bee): Found in coastal regions in Southern England and Wales, where it can be found nesting along the edges of footpaths. Our results suggest this species has declined by 54 per cent between 1980 and 2013.
- Andrena cineraria (Ashy Mining Bee): Currently a widespread species found in large parts of England and Wales. An important crop pollinator, particularly for oil-seed rape. Our results suggest this species has shown over a five-fold increase between 1980 and 2013.
- Colletes hederae (Ivy Bee): Colonised mainland Britain in 2001 where it was recorded in Dorset. Since then it has been spreading rapidly. Our results suggest this species has increased by 16 per cent per year since arrival. Interestingly, this species is relatively new to science, only being described in 1993.
- Lasioglossum pauxillum (Lobe-spurred Furrow Bee): Formally a rare species that has seen widespread increases, our results suggest this species has shown over a five-fold increase between 1980 and 2013. This species is now considered an important crop pollinator in England.
Photographs available on request.
Gary D. Powney, Claire Carvell, Mike Edwards, Roger K. A. Morris, Helen E. Roy, Ben A. Woodcock and Nick J. B. Isaac. 2019. Widespread losses of pollinating insects in Britain. Nature Communications. DOI: 10.1038/s41467-019-08974-9
For interview requests or further information, please contact Simon Williams, Media Relations Officer at the Centre for Ecology & Hydrology, via 07920 295384 or email firstname.lastname@example.org
This research was possible thanks to schemes funded by a number of different organisations - the UK Joint Nature Conservation Committee, the Natural Environment Research Council, the Biotechnology and Biological Sciences Research Council, Defra, the Scottish Government and the Welsh Government.
About the Centre for Ecology & Hydrology
The Centre for Ecology & Hydrology (CEH) is a centre of excellence for integrated research into land and freshwater ecosystems and their interaction with the atmosphere. CEH is a Natural Environment Research Council (NERC) research institute, part of UK Research and Innovation (UKRI). The Centre’s independent, impartial science addresses major societal and environmental challenges: how to protect and enhance the environment and the benefits it provides; how to build resilience to environmental hazards; and how to manage environmental change. Its core expertise is in environmental monitoring, measuring and modelling.
The Bees Wasps and Ants Recording Society (BWARS) is a voluntary group of naturalists who have a particular interest in this group of insects. BWARS co-ordinates the collection, validation and verification of information submitted by its members and other contributors to the BWARS database. This data is then made available for use in studies of these insects, such as this one. BWARS does not endorse the outcome of any interpretation made from its data.
About the UK Hoverfly Recording Scheme
The UK Hoverfly Recording Scheme has been compiling records since 1976 and is one of the largest invertebrate datasets after Lepidoptera and Odonata. The data have been supplied by over 8,000 people, with contributors ranging from photographers to taxonomic specialists. It now holds in excess of 1 million records and is growing at around 65,000-70,000 records per year.
About the UK Pollinator Monitoring Scheme (PoMS)
The UK Pollinator Monitoring Scheme (PoMS) is co-ordinated by the Centre for Ecology & Hydrology (CEH). It is jointly funded by Defra, the Welsh and Scottish Governments, JNCC and project partners, including CEH, the Bumblebee Conservation Trust, Butterfly Conservation, British Trust for Ornithology, Hymettus, the University of Reading and University of Leeds. PoMS aims to provide much-needed data on the state of the UK’s insect pollinators, especially wild bees and hoverflies, and the role they fulfil in supporting farming and wildlife.