But the picture brightened markedly after 1990, with a slowdown in local and national biodiversity losses among bees, hoverflies and wild plants.
Professor Bill Kunin, Professor of Ecology in the Faculty, said: "Most observers have been saying that the 1992 Rio Earth Summit targets to slow biodiversity loss by 2010 failed, but what we are seeing is a significant slowing or reversal of the declines for wild plants and their insect pollinators.
"These species are important to us. About a third of our food production, including most of our fruit and vegetables, depends on animal pollination and we know that most crop pollination is done by wild pollinators. Biodiversity is important to ensuring we don't lose that service. Relying on a few species could be risky in a changing environment," he added.
The study, published in the journal Ecology Letters, found a 30 per cent fall in local bumblebee biodiversity in all three countries between the 1950s and the 1980s. However, that decline slowed to an estimated 10 per cent in Britain by 2010, while in Belgium and the Netherlands bumblebee diversity had stabilised.
The picture was better for other wild bees, with an 8 per cent reduction in diversity in the Netherlands and a stable picture in Great Britain turning into significant increases (7 per cent in the Netherlands and 10 per cent in Britain) over the past 20 years.
While these solitary bees continued to decline in Belgium, hoverfly diversity improved there, shifting from stable diversity in the 1980s to significant (20 per cent) increases in recent decades. British wildflower diversity had declined about 20 per cent from the 1950s to the 1980s, but again the declines have ceased in the past 20 years.
Not all groups fared so well. Butterfly diversity continued to fall in all three countries at roughly the same rates as in the past.
Dr Luisa Carvalheiro, lead author on the paper, said: "It is possible that by 1990 the most sensitive species had already gone. However, that's probably not the whole story, as there are still plenty of rare and vulnerable species present in recent records.
"There is a much more encouraging possibility: the conservation work and agri-environment programs paying farmers to encourage biodiversity may be having an effect. We may also be seeing a slowdown of the drivers of decline. The postwar emphasis on getting land into production and on more intensive farming has given way to a more stable situation in which the rate of landscape change has slowed and in which agrichemical excesses are regulated."
Dr Carvalheiro said: "If what we take from the Rio targets is that the investment in conservation gave us no results, then that is a counsel of despair. This study brings a positive message for conservation. But some important groups are undoubtedly still declining, so continued and increased investment in conservation practices is essential for guaranteeing the persistence of a diverse assemblage of species."
Co-author Professor Koos Biesmeijer, who works both at the University of Leeds and Naturalis, said: "This paper builds on a widely-publicised study we published in 2006 that established that the diversity of bees and of wildflowers had declined. Our new work is based on a much bigger dataset and improved analytic methods, and it reveals much more detail about the scale and timing of biodiversity losses.
"However, while we can use biodiversity records to measure changes in the diversity of pollinators, we can't tell what's happening to their overall abundance or to the quality of the pollination services they provide to wildflowers or agricultural crops. To study these issues would require a long-term monitoring programme."
The research team, including scientists from 18 institutions in Europe and the United States, used historical and contemporary records of species' presence held by organizations including the European Invertebrate Survey, Butterfly Conservation, the Bees Wasps and Ants Recording Society, the INBO Research Institute for Nature and Forest in Belgium and the University of Mons, Belgium.
The study is published in Ecology Letters on Wednesday, May 22, 2013. This is the 21st anniversary of the signing of the Convention on Biological Diversity and has been designated by the United Nations as International Day for Biological Diversity.
The research was funded under the European Union Framework Program 7 projects Status and Trends of European Pollinators (STEP) (http://www.step-project.net/) and Securing the Conservation of biodiversity across Administrative Levels and spatial, temporal, and Ecological Scales (SCALES) (www.scales-project.net), with additional support from the UK Insect Pollinators Initiative.
