Birds

Poster

  • Male Eastern Wild Turkey Survival in Delaware*
  • Drake A. Hardman; Angela Holland; Jacob M. Haus; Justyn R. Foth; Jacob L. Bowman
    Knowledge of the population dynamics for Eastern wild turkey (Meleagris gallopavo silvestris) males provides managers with data to set harvest quotas. Although state agencies can estimate or track the number of birds harvested each year, the actual proportion of the population that is harvested remains unknown. Additionally, the amount of mortality experienced throughout the year outside of hunting season is unknown and could have an impact on harvest quotas. Our objective is to determine the survival rates of adult and juvenile wild turkeys throughout the year in Delaware. We captured 98 wild turkeys (65 juveniles, 33 adults) over two seasons on both public and private property in Delaware. We fitted all males with remote-download GPS transmitters and 2 rivet style leg bands (1 on each leg). Transmitters had an 8-hour mortality switch and we checked birds weekly to download location data. We will use a Kaplan-Meier procedure to estimate survival rates and compare survival between age classes using a log-rank test. We will compare estimated survival rates to harvest rates calculated from band returns to determine if it is a viable method for estimating harvest rates during the spring. Survival data will also allow us to determine if hunters are selectively harvesting birds based on age class, and if adults or juveniles are more susceptible to sources of mortality beyond hunting. This research will help managers better inform their harvest management, while ensuring that future generations can view and hunt wild turkeys.

  • Managing Wildlife Openings to Benefit Game and Non-Game Bird Species in Central Appalachian Forests*
  • Hannah L. Clipp; Christopher T. Rota; Petra B. Wood
    In forested landscapes of the Central Appalachians, wildlife openings created and maintained by land managers provide habitat and food resources for disturbance-dependent, early-successional game species, such as wild turkey (Meleagris gallopavo), ruffed grouse (Bonasa umbellus), and American woodcock (Scolopax minor). Though managers tend to focus on these three game birds, wildlife openings can also benefit a myriad of avian species and guilds, depending on local habitat features and landscape-level factors. Yet little effort has been made to investigate how to optimally manage wildlife openings to attract a full spectrum of avifauna throughout spring and summer and maximize richness across habitat guilds. Therefore, the purpose of this study is to examine the sympatric use of wildlife openings by game birds, breeding songbirds, and post-breeding songbirds in response to site- and landscape-level wildlife opening characteristics. Our objectives are to determine how local habitat attributes, opening size, management actions, and landscape context relate to (1) avian guild richness, (2) occupancy of specific game birds, breeding songbirds, and post-breeding songbirds, and (3) abundance of specific early-successional, edge-associated, and forest-interior breeding songbird species in wildlife openings. In April-August 2019-2020, we used species-specific and community-wide point count surveys, acoustic recorders, game cameras, and transect surveys to sample the avian communities of 115 wildlife openings within the Monongahela National Forest in eastern West Virginia. Data collection and statistical analyses are ongoing, but preliminary results from multi-species occupancy and n-mixture models have identified influential site and landscape variables and indicated their relationships with avian guild richness and focal species occupancy and abundance. Ultimately, these results will assist in the design and management of wildlife openings that simultaneously support target game bird populations and promote a diverse suite of songbirds.

  • The Timing and Abundance of Hawk Migration along the Southern Shore of Lake Erie Over 15 Years
  • Auriel M.V. Fournier; Marck C. Shieldcastle
    Avian migration is a widely observed and appreciated phenomenon that is currently shifting for many species in response to climate change. Assessing how or if species are changing their migratory strategies is vital to understanding how those species might adapt to a warmer world, and the other factors, such as spring green up, or the breeding season of prey, that may also be shifting at a local or regional scale. We monitored hawks in northwestern Ohio on the shore of Lake Erie for 15 years to assess changes in the timing and abundance of several hawks species during spring migration. We observed over 150000 individuals and did not find any differences in timing for any species, when examining the 10th, 50th or 90th percentiles of the migratory window. We did find small increase in Bald Eagles, as well as small decreases in American Kestrels. As diurnal migrants, hawks face a different set of challenges during migration, and may be impacted differently by climate change as a result.

