March 18, 2004

scientists respond to UK biodiversity “crisis”

Experts responding to reports in the journal Science identifying alarming trends in the UK of rapidly reducing biodiversity, including the loss of butterfly, bird and plant species.

Lord Robert May, President of the Royal Society and notable ecologist, said:

“More is known about the diversity of plants and animals in Great Britain than anywhere else in the world. Thomas and colleagues have used this knowledge to look at trends in the abundance of British flowering plants, birds and butterflies.

“They found that 28% of our 1,254 native plant species have significantly decreased in abundance in the past 40 years, 54% of the 2001 native bird species over the past 20 years, and 71% of our 58 butterfly species on the same time span.

“These are dismaying trends, especially the differential decline in invertebrates (butterflies) compared with vertebrates (birds). If this pattern holds more generally then estimates of global extinction rates – which are mainly based on birds and mammals – although already alarming, could err on the optimistic side.”

Dr Michael Rands, Director and Chief Executive of BirdLife International, said:

“Sadly, this study provides further evidence that the world is facing another major extinction crisis, induced, for the first time, by unsustainable human activity. Analysis of extensive UK data sets reveal that insects, like birds, mammals and vascular plants, are undergoing major population declines and regional extinctions and provide further evidence that trends in one taxa are good indicators of extinction rates across the broad spectrum of biodiversity.”

Martin Jenkins, co-author of the Global Atlas of Biodiversity, said:

“Insects comprise more than half of all known species and yet, at global level, next to nothing is known of their conservation status. This study shows that, if the United Kingdom is in any way typical, they may be even more threatened overall than far better documented groups such as birds and plants. It incidentally demonstrates the great importance of long-term monitoring and, even more, of so-called “citizen science” – without an army of volunteers each making a seemingly insignificant individual contribution, it would simply not be possible to carry out this kind of analysis.”

Dr Sandy Knapp, The Natural History Museum, London, said:

“More than half the described species of life on Earth are insects, and this sheer numerical dominance at the species level has led many to suggest that the insects would be thus more resilient to extinction at both the population and species level. The incredibly close tracking of plant, bird and butterfly losses in Britain puts paid to that idea – insects are equally at risk of extinction in today’s changing world. This study could only have been done in Britain, as Britain is such a well-studied island. But the lesson and warning is there for all to see – we are poised on the verge of the sixth extinction crisis. Britain, by virtue of its well-known and well-studied biodiversity, is the canary for the rest of the globe.”

Professor Georgina Mace OBE FRS, Director of Science at the Institute of Zoology, said:

“We’ve been accustomed to using bird and mammal data as the standard source from which to estimate global losses of species, despite clear indications that they might not actually represent the situation of other less-well-studied groups. In this paper, we have the first strong quantitative evidence that our butterflies have fared much worse in the UK than either birds or plants. This result should stimulate a call for better sampling across taxa to use for assessments of species losses at global or local scales. According to the results here, we could be seriously underestimating the severity of the problem.”

Dr Juliet Vickery, Head of the Terrestrial Ecology Unit of the British Trust for Ornithology, said:

“Birds and mammals worldwide frequently put the insect world in the shade in terms of their charisma and popular appeal and yet still we struggle to stem the declines of so many of these species. This work has alarming implications – if insects are suffering even more dramatic but virtually unnoticed declines the prospects for understanding why and taking preventative action currently seem very remote.”

Mark Collins, Director of UNEP World Conservation Monitoring Centre, said:

“Evidence of a global extinction crisis has come into stark focus with these important results from a team of top British scientists analysing unparalleled datasets for birds, plants and butterflies in Britain. What is particularly fascinating is that whereas we have tended to look at better-known birds and plants as harbingers of biodiversity decline, butterflies are clearly more sensitive in indicating dangers ahead.

“Since 1983 when we published the fir IUCN Invertebrate Red Data Book , general concerns for the insects that make up more than half the world’s species have gradually moved towards hard evidence. The authors note that the environmental changes that have caused decline of 71% of British butterflies over the past 20 years are the same as those occurring worldwide.

“In the run-up to the international target of 2010 to achieve a significant reduction in the rate of loss of biological diversity, we need studies like this to assess the scale of the problem and to determine the scope of a realistic response. Without doubt, current efforts are falling far short of what will be needed.”

Below Scientists comment on Impact of Nitrogen Deposition on Species Richness of Grasslands as published in the journal Science:

Mark Collins, Director of the UNEP World Conservation Monitoring Centre, said:

“These results are bad news for plants in Britain and bad news for the worldwide partnership working on the Global Strategy for Plant Conservation, recently adopted by the parties to the Convention on Biological Diversity (CBD). The Strategy aims to “halt the current and continuing loss of plant diversity”. A tough job just got tougher. What is good to note, however, is that CBD nations had the good sense at their recent meeting in Kuala Lumpur to adopt nitrogen deposition as an indicator to be tested by all countries and reported through the convention’s Global Biodiversity Outlook. Inorganic nitrogen has now been recognised as a global problem – it’s time to take some serious and coordinated action.”

Martin Jenkins, co-author of the Global Atlas of Biodiversity, said:

“This study clearly shows the wide-ranging and long-term impact that an airborne pollutant can have on biodiversity – something that has proven surprisingly difficult to demonstrate to date. It provides compelling evidence that maintaining – or restoring – healthy and diverse ecosystems will require concerted action at national and international level, and is not something that can be achieved at the purely local scale.”

Professor Georgina Mace OBE FRS, Director of Science at the Institute of Zoology, said:

“This is an extremely important demonstration of the impact that human activities have and will continue to have on the natural world. The massive increase in fixed nitrogen in the environment, a result of our recent agricultural intensification and burning of fossil fuels, is likely to have had a major impact on grassland species richness, and one from which we cannot recover quickly because of stored and cumulative effects. Although the indicators of this effect have been known for some time, this paper confirms and importantly, quantifies the impact. The data here need to be considered in drafting and implementing environmental management and pollution control legislation.”