Wader Species Research Articles

Whole‐community facilitation by beaver: ecosystem engineer increases waterbird diversity

ABSTRACTWetlands are rich in biodiversity, but globally threatened. After a long period of regional extirpation, beavers have recently returned to many European areas and are now restoring wetlands. The beaver is remarkable regarding the large impacts it has not only on individual species but on entire communities and ecosystems. In fact, beavers are referred to as ‘ecosystem engineers’.The facilitative effect of the beaver Castor canadensis on a waterbird community of seven species of waders and ducks in boreal ponds was studied by using the before–after control–impact method (BACI) and analysing the effect of the duration of flooding. The before–after setting could be used since beavers had caused disturbance by flooding several forest ponds during the course of this long‐term study (1988–2009). The study took place in southern Finland, where waterbirds were surveyed four times during the breeding season.The number of waterbird species per pond per year was significantly higher during beaver inundation than before beaver activity, as was the waterbird abundance per survey. Changes were negligible in the controls. The numbers of all seven species increased during flooding, although the increase was significant in only three species. Common teal Anas crecca and green sandpiper Tringa ochropus showed the most positive numerical response to flooding. Mallard Anas platyrhynchos and wigeon Anas penelope were new species entering the duck guild in the flooded wetlands. The beneficial effect of the flood lasted the whole period of inundation, although the most substantial increase in species number appeared during the first two years of flooding.The beaver acted as a whole‐community facilitator for waterbirds. It was inferred from previous studies that this was done by modifying the habitat to make it more productive and structurally favourable. It is concluded that favouring beavers is a worthwhile tool in restoring wetlands to promote waterbird communities. Copyright © 2014 John Wiley & Sons, Ltd.

Cliff top habitats provide important alternative feeding resources for wading birds of conservation importance wintering on non-estuarine coasts

Rocky shores and beaches are important over-wintering areas for non-estuarine waders but have rarely been studied. We examined cliff top habitat use by 6 species of wader over 75 km of coast to assess their potential value as alternative feeding sites to rocky and sandy shores. Both the regional and local survey showed that waders occurred on golf courses and recreational grasslands in higher frequencies than expected but arable and pasture use was lower than expected. We also compared local wader densities on rocky and sandy shores, pastures, golf courses, caravan parks and recreational grasslands over two winters. Sanderling predominantly fed on the beach whereas Oystercatcher, Dunlin, Turnstone and Redshank numbers significantly increased on golf courses and recreational grasslands over the winter period, with pasture being rarely used. General linear models were used to relate environmental factors to the presence and absence of each species on the cliff top habitats. Redshank was the only species that showed a higher probability of occurrence on cliff top habitats at high tide whereas the probability of Turnstone, Oystercatcher and Redshank occurring increased as temperatures declined. Using core sampling, we determined that invertebrate richness and abundance was significantly higher on the recreational grasslands and golf courses than on the pasture or the beach. Our data demonstrated that cliff top habitats are important alternative feeding areas for over-wintering waders in areas where the intertidal is bounded by cliffs. Current management creates short sward, open field habitats with a diverse and abundant invertebrate food supply exploited by waders. Any alterations to the land use of these areas should be carefully considered by planning authorities in light of the fact that they support species that are of conservation concern.

Littoral invertebrates in waders’ nutrition at migratory stopover sites in the Azov and Black Sea region

