News Article | May 4, 2017
Dick Potts, who has died aged 77, did more to bridge the gap between conservationists, farmers and the game shooting fraternity than any other figure. He combined his training as a scientist, his background as a farmer’s son and his passion for birds to help save the threatened grey partridge. From small beginnings in a Portakabin on a farm in West Sussex in 1968, Dick developed a long-term study into the ecology of the partridge, one of Britain’s most distinctive farmland birds. Even then, numbers of this attractive gamebird were beginning to fall and Dick was charged with finding out why. Through intensive fieldwork, Dick and his colleagues identified three major reasons for the partridge’s decline. First, the growing use of pesticides was reducing the abundance of the insects on which their chicks feed, leading to lower survival rates. Second, more intensive farming and the consequent reduction in habitat meant there were fewer places to nest. Third, as partridge numbers fell, the relative effects of predation increased. Dick likened this combination of factors to a three-legged stool, noting that if a single leg failed the whole system would collapse. This was pioneering work, and developed into what became known as the Sussex Study – now the longest established survey of farmland ecosystems in Europe. It was the first time that ecologists had looked closely at the man-made habitat of farmland; until then they had focused mainly on natural and semi-natural ecosystems. The work inspired a generations of scientists and led to new methods of conserving farmland birds. Born on the farm belonging to his parents, Eleanor (nee Knox) and Edward Potts, near Richmond, North Yorkshire, Dick took an active interest in local wildlife from early childhood. A key influence on his future career was the hard winter of 1946-47 – the second coldest of the 20th century – and its effect on local birds. On leaving Scorton grammar school, in 1958 he went to Durham University, to study zoology. He stayed at Durham for his PhD, completing his research into the breeding biology of the shag, based on the Farne Islands, in 1966. Having discovered that agricultural pesticides were even affecting the breeding success of seabirds, he determined to find out what harm they might be doing to farmland birds. So in 1968 he joined the Game Conservancy (now the Game and Wildlife Conservation Trust), where he remained for the rest of his formal career. In 1976 Dick was appointed director of research, and moved from Sussex to the trust’s headquarters at Fordingbridge, in Hampshire. In 1992 he rose to become director general, and spent a decade engaged in the controversies over driven grouse shooting, working closely with the RSPB to try to find a resolution to this perennial conflict, before his official retirement in 2002. But like so many passionate conservationists, Dick never really retired. He continued to put his theories into practice on the Duke of Norfolk’s estate near Arundel, West Sussex. As he had predicted, this led to a huge increase in partridge numbers, from just a handful to several hundred breeding pairs. He also devoted several years to writing a volume for the authoritative Collins New Naturalist series. Partridges: Countryside Barometer (2012) drew together a lifetime’s knowledge and experience and, as its title suggests, concluded that when the grey partridge is in trouble, so is all farmland wildlife. This built on his earlier 1986 work, The Partridge: Pesticides, Predation and Conservation, which had won the Wildlife Society’s book of the year award. During his long career he also published more than 100 scientific papers. Dick was a man ahead of his time. Despite the early warning about the harmful effects of agricultural chemicals, flagged up by the US campaigners in the 1960s, the realisation that Britain’s farmland birds were in trouble took decades to be accepted. The eventual realisation that intensive farming often leaves little or no room for wildlife was in no small part down to Dick’s thorough scientific investigation, along with his ability to persuade others of his case. Unlike many others in the game conservation world, he roundly condemned the illegal persecution of hen harriers on grouse moors, and dismissed the widely held but completely erroneous belief that birds of prey are somehow responsible for the reduction in songbird numbers. He always worked closely with farmers, seeing them as the key to reversing the declines in farmland wildlife, and improving the biodiversity of our countryside. His contribution to conservation was widely recognised and won him several major awards, including the Godman-Salvin medal from the British Ornithologists’ Union (BOU) in 1999, and the Country Landowners’ Association award for services to the countryside. During his career he was also chairman of the World Pheasant Association and vice-president of the BOU, and in 2003 was awarded a Leverhulme emeritus fellowship. This funded research on changes into cereal crop biodiversity. On the day of his death he was told that he had won the RSPB gold medal. He is survived by his second wife, Olga Patterson, whom he married in 1988, a son, Gareth, from his first marriage, to Elsie (nee Cooper), which ended in divorce, and a stepson, Martin.
Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: KBBE.2013.1.4-08 | Award Amount: 3.82M | Year: 2014
Many EU and nationally funded research projects in the fields of agriculture and forestry provide excellent results, but the outreach and translation of these results into field practices is limited. The overall aim of VALERIE is to boost the outreach of research by facilitating the integration into innovative field practices. The work in VALERIE consists of three major approaches. (1). Stakeholder-driven approach. Ten case studies set the central stage for the bottom-up approach of the project, aided by highly effective tools of web semantics and ontology. Cases are centred around a specific supply-chain, a farming sector or a landscape. The stakeholder communities (SHC) represent the natural networks engaged in innovation. They drive the process of articulating innovation needs, enabling the retrieval of precisely matching knowledge and solutions, and evaluating their potential in the local context. (2) Theme-driven approach. VALERIE retains six thematic domains that are at the heart of sustainable production and resource use. These six provide the back-bone for structuring the annotation and summarising activities, which in turn will provide a vast body of knowledge accessible via the Communication Facility (CF). (3) Knowledge disclosure. VALERIE will launch a Communication Facility (CF) for the EIP-Networking Facility. The CF supports communication amongst actors in the field and researchers. Next, it injects new knowledge into the innovation process, by enabling users to retrieve highly relevant (tailored-to-needs) information, based on their own vocabularies. In offering tools for communication, as well as content structured for efficient knowledge retrieval, the CF fuses the advantages typical of learning networks and linear modes of knowledge sharing. The CF will be set up, tested and integrated into the EIP-NF platform, as a generic infrastructure for use by fresh stakeholder communities, also beyond the life of the VALERIE project.
Agency: European Commission | Branch: H2020 | Program: RIA | Phase: SFS-02b-2015 | Award Amount: 7.63M | Year: 2016
European crop production is to remain competitive while reducing environmental impacts, requiring development and uptake of effective soil improving cropping systems. The overall aim of SOILCARE is to identify and evaluate promising soil-improving cropping systems and agronomic techniques increasing profitability and sustainability across scales in Europe. A trans-disciplinary approach will be used to evaluate benefits and drawbacks of a new generation of soil improving cropping systems, incorporating all relevant bio-physical, socio-economic and political aspects. Existing information from literature and long term experiments will be analysed to develop a comprehensive methodology for assessing performance of cropping systems at multiple levels. A multi-actor approach will be used to select promising soil-improving cropping systems for scientific evaluation in 16 study sites across Europe covering different pedo-climatic and socio-economic conditions. Implemented cropping systems will be monitored with stakeholder involvement, and will be assessed jointly with scientists. Specific attention will be paid to adoption of soil-improving cropping systems and agronomic techniques within and beyond the study sites. Results from study sites will be up-scaled to the European level to draw general lessons about applicability potentials of soil-improving cropping systems and related profitability and sustainability impacts, including assessing barriers for adoption at that scale. An interactive tool will be developed for end-users to identify and prioritize suitable soil-improving cropping systems anywhere in Europe. Current policies and incentives will be assessed and targeted policy recommendations will be provided. SOILCARE will take an active dissemination approach to achieve impact from local to European level, addressing multiple audiences, to enhance crop production in Europe to remain competitive and sustainable through dedicated soil care.
Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: KBBE.2012.1.2-02 | Award Amount: 3.82M | Year: 2013
The project aims to identify the key semi-natural habitats (SNH), outside and within crops, providing essential ecological services (ES). Vegetation traits will be linked to potential ES provision, case studies will measure actual ES levels and inform models which will show unused opportunities and trade-offs among ES by SNH from habitat to landscape scale. This will be achieved for a range of representative cropping systems and farming intensities in regions dominated by agriculture and matched to the requirements of local and national stakeholders. Surveys will identify key SNH and existing literature will be used to link their vegetation traits to ES provision. ES provision will be measured in existing habitat types (SNH to crop) across economically important cropping systems, farming intensities and four European agro-climatic zones using simple techniques in 16 case studies. A case study is defined by a unique combination of region, crop species, and service. Each case study will concentrate on locally important cropping system and the main ES required. Pollination and pest control have been identified as main ES needed, but also soil fertility, weed control and social services will be considered. The relative socio-economic weight of the studied ecosystem services will be appraised using feedback from national experts using a semi-quantitative method. Data will parameterise spatially explicit models to determine how the vegetation composition, management, shape, area, and placement of SNH in agricultural landscapes affect the distribution of mobile-agent based ecosystem services from farm to landscape level. To investigate synergies and trade-offs in ecological services, multi-criteria analysis will be developed to combine a suite of modules in an integrative modelling framework. Outputs are designed to inform local, national and EU stakeholders on how to improve ES provision from SNH and will include a novel web-based tool.
