AUTHORS: Ryley C. Harris, Virginia Tech; Karen Powers, Radford University; Dorothy McKenzie Clore, Radford University; Georgia Davidson, Radford University.
ABSTRACT: Bird-window collisions (BWCs) constitute a significant source of mortality for both resident and migratory birds. Because windows reflect surrounding landscape components such as vegetation or sky, birds do not always perceive glass as a barrier. Here we demonstrate a novel technique to classify and quantify reflections in windows on the Radford University campus in southwest Virginia, U.S.A. We deployed a consumer-grade Unmanned Aerial Vehicle, i.e., drone, to photograph 14 contiguous or near-contiguous window columns across five campus buildings in August 2020. For each study aspect, the drone (equipped with an RGB camera) captured images at ca. 5-meter altitudinal increments from the ground floor to the roof of each building (3-6 images/vertical column). We then manually classified each image in ImageJ to calculate approximate proportions of reflected (1) vegetation, (2) sky, (3) and other buildings, plus (4) non-reflective glass. We used a generalized linear model to determine how proportional reflections of vegetation, sky, buildings, and non-reflective glass varied across vertical increments. We found that the proportion of sky significantly decreased with increasing photo heights, whereas proportion of nonreflective glass significantly increased with increasing heights. This supports previous findings that because birds are drawn to sky reflections, they may collide at relatively lower positions on buildings. Inconsistency in landscape design and building positioning on the campus precluded trends in vegetative or building reflections by height. Our pilot study demonstrates the applicability of a consumer-grade drone for investigating visual characteristics of reflections that influence BWCs from variable observation angles. We suggest the expanded use of drone images as a straightforward technique to measure changes in reflection characteristics from varying degrees of observation. They are a novel method in developing a BWC risk assessment as well as potential mitigation strategies in a suburban or
TAGS: avian mortality; bird-window collision; drone
AUTHORS: Christopher Wozniak, Radford University; Sierra Felty, Radford University; Karen Powers, Radford University
ABSTRACT: Allegheny woodrats (Neotoma magister) are karst-specializing rodents that are threatened, endangered, or otherwise in conservation need in many states within their range. Major threats include habitat loss and fragmentation, and raccoon roundworm endoparasites. Ectoparasites (here, limited to fleas, ticks, and bot flies) are poorly studied in this species. Previous studies have been geographically-limited to West Virginia, Tennessee, and Indiana, the latter, from >35 y ago. Contemporary collections from Virginia, Ohio, and Indiana woodrats may collectively provide a better understanding of host specificity. Expected donations on-going surveys from additional states will help us expand the survey range-wide. Ectoparasite identifications are being carried out via morphological features and DNA from species added to the Barcode of Life Database. Results to be presented in light of ongoing identification efforts.
TAGS: woodrat ectoparasite survey
AUTHORS: Justin McLaughlin, Dr. Karen Powers, Dr. Robert Sheehy
ABSTRACT: Window collisions are a leading cause of mortality in birds. Although many carcasses can be identified by distinct morphological features, others are less obvious due to scavenging by predators, decay, or plumage uncertainty due to bird age or season. At Radford University, we are using DNA barcoding to identify these questionable birds. This DNA barcoding is a continuation of an initial project at Radford University, and has proven to be a useful tool. In fall, 2020, we used DNA to confidently identify 12 individual birds that were collected in 2020. Of the 12, 2 did not match our original identifications. Two of the confirmed species were new species additions to our project. Twenty-two additional samples currently are in progress, and additional results will be presented in light of these analyses. The use of DNA barcoding in bird species identification is an on-going project and a valuable component in this bird-window collision study on campus.
TAGS: DNA barcoding, Bird-window collisions, Birds
AUTHORS: Philip W. Kavouriaris, Murray State University; Andrea K. Darracq, Murray State University; Matthew J. Springer, University of Kentucky
ABSTRACT: Current research on scavenger communities and food web dynamics has demonstrated the effects of carrion size, seasonality, and landcover type on scavenger community composition and carrion use. However, few studies have investigated the interactions between these factors. Here we provide preliminary findings of two carrion trials conducted in western Kentucky, one beginning in October 2020 and the other in March 2021. To measure scavenger diversity, we collected road killed mammalian carcasses, placed them on public lands, and monitored each carcass passively with a trail camera. To test the influence of carrion size, seasonality, and landcover type on scavenger community composition, carrion was classified as either small or large, carrion sites were designated as one of two landcover types (open or wooded), and trials were conducted in both the fall and spring seasons. Over 90,000 pictures were collected from 26 total carrion sites monitored over the course of these trials. Analysis of these trials is ongoing and further trials will be conducted beginning in fall 2021.
