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There is often substantial variation in habitat type and quality within species ranges and management units, especially in wetland ecosystems. This variation necessitates quantifying behavioral and habitat associations to inform conservation of wetland-dependent species. This study explored drivers of American Avocet (Recurvirostra americana) energy expenditure to evaluate patterns of habitat use during the non-breeding season at Mustang Island in Texas, U.S.A. and Rockefeller Wildlife Refuge in Louisiana, U.S.A., on the coast of the Gulf of Mexico. A Bayesian linear mixed model was used to analyze GPS-acceleration data from tracking devices on 31 American Avocets, with overall dynamic body acceleration (a proxy for energy expenditure) as a response variable and tide, time of day, day of year, and landcover as hypothesized drivers. Results suggested that landcover, tide amplitude, and time of day explained substantial variation in energy expenditure, and each site showed unique patterns in these relationships. For example, the interaction of landcover and tide was heavily influential at Rockefeller, whereas Mustang Island birds showed a substantial dichotomy in energy expenditure between day and night. Using energy expenditure to understand habitat associations could be helpful to better understand variation in habitat use and behavior and customize conservation planning in dynamic ecosystems. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Many shorebirds rely on a set of key sites to complete their annual cycles at the flyway, regional, and landscape scales. Coastal wetlands on Chiloé Island, Chile, (Chiloé) support a high proportion of the Hudsonian Godwits (Limosa haemastica) spending the boreal winter along the Pacific coast of the Americas. We conducted annual counts of godwits on Chiloé between 2010 and 2020 to estimate trend in the population. To understand use of individual sites and local networks of sites (clusters), we conducted monthly counts September 2013–March 2014 and September 2017–March 2018. Because of wide variation in annual counts, we did not detect a significant trend in abundance of godwits on Chiloé. Mean monthly abundance summed across all sites during December–February varied markedly among site clusters, with godwits being most abundant in the central Chiloé cluster. Across Chiloé, variation in monthly counts of godwits at individual sites was twice as great as variation in counts summed within a cluster. Casual re-sightings of color-flagged godwits supported the idea that godwits used clusters consistently across years. Our results illustrate the importance of conserving a network of sites across multiple scales as an important step in maintaining Hudsonian Godwit populations. [ABSTRACT FROM AUTHOR]

Millions of wetland-dependent birds annually depend on saline lakes and associated wetlands in the western United States. Understanding the population status and trends of birds with different life histories and habitats can guide efforts to secure water resources needed to sustain bird habitats. We used a 21-year dataset to examine population trends for 24 survey units for migratory shorebirds, waterfowl, and other waterbirds at Great Salt Lake and associated wetlands. We found stable or positive trends for 36 of 37 species or groups in fall, spring, or both seasons when considering survey units in aggregate. Stable, positive, and negative trends were observed in individual survey units. Foraging technique, migration distance, and taxonomic groupings were unrelated to trend direction. Research is needed to test whether survey units represent high-quality habitat. With declining regional water resources, stable and positive aggregate trends reinforce the importance of surveyed units at Great Salt Lake and associated wetlands to wetland-dependent birds. Ensuring continuation of stable and positive trends will require identifying environmental factors—including water quantity and quality—driving trends, and require coordinated regional management and monitoring of wetland-dependent birds. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pheasant-tailed Jacana (Hydrophasianus chirurgus) have a polyandrous mating system, with females defending larger territories within which males compete for and defend smaller territories. The role of the sexes in territorial defense is therefore potentially complex yet remains poorly known. The sex-roles of defensive responses to intruders were monitored at Anawilundawa Ramsar site, North-Western Province, Sri Lanka, where birds encountered conspecifics and other potential predators: Purple Coots (Porphyrio porphyrio), aerial predators, and other waterbirds. Females contributed to defense, though males performed most defense. Females increased their propensity to defend as breeding progressed; by the chick-rearing phase defense was shared more or less equitably between the sexes. Females were more likely to defend against aerial predators than males, and males were more likely to defend against conspecifics than they were to other intruders. When defending against conspecifics, most male defense was directed at intruding males, and most female defense at intruding females. Defense in this polyandrous species relied on cooperation between the sexes but also on some defense specialization whereby females focussed on defending against aerial predators and conspecific females, perhaps because of their larger body size. Both female and male Pheasant-tailed Jacanas therefore contribute to parental care via their defensive activities. [ABSTRACT FROM AUTHOR]

