Tringa Totanus Research Articles

The recolonization of the Collared Pratincole (Glareola pratincola) in its natural steppe habitats in Hungary – an overview of the species’ grassland activities between 1995 and 2024

Abstract The Collared Pratincole (Glareola pratincola) is an endangered shorebird in Hungary, which disappeared as a character breeding species from its sodic grassland habitats during the mid-1990s. Therefore, it was a positive experience to witness the return of this species to its natural habitats, which we observed and documented in 2022 and 2024, and suggested in 2023. During the 2022 observation, one of the three pairs nesting in the Alsó-Szúnyog-puszta reached the chick-rearing stage. We have summarised twenty-one observations of the species in its natural habitat during the breeding season between 2013 and 2024. Based on our data, Collared Pratincole has been confirmed to breed three times in Hungary in its natural habitats, with five additional instances of assumed breeding between 1995 and 2021. In 2022, the species bred in sodic grassland (Camphorosmetum annuae) grazed with livestock. Pratincoles nested in colonies mixed with Kentish Plovers (Charadrius alexandrinus) and other shorebirds, such as Northern Lapwings (Vanellus vanellus), Black-tailed Godwits (Limosa limosa), and Common Redshanks (Tringa totanus).

Genome-wide DNA reveals decades-long genetic stability and intra-familial migratory site fidelity in an Asian population of Common Redshanks

Genome-wide DNA reveals decades-long genetic stability and intra-familial migratory site fidelity in an Asian population of Common Redshanks

Assessing the effects of long-term habitat reconstruction on breeding shorebird populations in a steppe region

Shorebirds represent key indicator species for evaluating the health of wetlands, as they rely on specific habitats for breeding and foraging. Several restoration actions were initiated to restore these wetlands in the Hortobágy (Hungary), however, their effects have never been assessed. Since birds are good indicators of the health and quality of natural environment and sensitive to changes in land use and climate, we evaluated the restoration actions conducted in the last 20 years using bird monitoring data. Our study focuses on the long-term effects of different habitat restoration actions implemented in the region, which involved no restoration, targeted and non-targeted type of interventions for shorebird management as well as long-term and short-term management. The evaluation is based on long-term monitoring data of shorebird species: Black-winged Stilt, Northern Lapwing, Black-tailed Godwit, Common Redshank and Common Snipe. The effectiveness of restoration actions found to have a species-specific aspect, but in general, our findings indicate positive effects of targeted and long-term restoration actions on breeding shorebird populations. By contrast, targeted but short-term actions led to even worse results for shorebird breeding population size than where no restoration actions were initiated. These findings contribute to a better understanding of the specific habitat requirements of breeding shorebirds in the steppe region and can inform future habitat management strategies. The results can be used in conservation planning and management and highlight the importance of long-term and targeted habitat reconstruction projects in restoring and maintaining breeding shorebird populations.

Declining trends of over-summering shorebird populations along the southeastern coasts of Tamil Nadu, India

Over-summering of shorebirds refers to the phenomenon where certain species of shorebirds, primarily migratory, remain on their non-breeding grounds during the summer months for one or more years instead of migrating to their breeding grounds. The present study investigates the presence and abundance of over-summering shorebird species at four distinct sites covering 24 scanning points along the southeastern coasts of Tamil Nadu for 2017–2023. A total of 13 species were observed over-summering, with Lesser Sand Plover being the most dominant species, followed by Greater Sand Plover. Notably, 10 species were found across all four sites, while three species—Black-tailed Godwit, Bar-tailed Godwit, and Common Sandpiper—were exclusive to Dhanushkodi Lagoon, observed only during 2023. The study examined the year-wise abundance of these species, revealing a decline in over-summering shorebirds across all study sites. The Eurasian Curlew, Curlew Sandpiper, Bar-tailed & Black-tailed Godwits are the ‘Near Threatened’ species observed during the study. Furthermore, the research highlighted variations in Shannon species diversity index (H) location-wise and year-wise – Manoli Island (H = 2.25) in 2023; Dhanushkodi Lagoon (H = 1.8) in 2023; Valinokkam Lagoon (H = 1.63), and Pillaimadam Lagoon (H = 2.08) in 2017. Key findings are that among the study sites, in Pillaimadam Lagoon all 10 species’ abundance declined; in Valinokkam Lagoon, Greater Sand Plover and Little Stint marginally increased, and eight species declined; Common Redshank and Ruddy Turnstone marginally increased in Manoli Island, while other eight species declined; Grey Plover population increased in Dhanushkodi Lagoon along with a marginal decrease in Common Redshank and Ruddy Turnstone as other species declined, over the years of study.