  • Breeding Season Home Range and Resource Use of Two Subspecies of Translocated Bobwhite
  • Elizabeth Brogan; John Palarski; Heather Mathewson; Bradley Kubecka; Dale Rollins
    The decline of the northern bobwhite (Colinus virginianus) has resulted in regional extirpation across its range. Within the Cross Timbers ecoregion of Texas, this decline is evident and remnant populations exist across a fragmented landscape. To reverse this decline, translocation has emerged as a possible solution to restock remnant populations in restored habitat. In some cases, individuals for translocation are translocated long distances and sourced from different subspecies. As a result, differences in natal environments may influence resource use on release sites. Woody cover is an important component of bobwhite habitat, but its use varies geographically. Furthermore, large movements post-release may influence survival. Our objectives were to 1) quantify home range size of two subspecies of translocated bobwhite, and 2) compare woody cover use for each subspecies. We hypothesize that bobwhite sourced from south Texas (C. v. texanus) will use a greater percentage of woody cover (fourth order selection) than bobwhite from west Texas (C. v. taylori) due to its greater abundance in that region. During March 2019 and 2020, we translocated 167 and 236 wild-trapped bobwhites, respectively, to a 1,011 ha area in central Texas. We fit 111 (n = 56 C. v. taylori; n = 55 C. v. texanus) and 110 (n = 46 C. v. taylori; n = 64 C. v. texanus) individuals with VHF transmitters in 2019 and 2020, respectively. We obtained GPS locations for all individuals 3-5 times per week immediately post-release. We will calculate kernel density estimates of home range and use generalized linear models to estimate woody vegetation use for each subspecies. Findings from this study will be used to aid managers who wish to translocate bobwhite of various subspecies.

  • Examining Ruffed Grouse Drumming Log Position and Drumming Direction as it Relates to Home Range
  • Logan Cutler; Brady Roberts; Phillip Maguire; Catrina Johnson
    Ruffed grouse (Bonasa umbellus) are an important game species throughout the Great Lakes region. Males perform a unique mating display called drumming, atop fallen logs to attract females and maintain their territory throughout the spring. Due to the cryptic nature of these dense woodland birds, they can be difficult to survey. One of the most common ways to do so is by using auditory drumming surveys, similar to point count surveys, during their mating season. Members of the UW-Stevens Point Ruffed Grouse Project have been conducting auditory drumming surveys in Northern Wisconsin since 2014. Information from these surveys were used to locate drumming logs. Mirror box traps were then placed on these logs to capture and collar male ruffed grouse. Home ranges were developed with triangulated telemetry locations and constructed in ArcGIS Pro. This study aims to examine the position of known drumming logs within these home ranges, and couple that with the orientation of drumming. With these two metrics, the breeding ecology of male ruffed grouse can be better understood, and more effective survey methods can be developed. Initial results show that most drumming logs were located within 10 meters of the edge of the home range. Additionally, most drumming faced out of the home range. Because of these results, ruffed grouse may use drumming logs as a territory marker, attracting outside females and discouraging other males from entering their territory.

  • Habitat Selection and Breeding Ecology of Bachman’s Sparrow in a Wiregrass-Free Ecosystem*
  • Mikayla R. Thistle; Jamie Dozier; Mark A. McAlister; Beth E. Ross
    Through much of its range, Bachman’s Sparrow (Peucaea aestivalis) uses the wiregrass (Aristida sp.) dominant understory typical of longleaf pine (Pinus palustris) forest. The central South Carolina Coastal Plain, however, lies within the “wiregrass gap” where longleaf pine understories are absent of wiregrass and have greater shrub density. Habitat use of Bachman’s Sparrow in this unique region has yet to be studied and declining Bachman’s Sparrow populations necessitate a better understanding of habitat selection processes and population dynamics across regional habitat types. The goal of this ongoing study is to describe breeding season habitat use and breeding ecology of Bachman’s Sparrow in the unique wiregrass-free longleaf pine ecosystem of Tom Yawkey Wildlife Center and Santee Coastal Reserve, South Carolina, to inform best management practices for Bachman’s Sparrow. After the first of two planned seasons of data collection (April 1 – July 31, 2020 and 2021), we use N-mixture models in a preliminary analysis to estimate the effects of habitat management treatments (e.g., prescribed burning and stand thinning) and patch structure on Bachman’s Sparrow density. We identify vegetation and structural characteristics that Bachman’s Sparrows select for nest sites by comparing nest-site features to available locations within the home range. To determine if habitat selection in our study population is adaptive, we monitor nests and fledglings until independence, calculate daily survival rates using logistic exposure models, and relate nest-site and home range selection to reproductive success. Finally, we explain how our results will be used to inform region-specific management plans and restoration of degraded habitats, which also lack typical vegetation composition, to encourage Bachman’s Sparrow survival, recruitment, and nesting success.

  • Depletion Rates of Flooded, Unharvested Corn in Western Tennessee*
  • Cory J. Highway; Abigail G. Blake-Bradshaw; Nicholas M. Masto; Jamie C. Feddersen; Heath M. Hagy; Daniel L. Combs; Bradley S. Cohen
    Management of wintering areas for non-breeding waterfowl necessitates provision of forage to meet the energetic demands associated with recovering from autumn migration, maintaining body condition during winter, and preparing for spring migration. Wetland managers are often tasked with providing energy-rich foods and making them available for waterfowl during the winter. Some waterfowl species such as the mallard (Anas platyrhynchos), readily forage on available agricultural seeds to meet their energy requirements. Thus, calorie-dense agricultural seeds readily consumed by waterfowl such as corn (Zea mays), grain sorghum (Sorghum bicolor), millet (Echinochloa spp.), and soybeans (Glycine max), are often planted by wetland managers to supplement waterfowl diets and meet energetic demands of wintering waterfowl. In western Tennessee, flooding unharvested corn is a popular management tool used by hunters and wildlife managers to attract and provide energy for waterfowl. However, the degree of utilization and depletion of flooded, unharvested corn by waterfowl during winter is relatively unknown. We measured corn depletion by repeatedly surveying 30 flooded, unharvested corn fields at two-week intervals throughout the winter (October-February), to estimate and determine the factors influencing depletion of flooded, unharvested corn. We will develop a model for depletion of flooded, unharvested corn to help estimate carrying capacity for waterfowl and better understand the movements of mallards in relation to food resources in the region. Likewise, our estimates of factors influencing depletion rate of flooded, unharvested corn will allow wetland managers to plan spatial and temporal distribution of this resource to ensure availability across the wintering period.

