American Woodcock Symposium

A Bayesian Hierarchical Model for Estimating American Woodcock Harvest

Todd W. Arnold — Mon, 02 Dec 2019 00:00:00 -0600

Estimates of total harvest help inform harvest management decisions, but such data are also useful for estimating population size and composition in demographic models. Historical estimates for U.S. harvest of American woodcock (Scolopax minor; hereafter woodcock) are available from 2 separate surveys: the 1964−2001 duck stamp survey (DSS) that sampled woodcock hunters who also hunted waterfowl, and the 1999−2016 Harvest Information Program (HIP) that sampled all licensed woodcock hunters. During overlap years (1999−2001), HIP estimates of total woodcock harvest were approximately twice as large as DSS estimates, but with only 3 years of overlap there was little potential to develop robust correction factors for historical DSS data. I developed a model of historical woodcock harvest that posited 3 groups of woodcock hunters, including those who always, sometimes, or never hunted waterfowl. During the HIP survey all 3 groups were included in harvest surveys; during the DSS years, however, only woodcock hunters who always hunted waterfowl were reliably sampled during all years, but I used annual duck stamp sales as a covariate to help predict harvest by woodcock hunters who hunted waterfowl irregularly. Using a reverse-time (2016 to 1964) model that assumed these 3 proportions of harvest remained constant through time, I was able to estimate total harvest in all years by estimating the latent component of harvest by non-waterfowl hunters. Averaged over all harvest jurisdictions, this model estimated that hunters who always, sometimes, or never hunted waterfowl contributed 43%, 32%, and 25% of the total woodcock harvest. Using these relationships, I estimated total harvest during all years (1964−2016) using data from both harvest surveys, although estimates based only on DSS data had greater uncertainty. In combination with band recovery data and harvest composition from the Parts Collection Survey, analysts could use estimates of historical harvest to estimate population size, composition, fecundity, and survival dating back to the initiation of harvest surveys in 1964.

Evaluating Techniques for Estimating Post-Breeding-Season Age Ratios for American Woodcock

Kyle O. Daly, David E. Andersen, Wayne L. Brininger, Thomas R. Cooper — Mon, 02 Dec 2019 00:00:00 -0600

Estimating American woodcock (Scolopax minor; hereafter, woodcock) vital rates at a landscape scale requires considerable effort and expense, but provides a means of assessing population response to management. Age ratios derived from capturing woodcock (e.g., age ratios derived from mist-netting or night-lighting) during late summer may be useful proxies of local production, and require much less effort and expense to obtain than estimating local production directly. To assess whether such age ratios were similar to estimates of production derived from estimating vital rates, we estimated post-breeding-season age ratios (juveniles/adult female) at a habitat-management demonstration area in west-central Minnesota using radio telemetry and nest monitoring, and by capturing woodcock using mist nets and night-lighting. In 2011 and 2012 we radio-marked and tracked 41 adult female and 73 juvenile woodcock and monitored 51 broods and 48 nests; we used the collected data to inform population models and derive post-breeding-season age ratios. In July of 2011 and 2012, we captured 204 woodcock using mist nets by exploiting crepuscular movements from diurnal feeding cover to roosting fields and 69 woodcock via night-lighting on nocturnal roosting fields. Estimates of age ratios derived from our population model were 1.07 (95% CI: 0.27 – 2.45) in 2011 and 2.59 (95% CI: 1.04 – 4.95) in 2012. We attribute the higher point estimate of age ratio in 2012 to higher nest and juvenile survival rates during that year. Age ratios from mist-netting were 3.82 (95% CI: 1.99 – 7.13) in 2011 and 2.37 (95% CI: 1.43 – 3.73) in 2012 and from night-lighting were 1.62 (95% CI: 0.69 – 3.28) in 2011 and 0.42 (95% CI: 0.06 – 1.00) in 2012. Age ratio point estimates derived from mist-netting and night-lighting varied considerably between years, with neither method providing a ratio similar to point estimates derived from our population model. The only statistically significant difference (based on 95% CIs) between any of our age ratio estimates was for night-lighting in 2012, with that estimate being lower than the estimates from mist-netting and our population model. Based on these results, age ratios of production of young derived from mist-netting and might-lighting in late summer may not reflect local production, and may be influenced by both local and landscape-scale movements of woodcock following the breeding season. We conclude that without further evaluation of factors that affect post-breeding-season age ratios of local woodcock populations, age ratios derived from mist-netting and night-lighting in summer may not be useful proxies of local recruitment.

Breeding Season Survival of American Woodcock at a Habitat Demonstration Area in Minnesota

Kyle O. Daly, David E. Andersen, Wayne L. Brininger, Thomas R. Cooper — Mon, 02 Dec 2019 00:00:00 -0600

American woodcock (Scolopax minor; hereafter woodcock) best management practices (BMPs) applied at a landscape scale have been proposed to increase woodcock population densities, yet little information exists regarding population vital rates following application of BMPs. We estimated survival rates of woodcock adult females, nests, and juveniles at a woodcock habitat-management demonstration area in west-central Minnesota during the spring and summer (23 March – 30 June) of 2011 and 2012. We radio-marked and tracked 41 adult female and 73 juvenile woodcock, and monitored 51 broods and 48 woodcock nests to determine fates. We used Kaplan-Meier survival analysis to estimate survival rates of females, nests, and juveniles for both 2011 and 2012 and logistic-exposure models to assess relationships between survival and weather covariates, individual life history traits, and vegetation characteristics resulting from BMPs. Breeding season cumulative survival rate for adult females from 1 April – 30 June was 0.695 (95% CI: 0.357 – 1.052) in 2011, 0.740 (95% CI: 0.391 – 1.091) in 2012, and 0.751 (95% CI: 0.499 – 1.000) when pooling data from both years. Nest survival rate for the 24-day laying and incubation period was 0.458 (95% CI: 0.299 – 0.696) in 2011 and 0.786 (95% CI: 0.616 – 0.998) in 2012. Cumulative survival rate for juvenile woodcock for a 61-day period (1 May – 30 June) following hatch through mid-summer, when juveniles are independent from adults, was 0.330 (95% CI: 0.188 – 0.613) in 2011 and 0.576 (95% CI: 0.398 – 0.833) in 2012. In all logistic-exposure survival models, we included a year covariate (females: β2011= −0.16, 95% CI: −1.67 to 1.45, nests: β2011= −0.768, 95% CI: −1.70 to 0.166, juveniles: β2011= −0.85, 95% CI: −1.77 to 0.07) to account for between-year variation in survival rates, although removing that covariate in models did not result in changes in relations between survival rates and other covariates. Our best-supported model of female survival rate was the null model, suggesting female survival rate was constant across years, and our best-supported model of nest survival rate included only a year covariate. Our best-supported model of juvenile survival rate included the covariates year, juvenile age (βAGE = 0.098, 95% CI: 0.04 to 0.16), minimum temperature (βMINT = 0.14, 95% CI: −0.004 to 0.28), and precipitation (βPCPT = −0.20, 95% CI: −0.39 to −0.01). Juvenile survival rate increased with age and decreased with the amount of precipitation and had a weak positive relation with stem density (βSTEM = 0.0001, 95% CI: 0.000 to 0.0003). Woodcock in our study almost solely used areas where BMPs had been applied on the landscape within the last 20 years and that had similar vegetation structure; in those settings, only juvenile survival rate was related to local environmental conditions.