Marsh Harrier Circus aeruginosus diet and hunting habitat selection in the breeding season: implications for lowland breeding waders

ABSTRACT Capsule A temporal mismatch between peak Marsh Harrier hunting activity and wader chick availability means that in most years waders contribute a negligible component of Marsh Harrier breeding season diet when nesting adjacent to lowland grassland, despite a spatial overlap in their habitat use. Aims To examine the potential for conservation conflict with breeding waders by assessing spatio-temporal patterns in Marsh Harrier hunting activity and examining historical and recent data on Marsh Harrier breeding season diet. Methods We monitored Marsh Harrier hunting behaviour in relation to time-in-season and habitat characteristics, and examined nest hatching records of Marsh Harrier and wader nests (Northern Lapwing Vanellus vanellus, Common Redshank Tringa totanus, Black-tailed Godwit Limosa limosa) for evidence of temporal overlap between hunting peaks and predicted wader chick availability. We also recorded prey provisioning to Marsh Harrier broods using nest cameras (2013–2015) and combined this with Marsh Harrier diet studies across Europe from 1942 to 2016. Results Wader adults and chicks contributed only a small proportion (average 1.5%) to the diet of Marsh Harriers nesting adjacent to breeding wader habitats between 1942 and 2016. This was likely due to a temporal mismatch in the peak of harrier hunting and the predicted availability of wader chicks in most years, despite a spatial overlap in habitat use between wader chick-rearing and Marsh Harrier hunting. Conclusion Conservation conflict between breeding Marsh Harriers and waders on lowland grassland is likely to be minimal in most years, with little evidence of waders as harrier prey items. However, harrier hunting activity increases through the breeding season, driven by the timing of their nesting and chick-rearing, and hunting activity was highest over field centres, where waders breed, so later-nesting wader pairs are still at risk. Wader conservation strategies that encourage survival of early wader nests may therefore limit predation and conservation conflict with Marsh Harriers.

Adaptive flight speeds in the Common Redshank Tringa totanus

Adaptive flight speeds in the Common Redshank Tringa totanus

Comparison of waterbird communities in a Mediterranean salina – saltmarsh complex

Coastal wetlands provide habitat for large numbers and many species of waterbirds. Man-made salinas are a particu-lar habitat type often found in such wetlands. This study is an initiative to understand the differences in bird communities between a salina (including evaporation ponds and prebasin) and a saltmarsh. Bird counts and nest surveys took place in the wetlands of Angelochori, Thessaloniki, Greece, in 1991, when the salina was inactive, and in 1997, 2000-01 when it was active. Counts in evaporation ponds were richer in species, abundance and nests compared to the prebasin and the saltmarsh. These three wetland types supported different bird communities. Similarities among bird communities depended on the inundation of the salina with seawater. Evaporation ponds in their inactive period presented low similarity with the communities of the prebasin and the saltmarsh ; in the active period this was observed only for the saltmarsh. Species showing clear selection for the evaporation ponds were Charadrius alexandrinus, Calidris alpina, Calidris minuta, Recurvirostra avosetta, Sterna hirundo, Sternula albifrons, Sterna sandvicensis and Haematopus ostralegus; the prebasin was preferred by Phoenicopterus roseus and Anas platyrhynchos, and the saltmarsh by Anas querquedula, Anas clypeata, Plegadis falcinellus, Tringa totanus, Tringa glareola, Tringa stagnatilis and Himantopus himantopus.