Firbank L.,University of Leeds |
Bradbury R.B.,RSPB |
McCracken D.I.,Scottish Agricultural College |
Stoate C.,Game and Wildlife Conservation Trust
Agriculture, Ecosystems and Environment | Year: 2013
Here, we review the delivery of ecosystem services from Enclosed Farmland in the UK, and explore how the expected demands for ecosystem services might be met in the future. Most Enclosed Farmland is managed for agriculture; the UK is 60% self-sufficient in foods. Pollinators are in serious decline, but little is known of trends of predators of crop pests. Effects of agriculture on water quality and climate regulation are negative but improving; GHG emissions fell by 20% between 1990 and 2008. Recent declines in numbers of some farmland birds and in plant species richness have been halted, though not reversed. Enclosed Farmland provides considerable leisure and cultural value. Effective delivery of multiple ecosystem services requires improved understanding of how ecosystem services are generated, and of their economics and governance. Food production can be integrated with the delivery of other ecosystem services by promoting a diversity of farming systems and allocating land to different ecosystem services according to its suitability. Approaches include, minimising negative environmental impacts of food production through technology; mitigating environmental harm by managing areas for environmental benefit, from patches within fields to much larger areas; and developing markets and regulations for environmental protection. © 2012 Published by Elsevier B.V.
News Article | March 23, 2016
Creating a three dimensional environment for birds bred for field sports can help many more survive when they are released into the wild, a new study shows. Giving pheasants raised perches in their pens during their first seven weeks helps them grow larger with bigger leg bones, fly higher and grasp, and roost off the ground safe from predators. This makes them less likely to be killed than birds bred without perches. Researchers also discovered the introduction of raised perches helps pheasants develop better spatial awareness and memory. This may enable them to remember where good sources of food could be found, and therefore thrive in the wild. The birds studied lived on a shooting farm in Hampshire, the Middleton Estate, and the research was carried out in partnership with the Game and Wildlife Conservation Trust. They were observed over two seasons. More than 40 million pheasants are released into the UK countryside each year, and around a quarter die because they come into contact with predators. This is thought to be because an intensive rearing environment does not allow the development of essential survival characteristics. Experts involved in the study manipulated the environment of the pheasants in an effort to make it more realistic. This allowed intensively reared individuals to perform a greater range of behaviours and will better prepare them for release into the wild. As part of the study academics had to follow the pheasants around the Hampshire countryside in the dark, wearing night vision googles, to discover where they had roosted. Birds naturally use elevated perches to roost at night as a form of anti-predation behaviour and in the wild, pheasant mothers give calls which draw chicks up to roost on elevated perches. An absence of perches during early development may inhibit individual opportunities for learning and development. The pheasants studied were less likely to die of natural causes in the six months after release into the wild, but differences in mortality were lost over the following breeding season. Dr Joah Madden, from the Centre for Research in Animal Behaviour, one of the researchers on the study, said: "It is economically, ethically and environmentally very wasteful for so many pheasants to die so early on in their life. "Our study shows that even when reared in the absence of their parents and under unnatural conditions you can help pheasants develop physically, behaviourally and cognitively which leaves them less vulnerable and more likely to succeed in the wild. "The pheasants hadn't had the same experience of learning to get higher up to escape foxes and other predators. We gave them opportunities to develop their muscles so they had stronger legs." This research carried out in partnership with the Game and Wildlife Conservation Trust aims to improve the conditions of game bird breeding. The research group at the University has already established pheasant health and survival prospects can be improved through changing their diet. Explore further: Buzzards less likely than humans to kill pheasants, study finds More information: Plastic behavioural, morphological and cognitive traits shaped by early spatial environment have fitness consequences for released pheasants, Royal Society Open Science, rsos.royalsocietypublishing.org/lookup/doi/10.1098/rsos.160008
News Article | January 30, 2015