Seasonal migration for birds – distant migrants are the most energy intensive. Fat reserves accumulated in the bird’s body before migration and during migratory stopovers determine success of the long-distance flight. Lipids play a vital role both as a source of energy and as structural components of cell membranes. For most migrants to the speed and quality processes fat accumulation affects the feed ration in the field of migration stops. Fodder saturation with essential polyunsaturated fatty acids (PUFAs) is of great importance. Being paramount for physiological processes, these acids cannot be synthesized in the bird’s body. The proposed article is dedicated to the study of waders’ trophic relationships with their prey items, and the use of PUFAs as biochemical markers. This approach is based on the specificity of the fatty acids contained in the lipids of invertebrate to be used as food bird species studied. Significant amount NPZHK waders obtained from forage that can be considered PUFAs as biochemical markers to determine the range and diversity of food producing birds PUFAs ways, and also to study the food chain in ecosystems. A fatty acid spectrum (FAS) of the lipids common for nine littoral invertebrate species (Gammarus aequicauda, Idotea balthica, Artemia salina, Nerеis sp., Nerеis zonata, Theodoxces astrachanicus, Hydrobia acuta, Chironomus salinarius, Chironomus plumosus), which constitute the main component of waders’ diet at the migratory stopover sites in the Azov and Black Sea region, has been studied. Found that the largest amount of total lipids contained in Nereis zonata (4,6 %) and Artemia salina (4,4 %), the lowest amount of total lipids was observed in Chironomus (1,5–1,8 %), which implies that polychaete worms and Artemia salina, as a source of fat, are the most productive for waders. Our research has found that mollusks, polychaete worms, and Artemia salina are the most effective waders’ fodder in the PUFAs content. Mollusks contain the largest amount of PUFAs, their spectrum is ω3 and ω6 PUFAs, especially arаchidonic acid C20:4. Polychate worms are also characterized by a high PUFAs level; they serve for birds as a source of linolenic and linoleic acid groups. Artemia salina contains a large amount of eicosapentaenoic С20:5ω3 and docosahexaenoic С22:6ω3 acids, which getting to an organism of birds, participating in the formation of cell membranes, act as thermal stabilizer lipid bilayers, enhance stamina during long-distance flight. A high abundance of Artemia salina in the feeding areas permit tundra waders to use them as a prey item, which can fulfill the bird’s body with a required amount of fatty acids in a short time. We have established an influence of some environmental factors, as water temperature and salinity, on the lipids FAS of littoral invertebrates. Spectrum analysis of polyene fatty acids in the lipids closely related species of invertebrates living in different salinity water showed that the content of PUFAs in the lipid depend on their food spectrum, and the environmental conditions. Therefore, anthropogenic pressure and changes of water hydrological regime may affect PUFAs content in the lipids of littoral invertebrates. In its turn, this factor may change alimentary behavior and migratory strategy of the birds, which use migratory stopover sites in the region in question. Shallow waters of the Azov-Black Sea region are characterized by different climatic characteristics and a large reserve of phytoplankton. This explains the mass character species studied of invertebrates to feeding areas and their use as basic prey items, many species of waders.

Sex ratios of waders at the northern end of the East Atlantic flyway in winter

Capsule Sex ratios were determined for 11 wader species at the northern end of the East Atlantic flyway in winter. The ratio was even for six species, there were more males for four species, and more females for one species.Aims To describe the sex ratio of adult waders in northern Scotland and examine departures from parity.Methods Molecular sexing and biometrics were used to estimate the sex ratio (percentage male) in adult populations of 11 waders wintering on estuaries and open shores in northern Scotland (Moray Firth and Orkney), at the northern part of the East Atlantic flyway. Departures from parity were examined in relation to three possibilities: (1) that there was local variation in the distribution of the sexes; (2) that the sexes differed in their winter ranges and (3) that there was an uneven sex ratio in the entire population.Results The percentage of males did not differ significantly from 50% for Lapwing, Ringed Plover, Dunlin, Knot, Sanderling and Turnstone. There were significant differences from parity for Oystercatcher, Redshank, Bar-tailed Godwit and Curlew at some sites, suggesting local segregation of the sexes that may be related to habitat. It was difficult to examine possibilities 2 and 3 due to the lack of data from other parts of the flyway. Only some populations of Purple Sandpipers and perhaps Bar-tailed Godwits exhibited an uneven sex ratio in favour of males across the flyway. For these species, the uneven sex ratio in favour of males was already apparent in first-year birds, showing that higher mortality amongst juvenile females, rather than higher mortality amongst breeding females probably causes the imbalance.Conclusion Some waders showed significant deviations from parity in their sex ratio. These may be due to sex-dependent habitat selection and differential mortality rates.