  • An Assessment of Factors Influencing Nest Survival of Emperor Geese on Yukon Delta National Wildlife Refuge, Alaska*
  • Jordan Thompson; Benjamin Sedinger; Bryan Daniels
    Emperor geese (Anser canagicus) are a unique marine species endemic to coastal Alaska and Russia. Following significant population declines, both subsistence and sport harvest of emperor geese in Alaska were closed in the mid 1980’s. After a gradual population increase spanning 30 years, subsistence and limited sport harvest were reopened in 2017. To ensure the population remains at a harvestable level, it is important to understand drivers of variability in vital rates that may limit their population growth rate, including reproduction. Nest survival is an important component of reproduction in waterfowl and is primarily driven by predation in emperor geese. A variety of factors may influence nest survival of emperor geese by increasing or decreasing vulnerability of their nests to predation. The objectives of this study are to estimate nest survival rates of emperor geese on Kigigak Island within Yukon Delta National Wildlife Refuge, Alaska, evaluate factors that influence their nest survival, and compare contemporary nest survival estimates to historic estimates to examine potential long-term shifts in nest survival. To address these objectives, emperor goose nests on Kigigak Island have been monitored from 2017-2019 and will be monitored in 2021. We will use these data to develop models to estimate daily nest survival rates and evaluate the influence of nesting phenology, nest site characteristics, climate, and observer visits on daily nest survival. Preliminary results will be reported. Results from this study will help elucidate factors driving variability in nest survival rates of emperor geese and identify management actions to increase population growth rates and maintain the population at a harvestable level.

  • Migratory Behavior in Dark-Eyed Juncos in Berkshire County, Massachusetts*
  • Hannah Wait; Dr. Daniel Shustack
    Junco hyemalis (Dark-eyed Junco) is a widespread songbird in North America and is observed year-round in Berkshire County, Massachusetts. Questions remain regarding its migratory behavior. We used deuterium ratios from secondary flight feathers to assess migratory behavior of juncos found in western Massachusetts and to determine the breeding locations of sampled individuals. Male juncos (N=7) captured during the summer displayed deuterium ratios of -67 to -52 dD. Overwintering male juncos (N=3) had dD ratios between -115 and -105. Deuterium ratios in precipitation suggest male juncos overwintering in Berkshire County traveled from breeding grounds in northern Canada. Juncos captured during migration had dD values between the values of the summer breeders and overwintering males, suggesting that juncos from across the breeding range north of Berkshire County migrate through our study area. We continued sampling during the winter of 2019-2020 in order to fully describe isotopic values from overwintering juncos.

  • Assessment of Ticks on Birds in Northern Berkshire County, Massachusetts*
  • Noah Henkenius
    Birds are important in the dispersal of ticks and the diseases they carry. During migration, birds can travel considerable distances over a few days. In North America, several tick species that parasitize birds will also feed on mammalian hosts, including humans. This creates a pathway for diseases carried by birds to be transmitted to human through a mutual common parasite. If birds can successfully carry exotic tick species during migration, they could assist their establishment in new regions, potentially leading to the introduction of unfamiliar diseases. In 2018 and 2019 during the migration and breeding season we used mist nets to sample songbirds for ticks in a mixed hardwood forest in northern Berkshire County, Massachusetts. After ticks were collected from birds, they were stored in microcentrifuge tubes with 70% ethanol for later identification using dichotomous keys. Our goals were to assess if ticks were prevalent on birds throughout the breeding season and to determine if birds could be introducing exotic tick species to the region. We hypothesize that exotic tick species would only be found on neotropical migrants, and native tick species will readily parasitize birds throughout the breeding season. Our results suggest immature stages of Ixodes scapularis are the most common ticks to parasitize birds in our study site. In 2018 we found that male birds had a slight tendency to have higher infestation rates (37.3%; 28/75) than females (29.5%; 13/44). Our results also suggest that ticks were prevalent on birds throughout the breeding season.