Is there anything more stupid than the government’s plan to kill grey squirrels? I ask not because I believe – as Animal Aid does – that grey squirrels are harmless. Far from it: they have eliminated red squirrels from most of Britain since their introduction by Victorian landowners, and are now doing the same thing in parts of the continent. By destroying young trees, they also make the establishment of new woodland almost impossible in many places. As someone who believes there should be many more trees in this country, I see that as a problem. A big one. No, I oppose the cull for two reasons. The first is that it’s a total waste of time and money. Here’s what scientists who have studied such programmes have to say: “To date, there has been no successful method developed in the long-term control (nor indeed the eradication) of grey squirrel populations ... a recovery in numbers was found to take place within 10 weeks of intensive culling programs.” You pour the money in and it pours out the other side. The government’s plan to sponsor an “eradication programme” to the tune of £100 per hectare per year is futile; though it will have the effect of transferring even more public money to rural landowners. I doubt you’ll be surprised to hear that the idea was approved by the former environment secretary Owen Paterson, whose primary mission in office appears to have been showering his chums with gold, while ruthlessly cutting any spending that might have delivered wider benefits. This was the man, remember, who almost doubled the subsidy for grouse moors. My second reason for opposing the cull is that there is another way of dealing with grey squirrels, which requires hardly any expense, indeed hardly any human intervention at all. Unlike trapping, shooting or poisoning, it works. It is happening with extreme prejudice in Ireland at the moment. There is a scientific term for this method. Pine martens. Pine martens are predators native to Britain and most of Europe. They are members of the otter, badger and weasel family (the mustelids), that are at home both on the ground and in the trees. They are, to my eye, exceptionally beautiful. They look like sinuous chestnut cats with yellow bibs. Like many predators they turn out to be essential to the survival of healthy living systems. It now seems that many exotic species, like grey squirrels, that appear to present intractable problems do so only because they are moving into depleted ecosystems. They become invasive and destructive because there is nothing left to restrain them. American mink, for example, are a major problem in Europe where there are no otters, proliferating rapidly and wiping out water voles, birds and other species. But when otters, which are highly territorial, move in, they drive the mink out. White-tailed eagles, which have recently been reintroduced to the Hebrides, but once lived throughout Britain, prey heavily on mink and, according to a study in Finland, keep them out of areas they would otherwise occupy. There might be no grey squirrel problem – in fact there might be no grey squirrels here at all – had pine martens not been eliminated across most of their range, primarily by gamekeepers. If you love grey squirrels, look away now, for Ireland has become a bloodbath. The North American rodents that once occcupied the whole island east of the River Shannon are now in full-scale rout, and the reds are pouring into the territory they have abandoned. While until recently the greycoats looked invincible everywhere, in around 20 years the frontier has shifted 100km to the east. At this rate, in another 20 years the last of them will have been driven into the Irish Sea, and Ireland will have been reclaimed by the reds. (No political metaphor is intended.) So what’s going on? Well it now seems that the reason why grey squirrels never got past the Shannon is not that they couldn’t cross the river. They can swim, and there are plenty of places in which they could move through the trees without getting their feet wet. It’s because the far side of the Shannon was pine marten territory. And pine martens love grey squirrels – in the strictly carnal sense. Red squirrels have a simple adaptation to pine martens: they are small and light enough to get to the ends of the branches, where the martens can’t follow. But grey squirrels, which did not co-evolve with these predators, are, by comparison, lumps: slower and heavier than the native species. They are also more terrestrial than the reds – more dependent for their survival on foraging on the woodland floor. Meals on legs, in other words. As people in Ireland have mostly stopped killing pine martens, which are now legally protected, they have begun to recolonise their former ranges. And the grey squirrels appear to have vanished into thin air. You have to read the paper published on this phenomenon last year to believe just how rapid and comprehensive this process has been. But in case you don’t, here are some extracts. “The grey squirrel population has crashed in approximately 9,000 km2 of its former range and the red squirrel is common after an absence of up to 30 years.” “Grey squirrel sightings accounted for less than 8% of animal sightings in [the Irish Midlands], which is remarkably low considering that they are a much less elusive species than either the red squirrel or the pine marten, and are also more commonly associated with human settlements.” The health and weight of grey squirrels in the pine marten zone is “extremely poor,” while squirrels in an area without martens “are thriving”. “This is the first documented evidence of a grey squirrel population retracting, without any human intervention, subsequent to having established itself as an invasive species.” Two aspects of this story jump out at me. The first is the greys’ astonishing speed of retreat. The numbers just don’t add up: the martens simply couldn’t eat that many squirrels. As the paper points out, “it would be unlikely that a low-density pine marten population could impact a high-density grey squirrel population by direct predation alone.” The second is that grey squirrels in the region haunted by pine martens are much thinner than those elsewhere. At first sight this makes no sense: with fewer competitors, you would expect the survivors to be fatter and healthier. So what’s going on? Though the paper doesn’t speculate, there seems to be a likely