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Managing predation on ground-nesting birds Many ground-nesting farmland bird species have decreased in numbers drastically in recent years mainly due to loss and fragmentation of their habitats. Therefore, management of declining species has often focussed on protection and restoration of their habitats, but this is not always enough. High rates of nest predation may also threaten bird populations and both lethal and non-lethal predator control has therefore been employed to decrease the predation pressure on threatened groundnesting birds. Lethal predator control is often used to reduce nest predation, but it is problematic since it must be continuous as otherwise culled predators might be replaced through immigration from nearby areas, and there may be negative attitudes towards lethal predator control among the general public. Several non-lethal techniques have been proposed and implemented as management tools for threatened species, but few have been properly evaluated. We evaluated the use of nest exclosures as a non-lethal means of reducing nest predation on ground-nesting waders. We tested exclosures on two common and widespread shorebirds: lapwing and redshank. In both species, hatching success was much higher for protected than for unprotected nests. In redshanks, however, mortality increased on incubating birds in protected nests while no such effect was found in lapwings. Therefore, caution should be exercised in the use of nest exclosures on redshanks or species with similar incubation behaviour. However, nest exclosures should be considered as a management tool for shorebirds that leave their nest early when approached by a predator.