  • A Thirteen Year Study of Wintering Birds in Sandhill Wildlife Area, Wisconsin*
  • Mackenzie Leigh Whitney
    Many wintering bird species occupy the Sandhill Wildlife Area (SHWA) in Babcock, Wisconsin. The southwest corner of SHWA is composed of oak (Quercus spp.) and aspen (Populus spp.) ranging in age from 15 to 75 years. The University of Wisconsin-Stevens Point’s student chapter of The Wildlife Society has sponsored a student woodpecker research project from 2007-2020 at SHWA. Hairy (Picoides villosus), downy (P. pubescens), and red-bellied woodpeckers (Melanerpes carolinus), as well as white-breasted nuthatches (Sitta carolinensis), have been captured to investigate home range size during the winter months. These birds are trapped in a 31.5 hectare grid of wire tree traps and caught between January and March annually. These birds are then tagged with a United States Geological Survey (USGS) aluminum band. Home ranges were determined using the Minimum Convex Polygon estimator in ArcGIS. Recapturing these birds creates an opportunity to observe the fluctuations in individual home range size, weight, and fidelity over an extended period of time.

  • Using Citizen Science Data to Validate Habitat Suitability Assumptions in Waterfowl Conservation Planning
  • Drew N. Fowler; Jessica A. Jaworski; Matthew D. Palumbo
    Determining the spatial distribution and density of a species is an important component of conservation planning. Further, understanding the landscape habitat characteristics that influence species occurrence and density aide in more informative modeling to guide planners. In the case where empirical species occurrence data are lacking, distribution models are based on assumptions of site occupancy provided that certain habitat features are available at a location. In these cases, the accuracy of spatial distribution is dependent on the ability of pre-specified habitat features to correctly predict species occupancy. For species that are seasonally present in a landscape, like migratory waterfowl, predicting spatially explicit occupancy using habitat features has historically been challenging because of limited spatially extent of available data. Our goal was to use citizen science collected data (eBird) to model Ring-necked duck (Aythya collaris) spatial distribution and occupancy in Wisconsin during spring migration and the summer breeding period to validate existing assumptions of habitat suitability characteristics established by the Upper Mississippi River / Great Lakes Joint Venture (UMRGL JV). We followed established best practices for using eBird data and filtered observations from complete checklists across Wisconsin from March through April (spring) and May through August 15th (summer) of 2009-2019. We established a 2.5 km by 2.5 km buffer around each unique checklist location and calculated the proportion of the landscape of each distinct land cover type using National Wetland Inventory polygons and a state specific landcover database (WISCLAND 2). We used landscape covariates as well as variables to describe observer effort to model encounter rate and site occupancy during the two distinct seasons. Lastly, we compare our models to distribution and abundance models of Ring-necked ducks recently derived in the Wisconsin Waterfowl Habitat Conservation Strategy that relied on habitat suitability assumptions established by conservation planners.

  • The Role of Habitat Diversity in Structuring Avian Communities on Wetland Reserve Program Easements in the Mississippi Alluvial Valley*
  • Jon Podoliak; David Hicks; Lisa Webb
    Bottomland hardwood (BLH) forests were once the dominant ecosystem in the Mississippi Alluvial Valley (MAV), however conversion for agricultural purposes reduced the area of BLH forest across the MAV by 75%. Due to wetland loss and subsequent effects on biotic communities and water quality, the Wetland Reserve Program (WRP) was initiated in 1990 to restore marginal agricultural lands to wetlands. The purpose of our project is to evaluate the effectiveness of WRP restoration projects at providing habitat for wetland dependent taxa in the MAV. We sampled avifauna and vegetation at 20 WRP easements in western Tennessee and Kentucky in fall 2019 and winter 2020. Sampling will continue in Spring 2020 and an additional 20 sites will be sampled during 2020-21. We classified habitats on easements into four categories: remnant forest, planted forest, naturally regenerated forest, and shallow water area (SWA). Preliminary data indicate avian species richness was greater at sites with more habitat types (Rho = 0.49, p = 0.001, R2 = 0.2). Across seasons, total species richness on-easement ranged from 4 to 16 species. Combined avian species richness from both sampling periods was significantly different among habitat types (F= 7.124, p = 0.00102), and specifically remnant forest communities had greater species richness compared to planted forest communities (p = 0.00008). Additionally, easements that contained remnant forest habitat had significantly greater species richness (F= 8.671, p = 0.005) and diversity (F= 5.521, p = 0.02) than those lacking remnant forest. We observed slight positive relationships between percent canopy cover and both avian species richness and diversity. Our results suggest the importance of well-developed, forested communities to increasing bird species use of restored BLH forests in the MAV. Providing data on the response of biotic communities to WRP restoration can aid in guiding future restoration efforts to ensure that project goals are met.