explanation. The pine martens are creating a “landscape of fear”, rather like the one that some ecologists (though others have now challenged the claim) believe wolves have generated among deer in Yellowstone National Park in the US state of Wyoming. It’s not just that pine martens are eating the squirrels: they are terrifying the living daylights out of them. If grey squirrels have no defences against martens, they must spend much of the time they would otherwise have spent feeding trying to avoid them. They are likely, metaphorically or perhaps literally, to spend so much time looking over their shoulders while they should be foraging during the summer that they don’t accumulate sufficient fat to get through the winter. The pine martens are starving them out. The lesson is obvious – to everyone except the dunderheads administering public policy in Britain. If, as they claim, their aim is to eliminate grey squirrels, rather than to pour money into the laps of the landed gentry, they should abandon the useless programme of trapping, shooting and poisoning, and instead bring back a native predator. While pine martens are once again thriving in parts of Scotland (and, surprise, surprise, these are the places in which red squirrels also survive and grey squirrels are absent), across England and Wales they are functionally extinct. This means that while there are some tiny remnant populations in a few areas (Cumbria, Snowdonia and the North York Moors for example), due to intense persecution by gamekeepers, and others in the past, their genetic base is too narrow to allow them to expand. Re-establishing pine martens means reintroducing them: bringing new genetic stock both to the pockets in which they survive and to places from which they have been eradicated. That is what the Vincent Wildlife Trust, among others, hopes to do. Meanwhile, the Game and Wildlife Conservation Trust, which I see as a greenwashing agency for the shooting industry (how many conservation groups do you know that teach children to use shot guns and run courses on snaring, lamping and trapping?), is campaigning to reduce pine marten populations in Scotland. Yes, reduce. It claims that it wants to do so to protect capercaillies: the giant grouse that also once lived across much of Britain but are now confined to a few glens in Scotland. But there is no evidence that pine martens are implicated in the capercaillie’s decline: in fact the capercaillie is doing best where pine martens are also thriving, and doing worst where the predator continues, illegally, to be persecuted. The Game and Wildlife Conservation Trust’s attitude is typical of the views that have long prevailed amongst shooting interests: all too often estate owners would rather cut their own throats than tolerate the presence of predators, even when those predators are protecting them from massive problems, like grey squirrels or (due to the absence of lynx) exploding roe and sika deer populations. Unfortunately, it is these entrenched interests and attitudes that still dominate government policy. The futile plan to cull grey squirrels was hatched at a symposium of chinless wonders convened by the Prince of Wales and Owen Paterson in one of Charles’s many properties, Dumfries House in Scotland. This meeting took place several months after the Irish study was published. But the British establishment is almost impervious to new thinking and new information, so perhaps it’s unsurprising that this confederacy of dunces decided to pour millions into a futile gesture, rather than to do something useful. I dare say that most of them still regard pine martens as vermin anyway. Like the army and navy in the 18th century, the governance of the countryside is still dominated by titled amateurs, while those with professional knowledge and expertise are frozen out. So perhaps there is a political metaphor here after all. Isn’t it time that these grey and ponderous relics of the Victorian era were pushed out of policy-making, and replaced by bright-eyed and bushy-tailed people who are agile enough to respond to new situations?
Newborn D.,Game and Wildlife Conservation Trust |
Baines D.,Game and Wildlife Conservation Trust
Medical and Veterinary Entomology | Year: 2012
Sheep ticks Ixodes ricinus (Acari: Ixodidae) and tick-borne diseases cause major economic losses in both upland sheep farming and moorland shoots of red grouse Lagopus lagopus scoticus. Sheep were treated with acaricide four times between March and October and double-vaccinated against louping ill virus (LIV), instead of the conventional regime of two acaricide treatments and no vaccinations, on two moors in northern England. Enhanced treatment started at Westerdale Moor in 1995 and at Danby Moor in 2000; the latter had previously represented a spatial control site. From 1992 to 2003, grouse chick condition, tick burdens, reproductive success, shooting bags and LIV seroprevalence were measured. A total of 1297 grouse chicks from 398 broods were examined for ticks. Enhanced acaricide treatment reduced tick burdens by 90%, and LIV seroprevalence decreased in relation to the number of years since treatment began. Breeding success and post-breeding densities of grouse in the current sample area remained unrelated to acaricide treatment, tick burdens or LIV seroprevalence, but 25% and 60% more grouse were shot on Westerdale and Danby, respectively, after treatment enhancement than before. By improving shooting bags, tick management schemes help to maintain the economic viability of grouse moors, which, in turn, provide upland landscape and wildlife benefits. © 2011 The Authors. Medical and Veterinary Entomology © 2011 The Royal Entomological Society.