Introduction of summer houses into semi‐natural habitats: impacts on ground‐nesting birds

AbstractDegradation of natural and semi‐natural habitats is often initiated and facilitated by expansions in anthropogenic infrastructures. Identifying and reducing the impact of anthropogenic structures on the wildlife that these habitats support is vital for biodiversity conservation. In Iceland, the number of summer houses has increased over the past two decades, from ~10 000 to 15 000, and >7000 additional plots for summer house construction have been approved. Most of this housing infrastructure development is in the Icelandic lowlands, which support internationally important populations of several ground‐nesting bird species. To explore the effects of summer house infrastructure on the distribution of ground‐nesting birds, we conducted surveys at 292 points within 71 sites with varying density of houses and associated infrastructure (tracks, decking, etc). Significant reductions in abundance with increasing housing density occurred in five (Golden Plover (Pluvialis apricaria), Black‐tailed Godwit (Limosa limosa), Redshank (Tringa totanus), Whimbrel (Numenius phaeopus) and Meadow pipit (Anthus pratensis)) of the seven study species, while one species (Snipe (Gallinago gallinago)) showed no change and one (Redwing (Turdus iliacus)) increased. The differences in abundance between plots with no houses and plots with high house densities (>0.5 houses ha−1) ranged from 34 to 95%, despite the housing infrastructure covering only ~6% of the area of these plots. These findings suggest that even relatively low densities of anthropogenic structures in natural or semi‐natural areas can have substantial impacts on wildlife in the surrounding areas and highlight the urgent need for effective planning regulations to limit the expansion of anthropogenic structures into currently undisturbed habitats, particularly in areas of high biodiversity value.

Shorebird Records from Pangpang Bay, East Java, Indonesia

Pangpang Bay is one of the essential ecosystem areas located in East Java and also it is part of the East Asia Australia Flyway (EAAF). This area is an important habitat as a stopover site for migratory shorebirds. However, heretofore scientific reports are still limited. Therefore, we conducted a shorebird survey in this area on October 1-2, 2022 using concentration count methods at three potential areas. A total of 610 individuals of shorebirds belong to 13 species from two families (Scolopacidae and Charadriidae). Among the observed shorebirds, Whimbrel had the highest number of individuals (n=426), followed by Eurasian Curlew (n=45), Common Sandpiper (n=43), Pacific Golden Plover (n=43), Bar-tailed Godwit (n=14), Common Redshank (n=9), Wood Sandpiper (n=7), Terek Sandpiper (n=5), Ruddy Turnstone (5), Grey Plover (n=3), Common Greenshank (n=3), Javan Plover (n=2), and Greater Sandplover (n=1), respectively. Twelve species are wintering migratory shorebirds and one species (Javan Plover) is a resident species (mostly in Java). Furthermore, shorebirds in Pangpang Bay occupied three habitat types, i.e. mudflat, mangrove forest, and fishpond bordering the mangrove forest. Based on these results, Pangpang Bay is an important habitat for several shorebirds indeed, especially migratory wintering as a stopover site during their migration.

Chewing lice (Phthiraptera, Amblycera, Ischnocera) from shorebirds (Aves, Charadriiformes) in the Kızılırmak Delta, Turkey