Copyright of Boletin SAO is the property of Sociedad Antioquena de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Understanding space use by endangered species is important for conserving their populations, especially in locations that have a great degree of human activity. Transmitters that provide high spatial resolution have only recently become available for small-bodied animals and show promise for providing new information on habitat use. However, as with any new technology it is important to assess adverse effects on study species. We tested the efficacy of using 1.1-g miniaturized GPS units to document the breeding and post-breeding movements of adult Piping Plovers (Charadrius melodus) from the federally threatened Atlantic Coast population. We also assessed the potential impact of these miniaturized GPS units on nest survival, chick survival, and apparent adult survival rates. We found that Piping Plover movements to and from nesting areas were related to tidal stage, we documented Piping Plovers to be using previously undocumented foraging areas during the breeding season, and we obtained fine resolution habitat use data for two birds on their wintering areas in the Bahamas. The attachment of a GPS tag had no effect on apparent weekly survival of adults, and we found no differences in daily nest survival and chick survival rates between pairs with GPS tags and controls. GPS tags did not appear to adversely impact Piping Plovers during the breeding season, yet lower return rates of GPS tagged birds than controls might suggest potential negative effects on survival. While GPS tags offer a valuable tool to evaluate habitat use of this threatened species on the breeding grounds, long-term tracking needs further investigation. [ABSTRACT FROM AUTHOR]

Although there is a clear link between early arrival on the breeding grounds and fitness in migratory birds, how winter and staging site use influence the timing of migration events prior to arrival at breeding areas is not well established. Therefore, there is a need to characterize the migration phenology of long-distance migratory birds. This study investigated the northbound migration timing of Sanderlings (Calidris alba) along the Central and Mississippi Flyways (i.e., the 'Midcontinental Flyway'). Between 2015 and 2017, coded nanotags were attached to 120 Sanderlings in three staging areas in the USA portion of the Gulf of Mexico: North Padre and Bolivar Flats, Texas and sites in Louisiana. Individuals were then tracked northward using the Motus Wildlife Tracking System. Sanderling detections in more northern latitudes on northward migration were primarily in Saskatchewan (94%; n = 33), with only two individuals detected along the Atlantic coast. Sanderlings trapped in North Padre arrived later in Saskatchewan than individuals trapped in Bolivar Flats and Louisiana. Additionally, there was a negative association between Saskatchewan arrival timing and staging duration, such that later-arriving individuals from North Padre had significantly shorter staging durations and consequently departed from Saskatchewan at the same time as individuals originating from Bolivar Flats and Louisiana. These results provide new insight into the migration schedule of a declining long-distance migratory shorebird species and show how departure and arrival timing are linked across disparate staging sites. [ABSTRACT FROM AUTHOR]

There is limited information about virus epidemiology of shorebirds (family Charadriidae and Scolopacidae) in the East Asia-Australasia flyway. We investigated the prevalence of avian influenza viruses (AIVs) in shorebirds in Hokkaido, Japan, the stopover site of the flyway, to understand the ecology of AIV translocation in the flyway from 2006 to 2010. In total, 1,698 shorebirds belonging to 26 species were captured and released into two different sites using mist nets. Tracheal and cloacal swabs were collected from each bird using cotton swabs. The RNA of influenza A viruses was detected using reverse transcription loop-mediated isothermal amplification. One AIV-positive sample was obtained from a Lesser Sand Plover (Charadrius mongolus) captured in September 2010 at Lake Komuke. Full lengths of hemagglutinin (HA), neuraminidase (NA), polymerase acidic protein, nucleoprotein, matrix protein 1, and nuclear export protein genes were successfully amplified from the AIV-positive sample. All sequences showed the highest identity with sequences obtained from virus strains from Anseriformes species. Shorebirds migrated to Japan 1 mo earlier than did Anseriformes species. Therefore, the Lesser Sand Plover could have been infected by the virus from Anseriformes species on the breeding grounds. The HA sequence showed the highest identity with the H10 sequence whereas the NA sequence exhibited the highest identity with the N7 sequence. Phylogenic analysis showed that the detected subtype H10N7 belongs to the Eurasia lineage and the related strain might have widely spread in Asia in 2009. [ABSTRACT FROM AUTHOR]

While several methods have been employed to estimate shorebird abundance and productivity, little attention has been given to differences in methods used to collect these data. Within central North America, Interior Least Tern (Sternula antillarum athalassos; hereafter, Least Tern) and Piping Plover (Charadrius melodus) monitoring is often accomplished through surveys from a distance or within the nesting colony. Four years (2013-2016) of season-long monitoring (April- mid-September) were implemented from inside and outside nesting colonies at off-channel nesting sites along the central Platte River, Nebraska, USA to compare estimates of resulting productivity components. Each method was found to have observational strengths and weaknesses, depending on the species and reproductive component. Outside Least Tern monitoring resulted in higher fledgling counts (256 total fledglings) and lower breeding pair estimates (242 total pairs), resulting in higher fledge ratios compared to inside monitoring (192 total fledglings, 261 total pairs). Differences in Piping Plover fledge ratios were annually variable (total pairs: inside estimate = 116, outside estimate = 103; total fledglings: inside estimate = 142, outside estimate = 117). Overall, both inside and outside monitoring can produce reasonable estimates of species abundance and productivity despite substantial differences in monitoring effort and cost. [ABSTRACT FROM AUTHOR]

