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Abstract Developing effective monitoring techniques for sensitive wildlife populations is essential for improving conservation outcomes. The American woodcock (Scolopax minor; hereafter woodcock) is an upland migratory game bird traditionally surveyed by documenting displaying males in spring. Surveys of displaying males are limiting in a variety of important ways such as brief detection window and male‐centric observations. Thermal technology may overcome limitations of traditional monitoring techniques by increasing detections of non‐singing woodcock, however, the efficacy of thermal imaging for detecting woodcock remains unknown. To quantify woodcock detection probability using thermal imaging, we deployed and searched for heat‐emitting woodcock mounts along transects within early‐successional habitats in central Pennsylvania during 2020. We deployed 110 woodcock mounts and successfully detected 63 (57.2%). Detection rate declined as a function of increasing vegetation density and distance from transect. Although detection probability of woodcock was imperfect, thermal cameras may provide a solution for researchers aiming to assess presence or density of woodcock when coupled with analytical methods that account for imperfect detection.

How postbreeding habitat quality and body composition of migratory birds carry over to influence fall migration strategies and residency merits consideration when creating cross-seasonal conservation plans, especially in breeding populations that are partial migrants. We assessed the influence of postbreeding habitat quality on departure body composition and fall migration patterns in a southern New England breeding population of American Woodcock (Scolopax minor). Woodcock that overwintered near breeding areas (n = 5) had less fat upon capture in fall and used lower quality habitat during the fall than birds that eventually departed on migration (n = 17). Woodcock that departed earlier were long-distance migrants that had inhabited higher quality landscapes prior to migration, departed with less or similar fat stores, stopped over for shorter periods on migration, and arrived earlier on their more southerly wintering areas. In contrast, woodcock that departed later were short-distance migrants that had inhabited lower quality landscapes prior to migration yet stored similar or more fat upon departure, stopped over for longer periods on migration, and arrived relatively late to their more northerly wintering areas. These differences in migration strategies were evident under the same fall environmental conditions and did not appear related to individuals responding to their own condition as would be expected if they were classic condition-based carry-over effects. As such, the southern New England breeding population of woodcock is best categorized as nonfacultative partial migrants (i.e., includes residents, short-distance migrants, and long-distance migrants) that demonstrate weak connectivity between life stages; such populations are excellent for the study of the costs and benefits of migration. The stopover and wintering areas used by woodcock in the coastal mid-Atlantic states deserve conservation and management attention in order to preserve critical habitat throughout their wintering range. [ABSTRACT FROM AUTHOR]

American woodcock Scolopax minor (hereafter woodcock) migration ecology is poorly understood, but has implications for population ecology and management, especially related to harvest. To describe woodcock migration patterns and phenology, we captured and equipped 73 woodcock with satellite tracking devices in the Central Management Region (analogous to the Mississippi Flyway) of North America and documented migration paths of 60 individual woodcock and 87 autumn or spring woodcock migrations during 2014-2016. Woodcock migration at the scale of the Central Management Region was more synchronous in spring than in autumn, but unlike most other migratory birds, average duration of autumn migration (31 days) was shorter than duration of spring migration (53 days). This difference in migration duration resulted from woodcock making more close-together migratory stopovers during spring migration, not because woodcock had individual stopovers of longer duration. During autumn migration, the number of days, the number of stopovers, migration end date and net migration displacement were negatively related to initiation date and rate of migration, and the number of stopovers and the net migration displacement were negatively related with migration end date. Spring migration duration, end date, the number of stopovers and net migration displacement were negatively related to migration rate and initiation date was positively related to migration rate, suggesting that woodcock that initiated spring migration later had faster migration rates. Juvenile female woodcock began spring migration later than adult female woodcock. Our results provide a basis for comparing current harvest seasons with presence of migrating woodcock during autumn and provide insight into differential harvest of migratory versus local woodcock on breeding areas. [ABSTRACT FROM AUTHOR]