Assessment of the American Woodcock Wing-Collection Survey

Thomas R. Cooper — Tue, 03 Dec 2019 00:00:00 -0600

The American Woodcock Wing-collection Survey (WCS) is a cooperative survey (U.S. Fish and Wildlife Service [FWS], State Wildlife Agencies, and U.S. woodcock hunters) that has been conducted annually since 1963 in the United States. The primary objective of the WCS is to provide an index to the reproductive success of American woodcock (Scolopax minor; hereafter, woodcock) because age and sex of harvested birds can be determined using feather characteristics. Based on recent harvest survey information, U.S. woodcock hunters harvest ≈ 300,000 woodcock per year, whereas hunters participating in the WCS contributed an average of 13,400 wings per year during the 2008–2012 seasons. Based on the sample size and harvest estimate, the WCS currently samples about 4.5% of the harvested woodcock every year, which is a much higher rate than sampled for waterfowl. For example, the Waterfowl Parts Collection Survey sampled ≈ 0.25% of the Mississippi Flyway waterfowl harvest in 2012. My objective was to assess if there were any differences in the proportion of wings by cohort (adult male, adult female, juvenile male, juvenile female) if wing collection was limited to a hunter’s first 5 successful hunts, rather than all of their successful hunts as is currently done. I analyzed WCS data from the 2008–2012 woodcock seasons and used Pearson’s Chi-Square Goodness of Fit test to assess if the proportion of wings for each cohort differed between the full data set and data from a hunter’s first 5 successful hunts. Limiting data collection to the first 5 successful hunts resulted in a 5-year average (2008–2012) of 1,848 fewer envelopes and 4,202 fewer wings being submitted to the survey. Chi-square analysis indicated there was no difference in the proportion of wings by cohort between the full and partial data set. My results indicate that reducing the sample size of woodcock wings would not bias age ratio estimates and would result in considerable cost savings to the WCS. The FWS would realize cost savings through fewer envelopes having to be mailed and less staff time in processing wings when they are received.

Using Infrared Technology to Locate and Monitor American Woodcock Nests

Thomas J. Keller, Samara Trusso, Ian D. Gregg, Lisa Williams — Tue, 03 Dec 2019 00:00:00 -0600

Methods for locating American woodcock (Scolopax minor; hereafter woodcock) whether individuals, nests, or broods, have remained largely unchanged for more than 75 years, but use of current technology has the potential to increase efficiency and decrease observer-caused disturbance. Primary methods of searching for and locating woodcock have included the use of pointing dogs, and telemetry after capture using mist nets, nightlighting, or live traps. We tested the feasibility of using Forward Looking Infrared Radar (FLIR) cameras to locate individual woodcock, nests, and broods in the spring (24 March – 11 May) of 2015 as part of a research project to determine the timing of nest initiation along 3 American Woodcock Singing-Ground Survey (SGS) routes in southwestern Pennsylvania. By using FLIR to search potential woodcock nesting cover adjacent to SGS routes, we located a total of 28 nests and 4 broods, 2 of which were not linked to a previously known nest. We also located 180 individual woodcock. Searching took place over a total of 22 days, not all contiguous, for a total of 58.05 hours. Nest-searching efficiency using FLIR was 0.48 nests/hour compared to published reports of efficiency using historical search methods ranging from 0.03–0.4 nests/hour. The FLIR method is not only more efficient, but provides a non-intrusive approach to locating and monitoring nesting woodcock. In addition to nesting ecology, FLIR may have additional applications in woodcock research, including improving efficiency of capture methods and monitoring nocturnal behavior and habitat use. The technology also proved to be excellent at locating other birds and mammals, and therefore has many possible uses in wildlife research.

Detecting Passage of Migrating Woodcock Using Nano Tag Technology

D. G. McAuley, R. E. Brown — Tue, 03 Dec 2019 00:00:00 -0600

Nano tags are regular VHF radio transmitters that broadcast on a single frequency that is encoded. Signals are picked up by towers and stored. Data can be stored at the tower for several months and then downloaded. After downloading, data are sent to Canada to be sorted and then sent to the individual researchers. Costs of the nano tags are the same as conventional VHF transmitter projects (about $210.00). The cost of the receiver is about $300. Currently there are about 564 receiving towers, mostly along the Atlantic coast, and 30 different projects, although the system can handle more studies. The data can be used to study movement patterns, migration timing, and speed, and also to give survival estimates. Birds do not need to be followed on the ground or from the air. Transmitters range in weight from 0.26 grams to 4.3 grams, and have a life expectancy of 10 to more than 11,000 days. We used the 4.6-gram transmitters with a life expectancy of 405 days.

In 2015 we deployed 24 transmitters at Moosehorn NWR during late September and October. We were interested in timing of migration and stopovers. Ten transmitters were detected in CT at 2 different towers. One bird was picked up by both towers, 2 were detected in RI, 1 at Plum Island on Long Island, NY, 3 at Cape May, NJ, and 2 at the Eastern Shores of VA NWR. Data from 2017 will be presented as well.

Determining Gender of Flushing American Woodcock (Scolopax minor)

E. Frank Bowers — Tue, 03 Dec 2019 00:00:00 -0600

I investigated the possibility of determining gender of flushed American woodcock (Scolopax minor) by using flush and flight behavior occurring in the first 9–11 m of an initial flush. Correct gender predictions of flushing birds could provide an option for hunters to voluntarily modify their harvest. During 2013–2015, I harvested 130 woodcock and found that most females (>75% on initial flush) reached greater heights (>3m) than males in the first 9–11 m of the first flush. Such tower-flush behavior was not common for males, who instead flushed more horizontally than vertically, appeared smaller, and flew in a more twisting manner than females.

In 2017, I verified my gender assignment method and found that I could identify the higher, tower-flushing females >63% of the time before deciding to shoot. Using the tower-flushing behavior method, woodcock hunters have an option to reduce female harvest, possibly resulting in more breeding females returning to breed the following season. Four conditions and situations that could prompt hunters to exercise limited harvest of females include: (1) whenever one or two females have been bagged that day, (2) the hunt area is saturated with woodcock, (3) the hunt site will be hunted numerous times in a season, and (4) hunters wanting to improve their ability to recognize flushed females.