Technologies for remotely observing animal movements have advanced rapidly in the past decade. In recent years, Australia has invested in an Integrated Marine Ocean Tracking (IMOS) system, a land ecosystem observatory (TERN), and an Australian Acoustic Observatory (A2O), but has not established movement tracking systems for individual terrestrial animals across land and along coastlines. Here, we make the case that the Motus Wildlife Tracking System, an open-source, rapidly expanding cooperative automated radio-tracking global network (Motus, https://motus.org) provides an unprecedented opportunity to build an affordable and proven infrastructure that will boost wildlife biology research and connect Australian researchers domestically and with international wildlife research. We briefly describe the system conceptually and technologically, then present the unique strengths of Motus, how Motus can complement and expand existing and emerging animal tracking systems, and how the Motus framework provides a much-needed central repository and impetus for archiving and sharing animal telemetry data. We propose ways to overcome the unique challenges posed by Australia's ecological attributes and the size of its scientific community. Open source, inherently cooperative and flexible, Motus provides a unique opportunity to leverage individual research effort into a larger collaborative achievement, thereby expanding the scale and scope of individual projects, while maximising the outcomes of scant research and conservation funding. [ABSTRACT FROM AUTHOR]

Supernormal clutches are found across bird species. Such clutches often result from more than one female laying eggs in the same nest and can reflect different behaviours from parasitism to laying mistakes. Enlarged clutches are readily visible among waders due to a maximum maternal clutch size of four eggs, yet surprisingly little is known about this phenomenon. Since supernormal clutches are rare, large sample sizes are required to reliably quantify their natural frequencies. We used a large dataset to estimate the frequency of supernormal clutches in the polygamous Temminck's Stint Calidris temminckii and the monogamous Southern Dunlin C. alpina schinzii, and examine the timing of supernormal clutches in relation to the general distribution of nest initiation dates. While supernormal clutches were very rare, they were over four times more common in the Temminck's Stint (0.50%, n = 1594) than in the Southern Dunlin (0.11%, n = 2766). Dunlin show among the lowest frequency of supernormal clutches reported for waders. In the Temminck's Stint, supernormal clutches were found in the middle of the season, while in the Southern Dunlin such clutches occurred in late season replacement nests. The higher rate and timing of enlarged clutches in Temminck's Stints probably relates to the lspecies' breeding system, which can include simultaneous courtship of multiple partners, but more work is needed to assess the relative influence of different factors. We argue that intraspecific nest parasitism is unlikely to be a primary reproductive tactic in small sandpipers. [ABSTRACT FROM AUTHOR]

Efficient fuelling is essential for migratory birds because fuel loads and fuelling rates affect individual fitness and survival during migration. Many migrant shorebirds are exposed to oil pollution and its toxic constituents, polycyclic aromatic hydrocarbons (PAHs), at migratory staging sites, which has the potential to interfere with avian refuelling physiology. In this study, we orally dosed shorebirds with environmentally-relevant PAH mixtures to simulate dietary exposure during staging. Forty-nine wild-caught Sanderling ( Calidris alba ) were exposed to 0 (control), 12.6 (low), 126 (medium), or 1260 (high) μg total PAH/kg body weight/day. Birds were dosed during a 21-day period of autumn pre-migratory fuelling to mimic the typical staging duration of Sanderling. We measured daily changes in mass and fat loads, as well as ethoxyresorufin- O -deethylase (EROD) activity, serum biochemical profiles, and liver mass and lipid content following dosing. All dose groups gained fat and increased in mass (size-corrected) during the study period, with females having a higher average body mass than males. However, mass gain was 3.9, 5.4, and 3.8 times lower in the low, medium, and high dose groups, respectively, relative to controls, and body mass in the medium and high dose groups significantly declined near the end of the experiment. EROD activity showed a dose-dependent increase and was significantly elevated in the high dose group relative to controls. Higher individual EROD activity was associated with reduced serum bile acid and elevated serum creatine kinase concentrations in both sexes, and with elevated serum lipase concentrations in females. These results suggest that PAH exposure in Sanderling can interfere with mechanisms of lipid transport and metabolism, can cause muscle damage, and can lead to reduced overall fat loads that are critical to staging duration, departure decisions, migratory speed, and flight range. Given that many shorebirds migrate thousands of kilometers between the breeding and wintering grounds and frequently aggregate at key staging sites that are subject to contamination, PAH exposure likely represents a significant threat to shorebird migratory success. [ABSTRACT FROM AUTHOR]