Abstract 1. Habitat loss and degradation are contributing to severe declines in many North American bird species. For American woodcock Scolopax minor (‘woodcock’), loss of preferred young forest habitat matrices are generally attributed as the primary drivers of range‐wide population declines in eastern North America, but regional patterns in abundance or habitat availability have not been assessed in Nova Scotia, the northeastern‐most portion of the range. 2. Our objectives were to (a) identify regions of similar trends over the past five decades, (b) evaluate spatiotemporal relationships in the effect of habitat availability on abundance across the province and (c) provide recommendations for woodcock management priorities in Nova Scotia to target local population declines. 3. Using 50 years of standardised surveys and habitat measures, we investigated woodcock population trends and local habitat availability by applying a novel spatially‐explicit model with Integrated Nested Laplace Approximation. 4. Province‐level declines were primarily driven by losses of breeding woodcock in the north and south of the province, while the central region experienced growth. The proportion of area around a survey route comprised of clear‐cut, harvested forest was the most important habitat feature of nine potential explanatory variables to affect abundance, where higher levels of clear‐cut area predicted higher abundance, particularly in the last 15 years (increase from two to 10 birds on average as the amount of clear‐cut area increased from zero to 28%). 5. Historically, habitat for species requiring open areas and regenerating forests would be established through periodic natural disturbance. Today, it is impractical for these processes to occur unimpeded, thus commercial timber harvests and proactive habitat management are necessary to ensure habitat availability. For woodcock in Nova Scotia, partnering with both the local forest products industry and wider national and international habitat management initiatives to provide habitat in the southern and northern regions of the province could be key to improving the population status both locally and ultimately range wide. The temporally and spatially extensive surveys used here provide a remarkably comprehensive avian monitoring dataset. Coupled with modern analytical tools, our study system serves as an example of how long‐term avian survey efforts are capable of informing management regionally to achieve broader conservation targets.

Weather appears to influence collisions of migratory birds with human-built structures including buildings, but formal analyses are lacking. In 2018, as part of a two-year study at 21 buildings in Minneapolis, Minnesota, USA, we observed a large number of American woodcock Scolopax minor collisions during two early spring snowstorms. We describe these events, analyze associations between weather and woodcock collisions during spring 2018, and compare observations to past studies across the woodcock's range. Most spring 2018 woodcock collisions (11 of 15; 73.3%) occurred in association with the two snowstorms. Analyses indicated collisions were positively associated with maximum and average wind speeds the night before collision surveys, and most collisions occurred with north winds. Collisions also increased with lower cloud base height two nights before surveys. These results support that woodcock collisions were greatly influenced by inclement weather, specifically the coincidence of strong north wind and low clouds. Comparing results to past studies illustrates that building collisions could be a major range-wide source of woodcock mortality, especially in spring migration when mortality is likely additive. Although more research is needed to understand range-wide, population-level effects of woodcock collisions, management to reduce building collisions during migration may benefit woodcock populations. Additional research is needed to clarify effects of weather on bird collisions because management efforts could be refined if collisions of woodcocks and other bird species were forecastable like the weather. [ABSTRACT FROM AUTHOR]

In this study, we examined the variation of eight autosomal microsatellite markers, and explored the genetic diversity and the measure of population structuring of Eurasian Woodcock (Scolopax rusticola) in Hungary in spring. We tested whether any subpopulations can be identified in our sample, and we also examined whether the individuals that occurred closer to each other in space and in timewere alsomore similar in genetic terms. We analysed samples from 240 free-ranging birds collected during legal hunting from mid-February to the end of April in 2015 from different parts of the country. The Bayesian clustering method andMarkov ChainMonte Carlo simulation were used to infer the most probable number of genetic clusters without a priori definition of populations. The second approach was a discriminant analysis of principal components in order to identify clusters of individuals without population geneticmodels.Additionally,we fitted a general linear model with the genetic distance between samples as the dependent variable, the temporal (days) and the geographical (meters) distances and the interactions of these factors as independent variables.We found high genetic diversity and lowlevel of population structuring in our samples.Moreover, our results did not support the assumptions thatWoodcocks occurring in different places or at different times in Hungary would also belong to different breeding populations. [ABSTRACT FROM AUTHOR]

