Mountain areas often hold special species communities, and they are high on the list of conservation concern. Global warming and changes in human land use, such as grazing pressure and afforestation, have been suggested to be major threats for biodiversity in the mountain areas, affecting species abundance and causing distribution shifts towards mountaintops. Population shifts towards poles and mountaintops have been documented in several areas, indicating that climate change is one of the key drivers of species’ distribution changes. Despite the high conservation concern, relatively little is known about the population trends of species in mountain areas due to low accessibility and difficult working conditions. Thanks to the recent improvement of bird monitoring schemes around Europe, we can here report a first account of population trends of 44 bird species from four major European mountain regions: Fennoscandia, UK upland, south‐western (Iberia) and south‐central mountains (Alps), covering 12 countries. Overall, the mountain bird species declined significantly (−7%) during 2002–2014, which is similar to the declining rate in common birds in Europe during the same period. Mountain specialists showed a significant −10% decline in population numbers. The slope for mountain generalists was also negative, but not significantly so. The slopes of specialists and generalists did not differ from each other. Fennoscandian and Iberian populations were on average declining, while in United Kingdom and Alps, trends were nonsignificant. Temperature change or migratory behaviour was not significantly associated with regional population trends of species. Alpine habitats are highly vulnerable to climate change, and this is certainly one of the main drivers of mountain bird population trends. However, observed declines can also be partly linked with local land use practices. More efforts should be undertaken to identify the causes of decline and to increase conservation efforts for these populations.

Summary 1.The maintenance or modification of grazing regimes is frequently advocated to deliver conservation targets in pastoral landscapes, but there are few quantitative studies of the effects of grazing on upland birds. This is particularly true with respect to grazing management in agri-environment schemes. 2. Numbers of black grouse Tetrao tetrix and their breeding success were therefore monitored at 20 sites in the north of England from 1996 to 2000. Ten treatment sites included areas where grazing was reduced before and during the study to < 1·1 sheep ha − 1 in summer and < 0·5 sheep ha − 1 in winter. Each was paired with a reference site that held sheep at two (summer) to three times (winter) the density on the experimental sites. The reduced grazing sites ranged from 0·4 to 3·2 km 2 in size and most were part of existing agreements within agri-environment schemes that had been in place for 1-5 years before 1996. 3. Numbers of black grouse males displaying increased by an average of 4·6% (SE = 2·1) year − 1 at the 10 sites with reduced grazing. Displaying male trends differed significantly between treatment and normally grazed reference sites, where numbers declined annually on average by 1·7% (SE = 1·4). 4. Summer black grouse hen densities showed the greatest rate of increase where grazing was restricted on smaller areas of ground (0·4 km 2 ). Declines occurred at sites where the area of restricted grazing exceeded about 1 km 2 . The rates of change in population density, as indicated by numbers of displaying males, peaked in the early years of grazing reduction and then declined after c. 5-7 years. 5. The proportion of females that retained broods during the late chick-rearing period was 54% (SE = 0·06) at sites with reduced grazing, significantly greater than the 32% (SE = 0·06) at normally grazed reference sites. There was no difference in the size of broods between grazing treatments. 6. This study demonstrates that agri-environment schemes, which encourage extensive management of grazing land, can benefit at least some organisms of conservation importance and lead to some recovery of populations. There is a need, however, for further understanding of how such benefits can be maintained at a landscape scale and over the greater time scales involved in vegetation dynamics and bird population processes.

The influence of predators on the distribution, density and dynamics of their prey species has long been of interest to ecologists and wildlife managers. Where the prey population is also utilized by humans, conflicts may arise through competition for a limited resource. Because gamebird shooting in the UK provides employment, recreation and income, the impact of birds of prey on gamebird populations has been the subject of intense debate for many years. Various approaches have been used to assess the impacts that raptors have on gamebird populations. Here we review the applicability and limitations of the methods used and assess the scientific evidence for population-level and economic impacts of raptors on gamebird populations in the UK. Raptors may, in some situations, take large numbers of gamebirds and may be an important proximate cause of mortality, although few studies have addressed the impacts of raptors on either breeding or pre-shooting densities. Two exceptions are studies of Hen Harrier Circus cyaneus , Peregrine Falcon Falco peregrinus predation on Red Grouse Lagopus lagopus scoticus on moorland in Scotland and Sparrowhawk Accipiter nisus predation on Grey Partridge Perdix perdix on farmland in England. Both these studies suggested that raptors could have population-level impacts when their gamebird prey was already at low density. Studies on predation of captively bred gamebirds suggest that numbers taken by raptors at release pens vary considerably and in a few cases raptors have been documented killing relatively large numbers. On the whole, however, it appears that raptors account for a relatively small proportion of mortality among released birds and the impact on subsequent shooting bags is unknown. We summarize important gaps in current knowledge and recommend specific areas for future research.

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