12 13Land use change and agricultural intensification have greatly reduced the area of natural and semi-14 natural habitats throughout the developed world. Populations in small areas of remaining habitat 15 can experience increased rates of predation which can threaten population sustainability, 16particularly if the surrounding landscape is inhospitable to prey and predators. Excluding predators 17 to reduce impacts of predation can be a short-term solution but is often not feasible or desirable. 18Consequently, there is growing interest in identifying landscape-scale habitat management 19 techniques that could be used to reduce rates of predation on species of concern, for example 20 through altering predator distribution and activity. In Europe, lowland wet grasslands have 21 become increasingly fragmented, and populations of waders in these fragments are subject to

1. Wetland ecosystems throughout the world are threatened by drainage and intensification of agriculture. Consequently, many wetland species of conservation concern are now restricted to fewer and smaller sites, and maintaining these species often requires intensive habitat management. 2. In Western Europe, breeding wader populations have declined severely as a result of wetland degradation, but very high levels of predation on eggs and chicks are now preventing population recovery. Wet grassland management for breeding waders has focussed on providing suitable nesting habitats, but the potential for management of landscape features to influence predation rates is largely unknown. 3. Using a 7-year study of breeding lapwing, Vanellus vanellus, and redshank, Tringa totanus, we first identify features that influence nest predation, and then use this information to compare the magnitude of change in nest predation rates that could potentially result from future landscape management scenarios. 4. As lapwing nest predation rates are higher (a) in fields further from patches of tall vegetation, (b) close (<50 m) to field edges in wet fields, (c) further from field edges in dry fields and (d) in areas of low lapwing nesting density, we modelled a series of realistic scenarios in which the area of tall vegetation and the extent and distribution of surface water were varied across the reserve, in order to quantify the magnitude of change in nest predation rate that could potentially have been achieved through management. 5. Modelled scenarios of changes in surface water and area of tall vegetation indicated that reduced surface flooding combined with removal of tall vegetation could result in significant increases in lapwing nest predation rates in areas with low nesting densities and nests in field centres. By contrast a ~20% reduction in nest predation, corresponding to ~100 more chicks hatching per year, is predicted in scenarios with expansion of tall vegetation in areas with high lapwing nest density and nests close to field edges. 6. Synthesis and applications: These management scenarios suggest that, for breeding waders in wet grassland landscapes, creating areas of tall vegetation and concentrating surface flooding (to encourage high nesting densities and influence nesting distribution) can potentially help to reduce the unsustainably high levels of nest predation that are preventing population recovery

Conservation management of landscapes often targets species of conservation concern, but this can have repercussions for other components of the food web which may, in turn, indirectly influence the target species. In Western Europe, many lowland wet grasslands are managed to encourage declining breeding wader populations but the benefits of creating habitat conditions that attract waders are often limited by increased predation rates. As predator activity may be influenced by the relative availability of different prey sources, we investigate the influence of habitat management for waders on the distribution and activity of the small mammal prey of mammalian predators. Livestock grazing to create the short sward structure that attracts breeding waders on wet grasslands results in areas of tall, dense vegetation being largely restricted to verge areas outwith fields. Through both ink tracking tunnels and field‐sign searches, we found small mammal activity to be almost entirely restricted to swards of > 20 cm height and > 80% ground‐level cover which, in this landscape, is only found in verges and field edges. The creation of extensive areas of short grass to attract breeding waders may therefore be substantially reducing the abundance of mammal prey for the predators that are limiting wader productivity on many sites. Using this information to plan small mammal habitats within these landscapes may be a means of reducing the predation pressure on breeding waders, and there is an urgent need to establish whether predation rates on wader nests and chicks are lower when small mammals are abundant.

Ground‐nesting species are vulnerable to a wide range of predators and often experience very high levels of nest predation. Strategies to reduce nest vulnerability can include concealing nests in vegetation and/or nesting in locations in which nests and eggs are camouflaged and less easy for predators to locate. These strategies could have important implications for the distribution of ground‐nesting species and the success rates of nests in areas with differing vegetation structure. However, the factors influencing the success of nest concealment and camouflage strategies in ground‐nesting species are complex. Here we explore the effects of local vegetation structure and extent of nest concealment on nest predation rates in a range of ground‐nesting, sympatric wader species with differing nest concealment strategies (open‐nest species: Oystercatcher Haematopus ostralegus, Golden Plover Pluvialis apricaria and Whimbrel Numenius phaeopus; concealed‐nest species: Black‐tailed Godwit Limosa limosa, Redshank Tringa totanus and Snipe Gallinago gallinago) in south Iceland, in landscapes that comprise substantial variability in vegetation structure at a range of scales. We monitored 469 nests of these six wader species in 2015 and 2016 and ~40% of these nests were predated. Nest predation rates were similar for open‐nest and concealed‐nest species and did not vary with vegetation structure in the surrounding landscape, but nest‐concealing species were ~10% more likely to have nests predated when they were poorly concealed, and the frequency of poorly concealed nests was higher in colder conditions at the start of the breeding season. For concealed‐nest species, the reduced capacity to hide nests in colder conditions is likely to reflect low rates of vegetation growth in such conditions. The ongoing trend for warmer springs at subarctic latitudes could result in more rapid vegetation growth, with consequent increases in the success rates of early nests of concealed‐nest species. Temperature‐related effects on nest concealment from predators could thus be an important mechanism through which climate change affecting vegetation could have population‐level impacts on breeding birds at higher latitudes.