Wild meat often retains metallic particles originating from the ammunition fired by hunters. Since ammunition are traditionally lead (Pb)-based, the consumption of game meat may entail the ingestion of Pb embedded in tissues. To assess the related risks to human health, information is needed on the number, dimension and spatial distribution of Pb particles embedded in popular quarry species. In this study, we focused on the Eurasian woodcock (Scolopax rusticola), a medium-sized bird intensively hunted across its range. We X-rayed 59 carcasses of woodcock shot by Italian hunters in Ukraine. To check the ammunition types and evaluate the mean weight of the embedded gunshot, we excised a sample of 62 whole pellets from 20 birds. Ammunition residues were found in 57 of the 59 woodcock (96.6%). Radiographs revealed 215 whole pellets and 125 fragmentation centres in 51 (mean=3.64) and in 48 birds (mean=2.14), respectively. Most fragmentation centres (75.7%) contained tiny particles (<1 mm). The overall estimated Pb load ranged from 45 to 52 mg/100 g wet weight, most of which (84.6%) in edible parts. The number of embedded pellets per unit of body mass (1.21/100 g of body weight) was higher in comparison with other bird species and also with woodcock shot in the UK, presumably owing to the hunting methods adopted by Italian hunters. The quantity and characteristics of ammunition residues we found suggest that game meat consumers are exposed to a relevant Pb assumption. [ABSTRACT FROM AUTHOR]

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The article discusses a study on nesting of American woodcocks in Clay County, Florida, during the 2014 nesting season.

ABSTRACT The American woodcock ( Scolopax minor) population has declined since the late 1960s across its range and is now considered a species of special concern. Research on woodcock habitat use during migration and migratory routes through the Central Flyway has been limited. We assessed woodcock phenology, estimated density, and nocturnal habitat use in fields on public lands in the lower Mississippi Alluvial Valley portion of Arkansas during November and December of 2010 and 2011. We used all-terrain vehicles to survey woodcock along transects in 67 fields of 8 field types. We analyzed data using hierarchical distance sampling. We detected woodcock from the first week in November through the third week in December but in low numbers. We did not detect woodcock in millet or rice fields, whereas woodcock had the highest estimated densities in unharvested soybeans. All other crop type-post-harvest management combinations had low woodcock densities. We did not detect woodcock in fields <8 ha or >40 ha. Woodcock in the lower Mississippi Alluvial Valley may benefit from management for unharvested soybean fields of moderate size (approx. 8-40 ha). © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Wildlife must acquire resources while avoiding predation, and sometimes this requires commuting between sites. During summer, American woodcock often fly between forests and fields where they spend the day and night, respectively. The advantage of this behavior is poorly known. We found that preferred foods of woodcock were more abundant in forests, and woodcock predators were less active in fields. Thus, commuting by woodcock during summer allows them to feed during the day and avoid predators at night.Moving between sites is a common behavior employed by prey in order to balance trade-offs associated with acquiring resources and avoiding predators. At dusk during summer, American woodcock frequently fly from diurnal coverts in forests to nocturnal roost fields. We tested 2 hypotheses, the foraging-benefit hypothesis and predation-risk hypothesis, to determine the benefit gained by woodcock that commute. We used telemetry to identify the diurnal coverts and nocturnal roost fields used by woodcock in Rhode Island, USA, during 2 summers. At each site, we measured the availability and diversity of woodcock prey, soil properties, and mammalian predator activity. Earthworms were 3–4 times more abundant at diurnal coverts than nocturnal roost fields. The richness and diversity of woodcock foods was greater at diurnal coverts during 2011 but similar between sites during 2012. Soil moisture content was about 1.5 times greater at diurnal coverts, whereas other soil properties were similar between sites. At night, mammalian predators visited diurnal coverts more frequently than nocturnal roost fields for 73% of the woodcock we monitored during 2011. During 2012, the number of days until initial predator visit was 1.8 times greater at nocturnal roost fields. Our results provide the first empirical support for the predation-risk hypothesis. During summer, woodcock fly from diurnal coverts to nocturnal roost fields to avoid predators and not to feed. [ABSTRACT FROM PUBLISHER]

This research examines the relationship of abiotic factors to the autumn number increase of Eurasian woodcocks in a wintering area. Data on the number of woodcocks spotted per day using dogs for 12 years in an area of Macedonia are presented. From these records, we attempt to correlate the increase in number of woodcocks with moon phase, photoperiod, temperature, precipitation, visibility, wind intensity and barometric pressure. Meteorological data were obtained from five meteorological stations located in the study area, breeding areas and along the migration route. Descriptive and applied statistics [Factor Analysis, analysis of variance (ANOVA) and Binary Logistic Regression] were used for the analysis. Woodcock numbers increase significantly in October and November. Barometric pressure, wind and precipitation, as measured by the nearer climatic stations to the study area, influence the increase in number of woodcocks. The between-years analysis showed that woodcocks’ arrival was delayed in warmer autumns. Correlating the numerical increase of woodcocks with abiotic factors is a complicated phenomenon, but the constructed model provides evidence for some patterns and it facilitates the design of a future study. [ABSTRACT FROM PUBLISHER]

