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Yellow rust, caused by Puccinia striiformis f. sp. tritici (Pst), is economically one of the most important diseases of wheat in India and worldwide. During four wheat-growing seasons (2015-19), a total of 951 yellow rust samples collected from farmers’ fields (n = 602) and trap plot nurseries (n = 349) were analyzed for virulence on 30 differentials. From this analysis, 11 distinct Pst pathotypes were identified. The virulence pattern of these pathotypes was also tested on 14 Avocet near-isogenic lines (NILs) and Avocet S. None of the pathotypes were virulent to Yr5, Yr10, Yr15, Yr16, Yr24, Yr32, and YrSP. Pathotype 46S119 (46E159) was most prevalent and widely distributed in all the areas and its overall frequency was maximum (56.2%) followed by 110S119 (110E159, 31.9%). However, the frequency of 46S119 has decreased gradually from 62.0% (2015-16) to 48.4% (2018-19). Pathotype 238S119 (238E159) being the most virulent among the identified pathotypes, was detected in 6.8% of samples. Each of the remaining pathotypes was identified in

Highlights: • A combination of methods is necessary to assess the foraging ecology of avocets. • Marine fish make up a higher proportion of the diet than previously assumed. • Telemetry data indicate that intertidal channels are important foraging grounds. • Avocet behaviour implies high fish densities in intertidal channels. • Protected areas are important habitats for breeding, resting and foraging avocets. Abstract: Pied avocets (Recurvirostra avosetta) breeding in the Wadden Sea typically forage in shallow water, using their characteristic upward-curved bill to feed on macrozooplankton in the water column and prey items in the uppermost centimetre of the sediment. Former studies on prey choice based on droppings and visual observations of feeding behaviour suggested that ragworms were the main prey items of avocets. The present study combined different methods to assess the foraging ecology of breeding avocets in the eastern Wadden Sea. Important foraging grounds were identified using GPS telemetry. Diet was analysed from droppings and stable isotope signatures of whole blood samples from breeding avocets at two different colonies in April–June 2014 and 2015. Analysis of droppings confirmed the former results, but stable isotope analysis suggested that marine fish comprised the highest proportion of the avocet diet by mass. Telemetry data indicated that intertidal channels close to the breeding areas were used as the main foraging grounds. Avocets performed short foraging trips (maximum distance: 0.3–5.9 km) mainly during the daytime. Logger data and diet analysis thus implied the existence of high fish densities in intertidal channels, underlining the importance of this saltmarsh habitat as foraging areas for breeding avocets.

Absent as a breeding bird from Britain for at least a century, avocets (Recurvirostra avosetta) began nesting on the east coast of Britain, in Suffolk, shortly after the end of the Second World War, having homed in on two spots on Britain’s coast that had been flooded for war-related reasons. The avocets’ presence was surrounded in secrecy, while a dedicated few kept up a protective watch over them. As the Royal Society for the Protection of Birds (RSPB) took over responsibility for the flourishing colony, they claimed the episode as a symbol of success for British protection, later making the bird their logo. Counter to the RSPB’s story of protecting a British bird, I read the narratives of events in terms of making a bird British. I show how, as postwar Britain slumped economically and spiritually and tried to rebuild itself, the birds became a vehicle for formulating national identity: of Britain as a home to which to return and belong. Exploring the themes of returning servicemen and closed territories, the paper also examines the episode in terms of the naturalisation of the military and the militarisation of nature.