Behavior of Incubating American Woodcock (Scolopax minor) in Maine

Daniel G. McAuley, David A. Clugston, Jerry R. Longcore, William A. Halteman — Tue, 03 Dec 2019 00:00:00 -0600

During April – June 1987 and 1988, we remotely monitored 14 radio-marked female American Woodcock (Scolopax minor; hereafter woodcock) at 18 nest sites on Moosehorn National Wildlife Refuge in Maine, U.S.A., to determine patterns and constancy of nest incubation behavior. On average, females spent 93% of their time on the nest and 7% off the nest, leaving nests for an average of 104.2 minutes during a 24-hour period. Time off the nest each day did not vary by year, daily high temperature, or amount of daily precipitation. Our data suggest that renesting females spent more time off nest/day than females on first nests, and that second-year females made more diurnal recesses from the nest than aftersecond- year females. Most woodcock left the nest during crepuscular periods. Our results provide information about nest incubation constancy, and may be useful for informing woodcock research and habitat management.

Preface

David Krementz, David Andersen, Thomas R. Cooper — Tue, 26 Nov 2019 00:00:00 -0600

Communicating Effectively about Young Forest Management to Benefit Associated Wildlife Species

Phil T. Seng, David J. Case — Mon, 02 Dec 2019 00:00:00 -0600

To conserve declining populations of American woodcock (Scolopax minor; hereafter woodcock) and other young forest-associated species, the Wildlife Management Institute contracted with DJ Case & Associates to assess existing communication efforts and investigate strategies that would help achieve the difficult objective of encouraging private landowners to implement young forest management practices on their lands. Our efforts included a literature review, interviews of 30 natural resources professionals, 7 focus groups with private landowners, and a metadata analysis of National Woodland Owner Survey (NWOS) data. Based on this research, we identified 5 target audiences (private, non-industrial woodland owners, conservation professionals with direct landowner contact, other conservation professionals, residents of forested communities, and hunters, especially woodcock and ruffed grouse [Bonasa umbellus] hunters), with objectives for each. We also identified broad strategies for achieving these objectives with each target audience and developed messages based on what these audiences indicated was important to them. Finally, we recommended 3 big-picture actions for the woodcock conservation community to implement the specific communications strategies: 1) design and develop a comprehensive website that provides the information and resources needed by each of the target audiences, 2) create detailed pilot communications campaigns in selected five-county pilot areas, and 3) develop large-scale partnerships among other organizations and entities interested in young forest management. The Wildlife Management Institute and others in the conservation community have embraced and implemented these communication strategies and messages as part of a larger woodcock conservation effort in the Northeast and Upper Midwest USA. Partners have employed many of these messages and strategies in an even broader effort to promote and encourage young forest management throughout the country.

How to Evaluate Woodcock Habitat Management: are Landowners the Answer?

Anna C. Buckardt, Amber M. Roth, Jessica E. Leahy — Mon, 02 Dec 2019 00:00:00 -0600

Loss of young forest, also termed early successional forest, in North America is negatively impacting wildlife populations that rely on this regenerating forest type, especially birds. The Wisconsin Young Forest Partnership (WYFP) targets young forest management efforts to benefit American woodcock (Scolopax minor; hereafter, woodcock) on private lands in Wisconsin. The WYFP uses an adaptive strategy to iteratively evaluate and adjust their habitat management activities. Citizen science can be a valuable evaluation tool in this process. The WYFP aims to develop a citizen science program whereby landowners monitor woodcock in management areas on their properties. We explored the woodcock monitoring preferences and abilities of landowners through questionnaires, interviews, and pilot woodcock surveying to inform the development of a citizen science woodcock monitoring program. Landowners were enthusiastic about participating in woodcock monitoring. When creating a citizen science program for monitoring woodcock it is important to use English units for estimating distance, evaluate landowners’ physical ability to hear peenting woodcock, provide in-person monitoring training, and have flexible data submittal options. Development of a successful citizen science program for monitoring woodcock requires balancing researcher goals with participant preferences and abilities.

Mobilizing Private Landowners to Create American Woodcock Habitat

Bill Buffum, Brian C. Tefft, Roger J. Masse, Scott R. McWilliams — Mon, 02 Dec 2019 00:00:00 -0600

Engaging private landowners in the conservation of American woodcock (Scolopax minor; hereafter, woodcock) in the northeastern United States is important because most forests in the region are privately owned. For this reason, a consortium of conservation agencies in the region has been encouraging private landowners to create young forest vegetation types. This study summarizes the achievements and lessons learned through 3 components of a collaborative outreach program as practiced in Rhode Island, USA since 2008: 1) providing technical and financial assistance to private landowners to support woodcock habitat creation, 2) developing a woodcock management demonstration area in the Great Swamp Wildlife Management Area to support research and landowner trainings, and 3) conducting research on landowner involvement in the creation of young forest. We found that the financial and technical assistance was an important factor motivating private landowners to create young forest. Furthermore, response to a follow-up questionnaire after our trainings was encouraging; 83% of the participants followed up with forest management on their own properties, and creation of young forest was the most common activity. The woodcock demonstration area strongly supported the training programs by allowing landowners to see regenerating clearcuts of 4 different ages in close proximity, and it was used as a research site to determine how woodcock selected certain-aged young forest patches. Our spatial analysis confirmed that the extent of young forest created in Rhode Island during the 7 years after 2004 was almost double the extent created during the previous 7 years, and that private landowners created more habitat than either government agencies or nongovernment organizations. We conclude that private landowners can play an important role in the conservation of woodcock, and recommend an expanded outreach program to mobilize them.

Woodcock is Not a Dirty Word! Using Interest in Wildlife to Engage Private Forest Landowners

Jeremy Holtz — Mon, 02 Dec 2019 00:00:00 -0600

Over the last half century, Wisconsin’s young (or early successional) forest cover has decreased in extent and declined in quality as habitat for associated wildlife. Consequently, many wildlife species have seen population declines. A majority of Wisconsin’s forests are privately owned, and the majority of forest owners report having no management plan. The Wisconsin Young Forest Partnership (WYFP) is a group of agencies, organizations, and businesses that have come together to enhance young forests across ownerships. Together we have developed a program that uses concern for and interest in wildlife species to begin a dialogue with landowners who currently are not actively managing their forests. Over the past 5 years, we have learned what does—and does not—work when trying to begin a dialogue with forest landowners in north-central Wisconsin. The goal of the WYFP is to increase the managed area of aspen (Populus spp.), alder (Alnus spp.), and associated young forest cover to reflect the habitat conditions that American woodcock (Scolopax minor), ruffed grouse (Bonasa umbellus), golden-winged warblers (Vermivora chrysoptera), and other species associated with early successional forest experienced in the 1970s and 1980s. We connect landowners to resources such as natural resource professionals, trained consulting foresters, and, in many cases, habitat funds to pay for plan writing and habitat management. The end result is landowners who are excited about forest management, are actively engaged in forestry practices to improve wildlife habitat, and who have a written plan to help them continue management on their property into the future.