We estimated fall (10 Sep-8 Nov) survival rates, cause-specific mortality rates, and determined the magnitude and sources of mortality of 1,035 radio-marked American woodcock ( Scolopax minor) in Michigan, Minnesota, and Wisconsin during 2001-2004. In all 3 states, we radio-marked woodcock on paired study areas; 1 of which was open to hunting and expected to receive moderate to high hunter use and the other of which was either closed to hunting (Michigan and Minnesota) or was relatively inaccessible to hunters (Wisconsin). We used Program MARK to estimate fall survival rates, to evaluate a set of candidate models to examine the effects of hunting and several covariates (sex, age, year, state) on survival, and to examine the relationship between survival rates and kill rates due to hunting. Hunting accounted for 70% of the 86 woodcock deaths in the hunted areas, followed by predation (20%) and various other sources of mortality (10%). Woodcock deaths that occurred in the non-hunted and lightly hunted areas ( n = 50) were caused by predators (46%), hunting (32%), and various other sources (22%). Based on small-sample corrected Akaike's Information Criterion values, variation in fall survival of woodcock was best explained by treatment (i.e., hunted vs. non-hunted), year, and period (pre-hunting season intervals vs. hunting season intervals). The average fall survival estimate from our best model for woodcock in the non-hunted areas (0.893, 95% CI = 0.864-0.923) was greater than the average for the hunted areas (0.820, 95% CI = 0.786-0.854 [this estimate includes data from the lightly hunted area in Wisconsin]), and the average treatment effect (i.e., greater survival rates in non-hunted areas) was 0.074 (95% CI = 0.018-0.129). The kill rate due to hunting was 0.120 (95% CI = 0.090-0.151) when data were pooled among states and years. We detected a negative relationship between hunting kill rates and survival in our hunted areas, which suggests that hunting mortality was at least partially additive during fall. Our results illustrate the influence of hunting relative to other sources of mortality in Michigan, Minnesota, and Wisconsin, and indicate that managers may be able to influence fall survival rates by manipulating hunting regulations or access on public land. © 2013 The Wildlife Society. [ABSTRACT FROM AUTHOR]

We evaluated sites on an industrial forest in central Arkansas that American Woodcocks (Scolopax minor) used for courtship during their spring migration. Our main objective was to determine the vegetation characteristics used by male woodcocks on their courtship sites within early successional pine stands. We quantified use within three stages of early successional pine stand; pine seedling (1 year old), young-pine sapling (2-3 years old), and old-pine sapling (4-5 years old). We used crespuscular surveys as an index to the number of woodcock using each stand. We completed surveys in January-March 2010 and 2011 on eight stands of each stage (n 5 24) during 7-10 day sampling periods across spring migration. We quantified the vegetation structure of each stand including the percent of bare ground, standing herbaceous, flattened herbaceous, shrub, coarse woody debris, and canopy cover and horizontal density. We found that woodcocks used stands with greater shrub, standing herbaceous, and flattened herbaceous cover. This is different from other studies in the southern United States that have shown woodcocks to use areas with sparse vegetation and increased bare ground. We suggest this disparity occurred because previous studies assumed constant detection between stands with different vegetative structure, whereas we completed detection tests to determine how vegetative structure may influence detection between stand types and incorporated these differences in detection into our analyses. [ABSTRACT FROM AUTHOR]

The Eurasian woodcock Scolopax rusticola is a valued game species in southwestern Europe, which is locally under a high hunting pressure. Disturbance due to hunting can lead to avoidance of wintering areas or have an impact on population dynamics owing to behavioural changes. We studied the impact of disturbance on 54 radio-tagged woodcocks under an experimental framework. The birds were allocated to the following three groups: simulated hunting disturbance (controlled disturbance; CD), hunted (H) and control (C). We studied the following four behavioural elements: space use, activity duration, number of commuting flights and date of spring migration departure. We found no differences in behavioural responses between the groups except for space use. A majority of CD birds used larger ranges during daytime than did H and C birds but did not change their nocturnal sites. To a large extent, this nocturnal site fidelity likely accounted for the weak disturbance effect, in so far as food intake was ensured. Our study underlines the importance of permanent meadows in the surroundings of forests to help this species to better withstand hunting disturbance. [ABSTRACT FROM AUTHOR]