Graham Askew in collaboration with Bangor University, BBSRC (Mar 2017), £477,383
Stephen Muench, BBSRC (Mar 2017), £132,945
Nic Stonehouse, MRC (Mar 2017), £906,341
Bill Kunin, Steve Sait, BBSRC (Mar 2017), £602,831
Adrian Goldman, EU (Mar 2017), £546,576
Sheena Radford, Wellcome Trust (Mar 2017), £1,836,482
Tom Bennett, Royal Society (Mar 2017), £15,000
Jamie Johnston, Royal Society (Mar 2017), £15,000
Beatrice Filippi, Royal Society (Mar 2017), £15,000
Ryan Seipke, BBSRC (Feb 2017), £52,116
Mary O'Connell, BBSRC (Feb 2017), £46,986
Hannah Dugdale, NERC (Feb 2017), £504,138
Anastasia Zhuravleva, EPSRC (Jan 2017), £100,792
Richard Bayliss, Cancer Research UK (Jan 2017), £1,600,000
John Barr, EU (Jan 2017), £339,000
Mark Harris, Royal Society (Jan 2017), £250,000
Alison Dunn, NERC (Jan 2017), £105,000
Alex Breeze, Pancreatic Cancer Research Fund (Jan 2017), £180,000
Alison Dunn, NERC (Dec 2016), £18,000
Lisa Collins, BBSRC (Dec 2016), £1,681,835
Brendan Davies, Leverhulme Trust (Dec 2016), £247,555
Alan Benson, Mark Drinkhill, Ed White, British Heart Foundaion (Dec 2016), £217,223
Adrian Goldman, Royal Society (Dec 2016), £82,999
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Katie Field, Rank Prize Funds (Nov 2016), £20,000
Jessica Kwok, Royal Society (Nov 2016), £14,948
John Ladbury, Cancer Research UK (Oct 2016), £4,250
Miriam Wittmann, Martin Stacey, Edward Vital, Lupus UK
(Oct 2016), £34,010
Valerie Speirs, NC3Rs
(Oct 2016), £90,000
Nicola Stonehouse, Morgan Herod, David Rowlands, BBSRC
(Sep 2016), £436,424
Joseph Cockburn, Wellcome Trust
(Sep 2016), £100,000
John Barr, Public Health England
(Sep 2016), £94,471
Helen Miller, DSM Nutritional Products A/S
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Steven Clapcote, Vitaflo International Ltd
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Juan Fontana Jordan De Urries
, Royal Society
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Jing Li, Sarah Calaghan, Mark Drinkhill, British Heart Foundation
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Sheena Radford, Alison Ashcroft, BBSRC (Sep 2016), £457,216
Patricija Van Oosten-Hawle, An-Jung Chen, David Westhead, NC3Rs
(Sep 2016), £354,456
Glyn Hemsworth, BBSRC (Sep 2016), £1,024,034
David Jayne, Paul Millner, MRC (Aug 2016), £207,860
Sheena Radford, Alison Ashcroft, BBSRC (Aug 2016), £457,215
Patricija Van Oosten-Hawle, Dave Westhead, An-Jung Chen, NC3Rs (Aug 2016), £354,456
Peter Henderson, EU - European Union
EU - European Union
(Jul 2016), £123,897
Adrian Goldman, EU - European Union
(Jul 2016), £116,290
Urwin, Howard Atkinson, NERC
(Jul 2016), £105,053
Eileen Ingham and colleagues in Engineering and M&H, EPSRC (Jul 2016), £3,867,449
Michael Colman, MRC (Jul 2016), £200,956
Tim Benton, Fresca Group Ltd
(Jul 2016), £52,082
Derek Steele, Sarah Calaghan, Chris Peers, BHF (Jul 2016), £819,241
Paul Millner and colleagues in Engineering and M&H, BBSRC (Jul 2016), £129,647
Vas Ponnambalam, Darren Tomlinson, Stephen Wheatcroft, BHF (Jul 2016), £107,359
John Colyer, Christian Teade and colleagues in M&H, Kidney Research Fund UK (Jul 2016), £39,964
Nicola Stonehouse, David Rowlands, World Health Organisation (Jul 2016), £656,545
Alexander Breeze, MRC
(Jul 2016), £403,513
Yoselin Benitez-Alfonso and colleagues in MaPS, Leverhulme Trust (Jul 2016), £353,301
Joan Boyes, Peter Stockley, Roman Tuma, David Westhead, Bloodwise (Jul 2016), £232,960
Edwin Chen, Leuka
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Helen Miller, Hamlet Protein A/S
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Alexander Breeze, Syngenta
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Alan Berry, Wellcome Trust
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Amanda Bretman, Elizabeth Duncan, Leverhulme Trust
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Andrew Macdonald, Neil Ranson, Richard Foster, Yorkshire Kidney Research Fund (Jul 2016), £51,368
Roman Tuma, Sheena Radford, BBSRC
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Adrian Whitehouse, Ian Carr, Worldwide Cancer Research (Jul 2016), £199,738
Paul Milner, Mike McPherson, Lars Jeuken, Darren Tomlinson and colleagues in Engineering & M&H, MRC (Jul 2016), £3,124,568
Helen Miller, Innovate UK (Jun 2016), £3,463,470
Adrian Goldman, Royal Society
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Jim Deuchars, Susan Deuchars, Shaunna Burke, Dunhill Medical Trust (Jun 2016), £86,570
Keith Hamer, Guy Ziv, DEFRA Dept for Env. Food & Rural Affairs
(Jun 2016), £300,122
Richard Bayliss, EU - European Union
(Jun 2016), £373,565
Sheena Radford, Eric Hewitt, Alison Ashcroft, Andrew Wilson, EPSRC (Jun 2016), £458,278
Jamel Mankouri, John Barr, British Lung Foundation
(Jun 2016), £24,000
Zahrah Timsah, Wellcome Trust (Jun 2016), £100,000
Andrew Macdonald, Kidney Research Fund UK
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Edwin Chen, Academy of Medical Sciences
(Jun 2016), £98,110