This study was carried out in the Kızılırmak Delta Cernek Bird Ringing Station, Central Black Sea Region, during August and September 2020, to survey the louse species found on shorebirds (Aves: Charadriiformes). A total of 241 birds belonging to 13 species were searched for chewing lice. Eleven species in six genera of the family Scolopacidae (Actitis hypoleucos, Arenaria interpres, Calidris alba, Calidris alpina, Calidris falcinellus, Calidris ferruginea, Calidris minuta, Gallinago gallinago, Tringa glareola, Tringa totanus, Xenus cinereus) and two species in one genus of the family Charadriidae (Charadrius dubius, Charadrius hiaticula) were examined. Birds were caught alive with mist-nets, ringed, searched for lice, and released. A total of 153 birds (63.49%) were infested with lice belonging to 16 species, five amblycerans: Actornithophilus bicolor, Actornithophilus ochraceus, Actornithophilus totani, Actornithophilus umbrinus, Austromenopon lutescens, and eleven ischnocerans: Carduiceps fulvofasciatus, Carduiceps meinertzhageni, Carduiceps zonarius, Lunaceps actophilus, Lunaceps falcinellus, Lunaceps schismatus, Quadraceps hiaticulae, Quadraceps obscurus, Quadraceps ravus, Quadraceps strepsilaris and Saemundssonia platygaster frater. These eight species are new records for Turkey: Ac. bicolor, Ac. ochraceus, Ca. fulvofasciatus, Lu. falcinellus, Lu. schismatus, Qu. ravus, Qu. strepsilaris and Sa. platygaster frater. In addition, Qudraceps hiaticulae was recorded from Little ringed plovers (Charadrius dubius)  for the first time in the world in this study. According the lice checklist of wild birds in Turkey, a total of 188 bird species examined and 122 of them were infested, and a total of 217 chewing lice species has been recorded.

The effect of Spartina alterniflora eradication on waterbirds and benthic organisms

There has been an increasing number of coastal restoration projects to eradicate Smooth cordgrass (Spartina alterniflora) and restore bare tidal flats to conserve waterbirds. However, the evidence for the assumed benefits to waterbirds and benthic organisms after such restoration efforts remains limited. We evaluated the impact of S. alterniflora eradication on waterbirds and benthic organisms in southern China. We deployed time‐lapse cameras and satellite trackers to quantify and compare the occurrence frequency and habitat use of birds in different habitats. We compared the density and biomass of benthic organisms collected in bare tidal flats and areas where S. alterniflora had been eradicated. We found that almost all waterbirds, except gulls, avoided areas where S. alterniflora was present. Once S. alterniflora was eradicated, the species richness and species‐level diversity of shorebirds and waterbirds did not differ significantly from those of the bare tidal flats. At least 9 out of 14 tracked individual shorebirds used areas where S. alterniflora had been eradicated, with Common Redshank (Tringa totanus) demonstrating a clear preference for such habitat. The density and biomass of benthos in deeper sediments (5–20 cm below the surface) were significantly lower in areas where S. alterniflora had been eradicated than in bare tidal flats, indicating that the food resources for birds may take longer than 1 year to recover. This research demonstrates that the eradication of S. alterniflora is important for the restoration of waterbird habitats, and such efforts should be made in areas that are important to waterbirds.

Impact of wildfires on ecosystems and bird communities on designated areas of blanket bog and heath

ABSTRACT Capsule Wildfires on moorland reduced bird species richness and abundance, along with the seedbank and abundance of ground beetles and spiders. The effects were detectable three years after the fires took place. Aims To describe the effects of wildfires during the breeding season on moorland birds, their habitat and ecosystem characteristics, by comparing burnt with adjacent unburnt areas in six designated sites up to three years post-fire. Methods Point counts of birds, vegetation height and cover, soil seedbank and pitfall traps were used to examine differences between areas burnt by wildfires and unburnt areas. Results One year after wildfire, bird species richness was 50% lower and abundance 32% lower on burnt compared to adjacent unburnt areas. Wildfire burnt areas had 80% of the species richness and 94% of the abundance of unburnt areas three years after wildfire. Bird species associated with upland moorland, including European Stonechat Saxicola rubicola, Common Redshank Tringa tetanus and Hen Harrier Circus cyaneus, were recorded exclusively in unburnt areas. Wildfire burnt areas were characterized by habitat generalist species and community composition in burnt areas remained distinct from unburnt areas three years after burning. Heather Calluna vulgaris and Erica spp. regenerated to 59% of the height of heather on unburnt areas three years after burning. Compared to unburnt areas, burnt areas had a reduced seedbank (22% lower), and reduced ground beetle (15% lower) and spider abundance (31% lower). Conclusion The immediate impacts of wildfire may differ from managed fires due to their indiscriminate character, where they occur, extent, duration and temperature. Wildfire incidence is likely to increase in cool temperate areas due to climate change and likely to undermine the characteristic features of designated areas. Research should focus on preventing wildfires, reducing their impact and accelerating the recovery of burnt moorland.