Since the late 1960s, American woodcock ( Scolopax minor) have undergone population declines because of habitat loss. Previous research suggested ridge and furrow topography in conventionally tilled soybean fields provided critical nocturnal cover as birds foraged on earthworms. However, the use of no-till technology has increased and many fields now lack ridge and furrow topography. We assessed woodcock winter nocturnal foraging habitat use given recent changes in agricultural technology, and investigated how field treatment, earthworm abundance, and environmental variables affect the selection of nocturnal foraging sites. We counted woodcock along transects in 5 field treatments twice in each of 67 fields during December-March 2008-2009 and 72 fields during December-March 2009-2010. During both seasons, we collected earthworm and soil samples from a subset of fields of each field treatment. Woodcock densities were at least twice as high in no-till soybean fields planted after corn and in undisked corn fields with mowed stalks than in other field treatments. No-till soybean planted after corn and undisked corn fields contained ridge and furrow topography, whereas other crops did not, and earthworms were at least 1.5 times more abundant in no-till soybean fields than other field treatments. Ridges and furrows in no-till soybean fields planted after corn and undisked corn fields may provide wintering woodcock with thermal protection and concealment from predators. No-till soybean fields planted after corn offered the additional benefit of relatively high food availability. The presence of ridge and furrow topography can be used to predict woodcock field use on the wintering grounds in agricultural areas. Farmers can provide nocturnal winter foraging sites for woodcock by delaying field disking and leaving ridge and furrow topography in crop fields. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Both evolutionary ecologists and wildlife managers make inference based on how fitness and demography vary in space. Spatial variation in survival can be difficult to assess in the wild because (1) multisite study designs are not well suited to populations that are continuously distributed across a large area and (2) available statistical models accounting for detectability less than 1.0 do not easily cope with geographical coordinates. Here we use penalized splines within a Bayesian state-space modeling framework to estimate and visualize survival probability in two dimensions. The approach is flexible in that no parametric form for the relationship between survival and coordinates need be specified a priori. To illustrate our method, we study a game species, the Eurasian Woodcock Scolopax rusticola, based on band recovery data (5000 individuals) collected over a >50 000-km2 area in west-central France with contrasted habitats and hunting pressures. We find that spatial variation in survival probability matches an index of hunting pressure and creates a mosaic of population sources and sinks. Such analyses could provide guidance concerning the spatial management of hunting intensity or could be used to identify pathways of spatial variation in fitness, for example, to study adaptation to changing landscape and climate. [ABSTRACT FROM AUTHOR]

Quality of recently used foraging areas is likely an important predictor of fidelity to specific locations in the future. We monitored movement and habitat use of 58 adult female American woodcock Scolopax minor at three study areas in Minnesota, Wisconsin and Michigan, USA, during autumn 2002 and 2003, to assess the relationship between foraging habitat use decisions and environmental conditions at previously used foraging locations. We assessed whether habitat variables which related to food and weather were related to distance between locations on subsequent days of individual woodcock that choose diurnal foraging locations when they return from night-time roosting locations. We predicted that woodcock would return to foraging locations used on the previous day (i.e. shorter distances between daily foraging locations) when environmental conditions on the prior day were favourable. Woodcock generally made short (i.e. 48% <50 m and 91% <400 m) between-day movements, but also occasionally (∼7%) abandoned prior foraging areas. The primary determinants of woodcock movements during autumn (prior to migration) were low local food availability and potential for increased food availability elsewhere. The quality of foraging locations was an important predictor of future foraging habitat use for woodcock, consistent with the hypothesis that woodcock movement behaviour balances the risks associated with movement with the potential benefits of increased energy intake in new foraging areas. [ABSTRACT FROM AUTHOR]

American Woodcock singing-ground surveys (SGS) have been conducted annually on Fort Drum Military Installation since 1992 (excluding 1993 and 2000). These SGS indicate Fort Drum has a stable to slightly increasing breeding woodcock population, with average numbers of males heard per route ranging between 13.00 and 22.58 birds. These numbers are significantly higher, and in stark contrast, to many parts of the American Woodcock's range, where numbers have been in decline for over 30 years. We suggest that current forest management practices and military training create favorable successional regimes that satisfy all necessary life-history requirements and help sustain these densities of breeding woodcock at Fort Drum. [ABSTRACT FROM AUTHOR]