Full paper citation: Jeremy Holtz “Woodcock is Not a Dirty Word! Using Interest in Wildlife to Engage Private Forest Landowners,” The Wildlife Professional, 12(1), 32–35 (February 2018).

Factors Influencing American Woodcock Hunter Satisfaction in Canada

Mon, 02 Dec 2019 00:00:00 -0600

From 1991 to 2005, we surveyed American woodcock (Scolopax minor; hereafter, woodcock) hunters in 3 Canadian provinces to assess hunter satisfaction. Across all submitted reports, 42.0% of the respondents reported a ‘poor’ experience, 35.2% of the hunters reported an ‘average’ experience, and 22.1% of the hunters reported a ‘good’ experience. We analyzed hunter satisfaction rate with an ordered logistic regression that included province, Singing Ground Survey Population Index (SGS index), number of woodcock harvested, hunting effort (hours hunted), environmental conditions before and during the nesting and brood-rearing periods (i.e., prior to the hunting season), precipitation during the post-fledging period, and year as explanatory variables. We also included a random effect for each individual hunter, to account for repeated answers, and for year, to account for short-term irregular perturbations in hunter satisfaction. Hunters from Nova Scotia were on average more satisfied than hunters from Ontario. Hunter satisfaction was positively correlated with the SGS index and the number of woodcock harvested by the hunter during a hunting trip. Hunter satisfaction was negatively correlated with the amount of precipitation during the nesting period and positively correlated with the amount of precipitation during the post-fledging period. However, there was considerable variation in individual hunter response, with 27.7% of the hunters more satisfied than average and 22.8% less satisfied than average. In fact, the individual hunter response accounted for approximately 75.0% of the variability observed in the model, indicating that accounting for hunter satisfaction would require further investigation. In the meantime, promoting woodcock habitat conservation in southern Canada could increase woodcock populations, harvest opportunity, and, by extension, hunter satisfaction.

Promoting Wildlife Habitat and Conservation Partnerships Through State-Funded Grant Programs

Clay B. Buchanan — Mon, 02 Dec 2019 00:00:00 -0600

As hunter numbers decline nationally, state wildlife agencies look for new conservation funding avenues. With the assistance of conservation groups and engaged citizens, the Michigan Department of Natural Resources (MI DNR) was able to secure the passage of a restructured license package, which took effect in 2014. Included in the restructuring was a simplification of the available hunting licenses and a promise to give more back to state citizens for the resulting fee increases. Following up on this promise, the MI DNR Director directed the Wildlife Division to develop and initiate a grant program that would increase wildlife habitat through grant funds given to conservation partners. The Wildlife Habitat Grant Program awarded funds to the first round of successful applicants in spring of 2014, and this competitive grant program is now in its fourth cycle, with projects completed from Iron County in the western Upper Peninsula to Lenawee County in the southeastern Lower Peninsula. The Wildlife Habitat Grant Program has awarded >$4.6 million and has improved or restored wildlife habitat on approximately 3,235 hectares (8,000 acres). As young forests are of high priority, a number of these projects have been focused on American woodcock (Scolopax minor) and ruffed grouse (Bonasa umbellus) habitat, and are often associated with Grouse Enhanced Management Sites (GEMS). Project collaborators have included the Ruffed Grouse Society and American Woodcock Society, U.S. Forest Service, Beaver Island Wildlife Club, National Wild Turkey Federation, Wildlife Management Institute, Soil and Water Conservation Districts, Michigan United Conservation Clubs (MUCC), and private landowners.

Assessment of the American Woodcock Singing-Ground Survey Zone Timing and Coverage

Tue, 03 Dec 2019 00:00:00 -0600

The American woodcock (Scolopax minor; hereafter, woodcock) Singing-Ground Survey (SGS) was developed to inform management decisions by monitoring changes in the relative abundance of woodcock. The timing of the designated survey windows was designed to count resident woodcock while minimizing counting of migrating woodcock. Since the implementation of the SGS in 1968, concerns over survey protocols that may bias data have been raised and investigated; however, the extent of survey coverage and the timing of the survey window zones have not been critically investigated. We used 3 years of data collected from male and female woodcock marked with satellite tags to assess the extent of survey coverage and the timing of the SGS survey windows relative to presence of woodcock. SGS coverage encompassed the majority of woodcock breeding-period sites (locations where marked woodcock returned to in spring) within the U.S. (n = 17, 92%) and approximately half of the breeding-period sites in Canada (n = 6, 43%). Thirteen of the 37 monitored woodcock with known breeding-period site arrival dates (35%) were migrating through a survey zone during an active survey window, all in the northernmost 4 of 5 SGS zones. Thirteen woodcock arrived at breeding-period sites after the start of surveys, and all but one of these was located in the northernmost 2 zones. The combination of migration through a SGS zone during the survey window and arrival at breeding-period sites after the beginning of the survey window in northern zones may result in the SGS weighing too heavily the contribution of routes in the southern portion of the primary breeding range, while weighing too lightly the routes in the northern portion of the primary breeding range. We suggest that additional information is necessary to evaluate whether current survey windows are sufficient, or whether they need to be changed.

Estimating Density and Effective Area Surveyed for American Woodcock

Stefanie M. Bergh, David E. Andersen — Tue, 03 Dec 2019 00:00:00 -0600

The American Woodcock (Scolopax minor; hereafter, woodcock) Singing-ground Survey (SGS) is conducted annually during the woodcock breeding season, and survey points along survey routes are set 0.4 mile (0.65 km) apart to avoid counting individual birds from >1 listening location. The effective area surveyed (EAS) at a listening point is not known, and may vary as a function of land-cover type or other factors. To define the relationship describing distance between vocalizing woodcock and an observer and how cover types influence that relationship, we broadcast a recording of woodcock vocalizations in 2 land-cover types (forest and field) at varying distance. We evaluated the proportion of call broadcasts detected as a function of distance and fit regression curves to detection data to estimate a distance (r*) where the area above the curve at distances <r* was equal to the area under the curve at distances >r*, which allowed determination of the radius of an area where detection probability was effectively 1.0. This EAS had a radius (r*) of 198 m for forest, 384 m for field, and 309 m for both of these land-cover types combined, and an estimated size of 12.3 ha for forest, 46.3 ha for field, and 30.0 ha for both land-cover types combined. We used this information to estimate density of displaying male woodcock based on counts from the SGS in east-central Minnesota that incorporated variation in EAS, probability of detection, survey date, and survey route. Our density estimates (5.0 birds/100 ha in 2009 and 7.1 birds/100 ha in 2010) represent the highest density of singing male American woodcock yet reported, and indicated a substantive increase in density between years.