Predators that feed on clustered prey tend to have an ‘area-restricted search’ (ARS), characterized by a combination of a slow and tortuous movement in prey-rich areas, and a fast and straight movement in poorer areas. Waders that forage in intertidal areas usually prey upon buried macroinvertebrates, whose distribution is often clustered. However, wader species differ in the strategy used to find their prey: some rely mainly on visual cues, some rely on tactile cues, and others follow a more generalist method, simply sweeping the sediment surface with the bill. We hypothesized that these strategies influence the adoption of an ARS by waders. We analysed this hypothesis by comparing the fine-scale movement of a ‘tactile’ predator (black-tailed godwit, Limosa limosa ), with that of a ‘visual’ predator (redshank, Tringa totanus ) and a ‘sweeper’ (avocet, Recurvirostra avosetta ). We filmed 190 individuals of the three species and, using GIS facilities, obtained more than 12 000 spatial positions, along with detailed records of feeding activity. We analysed several parameters of fine-scale movement of waders, such as foraging and searching speeds, tortuosity, and the relationship between these parameters and foraging success. Only the tactile predator, the black-tailed godwit, followed an ARS, reducing searching speed and increasing spatial turning rate whenever the prey intake was higher. Furthermore, its foraging strategy involved short-term adjustments of movement that maximized the likelihood of finding subsequent prey, suggesting a prior knowledge or an ability to perceive rapidly the distribution pattern of its prey.

Estuarine sediment flats are essential feeding areas for waders, but their exploitation is constrained by the movements of tides. In this cyclic environment the exposure period of sediment flats decreases several fold from upper to lower flats, and the moving tidal waterline briefly creates particular conditions for waders and their prey. This study attempts to determine how the exposure period and the movement of the tide line influence the use of space and food resources by waders across the sediment flats. Wader counts and observations of feeding behaviour were carried out in all phases of the tidal cycle, in plots forming a transect from upper to lower flats, thus representing a gradient of exposure periods. Pecking, prey intake, and success rates varied little along the gradient. Some species actively followed the tide line while foraging, whereas others are evenly spread over the exposed flats. Black-tailed Godwit, Dunlin and Avocet were 'tide followers', whereas Grey Plover, Redshank and Bar-tailed Godwit were 'non-followers'. Densities of 'followers' near the tide line were up to five times higher than elsewhere. Species differed markedly in the way they used space on the flats, but in general the rate of biomass acquisition (in grams of ash-free dry weight per time exposed) was much higher in lower flats. However, this preference was insufficient to counter the much longer exposure of the upper flats, so the total amount of biomass consumed on the latter was greater. Therefore, it was in these upper flats that waders fulfilled most of their energetic needs. Consequently, upper flats are of particular importance for the conservation of wader assemblages, but because they are usually closer to shore they tend to suffer the highest pressure from disturbance and land reclamation.