Abstract: Over 50% of Western Hemisphere shorebird species are in decline due to ongoing habitat loss and degradation. In some regions of high wetland loss, shorebirds are heavily reliant on a core network of remaining human‐managed wetlands during migration journeys in the spring and fall. While most refuges have been designed and managed to match the habitat needs of waterfowl, shorebirds typically require much shallower water (<10 cm deep). Traditional static habitat modeling approaches at relatively coarse spatial and temporal resolution are insufficient to capture dynamic changes within this narrow water depth range. Our objectives were to (1) develop a method to quantify shallow water habitat distributions in inland non‐tidal wetlands, and (2) to assess how water management practices affect the amount of shorebird habitat in Sacramento National Wildlife Refuge Complex. We produced water depth distributions and modeled optimal habitat (<10 cm deep) within 23 managed wetlands using high‐resolution topography and fixed‐point water depth records. We also demonstrated that habitat availability, specifically suitable water depth ranges, can be tracked from satellite imagery and high‐resolution topography. We found that wetlands with lower topographic roughness may have a higher potential to provide shorebird habitat and that strategically reducing water levels could increase habitat extent. Over 50% of the wetlands measured provided optimal habitat across <10% of their area at the peak of migration in early April, and most provided a brief duration of shallow water habitat. Reducing water volumes could increase the proportion of optimal habitat by 1–1,678% (mean = 294%) compared to actual volumes measured at peak spring migration in 2016. For wetlands with a high habitat potential, beginning wetland drawdown earlier and extending drawdown time could dramatically improve habitat conditions at the peak of shorebird migration. Our approach can be adapted to track dynamic hydrologic changes at broader spatial scales as additional high‐resolution topographic (e.g., lidar, drone imagery photogrammetry) and optical remote sensing data (e.g., planet imagery, drone photography) become available. [ABSTRACT FROM AUTHOR]

Piping Plovers ( Charadrius melodus) undertake comparatively short migrations for a shorebird and were not previously thought to congregate in large numbers during migration. Superpopulation size (individuals occurring at the study site during the study period) and stopover duration were estimated for migratory Piping Plovers on South Point, Ocracoke Island, North Carolina, USA, from 3 July-28 October 2016 by integrating a Jolly-Seber model and a binomial model of resighting and count data. We estimated 569 Piping Plovers (95% CI: 502-651) used South Point during fall migration in 2016, approximately 10% of the global population and approximately 15% of the Atlantic Coast population. Stopover duration differed between Piping Plovers that bred on or near our study site (Southern USA, 46 days, SD = 1.7) compared to individuals that bred in the northern area of the breeding range (Atlantic Canada, 41 days, SD = 2.0; New England States, USA, 44 days, SD = 1.8) and the central area of the breeding range (New York and New Jersey, USA, 26 days, SD = 1.4). South Point may be unique in that no other areas are known to host similar numbers of Piping Plovers during fall migration. [ABSTRACT FROM AUTHOR]

Many bird species of conservation concern have behavioral or morphological traits that make it difficult for researchers to determine if the birds have been uniquely marked. Those traits can also increase the difficulty for researchers to decipher those markers. As a result, it is a priority for field biologists to develop time- and cost-efficient methods to resight uniquely marked individuals, especially when efforts are spread across multiple States and study areas. The Interior Least Tern ( Sternula antillarum athalassos) is one such difficult-to-resight species; its tendency to mob perceived threats, such as observing researchers, makes resighting marked individuals difficult without physical recapture. During 2015, uniquely marked adult Interior Least Terns were resighted and identified by small, inexpensive, high-definition portable video cameras deployed for 29-min periods adjacent to nests. Interior Least Tern individuals were uniquely identified 84% (n = 277) of the time. This method also provided the ability to link individually marked adults to a specific nest, which can aid in generational studies and understanding heritability for difficult-to-resight species. Mark-recapture studies on such species may be prone to sparse encounter data that can result in imprecise or biased demographic estimates and ultimately flawed inferences. High-definition video cameras may prove to be a robust method for generating reliable demographic estimates. [ABSTRACT FROM AUTHOR]

Copyright of Avian Diseases is the property of American Association of Avian Pathologists, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Historically, the land-based threat to shorebird colonies on Phillip Island, Victoria, Australia, was fox predation. As a result, a fox eradication programme consisting of three phases: knock-down (i.e., 2006), clean-up (i.e., 2011), and post-eradication. In 2011 an effective knock-down was declared, signalling the beginning of the clean-up phase. The purpose of this research is to assess the recovery of six resident shorebird species on Phillip Island following fox removal. The statistical methodologies used are novel for assessing bird species population recovery following a successful predator eradication program. We used citizen science data from 2003 to 2017, extracted from the Atlas of Living Australia. The first analysis method used INLA modelling, which relied on a Negative Binomial distribution for bird counts to look for upward trends in shorebird populations during the fox eradication operation. The second method use changepoint analysis techniques to see whether successive phases of the eradication process were associated with changes in bird population numbers. Four of the six shorebird species investigated responded positively to reduced fox populations over the 15-year study, and all changepoint approaches consistently recognised the start of the clean-up phase, with less consistency identifying the start of the knock-down phase. Since 2006, the INLA models indicate a significant increase in the upward trend of shorebird populations for three of the six shorebird species investigated. Agreement across the four changepoint techniques indicates that changes in bird numbers were associated with the date of the eradication program's clean-up phase for all of these shorebird species. These results demonstrate some promise for these methods to monitor native species recovery during eradication programs. [ABSTRACT FROM AUTHOR]