  • Influence of Elevation on Canada Warbler Population Dynamics in the Central Appalachian Mountains*
  • Stephanie H. Augustine; Christopher T. Rota
    Canada Warblers (Cardellina canadensis) are a Nearctic-Neotropical migratory songbird that has exhibited apparent declines in abundance over recent decades. This species occupies a wide range of environmental conditions throughout their range but lack substantial data regarding elements driving variation in demography and the strength of population migratory connectivity. The aim of this research is to (1) determine the relationship between demography and environmental conditions along an elevation gradient and (2) ascertain migratory route and wintering locations of a population of Canada Warblers breeding in the central Appalachian Mountains. Our research takes place at six study sites spanning an approximate 130km north-south gradient within the Monongahela National Forest, West Virginia, ranging in elevation from 526-1282m. We will estimate apparent survival with a three-year mark recapture study; in 2019 we marked 104 birds, which we will re-sight in 2020 and 2021. Beginning in 2020, we will assess reproductive success by monitoring nests using game cameras. We will model survival and reproductive rates as a function of elevation and additional environmental variables, which will elucidate the region-specific habitat-demography relationship. To determine migration strategies, we will deploy 33 adult male Canada Warblers with light-level geolocator tags in spring 2020 and retrieve tags from returned individuals in spring 2021. This study is the first we know of to track individual Canada Warblers throughout the year and will establish a baseline for full annual cycle modeling in the future. This presentation will include results from the first two field seasons of the project.

  • Testing the Adaptive Significance of Song in Willow Flycatcher Subspecies
  • Sarah Gonzalez; Sean Mahoney
    In birds, song is an important characteristic that allows birds to recognize members of their own species. How differences in song characteristics arise and how they are maintained remain important questions in evolutionary ecology. Song may be shaped by the need to acquire mates (sexual selection), or by factors that affect survival of the individual (natural selection). In both cases, different environments may lead to different song characteristics. The Acoustic Adaptation Hypothesis (AAH) predicts that animals should optimize their signal given their environmental context. Under this hypothesis, higher frequency songs with shorter internote intervals (i.e. trills) should transmit more efficiently in open and more humid habitats because of reduced heat loss and overlapping sound waves. Individuals in a population that can optimize song transmission in their environment should have higher reproductive success and be able to pass those song traits onto their offspring. In the US, Willow Flycatchers (Empidonax traillii) occur across a broad ecological gradient and four subspecies are currently recognized. Previous studies have found differences in song but no study has assessed the adaptive significance of song variation within this group. We tested the AAH in Willow Flycatchers by relating song characteristics from 134 recordings including frequency and internote intervals to vegetation canopy cover and climate variables from the PRISM climate database. We found general support for the AAH: Although vegetation density was non-linearly related to song frequency and trills, we found a strong linear relationship between song characteristics and climate variables. Higher frequency songs with more trills were found in mesic areas and lower frequency songs with fewer trills were found in xeric areas. Our findings suggest that the Willow Flycatcher’s song is shaped by the climatic conditions at the site which may indicate that populations of Willow flycatchers occupying different habitats are diverging evolutionarily.

  • An Evaluation of Avian Use of Marsh Terraces in Gulf Coastal Wetlands*
  • Madelyn McFarland; Brian Davis; Michael Brasher; Mark Woodrey; Larry Reynolds; Fernando Vizcarra
    Louisiana’s coastal wetlands support millions of resident and migratory birds annually. However, Louisiana has experienced 90% of the total decline of coastal wetlands within the continental United States, accounting for most loss among all Gulf Coastal wetlands. Marsh terracing is one method used to combat coastal wetland loss. The restoration technique uses in situ sediment to construct segmented ridges in open water areas of coastal wetlands. An objective of marsh terracing is to improve marsh conditions and habitat for a diversity of species. Despite terraces being an increasingly useful component of coastal restoration efforts, previous research on their value as waterbird habitat is limited in spatial and temporal scale. Using both on-the-ground point count surveys and fixed-wing aerial surveys, our study evaluates avian use of marsh terraces across multiple paired sites (terraced and non-terraced) in coastal Louisiana. Avian monitoring efforts focus on two primary guilds of birds, breeding secretive marsh birds and wintering waterfowl. Results from the first field season indicate that: 1) terraced sites were used predominately by non-focal species such as red-winged blackbirds, 2) there was low use of terraced sites by focal species such as rails, 3) and there was generally low use of both terraced and non-terraced sites by wintering waterfowl, although species abundances varied in space and time. Field efforts are ongoing, and data collection will be completed by July 2020. Future analysis will examine relationship between avian use and habitat characteristics of study sties (e.g., submerged aquatic vegetation, diversity, and structure of emergent vegetation).