Investigation of bird migration has often highlighted the importance of external factors in determining timing of migration. However, little distinction has been made between short- and long-distance migrants and between local and flight birds (passage migrants) in describing migration chronology. In addition, measures of food abundance as a proximate factor influencing timing of migration are lacking in studies of migration chronology. To address the relationship between environmental variables and timing of migration, we quantified the relative importance of proximate external factors on migration chronology of local American woodcock (Scolopax minor), a short distance migrant, using event-time analysis methods (survival analysis). We captured 1,094 woodcock local to our study sites in Michigan, Minnesota, and Wisconsin (USA) during autumn 2002--2004 and documented 786 departure dates for these birds. Photoperiod appeared to provide an initial proximate cue for timing of departure. Moon phase was important in modifying timing of departure, which may serve as a navigational aid in piloting and possibly orientation. Local synoptic weather variables also contributed to timing of departure by changing the rate of departure from our study sites. We found no evidence that food availability influenced timing of woodcock departure. Our results suggest that woodcock use a conservative photoperiod-controlled strategy with proximate modifiers for timing of migration rather than relying on abundance of their primary food, earthworms. Managing harvest pressure on local birds by adjusting season lengths may be an effective management tool with consistent migration patterns from year to year based on photoperiod. [ABSTRACT FROM AUTHOR]

The Singing-Ground Survey (SGS) is a primary source of information on population change for American woodcock (Scolopax minor). We analyzed the SGS using a hierarchical log-linear model and compared the estimates of change and annual indices of abundance to a route regression analysis of SGS data. We also grouped SGS routes into Bird Conservation Regions (BCRs) and estimated population change and annual indices using BCRs within states and provinces as strata. Based on the hierarchical model-based estimates, we concluded that woodcock populations were declining in North America between 1968 and 2006 (trend = -0.9%/yr, 95% credible interval: -1.2, -0.5). Singing-Ground Survey results are generally similar between analytical approaches, but the hierarchical model has several important advantages over the route regression. Hierarchical models better accommodate changes in survey efficiency over time and space by treating strata, years, and observers as random effects in the context of a log-linear model, providing trend estimates that are derived directly from the annual indices. We also conducted a hierarchical model analysis of woodcock data from the Christmas Bird Count and the North American Breeding Bird Survey. All surveys showed general consistency in patterns of population change, but the SGS had the shortest credible intervals. We suggest that population management and conservation planning for woodcock involving interpretation of the SGS use estimates provided by the hierarchical model. [ABSTRACT FROM AUTHOR]

Little is known about the migration ecology of the American woodcock (Scolopax minor). From 2001 to 2003, we began a 3-year study to document woodcock fall migration routes, rates, and habitat use from Minnesota, Wisconsin, and Michigan, USA. Some 586 radiomarked woodcock initiated migration. During 224 hours of aerial telemetry, we located 42 radiomarked woodcock in 6 states. Using locations of radiomarked birds, we speculated woodcock migration routes in the central United States. Stopover duration often exceeded 4 days, with some birds stopping longer than a week. Radiomarked birds were located in upland habitats more frequently than bottomland habitats, and used a higher proportion of mature forest than expected. A Geographic Information System was used to map potential woodcock habitat in the Central Region. Based on our results, we identified possible fall migration routes and priority areas for woodcock management in the Central Region. Our results should be used by land managers to prioritize future land acquisition and management of woodcock habitat. [ABSTRACT FROM AUTHOR]

Migratory birds wintering at the same location are usually coming from populations of different origins, in variable proportions. Using data from individuals banded on their wintering grounds and recovered on their breeding areas, we show that such proportions are estimable given that 1) all breeding populations are identified, and 2) the wintering population can be stratified into ≥1 more site than the number of breeding populations. We applied this technique to woodcock (Scolopax rusticola) banded while wintering in France (N = 35,000) and recovered in other European countries (N=520). We estimated that the proportion of eastern woodcock among those wintering in France varied spatially, ranging from 70% in northwest France to nearly 100% in southeast France, and increased substantially over the last 15 years. Overall, the method appears powerful to quantify spatial variation of the composition of a population receiving individuals from various origins. [ABSTRACT FROM AUTHOR]