Male and female Dunlin ( Calidris alpina) exhibit slight plumage and structural differences. Discriminant function analysis based on morphological characteristics can effectively differentiate between sexes in several subspecies of Dunlin. We assessed the level of sexual size dimorphism in a subspecies that breeds in sub-Arctic Canada ( C. a. hudsonia), and used discriminant function analysis to create equations to classify individuals to sex using five body measurements (body mass, head length, culmen length, tarsus length, and flattened wing chord). Females were significantly larger than males for all body measurements. Discriminant function analysis using tarsus length, head length, and body mass correctly classified 87.1% of molecularly sexed females ( n = 31) and 92.6% of males ( n = 27). The classification of an independent sample ( n = 12) resulted in 100.0% correct assignment of sex with 33.3% of individuals falling within the undetermined range. A discriminant function analysis equation is provided for use with non-breeding populations using only structural characteristics with classification accuracies of 83.9% for females and 81.5% for males. The resulting equations from this study have classification accuracies comparable to those equations developed for other Dunlin subspecies and can be used to reliably differentiate sexes of C. a. hudsonia using body measurements collected in the field. [ABSTRACT FROM AUTHOR]

The article discusses a research study about the influence of declining nest survival on the decline in the population of Snowy Plover at Great Salt Lake in Utah. Topics cited include the identification of nest survival, nesting substrate, the impact of predation, weather, and abandonment on daily nest survival rates, and the disadvantage of dikes as nesting habitat.

The bush stone-curlew Burhinus grallarius is listed as 'Near threatened' on the IUCN Red List of Threatened Species. In NSW, bush stone-curlews are listed as 'Endangered' under the Threatened Species Conservation Act 1995. The present study focused on bush stone-curlew populations throughout the central coast of NSW and the aim of this study was to develop an inductive spatial model in Geographical Information System (GIS) of suitable bush stone-curlew habitat based on historical sightings and empirical data. To develop the models, micro-habitat data from 30 sites where bush stone-curlews have been recorded were combined with broad historical habitat maps between Gosford and Port Stephens. The habitat data and developed spatial models indicated that bush stonecurlew sightings are associated with trees dominated by Casuarina glauca and Syncarpia glomulifera. In terms of broad habitat classifications, bush stone-curlews are more likely to be sighted in wet sclerophyll forests (towards Gosford) and dry sclerophyll forests and saline wetlands (Port Stephens). The spatial model developed for this endangered bird will help direct conservation efforts to maintain and promote habitat in areas where urban development is rapidly increasing. [ABSTRACT FROM AUTHOR]

The article presents a study on nest survival and productivity of the Snowy Plover or Charadrius nivosus nesting on ocean-fronting beaches in northern California. It is said that plovers select sites that are different from the surrounding landscapes. Results show that daily nest survival is higher at the southern sites as compared to the northern sites where human and corvid activity is higher. Factors that affect plover reproductive success include land use and human and predator activity.

The article presents a study on trapping methods for ground-nesting Snowy Plovers. It notes that Snowy Plovers are a species of conservation concern by the U.S. Fish and Wildlife Service (USFWS). It concludes that the funnel trap has the lowest total time at the nest, highest capture rate and lowest disturbance to nest areas which should allow researchers to better study this species.

The article presents a study which examined temporal avian influenza virus (AIV) prevalence trends in four Charadriiformes species, namely, Ruddy turnstones, Red knots, Sanderlings and Laughing gulls during the spring migratory stopover at Delaware Bay. Serial cross-sectional data from 2000 through 2008 and generalized linear and additive models were utilized. Only Sanderlings exhibited dynamical changes in AIV prevalence over the stopover period.

The article presents a study that determines the orientation and routes taken by arctic shorebirds during autumn migration in southern Sweden. The study uses three approaches such as visual telescope, tracking radar, and ring recoveries to accurately evaluate the orientation changes in different sites. Results of the study indicate that the gradual change cannot be explained by different wind conditions or by distinct responses to specific topographical features. Study findings suggest that shorebirds have travel within the winding fight corridor in broad agreement with the large-scale topology.

The article focuses on the population trends in Semipalmated Sandpipers. Data from the Ontario Shorebird Surveys and the Quebec Checklist collected between 1974-1998 showed negative trends in the shorebird's population. Analyses of population trends with migration monitoring data from eastern and central North America were conducted from 1974-2009. Declines in Ontario amounted to an estimated eight percent per year from 1974-2009.

This article presents a study on the use of a population model for Piping Plover to maximize the value of the data from Barber et al. for conservation of the species in North America. Barber et al. used direct quantifications of the effect of specific conservation efforts, given that demographic data for endangered species are rare and often imprecise. Their data shows a trade-off between increased productivity and reduced adult survival.

The article discusses a study conducted on the foraging behavior of Red Knots during their spring stopover at Virginia. It was determined that the knots have to feed on mollusks day and night to gain enough body mass and energy to be able to complete their migration. This contrasts with knots needing to feed on Horseshoe Crab eggs only during the day at nearby Delaware Bay. It is concluded that the Red Knot recovery efforts require the preservation of the Atlantic coast stopover sites.

The article presents a study which monitored southward migrating Red Knots in Cape Cod, Massachusetts. It was observed that northern and southern-marked knots had different migration chronologies, plumage characteristics and flight feather molt. It was also noted that the average minimum stopover durations were found to differ according to original banding locations and that differential uses of foraging and roosting habitats were related to migration destinations.