Detection Probability and Occupancy of American Woodcock during Singing-ground Surveys

Stefanie M. Bergh, David E. Andersen — Tue, 03 Dec 2019 00:00:00 -0600

The Singing-ground Survey (SGS) was designed to exploit the conspicuous breeding-season display of male American woodcock (Scolopax minor; hereafter, woodcock) to monitor these otherwise inconspicuous birds. The SGS was standardized in 1968 and has since been conducted annually to derive an index of abundance and population trend. Counts of singing male woodcock on the SGS have generally declined through time, but without knowledge of the relationship among counts, woodcock abundance, and the factors affecting detection, considerable uncertainty remains in interpretation of SGS data. Using modified SGS protocols, we surveyed SGS routes in Pine County, Minnesota, in 2009 and 2010 and developed models to assess factors associated with detection probability and estimated occupancy. The intercept-only model (i.e., constant detection and occupancy probabilities across sites and no covariates) included overall detection probability of 0.59 (SE = 0.018) in 2009 and 0.66 (SE = 0.017) in 2010 with an occupancy estimate of 0.74 (SE = 0.049) in 2009 and 0.81 (SE = 0.044) in 2010. The best-supported model of detection probability for both years combined included detection as a function of woodcock abundance, observer, date, disturbance level (i.e., ambient noise that interfered with detecting woodcock), and wind speed. High wind speeds were negatively related to detection, different observers had different detection probabilities, date was quadratically related to detection (indicating a mid-period peak in detection), and high woodcock abundance and low disturbance levels were positively related to detection. We provide suggestions for incorporating these resulting into SGS protocol and analyses.

Influence of Weather on the Eurasian Woodcock’s Breeding Display

Christopher J. Heward, Andrew Lowe, Greg J. Conway, Andrew N. Hoodless — Tue, 03 Dec 2019 00:00:00 -0600

Counts of displaying male Eurasian woodcock (Scolopax rusticola) form the basis for breeding Eurasian woodcock surveys in many regions across Europe and provide the only practical method of assessing the species’ abundance. This paper investigates the effect that weather may have on the results of these surveys, principally considering its influence upon Eurasian woodcock display behavior and detectability by surveyors. We assessed data from an annual Eurasian woodcock survey conducted in the Britain during 2004–2015 and correlated them with a number of weather variables. This is supplemented by tracking data gathered from 19 male Eurasian woodcock to assess how weather might affect each individual’s decision to display. We found that counts of roding Eurasian woodcock were positively related to the amount of rainfall in the 2 weeks preceding the survey and negatively related to wind speed on the evenings that surveys were conducted. The likelihood that tagged male Eurasian woodcock displayed decreased in relation to wind speed and increased in relation to minimum air temperature. To guarantee that counts of displaying males provide a representative measure of abundance, we recommend that surveys consist of at ≥3 visits to each site within each year, that visits are spread as widely as possible across the peak displaying season, and that analyses are based on maximal counts rather than means to reduce the effects of surveys conducted in sub-optimal weather conditions.

American Woodcock Singing-ground Survey

Rebecca D. Rau, Thomas R. Cooper, Matthew R. Nelson — Tue, 03 Dec 2019 00:00:00 -0600

The American Woodcock Singing-ground Survey (SGS) is a long-term roadside survey (1968–present) administered by the U.S. Fish and Wildlife Service (USFWS). The SGS was developed to provide indices to changes in American woodcock (Scolopax minor) abundance. The population index derived from the survey is the primary metric used for the United States (US) harvest strategy. Integral to any long-term wildlife-monitoring program (e.g., SGS) with replicated spatial point-count locations is accurate management of metadata related to those locations. Technological advances over the last 20 years have resulted in large-scale coordination and logistical planning changes for the SGS, including improved communication between stakeholders and the creation of a database that houses metadata for all point-count locations. These improvements revealed weaknesses in the historical record-keeping system used for official paper route-maps that may have led to point-count location inconsistencies over time. To summarize the scope of the problem, and make corrections, we compared submitted GPS coordinates for count locations on SGS routes against indicated route paths on official route maps. Across the entire SGS coverage area, we found that 9.9% of observer-submitted point-count coordinates did not match the route path highlighted on the official route maps. We also compared a subset of digitized Minnesota and Wisconsin submitted point-count coordinates and found that 20.9% did not match the route path highlighted on the official route map. We quantified and grouped Minnesota and Wisconsin route-map discrepancies to provide perspective on the types and magnitude of the discrepancies that occur throughout the SGS coverage area. Reasons for the mismatch were many. We share the many challenges of maintaining route consistency and provide recommendations on how to best alleviate route map discrepancies, thus improving the integrity of the SGS and its data.

American Woodcock Singing-Ground Survey Sampling of Forest Type and Age

Tue, 03 Dec 2019 00:00:00 -0600

The American Woodcock Conservation Plan calls for halting and reversing declines of American woodcock (Scolopax minor) populations through creation and management of early successional forest (ESF). Counts of displaying male woodcock along routes of the American woodcock singing-ground survey (SGS) are used to assess regional population status and trends, and there is a need to assess whether SGS routes represent the region. We assessed whether individual SGS routes (330-m buffers) in the Boreal-Hardwood and Prairie-Hardwood Transitions of Minnesota, USA, represented land covers within local landscapes, defined using simulated 10-minute blocks, and whether the routes, in aggregate, represented land covers of our study region. Our land covers included non-forest classes, age-based ESF (20 years), and persisting classes for deciduous-mixed and evergreen forests and woody wetlands. We found that the median value of mean absolute differences (MAD) between percentages for route buffer and block cover classes was 3.78 percentage points. Twenty-two of 81 (27%) route buffers had MAD values 5 percentage points. Within Minnesota, more of these routes (19 of 22) occurred in the Boreal-Hardwood Transition than in the Prairie-Hardwood Transition. Relative to local landscapes, route buffers most frequently and strongly underrepresented open water, barren land, evergreen ESF, persisting woody wetlands, and woody wetland ESF and over-represented developed land and grassland-pasture. When we compared routes in aggregate to our study region, the magnitude of percentage point differences for individual covers did not exceed 5, except for open water. Given the relatively small differences we observed, we conclude that SGS routes well represent land covers within our study region.