Modelling edge effects of mature forest plantations on peatland waders informs landscape‐scale conservation

Summary Edge effects of native forest fragmentation have been well studied, but there are few studies of open‐ground habitats fragmented by plantation forests. We measure forestry edge effects on open‐ground breeding birds, following one of Europe's biggest and most controversial land‐use transformations. The ‘Flow Country’ of northern Scotland is one of the world's greatest expanses of blanket bog. It became fragmented by conifer forests planted in the late 20th century, and these now adjoin open peatlands protected under European conservation legislation. Detrimental edge effects on breeding birds were anticipated, but not apparent shortly after planting. Using survey data collected in 2003–2006, and logistic regression modelling, we tested whether breeding distributions of three wader species of international conservation concern, dunlin, European golden plover and common greenshank, were influenced by distance to forest edge, controlling for habitat and topography. All three species were more likely to occupy flatter, more exposed ground close to bog pools and were influenced by peatland vegetation structure. There was an additive and adverse effect of proximity to forest edge for dunlin and European golden plover, but not common greenshank. This effect was strongest within 700 m of forest edges. We used these results to predict which areas should benefit most from removal of adjacent forestry and so guide maintenance and restoration of the bird interests of the protected areas. Synthesis and applications. Edge effects of mature forestry on dunlin and golden plover are apparent over several hundred metres and are now being used to guide forest planning in northern Scotland. The scale of edge effect is broadly consistent with other avian studies in open‐ground habitats across Eurasia and North America, so buffer zones of this order are consistent with possible impacts of plantation forestry on open‐ground habitats of bird conservation interest. Given renewed interest in conifer afforestation as a climate change mitigation measure, an improved understanding of edge effects and the mechanisms through which they operate is vital to managing plantation forestry in ways that maintain open‐ground landscapes of high conservation value.

Variation in the Responses of Wild Species of Duck, Gull, and Wader to Inoculation with a Wild-Bird–Origin H6N2 Low Pathogenicity Avian Influenza Virus

There is poor understanding of host responses to avian influenza virus (AIV) infection in wild birds, with most experimental studies using captive-bred birds and highly pathogenic AIVs that have an early endpoint. The objective of this study was to experimentally assess antibody responses and patterns of viral excretion in wild birds challenged with a low pathogenicity AIV. Ruddy turnstones (Arenaria interpres), silver gulls (Chroicocephalus novaehollandiae), and wandering whistling ducks (Dendrocygna arcuata) were challenged with a H6N2 virus, and blood, cloacal, and oropharyngeal (OP) swabs were analyzed from each bird over 28 days, with serology conducted on the ducks for a further 7 mo. Nineteen of 22 birds showed evidence of infection, with respiratory infection prevalent in the turnstones and gulls as mostly low titer viral excretion to 4 days postinoculation (DPI) with gastrointestinal replication detected in only one turnstone. In AIV naive ducks, there was gastrointestinal tropism with moderately high titer viral excretion via the cloaca to 6 DPI and low-grade OP viral excretion to 4 DPI. The hemagglutination inhibition antibody response was poor in the ducks, declining from 19 to 56 DPI, with higher titer responses in the gulls and turnstones. All infected birds responded with elevated nucleoprotein antibodies (in competitive enzyme-linked immunosorbent assay) by 7-10 DPI, and in the ducks these waned slowly after 42 DPI and were long-lived to at least 8 mo. The interspecies variability in response was consistent with a subtype that had adapted well in ducks, while the response of the turnstones may have been influenced by preexisting immunity to AIV. These findings provide insight into AIV infection dynamics in wild birds and highlight the need for further research.

Suitability, success and sinks: how do predictions of nesting distributions relate to fitness parameters in high arctic waders?