The article discusses the management of rice fields for birds during the non-growing season. Several management actions have been identified that could provide conservation benefits to birds in rice fields without grossly affecting crop production. These actions that can affect bird populations include method of harvest, winter flooding, and food supplementation. On the other hand, methods of field preparation, organic farming, and management of field surroundings are factors that help conserve rice lands.

This article discusses a study which investigated the potential of low pathogenicity (LP) avian influenza virus (AIV) isolates of wild bird origin to establish infection in commercial turkeys and broiler chickens. Researchers recovered isolates in 2005 and 2006 from waterfowl and shorebirds in the Delmarva Peninsula region of the east coast of the U.S. They discovered that the LP AIV isolates were pathogenic for two-week-old meat-type turkeys and broiler chickens. The methodology of the study are detailed.

The article offers information on a study which explored the prevalence of avian influenza in migrating birds in Taiwan from 1998 to 2007. During the period, 29,287 samples of avian influenza virus (AIV) were collected from wild ducks, shorebirds and other wild birds in the wetlands around Taiwan and outside the Penghu and Kinmen islets. Hemagglutination and reverse transcription polymerase chain reaction (PCR) were utilized to identify AIV in the allantoic fluid. Study authors found that the prevalence of AIV in Taiwan is lower than in Europe and America, which is speculated to be due to the high air temperature in Taiwan.

The article discusses a study which examined Piping Plover foraging-site selection during the breeding season on the Missouri River and investigated the relationship between site selection and invertebrate abundance indices within habitats. Results showed that there is no difference in invertebrate biomass and the numbers along exposed shoreline. Meanwhile, invertebrate biomass and numbers on the epilimnetic river reach were higher along the protected shoreline than on the main channel shoreline. Furthermore, invertebrate numbers were higher in saturated and moist habitats than in vegetative areas.

The article discusses a study which investigated breeding stage influences space use of female American avocets in San Francisco Bay, California. The researchers used Hawth's Tools for ArcGIS to calculate the liner distance between consecutive locations for radio-marked avocets. It was found that linear movements, home ranges, core areas, and distances from nest were greater in the post-breeding and pre-incubation stages than during the incubation and brood-rearing stages. A map is presented showing dominant habitat types.

The goal of this study was to determine how digital photogrammetry can be used to describe and monitor shorebird habitat. Methods previously used for monitoring beach erosion were applied to shorebird habitat, concentrating on the requirements of Western Snowy Plovers. How the physical habitat of Western Snowy Plovers has changed over time was investigated at Sand Beach, which is part of Coal Oil Point Reserve in Santa Barbara, California, from 1928 to 2004, using width, area, and elevation data gathered from a series of aerial photographs. Single georeferenced photographs were used to measure width at regular intervals and area for each year a photo was available. Georeferenced aerial photographs can be used to obtain accurate measurements 01 beach area and width. Orthorectification is not necessary if photos can be georeferenced with minimal error. Sands Beach was found to be increasing in area. This was due mainly to the retreat of the vegetation line as the mouth of Devereux Slough shifted in 1992 rather than an accumulation of sand on the beach. [ABSTRACT FROM AUTHOR]

This article focuses on the spatial patterns of organisms on the landscape, which is of central importance to ecology and conservation. Spatial pattern, or dispersion, refers to the spatial composition of organisms on the landscape, that is, the relative proportion of organisms distributed among a number of habitat patches or sites. Abiotic and biotic factors, including habitat availability, abundance of resources, and species interactions, are important determinants of dispersion. However, species' responses to these factors are quite variable, so that spatial patterns found in nature are often heterogeneous. For instance, shorebirds show diverse migratory strategies, which result in variable spatial patterns of habitat use at the landscape scale. Some species fly moderate distances each time they move, stopping to feed opportunistically in small numbers at wetland sites encountered at the end of each migratory movement. Others make marathon flights, stopping at a few, traditionally used wetlands where they concentrate in huge numbers.

We examined the efficacy of habitat creation for shorebirds on reclaimed land in Osaka Port. The Wild Bird Park was laid out on a reclaimed land in Osaka Port in 1983. A modern history of the area as a habitat for shorebirds can be divided into four stages. First, many shorebirds visited the tidal flat of 30 ha that emerged on the south part of the Sakishima, which had been reclaimed from the sea in 1941, but was abandoned between 1950 and 1958 [Notes on Osaka Bay Waders. Private Publishing (in Japanese with English abstract)]. Second, the tidal flat disappeared because of the start of the reclamation of the north part of Sakishima in 1958, and a salt marsh of 85 ha emerged in the north part between 1974 and 1982. Third, the salt marsh disappeared due to the construction and the Wild Bird Park was opened on a part of the salt marsh in 1983. The park had a planted area of 6.5 ha and a sandy area of 12.8 ha, which included two ponds and a lagoon. Fourth, one of the ponds was restored to a tidal flat in 1995 after consultation among the manager, NPO, and scientist as a result of the monitoring. The area of tidal flat increased from 0.2 to 2.6 ha, and the number of shorebirds increased from 205 (the average of 1991–1995) to 1042 (1996). The abundance and species richness of shorebirds is equivalent to those at the first stage (1950s). The species composition of benthic animals had also changed; the dominant group was Chironomid larvae during the second and third stages and Polychaetes during the fourth stage, and the species richness was greatest at the fourth stage. However, the tidal flat of the park had fewer brachyurans and mollusks than natural tidal flats in Japan. This might result in a lower abundance of large sandpipers at the fourth stage compared with that at the first and second stages. [Copyright &y& Elsevier]