We used an over-dispersed Poisson regression with fixed and random effects, fitted by Markov chain Monte Carlo methods, to model population spatial patterns of relative abundance of American woodcock (Scolopax minor) across its breeding range in the United States. We predicted North American woodcock Singing Ground Survey counts with a log-linear function of explanatory variables describing habitat, year effects, and observer effects. The model also included a conditional autoregressive term representing potential correlation between adjacent route counts. Categories of explanatory habitat variables in the model included land-cover composition, climate, terrain heterogeneity, and human influence. Woodcock counts were higher in landscapes with more forest, especially aspen (Populus tremuloides) and birch (Betula spp.) forest, and in locations with a high degree of interspersion among forest, shrubs, and grasslands. Woodcock counts were lower in landscapes with a high degree of human development. The most noteworthy practical application of this spatial modeling approach was the ability to map predicted relative abundance. Based on a map of predicted relative abundance derived from the posterior parameter estimates, we identified major concentrations of woodcock abundance in east-central Minnesota, USA, the intersection of Vermont, USA, New York, USA, and Ontario, Canada, the upper peninsula of Michigan, USA, and St. Lawrence County, New York. The functional relations we elucidated for the American woodcock provide a basis for the development of management programs and the model and map may serve to focus management and monitoring on areas and habitat features important to American woodcock. [ABSTRACT FROM AUTHOR]

Band-recovery and wing-collection survey data have the potential to provide information on American woodcock (Scolopax minor) fall migration ecology in the Central Region of the United States, yet researchers have not recently analyzed these extensive data sets. We analyzed all direct recoveries of woodcock banded in Michigan, Minnesota, and Wisconsin, USA, as well as wing-collection survey data, to determine the progression of fall migration, the migration direction, and the final destination of woodcock migrating from these states. We did not observe migration initiation based on band recoveries until late October and early November, with most migration occurring during November. Wing-receipt data showed a similar trend, with most change in mean receipt latitude occurring from 1 November to 5 December. During November, wing receipts were spread through the entire Central Region. By 15-31 December, 92% (n = 26) of band recoveries were on the wintering grounds (south of latitude 338N). Most banded woodcock from Michigan, Minnesota, and Wisconsin wintered in Louisiana, USA. Woodcock banded in these states will be exposed to harvest for most of the hunting season because they remain in these states through November. If the population status of local birds is a concern, managers should consider this migration pattern when setting season dates. [ABSTRACT FROM AUTHOR]

To determine if significant differences exist in lead (Pb) accumulation in different bones, especially those most often used for bone-Pb studies in wildlife, we compared Pb concentrations in radius, ulna, humerus, femur, and tibia of Common Eider (Somateria mollissima); and radius/ulna (combined), femur, and tibia of American Woodcock (Scolopax minor). There were no significant differences in bone-Pb concentrations among woodcock bones over a wide range of Pb concentrations (3–311μg/g). In eider, where bone-Pb concentrations were low (<10μg/g), leg bones had significantly higher Pb concentrations (approximately 30–40%) than wing bones from the same individuals. The variation among individual birds was greater than the variation among different bones within a bird. Based on our findings, we conclude that one type of bone may be substituted for another in bone-Pb studies although the same bone type should be analyzed for all birds within a study, whenever possible. [Copyright &y& Elsevier]

The article describes an original yet simple method to sample earthworms, designed for wildlife biologists studying nocturnal vertebrate predators. It tests the new sampling procedure as part of an ecological study on the Eurasian woodcock, a bird that mainly forages on earthworms. A correlation between habitat selection and earthworm availability, in summer and winter is found in studies on habitat selection in woodcocks. It investigates the earthworm biomass really available within the top 10 centimeter of fields at night, with a new simple sampling procedure.

