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Since 1968, Turtle Doves Streptopelia turtur in Britain have declined in number by 70% and in breeding range by at least 25%. This study was undertaken during the 1998–2000 breeding seasons at two sites in East Anglia to examine habitat use and foraging ecology. Home ranges of radiotagged Turtle Doves were 0.3–1130 ha in size and contained more woodland than expected from availability. Radiotagged birds undertook foraging trips of up to 10 km. Turtle Doves were recorded feeding primarily at ‘man‐made’ sites (i.e. spilt grain, animal feed and grain stores) and were only infrequently recorded feeding at ‘natural’ sites. Diet analysis showed that wheat and rape seed averaged 61% of the seeds eaten by Turtle Doves. This contrasts with a study undertaken in Britain in the 1960s, when the seeds of wild plants (weeds) constituted over 90% of those eaten, with wheat and rape seeds making up only 5%. The current arrangements for set‐aside and agri‐environmental schemes provide a framework for the establishment and maintenance of weed‐rich areas on farmland as a source of wild food.

Summary1. There is increasing evidence to link major declines in skylark populations in Britain to agricultural intensi®cation. However, whether causal mechanisms identi®ed through localized studies can be generalized to the national scale remains unknown. The abundance of breeding skylarks was determined by surveying singing males in over 600 randomly selected 1-km squares throughout Britain, in which skylarks recorded were assigned to homogeneous habitat patches. A more intensive survey of skylarks was carried out on lowland farmland sites in England. Singing males were assigned to speci®c crop types, and data on crop height and ®eld boundary features were recorded. 2. Skylark occupancy (presence/absence) and density where birds were present (i.e. omitting zero counts) were analysed in relation to habitat type, habitat diversity and time of year, using generalized linear modelling. 3. Set-aside, moorland and winter cereals had high rates of skylark occupancy at the national scale. Set-aside had consistently high rates of occupancy and high densities across the breeding season at dierent spatial scales. Apart from set-aside, there was little dierence in density between habitats in the early half (March to mid-May) of the breeding season. In the later half of the breeding season (midMay to July), density declined signi®cantly on winter cereals, which showed signi®-cantly lower density than a number of habitats at this time, including spring cereals, legumes and moorland. 4. Within lowland farmland, there were signi®cant eects of crop height on skylark occupancy, with crops of greater than 30 cm in height being occupied at relatively low rates. Winter cereals reached this height signi®cantly earlier in the breeding season than a number of other crops, including spring cereals and legumes. 5. Skylark density increased with increasing habitat diversity across the whole sample of 1-km squares and in lowland 1-km squares in England. However, within the lowland farmland plots in England, skylark density showed a signi®cant decrease with increasing habitat diversity. These con¯icting results suggest that crop type rather than habitat diversity per se is important. 6. The eects of vegetation height on skylark abundance support the hypothesis that increases in winter cereal, and simultaneous loss of spring cereal, have had an adverse eect on skylark populations by reducing the number of breeding attempts made per year. These results support ®ndings from smaller scale studies showing the generality of these habitat eects at dierent spatial scales. The extent of the British skylark population associated with agricultural land suggests that sympathetic changes in farming practice are likely to provide the best mechanism for improving the status of this species. The inclusion of options, such as spring cereal or fallow land (an equivalent to set-aside), in agri-environment schemes is likely to bene®t skylarks breeding on farmland by providing suitable nesting habitat throughout the breeding season. In addition, reductions in...

The migratory European Turtle Dove Streptopelia turtur has undergone a 69% decline in population size and a 25% contraction in breeding range in Britain over the last 30 years. An investigation of the breeding ecology of this summer visitor was undertaken in 1998-2000 at two study sites in East Anglia, England. The only previous study of Turtle Dove reproduction in Britain provided pre-decline data for comparison with the current situation in a modern agricultural environment. Territory sizes ranged from 1.91 to 3.08 ha, were established in areas with scrub, hedges and woodland and contained less cropped land than expected from its availability. The majority of nests were sited 1-3 m above ground level within thorny bushes, particularly Hawthorn Crataegus monogyna . Nests found by radiotelemetry were significantly higher above ground level and were found in greater numbers than expected in woodland and coniferous trees than those found by cold searching, which were lower and found predominantly in hedges and thorny bushes. Turtle Dove nest success rate averaged 53% during incubation and 65% during the nestling stage, so that only 35% of nests successfully produced young. A comparison with data collected during the 1960s showed that Turtle Doves today have a shorter breeding season and consequently produce about half the number of clutches and young per pair than formerly. A simple simulation model suggested that the reduction in productivity alone would lead to a population decline of 17% per annum. This study suggests that the recovery of Turtle Doves in Britain is dependent upon the provision and sympathetic management of nesting and foraging habitats. The current arrangements for set-aside and agri-environmental schemes provide the framework for delivering these requirements.

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Agri‐environment schemes could play a key role in the reversal of farmland bird declines. The effectiveness of the Arable Stewardship Pilot Scheme for delivering farmland birds was tested in a replicated, farm‐scale field trial, in two lowland farmland regions of England. Changes in numbers of birds over five years were compared between control and scheme farms. In East Anglia, productivity of Grey Partridges Perdix perdix was significantly higher on scheme than on control farms, although such an effect was not seen in the West Midlands where the species was rarer. At the field scale, wintering granivorous passerines and Skylarks Alauda arvensis responded to stewardship habitats (options) such as stubble and wild bird cover designed specifically to benefit them. However, at the farm scale, winter bird counts were higher on scheme than control farms only in the West Midlands, and not in East Anglia where the availability of set‐aside and features managed for game in the wider landscape was higher. In the absence of other high‐quality habitat, arable options are effective at providing good quality habitat, but the amount needed to exert an influence at the bird population level remains uncertain.