  • Evaluation of NRCS Cover Crop Practices as Avian Wintering, Stopover, and Nesting Habitat in Tennessee*
  • Brittany Panos
    The U.S. Department of Agriculture Natural Resources Conservation Service administers the winter cover crop program to provide financial incentives to agricultural producers to sow herbaceous plant seeds to protect agricultural fields from soil erosion during the non-growing season (late fall through spring). Landowner/producer sign-up for this program has increased to over 200,000 ha in 2019 in Tennessee. Although benefits related to soil retention and water quality improvements have been documented, potential benefits related to avian wildlife use remain largely unknown. We are providing an in-depth examination of the use of cover crop fields by birds during the stationary non-breeding period, during migration, and during the breeding season.. We are comparing the use of cover crop fields with no-till row-crop fields without cover crops. We selected a set of 80 fields with cover crops and 20 control fields without cover crops for evaluation across two counties in middle and two counties in western Tennessee. Avian use is monitored along two 100-m line transects in each field in a distance sampling framework every three weeks during the January-June sampling period. Supplemental drive netting with mist nets and banding is used to further quantify avian use. We are nest-searching during the breeding season for focal grassland species to document the role these fields may play in supporting breeding activity. Results and preliminary conclusions from the first field season will be summarized and presented.

  • True Metabolizable Energy of Targeted and Unfavorable Seed Species in Waterfowl Management*
  • Matthew R. Williams; Heath M. Hagy; Joseph D. Lancaster; Joshua M. Osborn; Aaron P. Yetter; Auriel M.V. Fournier; Christopher N. Jacques
    True Metabolizable Energy (TME) is a measure of the assimilable energy (kcal) a food item provides a consumer and can be useful for wildlife managers to decide which plants to encourage/discourage when managing wetlands for waterfowl. The current availability of TME estimates limit the understanding of the impacts habitat management decisions have on the energetic carrying capacity of wetlands. Furthermore, TME values for specific food taxa may differ among waterfowl species and such differences are important for determining appropriate management strategies. Prior TME research prioritized food items most commonly found in waterfowl diets and mostly focused on a single waterfowl species, leaving a gap in information on moist-soil seeds considered undesirable or invasive by wetland managers. Therefore, we will estimate TME values of several moist-soil seeds considered by waterfowl managers as desirable (e.g. Polygonum lapathifolium, Cyperus erythrorhizos and Leptochloa panicoides) and several considered to be undesirable (e.g., Sesbania herbacea, Polygonum hydropiperoides, Sida spinosa) within wild-caught mallard (Anas platyrhynchos), northern pintail (A. acuta), green-winged teal (A. crecca) and blue-winged teal (Spatula discors). From December 2019 to March 2020, we completed 7 feeding trials using 4 seed and 3 duck species during the non-breeding period. Each 48-hour trial included 24 hours of fasting to clear the birds’ digestive tracts, precision feeding a known mass of a single food item, followed by a 24-hour period of excreta collection. Individual ducks were used in multiple trials with different seed species but were given a >14-day respite between trials. Our results will be used to support conservation planning models to refine waterfowl objectives stepped down from the North American Waterfowl Management Plan to better inform waterfowl conservation planners and wetland managers throughout the Mississippi Flyway of the United States.

  • Mallard Body Condition and Duck Energy Days: Are They Related*
  • John T. Veon; Brett A. DeGregorio; David G. Krementz
    Long-distance migrations exert enormous stresses upon wildlife. Individuals attempting such feats without adequate resources may not survive. North American waterfowl face the unique challenge of needing to maintain their body mass during an environmentally difficult time. We are currently analyzing body mass trends in relation to land management from mallards sampled throughout the Lower Mississippi Valley of Arkansas over the next two duck seasons (2019-2020 and 2020-2021). I am working with hunters, hunting clubs, and plucking stations to sample hunter-killed mallards. For each bird, I measure the wing length (mm) using an ornithological ruler, measure the body mass using a digital scale, and sex and age the birds by observing morphological features in plumage. I plan to calculate a Body Condition Index (BCI) by using the residuals from a mass by wing length linear regression. Because previous research suggests that mallards forage up to 30 km in one day, I will use GIS to delineate a circular buffer with a 30 km radius around where each mallard was harvested and calculate the proportion of each buffer comprised of land managed for waterfowl, natural areas, and anthropogenically modified land. I will use a multiple regression analysis to explore correlations between mallard body mass and BCI with various land cover proportions. We hypothesize that mallards harvested within or near waterfowl management areas will have a higher BCI than those harvested far from managed land. Although field collection is currently underway, I plan to present the findings from the 2019-2020 Arkansas duck season.

  • Interior Population Trumpeter Swan Migration Ecology and Conservation*
  • David W. Wolfson; Randall Knapik; John Fieberg; David Andersen
    Interior Population (IP) trumpeter swans (Cygnus buccinator) currently breed throughout most of the western Great Lakes region and have recently increased dramatically in abundance and distribution following multiple reintroduction efforts starting in the 1960s. However, beyond rough estimates of population trends and distribution, there is relatively little recent information about their ecology, migratory patterns, and genetic structure, hindering conservation decision-making. To address current information needs, we are marking trumpeter swans with GPS-GSM transmitters to evaluate annual movement and habitat-selection patterns, migration pathways, and whether individuals perform molt migrations. We are also collecting blood samples from all captured swans to quantify lead concentrations in swans across the IP breeding range and perform genomic analyses using ddRAD-seq, a high throughput sequencing technique. We banded 19 adult trumpeter swans in Minnesota (n = 7) and Michigan (n = 12) during the summer of 2019 and plan to deploy another 86 GPS-GSM collars during 2020 in Minnesota, Michigan, Wisconsin, Iowa, Ohio, and Manitoba. Visualizations of collared swan movements and annual reports are available at https://trumpeterswan.netlify.com/. Our project will help guide management of trumpeter swans throughout the IP by providing information about migration, year-round movements, and habitat selection while using blood to evaluate potential sub-lethal effects of lead ingestion, measure genetic diversity, gene flow, and genetic differentiation from source populations to reintroduced trumpeter swans within the IP.