Retrospective Analysis of American Woodcock Population and Harvest Trends in Canada

Tue, 03 Dec 2019 00:00:00 -0600

We used data from the Canadian component of the annual American Woodcock Singing-ground Survey (SGS) and data from the Canadian National Harvest Survey between 1975 and 2015 to assess temporal fluctuations in the population index, the number of American woodcock (Scolopax minor; hereafter, woodcock) harvested in Canada, and the proportion of successful hunters in Canada. We performed analyses via generalized additive mixed models that allowed us to identify periods when there were significant changes in temporal trends, and years during which there were signiﬁcant changes in the direction of the temporal trajectory. We included climatic conditions before, during, and after the nesting and brood-rearing seasons (i.e., prior to the hunting season) as explanatory variables in our model. We did not find any effect of climatic variables on the SGS index. The SGS population index showed a slow overall negative decline in Canada, but there were only 2 significant periods of decline (1978–1984 and 1992–1994). Woodcock harvest and the proportion of successful woodcock hunters increased with the size of the SGS population index in the spring. The total harvest and the proportion of successful hunters remained fairly stable during the study period, but both indices showed a period of significant decline that started ca. 2006, and that was followed by a period of significant increase that started ca. 2009.

Survey of Wintering Eurasian Woodcock in Western Europe

Tue, 03 Dec 2019 00:00:00 -0600

The Eurasian woodcock (Scolopax rusticola) is a mostly migratory wader (Charadriiformes) that is broadly distributed across the Palearctic. This species winters in or migrates through all European countries and is an important quarry species in many of them. Sustainable management of the species requires information regarding abundance and demographic parameters to be collected regularly. This is a complex task given that different phases of its annual life cycle occur in different countries and, due to the species’ secretive behavior, Eurasian woodcock populations cannot be properly evaluated by common bird-census techniques. In Europe, woodcock hunters from different countries have joined in the Federation of Western Palearctic Woodcock Associations (FANBPO), collecting data on hunting activity that can be used to annually evaluate relative abundance and demographic parameters. To investigate variation in Eurasian woodcock relative abundance during and between hunting seasons, we fitted generalized additive mixed models (GAMMs) to data collected in France, Spain, and Portugal (Franco-Iberian region; 2006–2007 to 2015–2016) to analyze the variation in the number of different Eurasian woodcock seen per hunting trip. For these countries and for Switzerland, Italy, Ireland, and Wales, we also analyzed demographic parameters (the ratios of female:male and juvenile:adult) from bagged birds. In the Franco-Iberian region the relative abundance during the autumn-winter period increased from September to the beginning of December, and remained high thereafter with a slight decrease until the end of February; in the last 10 years, relative abundance has remained stable during autumn migration and winter. The sex ratio remained stable in the Swiss-Franco-Iberian and Swiss-Italian regions, but the former had a higher proportion of females. The age ratio varied among hunting seasons and regions. This research is an example of the effective use of data collected through citizen science that aims to maintain a favorable conservation status of the Eurasian woodcock while allowing a rational use of its populations via sustainable and controlled hunting.

American Woodcock Priority Information Needs – A Shared Vision

Dave J. Case, Thomas R. Cooper — Mon, 02 Dec 2019 00:00:00 -0600

Implementing the American Woodcock Conservation Plan

Steven Weber, Thomas R. Cooper — Mon, 02 Dec 2019 00:00:00 -0600

American Woodcock Status

Mark Seamans, Rebecca Rau — Mon, 02 Dec 2019 00:00:00 -0600

Annual assessment of American woodcock (Scolopax minor; hereafter, woodcock) populations in North America relies primarily on the American Woodcock Singing-Ground Survey (SGS). Ancillary information concerning harvest and hunting effort comes from the Harvest Information Program (HIP), and indices of recruitment come from Wing Collection Surveys (WCS). We report on long-term trends in SGS, HIP, and WCS data in the Eastern and Central Management Regions in the U.S. Analyses of SGS data indicate there have been significant long-term (1968–2017) declines of 1.05% per year in the Eastern Management Region and -0.56 % per year in the Central Management Region. Discontinuance of some routes and their replacement with new routes may have artificially lessened the long-term negative trends in the SGS. Since 2013, total harvest and number of days hunters spent pursuing woodcock have been below the long-term average (1999–2015) in both management regions. Age ratios (number of immatures per adult female) were temporally variable but exhibited no long-term trend in the Eastern Management Region. In the Central Management Region, age ratios were generally higher during the beginning of the study (1963–1987) period versus the latter part (1988–2016).

Wooden Spoons for Woodcock

Bill O'Neill, David Neumann, Jagdish Poudel — Mon, 02 Dec 2019 00:00:00 -0600

The American woodcock (Scolopax minor; hereafter, woodcock) is an important game species in central and eastern North America. In this paper, we argue that the wildlife community should consider several novel ideas. At the landscape level, one of the most effective ways to perpetuate aspen (Populus spp.) forests is through commercial forest management. Aspen underpins the major forest products industries: its fiber is highly sought after for pulp, paper, oriented strand board and other engineered lumber products, and lumber. The most cost-effective and reliable way to maintain woodcock habitat is through commercial forest management and through periodic timber harvests. Non-commercial habitat management is possible but expensive and time consuming. Support for forest products industry business attraction and development is good for woodcock habitat, good for local communities, and good for local economies. We recommend that the wildlife community consider greater involvement in the broader social discussion over the use of wood products, and be actively engaged in discussions involving economic development and energy use by the forest products industry at the state and local level.

The Future of Woodcock

Russ Mason, John Eichinger — Mon, 02 Dec 2019 00:00:00 -0600

We welcome you to Roscommon, Michigan for this 2017 symposium. What a prime location to host a meeting of this caliber and to expand partnerships for this unique bird. It is crucial that we work together to conduct research and exchange information at meetings like this. Many people helped to make this symposium a reality and we thank all the committee members for their contributions. We especially thank symposium chairs for their diligence and leadership. Since the last symposium, in 2006, there has been considerable work in woodcock research, management, and conservation. Collectively, these efforts have helped to arrest the decade-long downward trend in woodcock populations. We continue to be optimistic about the outlook for woodcock. We believe that substantive long-range strategic planning and expanded partnerships will be key to improving the status of American woodcock in the future.

Welcome to Michigan and the 11th American Woodcock Symposium

Al Stewart — Tue, 26 Nov 2019 00:00:00 -0600

Association between American Woodcock Seasonal Productivity and Landscape Composition and Configuration in Minnesota

Gunnar R. Kramer, Kyle O. Daly, Henry M. Streby, David E. Andersen — Mon, 02 Dec 2019 00:00:00 -0600

The effects of landscape composition and configuration on productivity of most bird species, including American woodcock (Scolopax minor), are largely unknown. Understanding landscape components and cover-type configurations associated with productivity can be useful in developing more effective management strategies that increase recruitment. We used data on nest and juvenile survival rates of American woodcock from northern Minnesota from 2011 and 2012 to inform logistic exposure models of survival and predict productivity through the period when juveniles are capable of sustained flight (~15 days post-hatch). We used those models to link landscape features with nest survival rate and juvenile survival rate, predict spatially explicit productivity across our study area, and identify areas of high productivity within our study landscape. Lastly, we used simulations to explore the consequences of potential management actions aimed at improving productivity and the effects of long-term succession of young-forest cover types. We found that associations between land-cover composition and different components of productivity (i.e., nest and juvenile survival rates) were scale-specific. Generally, our models suggested stand-level composition (i.e., the amount of each cover type within 250–500 m of the nest) influenced nest survival rate, with mature forest having a small but mostly positive association with nest survival rate in most landscape contexts. Conversely, our models predicted lower nest survival rates in landscapes with greater amounts of grassland and upland shrubland. The amounts of wetland shrubland and upland shrubland at stand- (i.e., 250–500 m) and landscape-level (i.e., 1,000 m) scales were positively associated with juvenile survival rate. Our findings demonstrate that the effects of management actions depend on the context and configuration of cover types within the surrounding landscape and that spatially explicit models of productivity may be useful for informing management strategies. Furthermore, our results suggest that relationships between survival and specific land-cover types may change throughout the reproductive cycle in American woodcock.