Attempts to reverse the population declines of many wader species in Denmark and other parts of Europe during the last 20–30 years have resulted in the application of several management implements. In this study we evaluate the effect of two management implements (grazing by cattle and winter flooding) on the number of breeding pairs of lapwing, redshank, avocet, ringed plover, and oystercatcher in the Klydeso reserve, eastern Denmark, from 1990 to 2001. We also include a proxy of winter climate, the index of the North Atlantic Oscillation (NAO), in our models in order to quantify the relative importance of the applied management and winter severity. Lapwing and avocet breeding numbers increased significantly concurrent with the application of cattle grazing, most likely due to an increased number of nesting sites and/or improved predator detection. Conversely, oystercatcher breeding numbers declined as the fraction of the reserve grazed by cattle increased, which may be attributed to changes in food availability on the grazed areas, but also due to increased predation risk. Ringed plover and redshanks in particular responded positively to the introduction of winter flooding, possibly due to increased availability of suitable foraging sites. Ringed plover may also experience increased nest site availability after winter flooding. Oystercatcher and ringed plover were both affected by winter severity, but with opposite trends, and oystercatcher breeding numbers increased after mild winters, while ringed plover decreased. Remaining species were not influenced by winter severity. The possible reason for this is discussed by comparing the lapwing breeding numbers in Klydeso reserve to Tipperne reserve in western Denmark. Though winter severity may seem of no importance for some of the species in the Klydeso reserve, it may still be important in areas where the management effort is constant. Die Versuche, die Populationsabnahme vieler Watvogelarten in Danemark und anderen Teilen Europas in den letzten 20–30 Jahren umzukehren, resultierten in der Anwendung verschiedener Management-Methoden. In dieser Studie bewerten wir die Auswirkung von zwei Management-Methoden (Viehbeweidung und Winteruberflutung) auf die Anzahl der Brutpaare von Kiebitz, Rotschenkel, Sabelschnabler, Sandregenpfeifer und Austernfischer im Klydeso Schutzgebiet, ostliches Danemark, von 1990 bis 2001. Wir nahmen ausserdem eine Stellvertretervariable fur das Winterklima in unsere Modelle auf, den Index der Nordatlantischen Oszillation (NAO), um die relative Wichtigkeit des angewendeten Managements und der Winterharte zu quantifizieren. Die Brutvogelzahlen von Kiebitz und Sabelschnabler nahmen signifikant mit dem Einsatz der Viehbeweidung zu, am wahrscheinlichsten aufgrund einer erhohten Anzahl von Brutplatzen und/oder aufgrund einer verbesserten Rauberwahrnehmung. Die Brutvogelzahl der Austernfischer nahm dazu gegenlaufig mit der Zunahme des von Vieh beweideteten Anteils des Schutzgebietes ab, was auf die Veranderung der Nahrungsverfugbarkeit in den beweideten Flachen zuruckzufuhren sein mag, aber auch auf ein erhohtes Pradationsrisiko. Besonders die Sandregenpfeifer und Rotschenkel reagierten positiv auf die Einfuhrung der Winteruberflutung, moglicherweise aufgrund der erhohten Verfugbarkeit von Nahrungshabitaten. Sandregenpfeifer konnten ebenfalls eine erhohte Brutplatz-Verfugbarkeit nach der Winteruberflutung erfahren. Die Austernfischer und Sandregenpfeifer waren von der Winterharte beeinflusst, jedoch mit gegenlaufigen Trends. Die Brutvogelzahlen der Austernfischer nahmen nach milden Wintern zu, wahrend die der Sandregenpfeifer abnahmen. Die bleibenden Arten wurden nicht von der Winterharte beeinflusst. Der mogliche Grund dafur wird erortert, indem wir die Brutvogelzahlen der Kiebitze zwischen dem Klydeso Schutzgebiet und dem Tipperne Schutzgebiet im westlichen Danemark vergleichen. Obwohl die Winterharte fur einige der Arten im Klydeso Schutzgebiet keine Wichtigkeit zu haben schien, kann sie immer noch in Gebieten wichtig sein, in denen das Management gleichbleibend ist.

Six species of waterbirds nested colonially on small islands in the Drana saltwater lagoon in the Evros Delta from 1980 to 1986 and in the freshwater lake created in 1989, namely avocet Recurvirostra avosetta, collared pratincole Glareola pratincola, common tern Sterna hirundo, little tern Sterna albifrons, gull-billed tern Sterna nilotica and Mediterranean gull Larus melanocephalus. The favoured islands provided greater isolation, were larger, and had greater cover of plant species preferred by the birds. The most important habitat factor affecting the choice of bird populations in general was isolation of islands. The gradual concentration of most species in the Drana lagoon was due to habitat alteration, predation and disturbance in coastal habitats resulting in scarcity of suitable breeding habitat. The Drana lagoon had a prominent conservation, scientific and economic value and therefore its restoration is recommended by reflooding with sea water, which would better ensure the preservation of the values of the area.