Aebischer N.J.,Game and Wildlife Conservation Trust |
Ewald J.A.,Game and Wildlife Conservation Trust
Ibis | Year: 2010
The Grey Partridge Perdix perdix is a European Species of Conservation Concern and a priority species under the UK Biodiversity Action Plan. The Game & Wildlife Conservation Trust (GWCT) launched a major programme to help partridge recovery in the UK, built on the GWCT's Partridge Count Scheme (PCS) and including a demonstration site from 2002. We contrast the national picture of no population change since 1999 from BTO monitoring with a doubling of spring pair density on PCS sites. At the demonstration site, where set-aside was used for habitat creation, Grey Partridge breeding density increased six-fold, to 18 pairs/km2, then fell back. The drop coincided with bad weather but also with the disappearance of rotational set-aside when the set-aside rate fell to zero, which halved the amount of brood-rearing habitat. Non-rotational set-aside remained unchanged, as did the amount of nesting habitat that it provided. Grey Partridge density was significantly linked to rotational set-aside, especially wild bird cover, but not to non-rotational set-aside. The demonstration project also showed that, with appropriate precautions, it was possible to shoot over 60% of Red-legged Partridges Alectoris rufa while maintaining Grey Partridge losses below 5%. On PCS sites, the annual change in spring density in recent years differed in relation to neither shooting pressure nor intensity of Red-legged Partridge releasing. Provision of brood-rearing habitats and game cover increased with the latter, and probably counteracts the shooting losses of Grey Partridges on Red-legged Partridge shoots when, as on PCS sites, active measures keep those losses below 20%. Targeted personal advice channelled through the PCS has been fundamental to these successes and must be expanded. © 2010 The Authors. Journal compilation © 2010 British Ornithologists' Union.
Potts G.R.,Game and Wildlife Conservation Trust |
Ewald J.A.,Game and Wildlife Conservation Trust |
Aebischer N.J.,Game and Wildlife Conservation Trust
Journal of Applied Ecology | Year: 2010
There has been a surge of interest in the effects of modern agriculture on biodiversity but studies of farmland flora have lacked continuity and historical context. Here we present the results of 38 years of annual monitoring of the weed flora of cereal crops on the Sussex Downs. This study investigates the long-term changes in abundance of 214 weed species, two subspecies and one forma found in the cereal fields of a 62-km2 area of the Sussex Downs. Species occurrence and weed abundance were recorded annually in June from 1970 to 2005 inclusive. Stubbles were surveyed in 1968, 1971, 2004 and 2005. Annual archaeophytes and perennial natives predominated and the community belonged to the Papaver rhoeas-. Silene noctiflora association (OV16) of the UK National Vegetation Classification. Overall, 97% of fields were treated with herbicides prior to sampling, reducing dicotyledonous weed abundance by 64% and taxon occurrence by 52%. From 1970 to 2005 there was no trend in overall abundance of dicotyledons, although monocotyledons decreased by 13% relative to the early 1970s. Of 66 taxa monitored from 1970 to 2005, 18 increased, 38 rose and fell (or vice versa) and 10 showed no trend. Annuals increased until the early 1980s, when many were not susceptible to herbicides, before levelling off or declining slightly as the efficacy of herbicides expanded. Perennial dicotyledons increased steadily throughout the study. This latter change was due to the loss of traditional leys, not to changes in herbicide efficacy. Ninety-two species of dicotyledons were found on stubbles, with no significant overall change in occurrence from 1968-1971 to 2004-2005. In both stubbles and crops, species uncommon at the start have tended to increase whereas common species have tended to decrease. Combining this study with earlier records, we estimate that 16 weed species have been lost from the study area and 15 gained. Before 1970, the loss rate of archaeophytes and the gain rate of neophytes were both higher than for other species. Most species lost were historically uncommon whereas many of the species gained are now common. Synthesis and applications. The soil seed bank remains sufficient to enable a rapid restoration of the pre-herbicide flora where needed for wildlife conservation purposes, without 'enhancement', i.e. seeding. The means to do this are available through the UK's agri-environment 'in-field measures', but these are very unpopular with farmers. Incentives need to be much improved to ensure the future conservation of the traditional arable flora. © 2009 Game & Wildlife Conservation Trust. Journal compilation © 2009 British Ecological Society.