Resighting of Indian-marked Common Redshank in Altai territory of south-western Siberia, Russia

Resighting of Indian-marked Common Redshank in Altai territory of south-western Siberia, Russia

Sharing habitat: Effects of migratory barnacle geese density on meadow breeding waders

1.Following targeted conservation actions most goose populations have increased. The growing goose populations caused an increase in human-wildlife conflicts and have the potential to affect nature values. As meadow birds, including meadow-breeding waders, were declining throughout Western Europe, the possible negative effect of rising numbers of foraging barnacle geese on their breeding success has been questioned.2.We used GPS-transmitter data to measure the density of foraging barnacle geese during daylight hours. Using dynamic Brownian Bridge Movement Models (dBBMM), we investigated the effect of barnacle goose density on the territory distribution of five wader species, and on nest success of the locally common Northern lapwing. We used model selection methods to identify the importance of barnacle goose density related to other environmental factors.3.Our results showed an insignificant positive association between barnacle goose density and nest territory density of the Northern lapwing and common redshank. Barnacle goose density had no influence on territory selection of godwit, oystercatcher and ringed plover. We did, however, find a negative correlation between barnacle geese density and the nest success of the Northern Lapwing.4.We infer that either barnacle goose foraging leads to improved territory conditions for some wader species, or that both barnacle geese and waders prefer the same type of habitat for foraging and nesting. Higher barnacle goose density was correlated with fewer Northern lapwing nests being successful.5.Synthesis and application: Experimental research is needed to disentangle the causal chain, but based on our observational findings, we suggest to increase water logging that may attract both barnacle geese and wader species. Further investigation on the effects of barnacle geese on wader species is necessary to identify the cause of the negative correlation between barnacle geese density and nest success of lapwings; nest protection experiments could give further insight.

The effect of conservation interventions on the abundance of breeding waders within nature reserves in the United Kingdom

Breeding populations of many wading birds have declined globally, primarily caused by habitat degradation and loss. In the UK, population declines have been particularly notable on lowland wet grasslands. In response, some areas of lowland wet grassland have been restored and are under ongoing management to improve the breeding conditions of target species. Here, we assess the efficacy of management measures using a Bayesian framework and controlling for confounding factors. We focus on four wader species, Northern Lapwing Vanellus vanellus, Eurasian Curlew Numenius arquata, Common Snipe Gallinago gallinago and Common Redshank Tringa totanus, that breed in numbers on wet grassland reserve sites in the UK. We collated annual site‐specific climate variables, management information (e.g. the creation of wet features and predator control measures) and bird counts between 1994 and 2018. We found the effects of conservation actions varied between intervention types and species. For Lapwing and Redshank, excluding predators by predator‐exclusion fencing, especially in combination with fox control, was generally associated with higher breeding counts. For all study species, sites with longer histories of management were associated with higher breeding numbers, with the effect of site age being particularly notable for management on former arable land. Our findings support the effectiveness of targeted conservation actions to achieve high numbers of breeding waders on lowland wet grassland reserves, and also highlight the value of consistent and reliable monitoring data.