AbstractAimAlthough habitat suitability maps derived from species distribution models (SDMs) are often assumed to highlight locations that can sustain healthy populations over time, the relationship between suitability scores and fitness parameters has rarely been tested thoroughly.LocationZackenberg Valley, north‐east Greenland.MethodsUsing 14 years of data (1997–2010) representing three wader species (dunlin Calidris alpina, sanderling Calidris alba and ruddy turnstone Arenaria interpres), we tested the relationships between modelled suitability and fitness parameters at nesting locations.ResultsAmong the three species examined, only the ruddy turnstone exhibited significant relationships between suitability and nest success, but over time rather than space. During years with extensive snow cover in the landscape, the nesting sites of ruddy turnstone occurred in different habitats than were typically used across years. Moreover, in years with extensive snow cover, the ruddy turnstone initiated nests later and suffered from higher egg predation rates.Main conclusionOur results suggest that SDMs derived from species occurrences that include years of low reproductive success may over‐estimate the potential suitable habitat in the landscape. Whenever possible, variation in reproductive success should be considered when building models to inform species' response to environmental change.

Variable flight initiation distance in incubating Eurasian curlew

Flight initiation distances (FIDs) of nesting birds approached by a predator likely reflect evolutionary stable strategies in which birds make trade-offs between adult survival and reproductive success. Here, we test if FID (a) had an impact on hatching success, (b) was adjusted to current conditions, and (c) was consistent for individual nests. All experiments were performed with a human approaching incubating Eurasian curlews Numenius arquata, a ground-nesting wader species under high egg predation pressure. Our results show that hatching success was higher in nests where the incubating parent left at intermediate FIDs compared to short and long ones, and that FID decreased with date and time of the evening. Further, FIDs from repeated approaches were not consistent within nests. We suggest that incubating Eurasian curlews follow a “surprise” strategy, where an element of randomness is superimposed on a context-adjusted norm to prevent predators from predicting their FID behaviour.

Міграція набережника Actitis hypoleucos L. (Aves: Charadriiformes) в орнітологічному заказнику “Чолгинський”

Peculiarities of migration, biometrics and stopover ecology of Common Sandpiper ( Actitis hypoleucos L.) in the Cholgini ornithological reserve (West Ukraine) are discussed. Main autumn passage of the species occurs from second decade of July to second decade of August. Average number of migrants per one count didn’t exceed 2–3 individuals. Mean passage date on autumn migration was 30 July. First quartile – 19 July, second – 15 August. Frequency distributions of all biometrical measurements except of weight were unimodal. Average stopover length equals 3.9 days. Potential flight range of juvenile birds reaches 3 901 km, adult – 4 602 km. Therefore, fat reserves deposited in the reserve are not enough to reach main wintering grounds in Central Africa. On the studied territory Common Sandpipers migrate as S-strategists, depositing fat reserves during long time period. This is also confirmed by high fat amounts in that species and high potential flight range in comparison to other species of waders. Keywords : waders, Charadrii, migration, Common Sandpiper, Actitis hypoleucos, biometry.

A Multilevel Core Sampler Device to Directly Estimate Food Supply Accessible to Waders

To understand food webs functioning in intertidal soft-sediments, it is critical to assess the macrobenthic prey fraction accessible to waders. Here we describe a simple core sampler device allowing to directly relating the vertical distribution of macrozoobenthos to waders bill length. Bill length measurements were used as a proxy of probing depth to estimate the amount of food supply accessible. Several metal plates can be inserted in the core sampler at different heights according to the bill length data of the studied species. These data are provided in a literature survey. For each species, the bill length variability is then explicitly taken into account in the estimation of food accessibility. The core is transparent to check for the quality of the sample. It could also be used to estimate a Benthic Habitat Quality index (BHQ) based on characteristics of the vertical structure of the sediment. This multilevel core is easy to build and to adapt to any studied wader species of the intertidal zone, floodplains or other wetlands. The samples are obtained with the same effort as with usual circular cores leading to the possibility to survey large area. With one core sample, the ecological information that can be achieved at once is threefold: 1) benthic community structure (partitioned in several depths), 2) estimate of the accessible food fraction to waders (range of values) and 3) habitat quality index assessment.

