Cereal fields are central to balancing food production and environmental health in the face of climate change. Within them, invertebrates provide key ecosystem services. Using 42 years of monitoring data collected in southern England, we investigated the sensitivity and resilience of invertebrates in cereal fields to extreme weather events and examined the effect of long-term changes in temperature, rainfall and pesticide use on invertebrate abundance. Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae. The average abundance of Delphacidae, Cryptophagidae and Mycetophilidae increased in both hot/dry and cold/wet years relative to other years. The abundance of all 10 groups usually returned to their long-term trend within a year after the extreme event. For five of them, sensitivity to cold/wet events was lowest (translating into higher abundances) at locations with a westerly aspect. Some long-term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change.

In 1995, the UK Government designated the Grey Partridge Perdix perdix as a priority species under its Biodiversity Action Plan (BAP). The Game Conservancy Trust (GCT), nominated as lead partner for the species, launched a programme to help Grey Partridge recovery by (1) raising awareness among the shooting and farming communities, (2) encouraging land managers and local BAP groups to conserve Partridges by setting numerical targets and offering feedback from counts on how to increase numbers, and (3) motivating by example by setting up a site demonstrating management techniques and the increase in Partridge abundance that ensues. Building on past research, we quantify the amount of habitat management required to achieve the BAP targets of halting the decline and achieving population recovery. Using three major GCT databases, (1) the National Gamebag Census, which collates data on shooting bags and gamebird releasing in the UK, (2) the Partridge Count Scheme, which monitors national Partridge density and reproduction, and (3) the Sussex Study, which monitors local Partridge population dynamics over 37 years, we emphasize the importance of good breeding success for increasing densities, review the evidence that management can be successful and evaluate the impact of shooting on Grey Partridge conservation.

Summary1. 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. 2. 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-km 2 area of the Sussex Downs. 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. 6. Perennial dicotyledons increased steadily throughout the study. This latter change was due to the loss of traditional leys, not to changes in herbicide efficacy. 7. 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. 8. 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. 9. 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.

Summary 1.Factual information is key to resolving conflicts between raptor conservation and gamebird management, especially when the conservation status of one of the species involved is threatened. The grey partridge Perdix perdix is a UK Biodiversity Action Plan species because of a marked decline in abundance caused by agricultural intensification. Recently, the number of raptors present on farmland and the commercial shooting of red-legged partridges Alectoris rufa have both increased. To inform conservation action, the relative impacts of these two factors on grey partridge populations urgently require quantification. 2. On our study site areas of low density of grey partridges coincided with areas of high raptor density. However, these areas were managed intensively for shooting and for two areas that suffered local partridge extinction, the 3-year average percentage of partridges shot exceeded 50%. 3. Grey partridge mortality to raptors between autumn and spring lay between 9·5% of autumn density (assumes losses to raptors occurred before shooting) and 15% of post-shooting density (if all losses to raptors were post-shooting). A deterministic model suggested that this rate of loss would reduce the equilibrium density of spring pairs by 11-26% relative to a situation without raptors. In comparison, shooting losses across the study area amounted to 35-39% of autumn density, more than double the losses to raptor predation, with a predicted reduction of 68-85% in equilibrium density of spring pairs. 4. Synthesis and applications. Shooting based on large-scale releases of red-legged partridges acts in a density-independent manner and can lead to local grey partridge extinction. Removing the grey partridge from the UK quarry list would be counterproductive, as most action to boost wild grey partridge densities is carried out by enthusiasts with shooting as the incentive. However, it is imperative that managers of intensive shoots based on gamebird release adopt measures to reduce shooting pressure on wild grey partridges at low density. These include training shooters to distinguish between grey and red-legged partridges and implementing a warning system (whistle) to alert the gun line when birds of the non-target species are approaching. Such voluntary measures are effective in addressing overshooting, which has greater implications for grey partridge conservation than raptor predation.

A questionnaire survey of land owners, managers and gamekeepers was conducted in order to assess the distribution of mountain hares in Scotland, assess their current management, collate numbers harvested in 2006-07 and estimate distribution change by comparing with similar data collected in 1995-96. The land area covered by returned questionnaires was 71098km 2 (90% of Scotland). Mountain hares were reported as present on 34359km 2 (48%) and absent from 36739km 2 (52%). Mountain hare presence was strongly associated with heather moorland managed for red grouse shooting. Moorland managed for driven grouse shooting had the highest percentage area of mountain hare presence (median 64%) followed by moorland managed for walked-up grouse shooting (median 9%) and moorland with no grouse shooting (median 0%). Approximately 25000 mountain hares were harvested in 2006-07. Based on the estimated UK population in 1995 of 350000 (range Ϯ50%), this represents around 7% of the population (range 5-14%). Reasons given by respondents for harvesting hares were tick control (50%), sport (40%) and forestry or crop protection (10%). Comparison of the estates surveyed in both 2006-07 and 1995-96 (a total area of 20462km 2 ) indicated no net gain or loss in hare distribution. Furthermore, there was no evidence that levels of harvest had reduced the range of mountain hares in this area. It is not possible to comment on any distribution change *Correspondence author. †Present address: Scottish Natural Heritage, Caspian House, Clydebank Business Park, Clydebank, G81 2NR, UK. ‡This work was published after the untimely death of Simon, who spent many happy hours on Scottish moorlands with family and friends. He is missed by all who worked with him and benefitted from his strong and balanced views on upland conservation. outside this area (58737km 2 ). Similarly, as no data were collected on abundance, it is not possible to draw conclusions on changes in density. Regular monitoring of mountain hare distribution within Scotland is required to identify any distribution changes. Measures of abundance throughout the range are necessary to estimate the population size, investigate the relationship between harvest intensity and changes in abundance and further assess the conservation status of this UK Biodiversity Action Plan species.