Many countries, including China, have increased new areas of mangrove plantations to reverse the decline in mangrove ecosystem functions. However, this has led to the intrusion of mangroves into many tidal flat areas, which are important habitats for shorebirds. A reduction in the available tidal flat areas will reduce the diversity of shorebirds, therefore bringing mangrove conservation into conflict with shorebird conservation. In fact, a certain area of mangroves is an indispensable element of shorebird habitat. Therefore, this study proposes the maintenance of a ratio between the area of tidal flats and the area of mangroves within a mangrove ecosystem which is optimal for both mangrove conservation and shorebird conservation. This study recorded data for shorebird distribution, areas of mangrove and tidal flats, and other relevant data for Guangdong Province, China. The ratios of tidal flat areas to mangrove areas within mangrove ecosystems were established and a mathematical model was applied to establish the relationship between shorebird diversity and abundance and the ratios of tidal flat areas to mangrove areas. The results showed that: (1) there was no significant correlation between mangrove area and shorebird richness (r = 0.176, p = 0.230)and abundance(r = 0.104,p = 0.481), whereas there was no significant correlation between tidal flat area and shorebird richness(r = 0.153, p = 0.299)and abundance(r = −0.063,p = 0.670); (2) the relationship between the ratios of tidal flats area to mangrove area [ x ] and shorebird richness [ f(x) ] and abundance [ g(x) ] satisfied the cubic function equation f(x) = 0.106 x 3 − 2.147 x 2 + 11.269 x (0.0265≤x ≤ 13.8100) (R2 = 0.714, P = 0.000), g (x) = 0.008 x 3 − 0.189 x 2 + 1.124 x (0.0265≤ x ≤ 13.8100) (R2 = 0.713, P = 0.000) ; (3) the appropriate value of x is 3.5662or 3.9785, and maintaining this ratio can reduce the conflict between mangrove conservation and shorebird conservation and promote the sustainable development of the mangrove ecosystem. This information can contribute to the sustainable development of mangrove planting management strategies at various scales and will be invaluable in assessing the effectiveness of existing mangrove management approaches. [ABSTRACT FROM AUTHOR]

Beach-nesting shorebirds are declining due, in part, to human disturbance in nesting areas. Sign-posts are installed around nesting areas to protect nests from people, but they may serve as perches and attract avian predators. From March–August 2018, we used passive infrared game cameras to monitor perching activity on 15 variations of sign-post designs on 2 barrier islands in North Carolina. We observed 110 independent perching events dominated (70%) by common (Quiscalus quiscula) and boat-tailed grackles (Quiscalus major) and laughing gulls (25%; Leucophaeus atricilla). We compared how the number of days perching occurred was associated with sign shape, material, sign-construction (sign x shape), position on post, and presence/absence of a nail on top of the post. Position of the sign on the post had the strongest effect on the number of days perching events occurred (χ2 = 18.62 df = 2 P < 0.001). Signs positioned flush with the top of the post were most frequently perched on (10% of perching days), followed by signs positioned lower (5%) and higher (2%) than the post top. The frequency of avian predators perching on triangular signs (8%) and rectangular signs (5%) did not differ (X2 = 2.89 df = 1 P = 0.11). While sign material (metal: 12%; laminated cardboard: 11%; plastic: 13%) did not affect the probability of perching (χ2 = 1.06 df = 2 P = 0.58), triangular plastic signs (11%) had more (χ2 = 6.011 df = 2 P = 0.05) perching activity than rectangle-metal (6%) and rectangle-laminated signs (6%). Presence (3%) or absence (4%) of a nail on top of posts did not affect the number of days perching occurred on a sign-post (χ2 = 0.59 df = 1 P = 0.52). We recommend managers position signs high on the post to reduce occurrences of predatory perching. If a choice of sign shape and material is available, rectangular metal or laminated cardboard signs may also reduce perching activity. Image 1 • Design variables: sign shape, material, sign-construction, position on post, nails. • 110 independent perching events dominated by 3 species. • Position of sign on post had strongest effect on perching activity. • Rectangular metal or laminated cardboard signs may also reduce perching activity. [ABSTRACT FROM AUTHOR]