Subarctic afforestation: Effects of forest plantations on ground‐nesting birds in lowland Iceland

Abstract Planting forests is a commonly suggested measure to mitigate climate change. The resulting changes in habitat structure can greatly influence the diversity and abundance of pre‐existing wildlife. Understanding these consequences is key for avoiding unintended impacts of afforestation on habitats and populations of conservation concern. Afforestation in lowland Iceland has been gaining momentum in recent years and further increases are planned. Iceland supports internationally important breeding populations of several ground‐nesting, migratory bird species that mostly breed in open habitats. If afforestation impacts the distribution and abundance of these species, the consequences may be apparent throughout their non‐breeding ranges across Europe and Africa. To quantify the effects of plantation forests on the abundance and distribution of ground‐nesting birds (in particular waders, Charadriiformes), surveys were conducted on 161 transects (surrounding 118 plantations) perpendicular to forest edges throughout Iceland. The resulting variation in density with distance from plantation was used to estimate the likely changes in bird numbers resulting from future afforestation plans, and to explore the potential effects of different planting configuration (size and number of forest patches) scenarios. Of seven wader species, densities of five (golden plover Pluvialis apricaria, whimbrel Numenius phaeopus, oystercatcher Haematopus ostralegus, dunlin Calidris alpina and black‐tailed godwit Limosa limosa) in the 200 m surrounding plantations were just under half of those further away (up to 700 m). Redshank Tringa totanus densities were lowest ≤150 m from the plantation edge while snipe Gallinago gallinago densities were 50% higher close to plantations (0–50 m) than further away (51–700 m), and no consistent effects of plantation height, diameter, density or type were identified. Plantations are typically small and widespread, and simulated scenarios indicated that total declines in bird abundance resulting from planting trees in one large block (1,000 ha) could result in only ~11% of the declines predicted from planting multiple small blocks (1 ha) in similar habitats. Synthesis and application. Planting forests in open landscapes can have severe impacts on populations of ground‐nesting birds, which emphasizes the need for strategic planning of tree‐planting schemes. Given Iceland's statutory commitments to species protection and the huge contribution of Iceland to global migratory bird flyways, these are challenges that must be addressed quickly, before population‐level impacts are observed across migratory ranges.

Effects of overhead power‐lines on the density of ground‐nesting birds in open sub‐arctic habitats

Yearly electricity production has increased steadily worlwide in recent decades and the associated overhead power lines are widespread and occur across urban and natural habitats, and often in remote areas where there is little other anthropogenic influence. Here we assessed the effects of overhead power lines on the density of ground‐nesting birds in the Icelandic lowlands, which host several populations of international importance. The combined breeding density of the eight study species increased significantly from ~ 112 birds/km2 close (< 50 m) to the power lines to ~ 177 birds/km2 away (450–500 m) from the power lines, with two of these species (Eurasian Whimbrel Numenius phaeopus and Common Redshank Tringa totanus) increasing significantly with distance from power lines and six species (European Golden Plover Pluvialis apricaria, Common Snipe Gallinago gallinago, Meadow Pipit Anthus pratensis, Black‐tailed Godwit Limosa limosa, Dunlin Calidris alpina and Redwing Turdus iliacus) showing no changes. These findings suggest that power lines can influence the breeding density of ground‐nesting bird species in their vicinity and that accounting for such effects when planning future infrastructure will be imperative.

Predation‐mediated edge effects reduce survival of wader nests at a wet grassland‐forest edge

AbstractEdge effects occur when the matrix has adverse impacts on the patches of remnant habitat. A widely explored example of this is the hypothesis of a higher predation pressure on bird nests closer to the habitat edge. In parallel with the recent loss of open habitats through afforestation as a climate change mitigation measure, an interest in the impact of forest on species dependent on open habitats has re‐emerged. We follow wader nest survival to study the issue of an edge effect in a system of wet grasslands fragmented by forests in a region where it has not been tested before, focussing mainly on northern lapwing (Vanellus vanellus), common ringed plover (Charadrius hiaticula), common redshank (Tringa totanus) and southern dunlin (Calidris alpina schinzii). To record nest survival, we monitored 753 nests of 10 wader species on coastal grasslands in Estonia for 3 consecutive years. A subset (n = 85) of these nests was equipped with camera traps to record nest predation events and predator association with forest edge. The distance to nearest trees and forest and a forest cover within a 1‐km buffer around each nest was measured. We recorded extremely low daily nest survival rates (0.903–0.922 for different species), with most nests lost to predation. We showed that nest survival is lower closer to the forest edge and negatively affected by the proportion of forest within a 1‐km buffer around each nest. Based on camera trap recordings, we suggest that the edge effect is caused by elevated nest predation rates by the most common predator, the red fox (Vulpes vulpes), closer to the forest edge. Future afforestation plans of open habitats need to acknowledge that the resulting fragmentation has a negative impact on nest survival of ground‐breeding birds. On the other hand, our results imply that restoration efforts aimed at removal of most damaging forest plantations could benefit breeding waders.