Scolopax minor (American Woodcock) populations have been declining for the past several decades. Weather conditions have been hypothesized to affect reproductive efforts in February and March in the southern United States, but similar influences on January breeding activities are unknown. We used a 17-year harvest data set from eastern Texas to examine the influence of several temperature and precipitation measures, female body mass, and forest habitat type on the occurrence of reproduction by Woodcock in January. Only adult females exhibited characteristics of breeding activity. There was annual variation (0-29%) in the occurrence of breeding adult females, but local temperature and precipitation measures were not correlated with January reproduction. More breeding Woodcock were harvested in open sapling stands than other habitats. Environmental factors other than monthly temperature and precipitation may influence January reproductive efforts of Woodcock in eastern Texas. We suggest investigation of timing of fall migration and condition of the birds upon arrival on wintering grounds as potential factors influencing reproductive efforts in January. [ABSTRACT FROM AUTHOR]

Numbers of American woodcock (Scolopax minor) males counted on the annual singing ground survey (SGS) have declined over the last 35 years at an average rate of 2.3% per year in the Eastern Region and 1.8% per year in the Central Region. Although hunting was not thought to be a cause of these declines, mortality caused by hunters can be controlled. Furthermore, there has been no research on effects of hunting mortality on woodcock populations at local and regional levels on the breeding grounds. We used radiotelemetry to determine survival rates and causes of mortality for 913 woodcock captured during fall 1997-2000 on 7 areas in Maine, New Hampshire, Pennsylvania, and Vermont, USA. Three of 7 sites were closed to hunting. For all sites and all years combined, 176 woodcock died, and 130 were censored, of which 39 were censored mortalities. Predation was the major (n = 134, 76%) cause of mortality. Mammals accounted for 56% of the predation, raptors accounted for 25%, and 19% was attributed to unknown predators. On hunted sites, 36% of the total mortality (n = 102) was caused by hunting, 63% by predation, and 1 bird starved. Kaplan-Meier survival curves did not differ between hunted and nonhunted sites among years (P = 0.46). Overall, point estimates of survival did not differ (P = 0.217) between hunted (SR = 0.636, SE = 0.04) and nonhunted sites (SR = 0.661, SE = 0.08). We modeled hazard rates from hunting and natural mortality events using program MARK. Akaike's Information Criterion supported using a model with common constant hazards from both hunting and natural causes for groups of sites. Groupings of sites for hazard rates from natural causes were not influenced by whether a site was hunted or not. Models detected no effects of woodcock age and sex (P= 0.52) on survival. Proportional hazards models comparing hunted and nonhunted sites found no effects of age and sex (P= 0.45), interactions of age, sex, capture weight, and bill length (P≥ 0.269). Our data suggest that current hunting regulations are not causing lower survival of woodcock. [ABSTRACT FROM AUTHOR]

Information on population connectivity throughout the annual cycle has become more crucial, because populations of many migratory birds are in decline. One such species is the American Woodcock (Scolopax minor), which inhabits early-successional forests in eastern North America. Although band recoveries have proved useful for dividing populations of this game bird species into an Eastern Region and Central Region for management purposes, these data do not provide enough detail to determine the breeding population of origin of birds recovered on stopover and wintering areas. To obtain more fine-scale data, we undertook a phylogeographic study of American Woodcock populations throughout their primary breeding range in the eastern United States and Canada using mitochondrial DNA (mtDNA) sequences from the hypervariable control region I (CRI) and ND6 gene. Despite high haplotype diversity, nucleotide diversity was low and there was no phylogeographic structure among American Woodcock populations across the species range, with birds from many states and provinces in both management regions sharing identical haplotypes. Results suggest recent or ongoing gene flow among populations, with asymmetric movement of birds between migration flyways. As has been demonstrated for several other avian species in North America, American Woodcock appear to have undergone a rapid population expansion billowing the late Pleistocene glacial retreat. Thus, a combination of historical demographic factors and recent or ongoing gene flow mask any population structure based on mtDNA that might accrue from philopatry to breeding areas observed in studies of marked birds. [ABSTRACT FROM AUTHOR]

Deals with a study which estimated the survival and recovery rates of American woodcock banded in Michigan from 1968 through 1998. Background to the study; Methods; Results and discussion; Implications for wildlife management.

Presents a study which described the successional habitats of ruffed grouse species Bonasa umbellus and American woodcock Scolopax minor in the eastern United States and recommended appropriate management of their habitat. Importance of shrub-dominated and young forest habitats to ruffed grouse and American woodcock; Distribution and status of the bird species; Cause of population declines.

Presents a study which estimated winter survival and documented the hunting mortality rates of American woodcock in south central Louisiana. Decline in the abundance of American woodcock; Methodology used; Results and discussion.