Land-claim and human disturbance are major threats to shorebird population declines along the East Asian–Australasian Flyway. When existing tidal flats undergo greater anthropogenic disturbance from intensive urbanization, newly-formed tidal flats may provide alternative habitats for shorebirds. Knowledge of the key habitat factor influencing shorebirds communities is essential for tidal flat restoration and management, especially on intensively urbanized coasts. We compared the differences between old and newly-formed tidal flats in terms of habitat characteristics and shorebird communities, analyzed the influence of habitat metrics on shorebird species abundance and feeding strategies in Macao, China, from 2006 to 2009. Habitat characteristics and shorebird communities were significantly different between old and newly-formed tidal flats which represented different urbanization level. The greatest difference of shorebird communities between two tideland types occurred in winter. Artificial shoreline rather than high rise buildings had direct and negative impact on shorebird communities. The habitat factors relieved shorebirds from surrounding urbanized environment were vegetation coverage within tidal flat and adjacent grassland areas. Under the pressure of rapid urbanization, the newly-formed tidal flat, which had more natural boundaries, adequate vegetation coverage and extensive adjacent undisturbed grassland, provided more suitable habitat than old tidal flats for shorebirds in Macao. Conservation efforts for shorebirds should primary focus on maintaining the extent of current tidal flats, with emphasized management on reducing anthropogenic disturbance around tidal flats. Image 1 • Habitat characteristics affecting shorebird distributions were identified. • Newly formed wetlands supported more diversified and abundant shorebirds. • Vegetation and grassland may be the shelter from human disturbance, while artificial shoreline has direct negative impact. • Divergence in seasons and migratory status were responsible for habitat selection. [ABSTRACT FROM AUTHOR]

Because scant information exists on the distribution, abundance, andhabitat use of shorebirds nesting in the National Petroleum Reserve-Alaska, we determined nest densities of shorebirds in tundra habitatsat Inigok, Alaska. We searched for shorebird nests on 29 plots (4 haeach) between 10 June and 18 July 1998 and surveyed for plover pairson a 12.8-km2 plot. Thirteen shorebird species bred at Inigok, and nest density was highest in drained-lake basins (mean = 80.0 nests/km2). Semipalmated Sandpipers (Calidris pusilla) and Pectoral Sandpipers (C. melauotos) were the most abundant shorebirds breeding at Inigok and nested exclusively in drained-lake basins (mean = 30.0 nests/km2 each). Only American Golden-Plovers (Pluvialis dominica) nested in appreciable numbers (2.57 pairs/km2 on a single plot) in tussock/ridge tundra. Although constituting a relatively small proportion of the tundra at Inigok (10.5%), drained-lake basins supported a disproportionate number of breeding species and individuals and may support sizable portions of the populations of Semipalmated Sandpipers and Pectoral Sandpipers breeding on the North Slope. Development plans for inland sites on the North Slopeshould consider the importance of drained-lake basins to nesting shorebirds. [ABSTRACT FROM AUTHOR]

Colonization of a recreated area of intertidal land by marine invertebrates and their bird predators was studied from April 1993 to August 1997. The most important food of large shorebirds, the ragworm Nereis diversicolor, did not reappear until late summer 1995 and did not become abundant until the following autumn. Annual attempts at colonization by the crustacean Corophium volutator, the main food of several small shorebird species, failed until summer 1996 when animals survived through the subsequent winter for the first time. Colonization by the mud-snail Hydrobia ulvae took place a year after flooding of the site, but densities in 1997 were still well below those found elsewhere on the adjacent estuary. The delay in successful colonization by Nereis and Corophium may be attributable in part to the compaction of the intertidal muds caused by the earthmoving equipment used to contour the site. The slow increase in Hydrobia density may be a consequence of low organic content of the mud. Bird use is concentrated chiefly during the hours when the adjacent estuarine mudflats (with unrestricted tidal flow) are covered by the tide, since the new site thenprovides a supplementary feeding area. Peak daytime usage occurs during the migratory passage periods when birds need to feed for longer periods than usual, in order to refuel for their migrations; high usage is also anticipated in cold winters. On this evidence, creation of intertidal areas in mitigation for any lost nearby to industrial orother development should take place at least three years before the losses, in order to make the new areas profitable for feeding waterfowl. [ABSTRACT FROM AUTHOR]

The winter distribution of common shorebirds and songbirds in farmlands on the Fraser River delta, British Columbia, is described for 1989-1991. Most Dunlin (Calidris alpina) and Black-bellied Plovers (Pluvialis squatarola) roosted in large flocks (median=6450 birds) on beaches during high tides. Smaller flocks (median=507 birds) that flew tofarmlands settled in ploughed fields, turf grass and pasture within 2 km of Boundary Bay. Dunlin and Black-bellied Plovers that flew to farmlands mostly foraged there between November and March. The seasonal use of farmlands by Dunlins is probably a trade off between food energy requirements and predation risk from falcons. Forty-five speciesof songbirds were recorded in farmland hedgerows. Song Sparrow (Melospiza melodica), American Robin (Turdus migratorius), White-crowned Sparrow (Zonotrichia leucophrys), and European Starling (Sturnus vulgaris) accounted for over two-thirds of all birds recorded. Shrub hedgerows supported 30 species with a mean of 7.9 individuals detected percensus stop versus 40 species with a mean of 18.0 individuals per census stop in tree-hedgerows. [ABSTRACT FROM AUTHOR]

No abstract. [ABSTRACT FROM AUTHOR]