Censuses of breeding birds in a South Norwegian arctic-alpine habitat three decades apart show population declines in the most common species

Breeding bird censuses along line transects on the Hardangervidda plateau, southern Norway, were performed on open mountain heath at about1250 m elevation in 1980 and repeated in 2010 and 2011. Four passerine species and three species of waders constitute the commonest breeders. Significant decrease in numbers was found in the three commonest species, Meadow Pipit Anthus pratensis (down 40 %), Northern Wheatear Oenanthe oenanthe (down 65–67 %) and, in particular, Lapland Bunting Calcarius lapponicus (down 82–87 %). The decline in Lapland Bunting is discussed in relation to changes in the vegetation on the breeding grounds probably caused by reduced grazing and climatic changes, and in relation to possible negative factors in parts of the wintering area.

The use of predator-exclusion fencing as a management tool improves the breeding success of waders on lowland wet grassland

Waders breeding on lowland wet grassland have undergone dramatic declines across Europe in recent decades. Few species now achieve the levels of breeding success required for population stability and recovery, with predation from large mammals acting as a key compounding factor limiting nest survival and productivity. Predator management through lethal control is often controversial, yet alternative non-lethal methods are little tested in the context of grassland breeding waders. Excluding predators through the use of electric fences has led to improvements in nest and chick survival in other habitats. To test the applicability of this method to lowland wet grassland we constructed predator-exclusion fences on sites across the UK and, with Lapwing Vanellus vanellus as a study species, used historical and contemporary data to test whether excluding large mammalian predators leads to an increase in wader nest survival and productivity, and whether effects differ between fence designs. Lapwing nest survival was significantly higher in the presence of any type of predator-exclusion fence, with significantly fewer nests predated each day. Overall productivity also improved, with significantly higher numbers of chicks fledged per pair in years when fences were operational. Different designs and methods of powering fences resulted in different levels of success, with combination design fences and those powered by mains electricity performing best. Excluding large mammalian predators from areas of lowland wet grassland with predator-exclusion fencing successfully improves Lapwing nest survival and productivity, allowing breeding success to exceed the levels required for population recovery. Other wader species breeding in the same habitat are also likely to benefit from the increased protection from predation provided by fences. Predator-exclusion fencing is therefore an effective management tool for protecting restricted and declining populations of breeding waders on lowland wet grassland.

Abundance and Factors Affecting Population Characteristics of Waders (Charadriiformes) in Great Vedaranyam Swamp of Point Calimere Wildlife Sanctuary, South-east Coast of India

The abundance and factors affecting the population characteristics of waders in Great Vedaranyam Swamp was studied during 2007-2010. This wetland is a Ramsar site and an Important Bird Area. This habitat attracted 30 wader species, which are local and migratory bird species. Highest population of Greater Flamingo Phoenicopterus ruber was recorded in all the years of study period. The physico-chemical parameters such as calcium, chloride, dissolved oxygen, electrical conduc- tivity, magnesium, nitrate, nitrite, pH, phosphate, total dissolved solids, salinity, sulphate, turbidity, water depth and water temperature have been tested. The physico-chemical parameters were compared with the small and large waders density (birds / km 2 ) and diversity (H'). The multiple regression models were made to evaluate the relationship between the phys- ico-chemical parameters and waders population characteristics. Such a water quality parameters showed significant varia- tions among the variables. The abundance of phyto and zooplankton, polycheates, gastropods and decapods, the prey items of the bird were also compared with water quality parameters that showed significant variations. The result suggests that physico-chemical parameters of water as a vital role to regulate the bird community and their prey items.