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Birds exhibit various forms of anti-predator behaviours to avoid reproductive failure, with mobbing—observation, approach and usually harassment of a predator—being one of the most commonly observed. Here, we investigate patterns of temporal variation in the mobbing response exhibited by a precocial species, the northern lapwing (Vanellus vanellus). We test whether brood age and self-reliance, or the perceived risk posed by various predators, affect mobbing response of lapwings. We quantified aggressive interactions between lapwings and their natural avian predators and used generalized additive models to test how timing and predator species identity are related to the mobbing response of lapwings. Lapwings diversified mobbing response within the breeding season and depending on predator species. Raven Corvus corax, hooded crow Corvus cornix and harriers evoked the strongest response, while common buzzard Buteo buteo, white stork Ciconia ciconia, black-headed gull Chroicocephalus ridibundus and rook Corvus frugilegus were less frequently attacked. Lapwings increased their mobbing response against raven, common buzzard, white stork and rook throughout the breeding season, while defence against hooded crow, harriers and black-headed gull did not exhibit clear temporal patterns. Mobbing behaviour of lapwings apparently constitutes a flexible anti-predator strategy. The anti-predator response depends on predator species, which may suggest that lapwings distinguish between predator types and match mobbing response to the perceived hazard at different stages of the breeding cycle. We conclude that a single species may exhibit various patterns of temporal variation in anti-predator defence, which may correspond with various hypotheses derived from parental investment theory.Electronic supplementary materialThe online version of this article (doi:10.1007/s10211-016-0236-1) contains supplementary material, which is available to authorized users.

Capsule: Northern Lapwing Vanellus vanellus avoid nesting close to small woodland patches but nest predation rates do not vary with distance to woodland patches, either because risky areas are avoided or perceived nest predation risk doesn't reflect actual risk. Aims: To explore the effects of woodland patches in wet grassland landscapes on nest distribution and success of Lapwings. Methods: We quantified the effect of woodland patches on the distribution and outcome of Lapwing nests across four wet grassland sites by mapping nest distribution and monitoring nest outcomes. Results: Lapwing nested significantly further from woods than expected by chance. Neither nest predation rates nor the probability of predation occurring at night (thus primarily mammalian predators) or day (primarily avian predators) varied in relation to distance from woodland patches. Conclusions: High levels of nest and chick predation in wet grassland landscapes limit the capacity for breeding wader populations to be self-sustaining. Consequently, identifying manageable landscape features that influence predation rates is an important focus of conservation research. Lapwing avoid breeding close to woodland but, as nest predation rates don't vary with distance from woodland patches, their removal may increase the area of suitable nesting habitat but is unlikely to substantially influence productivity. References Aebischer, N.J. 1999. Multi-way comparisons and generalized linear models of nest success: extensions of the Mayfield method. Bird Study 46: 22-31.

Impacts of generalist predators on declining prey populations are a major conservation issue, but management of this situation is constrained by limited knowledge of the factors influencing predator distribution and activity. In many declining populations of ground-nesting waders, high levels of nest and chick predation are preventing population recovery. Red foxes, Vulpes vulpes, are the main predator but their primary prey is small mammals. On wet grasslands managed for breeding waders, small mammals are concentrated in tall vegetation outside of fields, and nests closer to these patches are less likely to be predated. To assess whether these patterns result from fox attraction to small mammals, and thus the potential for management of tall vegetation to influence nest predation rates, we quantify seasonal and spatial variation in fox and small mammal activity in relation to tall vegetation patches. Across wet grassland sites, tall vegetation patches of any size (> 0.05 ha) supported small mammals and small mammal activity increased throughout the wader breeding season, while the use of fox track plots within fields declined seasonally. Although within field fox track plot use did not vary with distance to tall vegetation, over the 1064 nights of trail camera recording, foxes were seen in areas with tall vegetation on 13 nights compared with short vegetation on only two nights. These findings suggest that lower predation rates of Lapwing, Vanellus vanellus, nests close to tall vegetation could reflect fox attraction to areas with small mammal activity, but any such effects would primarily operate later in the breeding season, and may therefore primarily influence late nests and chicks. Renards, campagnols, et échassiers : les prédateurs les plus actifs dans les prairies humides RÉSUMÉ. L'impact des prédateurs généralistes sur le déclin des populations de proies constitue un problème majeur en termes de conservation. Toutefois, la gestion de ce problème est entravée par des connaissances limitées quant aux facteurs qui influencent la répartition et l'activité des prédateurs. Dans de nombreuses populations déclinantes d'échassiers à nidification terrestre, un niveau élevé de prédation des nids et des petits empêche la reprise de l'augmentation des populations. Le renard roux, Vulpes vulpes, est le principal prédateur, mais il se nourrit essentiellement de petits mammifères. Dans les prairies humides gérées pour les échassiers nidificateurs, les petits mammifères sont concentrés dans les hautes herbes qui bordent les champs et les nids les plus proches de ces espaces sont les moins susceptibles d'être attaqués. Pour savoir si ces modèles résultent de l'attirance du renard pour les petits mammifères, et par conséquent, pour estimer le potentiel de gestion de la végétation en vue d'influencer les taux de prédation des nids, nous quantifions les variations saisonnières et en termes de localisation par rapport à l'activité des renards et des petits mammifères en relation avec les zones de hautes herbes. Sur les sites ...