2026/04/03 by David Baines, Nicholas J. Aebischer · 1 voice
Environmental Science · #Avian ecology and behavior #Wildlife Ecology and Conservation #Rangeland and Wildlife Management
paper · doi:10.1080/00063657.2026.2685164
Capsule Upper Teesdale in northern England supported 1,764 pairs of Eurasian Curlews (95% CL: 1,486–2,145), representing approximately 3% of the UK population; successful breeding and repeat counts indicated recent stable numbers.Aims To estimate breeding numbers by extrapolating from habitat-specific densities, nesting success (including three other wader species) from camera traps and population status from repeat counts.Method Birds were surveyed using transect-based methods in six habitat types within 114 1 km × 1 km grid squares. Linear densities estimated from transects in each habitat were converted into areal densities by comparing transect results with those from block surveys within the same grid squares. Habitat-specific densities were multiplied by habitat availability in the study area to give habitat-specific totals, which were summed to estimate total population size. Clutch survival was monitored using camera traps. Population status was assessed from repeat surveys approximately 10 years apart.Results All but one surveyed square supported Eurasian Curlews, with densities highest in rough grazing and grass-moor habitats at mid-elevations. Twice as many Eurasian Curlews occurred on blanket bog managed by burning and cutting than on unmanaged bog. Abundance from whole-square searches (block surveys) was 29% higher than from transect surveys in the same squares. Summed habitat-specific totals gave 1,764 pairs. Estimated clutch survival of Eurasian Curlews was 0.51, averaging 0.71 for four wader species combined. The most frequent clutch predators detected were Eurasian Badgers Meles meles, Stoats Mustela erminea and Sheep Ovis aries. Eurasian Curlews fledged 1.0 chick per pair, double the number needed to sustain numbers. Repeat surveys indicated that breeding numbers were stable in recent years at both scales.Conclusions High densities and high breeding success of Eurasian Curlews occurred within connected open-ground upland habitats within designated protected landscapes, where licensed culling of predators and management of blanket bog by gamekeepers to produce Red Grouse Lagopus scotica for recreational shooting, together with wildlife-friendly farming, were widely practised.