Identification of Black-tailed Godwit’s Limosa limosa breeding habitat by botanical and environmental indicators

Despite concentrated conservation efforts and targeted agri-environmental schemes, breeding wader species have declined in most western European countries during recent decades. Assuming that wader species aggregate in relation to physical and biological features of their breeding habitats, this study aimed to identify botanical and environmental indicators that can be used to identify sites and management regimes to enhance breeding potential for the Black-tailed Godwit Limosa limosa as a focal species. We selected 36 fields (mean 7.1 ha) with and without this species in grazed lowland grasslands in the Danish Wadden Sea area. Bird numbers observed during 2007 and 2008 were analysed in relation to environmental and management variables together with presence/absence of plant species in the main body of the fields, the field silt trenches and field edges. Black-tailed Godwits preferred unfertilized fields with a short growth plant community that included the presence of moss-carpet. The plant indicator species for fields with Black-tailed Godwit were besides Bryopsida (moss sp.) also Trifolium pratense var. maritimum (maritime red clover), Poa trivialis (rough meadowgrass), Plantago major (greater plantain) and Veronica serpyllifolia (thyme-leaved speedwell).

Nest Success of Black-Winged StiltHimantopus himantopusand Kentish PloverCharadrius alexandrinusin Rice Fields, Southwest Spain

We monitored nests of Kentish Plover Charadrius alexandrinus and Black-winged Stilt Himantopus himantopus breeding in rice fields near the Doñana National Park (southwest Spain) during the breeding seasons 2005–2007. We used a logistic-exposure method to calculate nest success and examined daily nest survival as a function of year, locality, nest age, and date. Nest success was also calculated using a model assuming constant nest survival through time (equivalent to the Mayfield method). Daily nest survival increased during incubation in Black-winged Stilt, probably due to a higher predation risk during the first days of incubation. Daily nest survival in Kentish Plover showed little variation in relation to nest age, suggesting a constant but lower predation rate. Nest survival also varied with date in Kentish Plover and showed higher values in the middle of the nesting season. The nest success of Black-winged Stilt and Kentish Plover breeding in rice fields (50% and 45%, respectively, based on the Mayfield method) was within the range of nest success reported in stable populations breeding in natural habitats. The observations suggest that rice fields adjacent to the marshes of the Doñana National Park are an important additional breeding habitat for the two wader species studied.

Local and global influences on population declines of coastal waders: Purple Sandpiper Calidris maritima numbers in the Moray Firth, Scotland

Declines in numbers by several wader species in Britain have been linked to climate change, but the mechanism for the declines has rarely been explored. Britain lies at the northern end of the East Atlantic Flyway, and supports 1.3 million out of the Flyway's 8.5 million coastal waders (Charadrii) in winter and the Purple Sandpiper is one of the species whose numbers have declined. Here, we examine the dynamics of the decline as observed in the Moray Firth, northeast Scotland, investigating whether the decline was due to poorer apparent survival (return rate) or poorer recruitment of young birds. The maximum number in the Moray Firth declined from 860 in 1987/88 to 236 in 2006/07, with some increase during winters 2007/08 and 2008/09. At the three main high-tide roosts (Balintore, Lossiemouth and Buckie) the maximum combined number declined from 574 to 90. Changes in survival and recruitment (percentage of first-year birds) were examined at these roosts from captured samples, which were ringed and recaptured. There were no significant changes between winters in survival rates, nor were there differences between the survival rates of age groups (first-year and adult) or bill size groups, which represented birds of different sex and breeding origin. Annual survival estimates for the three roosts ranged from 72 to 77%. The percentage of first-year birds varied among roosts and years; the lowest values were during the late 1980s/early 1990s and early 2000s. A free-running population model incorporating varying percentages of first-year birds and constant mortality for each roost provided a plausible explanation for the decline. Although modelled numbers followed the observed pattern, a discrepancy in one year was carried forward in subsequent years, so that the fit with the observed numbers was parallel rather than similar. However, it seems that the decline in numbers was largely due to poorer recruitment. We discuss whether breeding success had declined, whether the population had responded to changes in the local sewage treatment systems, which could affect invertebrate food for Purple Sandpipers, or whether fewer birds chose to winter in Scotland. The Moray Firth population is derived from Norway and possibly Canada, and there is evidence that the Norwegian population was disproportionately affected. The reason for poor recruitment requires further study, and other wader species require examination to test if poor recruitment is a common feature of decline in numbers.