American Woodcock Migration Ecology

Mon, 02 Dec 2019 00:00:00 -0600

Migration may expose birds to hazards at intensities greater than those during any other life stage, and effective conservation of migratory species requires an understanding of space use during migration. From 2010 to 2013 we conducted a radio-telemetry study of American woodcock (Scolopax minor) on the Cape May Peninsula, New Jersey, which is an important stopover site for migratory woodcock in the eastern flyway. Our research objectives were to 1) describe diurnal cover-type characteristics used by woodcock, 2) evaluate second-order habitat selection during the fall migration period, 3) evaluate drivers affecting timing of departure of woodcock from stopover sites, and 4) determine age- and sexspecific departure rates. We nightlighted fields to capture birds and attach VHF radio-transmitters. Over 4 years we radiomarked 271 woodcock and collected 1,949 GPS point locations from these birds (Range = 0–21 points per individual). We used GIS and resource selection functions in the form of generalized linear mixed models to compare land cover-type attributes at the marked locations (used) to attributes at random locations distributed across our study landscape (available). Our model shows a strong negative effect on selection as distance from fields increases, avoidance of large contiguous forest, and selection for forested wetlands. We used results from this analysis to develop a predictive model of habitat distribution at Cape May. To complete objective 3 and 4 we used a CJS survival analysis framework, where results from objectives 1 and 2, as well as weather and astrological variables, were used as covariates to model timing of departure. Our study improves understanding of American woodcock habitat selection during this critical life stage and provides a predictive model for understanding timing of departure from a migratory stopover. Furthermore, our results may identify important habitats for other short-distance migrants that rely on early successional habitat.

Landscape Context Matters When American Woodcock Select Singing Grounds

Stephen J. Brenner, Bill Buffum, Brian C. Tefft, Scott R. McWilliams — Mon, 02 Dec 2019 00:00:00 -0600

The multiscale nature of habitat selection during the breeding season for migratory birds means that core-use areas (e.g., breeding territories) are selected based on their local habitat features, but these may also be influenced in some way by features within a larger-scale landscape. We conducted a reciprocal transplant experiment to test the hypothesis that habitat selection and movements of male American Woodcock (Scolopax minor) in core-use areas during the breeding season depend on the perceived quality of the surrounding landscape. We captured second-year male woodcocks (n = 19) at high- or low-likelihood-of-use landscapes in Rhode Island, USA, affixed each with a radio transmitter, relocated them to the opposite type of landscape, and then determined if they returned to their original site of capture or remained in the landscape to which they were relocated. Birds captured in high-likelihood landscapes and moved to low-likelihood landscapes generally returned to their original high-likelihood landscape (5/7, 71%), but birds captured in low-likelihood landscapes and moved to high-likelihood landscapes rarely returned to their original low-likelihood landscape (1/12, 8%). These results support the hypothesis that woodcock assess their surroundings relatively rapidly and subsequently make critical settlement decisions based on landscape composition. Given that woodcock choice is predicted by the woodcock- specific resource selection function, these results also provide support for the use of this tool to guide forest management for woodcock.

Evaluation of Habitat Characteristics and the Appropriate Scale for Evaluating Diurnal Habitat Selection of Wintering American Woodcock in Louisiana

Elisa C. Elizondo, Jeffrey P. Duguay, Bret A. Collier — Mon, 02 Dec 2019 00:00:00 -0600

Migratory bird species pose serious management challenges because it is difficult to determine habitats utilized during their entire life cycles. As American woodcock populations have experienced long-term declines, wintering habitat management has become increasingly important. Past studies on woodcock have relied predominantly on Very High Frequency (VHF) telemetry, which require an observer to manually track them to gather location information. Our study employed both Global Positioning System (GPS) and VHF tags on woodcock to gather high resolution movement data in order to evaluate habitat use and compare VHF and GPS approaches to habitat sampling. We simulated a VHF approach to tracking the same individuals from the GPS tag data (spanning 252 bird-days) and utilized vegetation samples from our VHF tracked birds to evaluate use and random paired location sampling. We found that many random locations fell within the Minimum Convex Polygons (MCP) as defined via the GPS tags (average diurnal MCP size was 0.04 ha). Overall, our results suggest that evaluating resource selection by woodcock requires discerning the appropriate scale(s) of habitat selection via the identification of the spatial and temporal components underlying individual movement ecology.

Enhancing Nocturnal Habitat for the American Woodcock on Louisiana Wintering Grounds

James C. Haynes, Jeffrey P. Duguay, Kim Marie Tolson — Mon, 02 Dec 2019 00:00:00 -0600

American woodcock (Scolopax minor; hereafter, woodcock) have experienced long-term population declines across much of their breeding distribution since 1968. Previous research suggests that nocturnal habitat availability on the wintering grounds is important to wintering woodcock survival. We compared 4 different land management techniques: mowing, burning, disking, and a mow/burn combination for enhancing nocturnal habitat for woodcock in south-central Louisiana. From 2011–2013, we monitored study plots during overcast nights throughout winter months. We detected woodcock most frequently in both the burn and mow treatments and least frequently in the disk treatment. The total numbers of woodcock we captured and flushed were 13 times greater in the burn treatment than in the disk treatment. We captured 24 times more juvenile woodcock in the mow and burn treatments than in the disk treatment. We captured 12 times more female woodcock in the burn treatment than in the disk treatment, whereas we captured 9 times more male woodcock in the mow treatment than in the disk treatment. Our results suggest that suitable nocturnal habitat for woodcock on the wintering grounds in south-central Louisiana can be enhanced by burning and/or mowing.