  • The Effects of Prescribed Fire in Gulf of Mexico Marshes: on Mottled Ducks and Black and Yellow Rails
  • Auriel M.V. Fournier; Chris Butler; Warren Conway; Robert J. Cooper; Jim Cox; Nicholas Enwright; Kristine Evans; Erik I. Johnson; James Lyons; J. Andrew Nyman; Robert Rohli; Mark Woodrey
    High marsh is a unique habitat type, imminently threatened by sea-level rise and characterized by a community of specialized emergent vegetation that tolerates irregular tidal inundation, as well as being the habitat of several birds of high conservation concern. Although extensive work has been devoted to understanding the role of fire in maintaining ecosystem functions in upland systems, little has been done on coastal wetlands or the response of birds to fire in high marsh wetlands. Without an understanding of how prescribed fire impacts high marsh ecosystems, including several high priority bird species within these ecosystems, natural resource managers are limited in their ability to manage and conserve the biodiversity of the Gulf Coast. Black rail, yellow rail, and mottled duck are birds of conservation concern for many organizations, including all five Gulf Coast states, the Gulf Coast Joint Venture, and the National Audubon Society. Collectively, models of occurrence, distribution, and abundance of these three species will enable assessments of their degree of sympatry and potential trade-offs or synergies from prescribed fire applications. We will monitor the avian response to prescribed fire applications in an adaptive management framework, where we will make predictions, monitor the avian response and use that new information to improve our models and our next set of predictions. Collectively, our research will allow us to reduce key uncertainties about the application of prescribed fire in high marsh across the northern Gulf of Mexico.

  • Environmental and Anthropgenic Drivers of Mallard Resource Selection during the Non-Breeding Period*
  • Nicholas M. Masto; Abby Blake-Bradshaw; Cory Highway; Jamie C. Feddersen; Heath M. Hagy; Dan L. Combs; Bradley S. Cohen
    Effective conservation of highly mobile species requires understanding the exogenous and endogenous factors governing habitat selection at multiple spatiotemporal scales. For waterfowl, much research has focused on habitat requirements on the breeding grounds. Holistic approaches have more recently come to vogue wherein migratory and winter habitats also are recognized as important components to waterfowl survival, reproduction, and recruitment (i.e., cross-seasonal effects). However, these life-history stages and their potential influence on population dynamics remain understudied. Further, waterfowl encounter stressful environmental and anthropogenic conditions during non-breeding periods which may alter behavioral patterns and subsequent fitness. Thus, quantifying variation in movement, spatiotemporal resource selection, and other factors mediating these behaviors during non-breeding periods will inform managers of behavioral trade-offs made by waterfowl and optimal management strategies during vulnerable periods of their annual cycle. New GPS tracking technology allows researchers to monitor avian movement at great spatial extents which should provide more complete portrayals of life-history strategies during non-breeding periods (i.e., autumn-spring migration). Thus, we will 1) compare winter and migration strategies of mallards (Anas platyrhynchos) within and among years using GPS-GSM solar rechargeable transmitters (n = 360) and 2) investigate their decision-making relative to energetic, environmental, and anthropogenic covariates across non-breeding periods. During the first year of our study, we deployed 120 transmitters between November 2019-January 2020. Mallards used state and federal waterfowl sanctuaries extensively during winter. Currently, 65% of individuals have begun migration with average departure on 14 March 2020. In general, stopover duration was short and concentrated within the Upper Mississippi River floodplain and Illinois River Valley. We will quantify movements, range sizes, and resource selection during migration and assess regional and site-specific philopatric behavior. We expect results to provide a thorough depiction of non-breeding mallard ecology at spatial scales relevant to resource management agencies.