Since 1963 about 270 islands and 40 rafts have been constructed and managed in Britain by the Royal Society for the Protection of Birds, mainly at its wetland reserves. These structures are primarily aimed at providing secure breeding sites for terns, waders, gulls, wildfowl and divers, including nine species of particular conservation importance in Britain. Use of islands and rafts by different breeding species is dependent upon their vegetation cover and geographical location. Bare shingle, or sparsely vegetated islands and rafts, attract the most breeding species in southern coastal locations (up to 20 species), including five species of conservation importance, namely Sandwich tern ( Sterna sandvicensis ), little tern ( Sterna albifrons ), avocet ( Recurvirostra avosetta ) and, occasionally, Mediterranean gull ( Larus melaocephalus ) and roseate tern ( Sterna dougallii ). Similar unvegetated or sparsely vegetated islands on the coast in the north, or inland in the north or south of Britain, support few breeding species, and none of conservation importance. The composition of the bird assemblage breeding on well-vegetated islands and rafts in Britain (up to 20 species) is less influenced by geographical location, but species of conservation importance such as pochard ( Aytha ferina ) are found mainly in the south, and common scoter ( Melanitta nigra ), red-throated diver ( Gavia stellata ) and black-throated diver ( Gavia arctica ) exclusively in Scotland.

Forty-two species of waders, comprising 29 Palearctic migrants, eight residents, two partial migrants and three vagrants, were recorded in three years of montly surveys of shorebirds in coastal Ghana. Eleven species occurred in internationally important populations: curlew sandpiper, little stint, sanderling, spotted redshank, grey plover, ringed plover, black-winged stilt, avocet, black-tailed godwit and turnstone. Arrival of migrant waders in coastal Ghana began in August and reached a peak in November/December. Most waders left the Ghana coast in January, leaving only a small proportion which remained until final departure in April. Another peak in numbers was observed during the spring passage in some years for some wader species. The proportion of migrant wader populations oversummering on the Ghana coast varied with species, and from year to year. While the total populations of some species departed, as much as 30% of the populations of others remained on the Ghana sites during the northern summer. The wader numbers recorded in the different sites and the relative importance of the key sites showed annual fluctuations. Two sites, the Keta and Songaw Lagoons, qualified as internationally important wetlands in terms of their total wader numbers and by virtue of the fact that each supported internationally important populations of seven species of waders. Three other sites also supported internationally important populations: Sakumo Lagoon (4 species), Korle Lagoon (3) and Esiama (1). Two sites, Keta and Korle Laggons, face immediate threat of coastal erosion and/or proposed developments involving drainage and land reclamation. The Sakumo and Songaw Lagoons have great potential for development as conservation areas and proposals have beeb submitted to this effect.

Distribution patterns of Nereis diversicolor and Corophium volutator in the SE-Dollard, a 92 km 2 tidal flat area in the NE Netherlands are described. Body condition as well as the maximal size of juvenile worms correlated positively with elevation of the mudflat, probably caused by a better food supply on the higher mudflats. No spatial variation in size was found for C. volutator . N. diversicolor disappeared from ∼1 km 2 of the intertidal mudflats in the autumn of 1985 as a consequence of the seasonal waste discharges, whereas C. volutator disappeared from an area of ∼4 km 2 . Though the discharges decreased by almost 50% from 1982 to 1985, N. diversicolor disappeared from about the same area in the 2 years. N. diversicolor is the main prey species of the avocet Recurvirostra avosetta , large flocks of which stay in the Dollard during autumn migration. Though the avocets lost ∼30% of their potential feeding area in the Dollard in the 1970s because of the high waste discharges, against only 5 to 10% in 1982 and thereafter (at significant lower discharges), the numbers of the avocets did not respond to the decrease of the discharges.

The concentrations of the principal PCB congeners and the SigmaPCB were determined in eggs of eight species of water birds collected in two areas of the Mediterranean region. The results for SigmaPCB levels indicate statistically significant differences between the species; in the Po delta the higher values are for those species which feed mainly on fish. Differences exist between the congeners and their percentages when compared with the total residue. Tetrachlorobiphenyls constitute a larger proportion of the SigmaPCB in Avocet and Black-winged Stilt, two species whose diet consists mainly of invertebrates. The main component in all the species is 22'44'55' and its presence varies between 11.4% in Avocet and 21.2% in Audouin's Gull. It is suggested that there is a link between the uptake of PCBs and the position of the species in the food chain.