Long-Term Changes in the Abundance of Benthic Foraging Birds in a Restored Wetland

Estuaries have historically been subject to considerable habitat loss, and continue to be subjected to such in areas where the natural landward migration of intertidal habitats is constrained by hard coastal defences. Thus, in estuaries where direct (e.g., port development) or indirect (e.g., sea level rise) processes are predicted to threaten intertidal habitats and associated waterbird species, there is a regulatory requirement to produce compensatory intertidal habitats. Managed realignment (MR) is a shoreline management practise that is undertaken to build sustainable coastal defences and create intertidal habitats in estuaries. This nature-based solution brings multiple benefits in the form of carbon storage, increased resilience to flooding, and, potentially, the formation of new habitats, which is the topic of this study. A 75-ha site at the Paull Holme Strays (Humber Estuary, United Kingdom) was monitored over a 10-year period following MR to examine the change in the abundance of waterbirds in the chosen site in response to the physical processes occurring there. Using digital terrain models (DTMs) collected via light detection and ranging (LiDAR), we examined how four compensatory target species responded to changes in elevation after the creation of the site. It was shown that the very rapid accretion of estuarine sediment occurred in the first decade of the new re-created intertidal, which, over time, led to changes in the numbers of benthic foraging birds supported. Furthermore, elevation change was also driven by this sediment accretion, the rate of which depended on the initial bed elevation of the sectors within the site. Ten years after the recreation of the habitat, the spatial heterogeneity in the bed elevation remained high; however, the sectors with the lowest elevations accreted the most over the 10-year period. The foraging number of the four waterbird species that colonised the MR site significantly declined above a certain elevation, with this effect being most pronounced for the Eurasian curlew (Numenius arquata). The number of common shelducks (Tadorna tadorna), dunlins (Calidris alpina), and common redshanks (Tringa totanus) declined significantly after initial peaks 5–7 years after the creation of the site, reflecting the ongoing elevation changes. Thus, this study highlighted the need for long-term studies to understand how species respond to large-scale habitat construction. It can also aid in predicting the suitability of an MR site for waterbirds in the medium and long term.

A counterfactual approach to measure the impact of wet grassland conservation on U.K. breeding bird populations

AbstractWet grassland populations of wading birds in the United Kingdom have declined severely since 1990. To help mitigate these declines, the Royal Society for the Protection of Birds has restored and managed lowland wet grassland nature reserves to benefit these and other species. However, the impact of these reserves on bird population trends has not been evaluated experimentally due to a lack of control populations. We compared population trends from 1994 to 2018 among 5 bird species of conservation concern that breed on these nature reserves with counterfactual trends created from matched breeding bird survey observations. We compared reserve trends with 3 different counterfactuals based on different scenarios of how reserve populations could have developed in the absence of conservation. Effects of conservation interventions were positive for all 4 targeted wading bird species: Lapwing (Vanellus vanellus), Redshank (Tringa totanus), Curlew (Numenius arquata), and Snipe (Gallinago gallinago). There was no positive effect of conservation interventions on reserves for the passerine, Yellow Wagtail (Motacilla flava). Our approach using monitoring data to produce valid counterfactual controls is a broadly applicable method allowing large‐scale evaluation of conservation impact.