Migration Timing, Routes, and Connectivity of Eurasian Woodcock Wintering in Britain and Ireland

Andrew N. Hoodless, Christopher J. Heward — Mon, 02 Dec 2019 00:00:00 -0600

Migration represents a critical time in the annual cycle of Eurasian woodcock (Scolopax rusticola), with potential consequences for individual fitness and survival. In October–December, Eurasian woodcock migrate from breeding grounds in northern Eurasia over thousands of kilometres to western Europe, returning in March–May. The species is widely hunted in Europe, with 2.3–3.5 million individuals shot per year; hence, an understanding of the timing of migration and routes taken is an essential part of developing sustainable flyway management. Our aims were to determine the timing and migration routes of Eurasian woodcock wintering in Britain and Ireland, and to assess the degree of connectivity between breeding and wintering sites. We present data from 52 Eurasian woodcock fitted with satellite tags in late winter 2012–2016, which indicate that the timing of spring departure varied annually and was positively correlated with temperature, with a mean departure date of 26 March (± 1.4 days SE). Spring migration distances averaged 2,851 ± 165 km (SE), with individuals typically making 5 stopovers. The majority of our sample of tagged Eurasian woodcock migrated to breeding sites in northwestern Russia (54%), with smaller proportions breeding in Denmark, Scandinavia, and Finland (29%); Poland, Latvia, and Belarus (9.5%); and central Russia (7.5%). The accumulated migration routes of tagged individuals suggest a main flyway for Eurasian woodcock wintering in Britain and Ireland through Belgium, the Netherlands, and Germany, and then dividing to pass through the countries immediately north and south of the Baltic Sea. We found a weak positive relationship between breeding site longitude and wintering site latitude, suggesting broadly parallel migration routes from distinct breeding areas but some mixing of individuals from different breeding areas at the same wintering site.

Survival Rates and Stopover Persistence of American Woodcock Using Cape May, New Jersey, during Fall Migration

Mon, 02 Dec 2019 00:00:00 -0600

Cape May, New Jersey is an important stopover area for American woodcock (Scolopax minor,; hereafter woodcock) during fall migration along the Atlantic Coast of the United States. Previous research has indicated that many woodcock stop at Cape May prior to crossing Delaware Bay; however, little is known about survival of woodcock while using Cape May. To better understand woodcock survival on Cape May during fall migration and to estimate emigration rates for woodcock migrating through Cape May, we captured and marked a total of 271 woodcock with VHF transmitters and radio-tracked them weekly from November through early January 2010-–2013. Of the 271 marked woodcock, our radio-tracking efforts indicated that 131 migrated from Cape May, 57 remained on Cape May, 72 died, and 11 were censored. We used a multi-state model within Program MARK to estimate weekly survival and emigration probabilities for marked woodcock. Our best-supported model indicated that survival rate varied by year, but was constant by week within years. Weekly survival rate estimates ranged from 0.894 (95% CI = 0.834 – 0.934) in 2010 to 0.962 (95% CI = 0.928 – 0.981) in 2011, which equates to a 9-week period survival rate ranging from 0.365 (95% CI = 0.185 – 0.545) to 0.706 (95% CI = 0.541 – 0.870), respectively. The 2010–-2011 field season was marked by several large snowstorms during which a large percentage of marked woodcock died, whereas the other 3 years had more mild conditions and higher woodcock survival rates. Our best-supported model indicated that weekly emigration rates varied by year and week, with each year showing a different pattern of emigration from Cape May. Survival and emigration information will be useful in the development of future demographic-based population models for woodcock migrating along the Atlantic Coast.

Using Pointing Dogs and Hierarchical Models to Evaluate American Woodcock Winter Occupancy and Densities

Daniel S. Sullins, Warren C. Conway, David A. Haukos, Christopher E. Comer — Mon, 02 Dec 2019 00:00:00 -0600

Use of dogs has increased for multiple wildlife research purposes ranging from carnivore scat detection to estimation of reptile abundance. Use of dogs is not particularly novel for upland gamebird biologists, and pointing dogs have been long considered an important research tool. However, recent advances in Global Positioning System (GPS) technology and the development of hierarchical modeling approaches that account for imperfect detection may improve estimates of occupancy and density of cryptic species such as the American woodcock (Scolopax minor; hereafter, woodcock). We conducted surveys for woodcock using a trained pointing dog wearing a GPS collar during the winters of 2010–2011 and 2011–2012 in East Texas, USA. We surveyed 0.5-km-radius circular plots (n = 24; survey sites) randomly placed along secondary roads in Davy Crockett National Forest and on private timber property. Surveys lasted 1.5 hrs and were repeated 3–5 times each winter. We estimated woodcock occupancy and density using multiple modeling approaches at the survey site and forest stand scales within survey sites. Woodcock occupied 88% (21/24) of survey sites and 48% (39/82) of forest stands (i.e., unique cover types) within sites. Using a modified distance sampling technique, we estimated an average density of 0.16 birds/ha (SE = 0.13) throughout both study areas. We describe the first attempt to blend use of pointing dogs with hierarchical modeling approaches to derive estimates of regional diurnal woodcock occupancy and density, and describe relationships between these estimates of abundance and habitat covariates. Although forest stand occupancy estimates had the lowest coefficients of variation, our estimates of density provided the most useful inference of habitat use. Surveys using pointing dogs paired with hierarchical models of occupancy and density may provide a cost-efficient and effective approach to estimate habitat abundance at broad spatial scales.

Habitat Selection of American Woodcock and its Implications for Habitat Management Where Young Forests are Rare

Roger J. Masse, Brian C. Tefft, Bill Buffum, Scott R. McWilliams — Mon, 02 Dec 2019 00:00:00 -0600

American woodcock (Scolopax minor; hereafter woodcock) habitat use or selection has been studied extensively since the mid-1960s; most such studies, however, have taken place when and where young forest habitat selected by woodcock was relatively common. Woodcock population declines have been mostly attributed to loss of young forest vegetation types throughout the species’ range. Thus, understanding woodcock habitat selection and the benefits of habitat management in areas where young forests are rare is important in conserving woodcock and other wildlife that uses young forest. We conducted studies of male radio-tagged woodcock in Rhode Island, USA, when and where the extent of upland young forests in non-coastal areas comprised only 1.4% of the land area and was decreasing by ≥1.5% per year. We determined habitat selection of woodcock, then used the derived resource selection function to assess potential benefits of certain forest management scenarios for male woodcock and non-target birds. Landscapes comprising deciduous wetland forests, wetland young forests with nearby agricultural openings, or patches of upland young forest received relatively high use by woodcock. After integrating habitat management scenarios into GIS, our derived resource selection function suggested that creating fewer, larger patches of upland young forest and herbaceous forest openings may be less beneficial than creating more smaller patches. Openings with early-successional forest were an important component of woodcock habitat because they provided safe nighttime roost sites where mammalian predators were less active. These openings also provided habitat for a more diverse bird assemblage than unmanaged forests. Active habitat management is required to conserve woodcock populations in many landscapes, and managers should highlight the benefits of woodcock habitat management for non-target wildlife.