  • Quantifying Great Egret Habitat Selection to Inform Shellfish Aquaculture Placement
  • Scott Jennings; Nils Warnock; David Lumpkin; T. Emiko Condeso
    Where commercial activities like food production occur on publicly owned land and water, the agencies administering those areas must weigh economic benefits against potential negative impacts to wildlife and other natural resources. These management decisions can be improved with better understanding of how and when wildlife species use these areas, and the degree to which the commercial activity in question does or does not preclude wildlife also using the area. In Tomales Bay, CA, shellfish aquaculture harvest has grown nearly five-fold since 1990, and requests to increase the footprint of these operations are pending. Current aquaculture leases overlap with intertidal and shallow subtidal habitats that are important foraging habitat for a range of wading birds. We tracked 10 Great Egrets (Ardea alba) with GPS telemetry between 2017-2019. We used integrated step selection analysis to evaluate Great Egret selection for eelgrass beds, inter- and subtidal areas covered by existing aquaculture infrastructure, and other inter- and subtidal areas. There was considerable variation in habitat selection between individuals. Tidal marsh and tidal flat were generally selected for more strongly than subtidal habitats. Most egrets selected for eelgrass beds. There was some evidence for selection of aquaculture areas, but egrets appeared to use these areas less than adjacent habitats outside the footprint of the aquaculture infrastructure. We discuss how placement of new aquaculture facilities on Tomales Bay can minimize impacts on egrets.

  • Methods for Evaluating Ecosystem Services Provided by Birds on Kenyan Coffee Farms*
  • Bailee R. Romaker
    Birds, Beans, and Bugs! This research project just finished its third and final field season in Kenyan coffee plantations. Birds were mist netted and captured to collect measurements and fecal samples. Our goal is to analyze the DNA of the fecal samples to see what insects the birds are consuming. We want to see if the birds are performing ecosystem services to the coffee and the coffee farmers through consuming pest insects. Birds are cheaper than pesticides and better for the environment, therefore, managing for birds might be a win-win for the managers and the ecosystem. I would like to present the methods of preparing and conducting field work, along with the process of PCR analysis that we are preparing to do once fecal samples return to the states.

  • Differential Timing of Migrating Northern Saw-Whet Owls Based on Age and Sex Groups*
  • Carter Freymiller; Michaela Meehl; Mandie Lang; Madison Fell; Cole Suckow
    The Northern saw-whet owl (Aegolius acadicus) (NSWO) is a mesopredator within upland ecosystems. NSWO’s migrate in fall from September until December, peaking around mid-October, and this species is relatively abundant in central Wisconsin during this time. Previous studies have found that juvenile diurnal birds of prey migrated significantly earlier than adults. This is due to adults attempting to remain on breeding territories for as long as possible, therefore delaying fall migration. We are interested in whether this trend also applies to nocturnal birds of prey. We hypothesized that we would see hatch-year birds migrate earlier in the season than adults and male birds migrate later than their female counterparts. This project is conducted in the fall, with mist nets, at Sandhill Wildlife Area, Wood Co., WI. We used all viable data from the duration of the project and performed 2-sample independent t-tests for the mean day of migration on each of the age & sex groups, as well as the hatch-year vs. adults and Male vs. Female sub data sets. We found a significant difference in these two groups, demonstrating that adult birds are likely to migrate earlier than hatch-year birds. The data demonstrating the difference in migration time in males vs. females showed us that males were likely to migrate earlier than females. Finally, we observed the same trend of adult birds migrating earlier than juvenile birds in the subset of female birds only.

  • Mallard Response to a Gradient of Experimental Disturbance on Waterfowl Refuges during Winter*
  • Abigail G. Blake-Bradshaw; Nicholas M. Masto; Cory J. Highway; Daniel L. Combs; Jamie C. Feddersen; Heath M. Hagy; Bradley S. Cohen
    Winter is an energetically and physically stressful time for animals and may be especially demanding for hunted species such as waterfowl. Waterfowl refuges are important management tools which provide forage and sanctuary for waterfowl during winter. Refuges are essential because anthropogenic disturbance from recreational activities may displace waterfowl from preferred foraging areas, reduce daily foraging time, and modify diurnal behavior. Waterfowl increase refuge use during hunting periods likely due to limited disturbance and provision of food resources. However, increased refuge use may result in pressure from the public and other stakeholders to offer access to refuges for hunting or other activities (e.g., birding, photography). Despite seasonal closures of refuges to the public, empirical evidence quantifying waterfowl responses to a gradient of disturbance regimes and subsequent implications on individual fitness is lacking and may have greater population-level consequences than is currently understood. To determine the impact of disturbance on waterfowl movements, space use, and site fidelity, we will assess mallard (Anas platyrhynchos) responses to a gradient of experimentally induced disturbance on state and federal refuges in west Tennessee. During winter 2019-2020, we captured 120 mallards on refuges and fitted them with GPS/GSM solar rechargeable transmitters. We simulated distinct disturbance treatments which represent activities that potentially occur on waterfowl refuges including 1) waterfowl surveys from a vehicle, 2) bird watching while walking, and 3) hunting in planted corn or wooded areas. We will assess mallard behaviors before and after experiencing disturbance. Specifically, we will examine shifts in mallard resource selection and determine whether changes in selection are associated with survival. This research will provide insight into direct and indirect effects of disturbance on wintering waterfowl and further inform acceptable levels of disturbance for state and federal refuges to better meet the needs of waterfowl and people.

     

    Poster
    Location: Virtual Date: Time: -