Survey and conservation of the critically endangered Spoon‐billed Sandpiper in Bangladesh

Survey and conservation of the critically endangered Spoon‐billed Sandpiper in Bangladesh

Population changes of breeding waders on farmland in relation to agri-environment management

Capsule Population response of breeding waders to agri-environment management varied between management options and species; implementation has been on too small a scale to reverse national population declines. Aims To test whether numbers of five breeding wader species have shown a more positive response between 1992 and 2005, at sites with appropriate agri-environment management, than at sites that have remained outside such schemes. Methods Using data from 60 pairs of farmland study areas in Scotland first surveyed in 1992/93, before agri-environment scheme (AES) implementation, and again in 2005, after scheme implementation, we tested at both site and field scales whether changes in the abundance of five breeding wader species were associated with AES management options designed to benefit these species. Results Changes in breeding wader abundance were more positive on sites in AES, especially for Northern Lapwings Vanellus vanellus and Common Redshanks Tringa totanus, even though management had not been targetted specially at breeding waders on those sites. However, AES management was associated only with modest population increase for Common Redshanks, and a reduction in the magnitude of decline for Northern Lapwings. At the field scale, there was evidence for Northern Lapwings, Common Redshanks and Common Snipe Gallinago gallinago that options which limited grazing and other agricultural activity were associated with more positive outcomes than those which also manipulated water levels. Conclusions AES management for breeding waders slowed, and in some cases reversed, breeding wader decline at field and farm scales. These benefits were from options that limited grazing and agricultural operations during the breeding season, but not those that also aimed to raise water levels. A possible explanation is that when wetland options are applied to agriculturally marginal fields, grazing reduction or abandonment, and succession to rank vegetation cover then occur over the course of 5-year agreements, with detrimental effects for breeding waders. Verification arrangements need to be robust enough to guard against this. Levels of agri-environment provision in 2005 were too limited and too poorly targeted at remaining key areas for breeding waders to be able to halt or reverse national population declines.

Egg hatchability in high Arctic breeding wader species Charadriiformes is not affected by determining incubation stage using the egg flotation technique

Capsule By following the fate of both floated and non-floated eggs from individual clutches of four Arctic wader (shorebird) species, we show that the use of the flotation method for determining incubation stage of eggs (which involves both the submersion and handling of eggs) does not negatively affect hatchability.

Exclusion of ground predators improves Northern Lapwing Vanellus vanellus chick survival

Many farmland-breeding wader species have declined across Europe, probably due to reductions in reproductive output caused by high nest losses as a result of agriculture or predation, or low chick survival between hatching and fledging. Most studies have focused on nest failures, and the factors affecting post-hatching survival of chicks are poorly known. In an experimental approach, we fenced parts of the arable foraging areas of Northern Lapwing Vanellus vanellus families to quantify chick survival simultaneously in the presence and absence of ground predators. Lapwing chicks were radiotagged to estimate survival probabilities by daily locations, applying multistate capture–recapture models. During the night, chick survival was considerably lower outside fenced plots than within. During the day, chick survival was higher than at night and did not differ between protected and unprotected plots. This suggests that nocturnal ground predators such as Red Foxes Vulpes vulpes were responsible for a significant proportion of chick mortality. Cumulative survival probability from hatching to fledging was 0.24 in chicks within fenced plots, but virtually zero in chicks outside fenced plots. In farmland, temporary electric fences can be effective in minimizing the impact of ground predators and offer a promising short-term method to increase fledging success of precocial birds.