TAGS: scavenger, ecology, Kentucky
AUTHORS: Justine L. Smith, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia and The Jones Center at Ichauway, Newton, Georgia, USA; Kelsey Hoskins, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia and Tall Timbers Research Station, Tallahassee, Florida, USA; Faith Kruis, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia and The Jones Center at Ichauway, Newton, Georgia, USA; Kim Sash, Tall Timbers Research Station, Tallahassee, Florida, USA; L. Mike Conner, Jones Center at Ichauway, Newton, Georgia, USA; Michael T. Mengak, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia USA
ABSTRACT: Wild pigs (Sus scrofa) were introduced into the southeastern United States by Spanish settlers in the 1500s. Subsequent escape from enclosures and illegal transportation of pigs caused a northward and westward range expansion that today creates natural resource losses exceeding $3.8 billion/year in crop and timber damage and costs associated with pig removal efforts. The goal of this project is to assess the efficacy of pig reduction methods and the response of natural resources to pig removals conducted by USDA APHIS Wildlife Services in accordance with the National Feral Swine Damage Management Program. Our work occurs in southwestern Georgia and northern Florida on private properties ranging in size from 1,500 to 7,000 acres with varying land management practices and prior histories of wild pig management activities. We initiated camera trapping during summer and fall 2020 and GPS tracking of pigs during spring 2021. We also conducted vegetation surveys and water sampling around camera trap locations. Data will be used to monitor wild pig populations during reduction efforts, to quantify impacts of fecal contamination in water bodies, to assess evidence for intraspecific competition, to measure changes in native vegetation, and to document co-occurrence of native fauna. Results will be used in evaluating effects of wild pig removal on natural resources and associated economic benefits.
AUTHORS: Brittany Hansey, Auburn University; William Gulsby, Auburn University; Robert Gitzen, Auburn University
ABSTRACT: State agencies must navigate the trade-off between maximizing hunter opportunity (i.e., number of hunting days and areas open to hunting), ensuring a quality hunting experience (i.e., number of animals seen and harvested), and providing wildlife habitat. The severity of this trade-off depends partly on the degree to which hunter disturbance affects waterfowl use of hunted lands. We are implementing a study in the Tennessee River Valley (TRV) in north Alabama with the objective of quantifying the effects of hunting pressure on waterfowl relative abundance on state management units in the TRV. Surveys incorporate units with varying hunting regulations (i.e. hunted 4 vs. 7 days/week), and refuges (unhunted). During our first field season in winter 2020-2021, we developed and implemented a UAV survey protocol for assessing waterfowl numbers on survey units much larger than most published UAV waterfowl studies. We conducted surveys before/during the hunting season and point counts during/after the hunting season. Drone surveys detected 1.60 ducks/ha before and 1.84 ducks/ha during the hunting season on unhunted areas, compared to 0 ducks/ha before and 0.08 ducks/ha during the hunting season on hunted areas. Similarly, point counts during the season detected 11.06 ducks/ha on unhunted units compared to 0.12 ducks/ha on hunted units. This difference decreased after the season (0.54 ducks/ha unhunted; 0.30 ducks/ha hunted units). These results are consistent with our prediction that waterfowl relative abundance would be greater on unhunted units during the season, but increase on hunted units after the hunting season. However, initial results are not consistent with our prediction that we would detect higher densities of waterfowl on hunted units before the season versus during the season, likely due to timing of migration. Reductions in hunter opportunity on the hunted areas we surveyed may be required to increase hunter satisfaction and waterfowl use of those areas.
TAGS: Waterfowl hunting disturbance
AUTHORS: J. Taylor Gibson, Department of Wildlife, Fisheries & Aquaculture, Mississippi State University; Hunter Mentges, Department of Wildlife, Fisheries & Aquaculture, Mississippi State University; Ishab Poudel, Department of Poultry Science, Mississippi State University; Pratima Acharya Adhikari, Department of Poultry Science, Mississippi State University; J. Brian Davis, Department of Wildlife, Fisheries & Aquaculture, Mississippi State University
ABSTRACT: Wood ducks (Aix sponsa), hooded mergansers (Lophodytes cucullatus), and black-bellied whistling ducks (Dendrocygna autumnalis) are sympatric secondary cavity-nesting duck species in the southeastern United States. Interspecific clutches are common, eggs accumulate in nests from parasitic laying, and strife between females may occur, potentially subjecting eggs to breakage. Understanding the durability of eggs of these species is important for explaining variation in nest and egg hatching success. Our prediction was that eggshell breaking strength (EBS) of hooded merganser eggs would be the greatest among the three species. We collected a total of 67 fresh eggs of the species from nest boxes at two sites in Mississippi in spring-summer 2021. We measured eggshell strength using an Instron Universal Testing Machine (Model 3345; Instron Inc., Norwood, MA) and eggshell thickness using a micrometer (Ames, IA). We measured EBS (Newtons) at the equators of all eggs. We used Tukey’s pairwise comparison to test for differences in eggshell strength among species. Mean EBS differed among all species (P < 0.0001) and was greatest in hooded merganser, followed by black-bellied whistling duck and wood duck. The EBS was 120.05 (SD = 12.03, n = 7) for hooded merganser, 52.44 (SD =10.04, n=30) for black-bellied whistling duck, and 32.95 (SD =3.90, n = 30) for wood duck. Eggs of hooded merganser had the highest EBS, likely attributed to greater eggshell thickness among these species. Our results are preliminary, and further analyses will explore if eggshell strength correlates inversely with egg breakage in our study.
TAGS: cavity-nesting ducks, eggshell strength, Mississippi
AUTHORS: Sierra Felty, Radford University; Chris Wozniak, Radford University; Karen Powers, Radford University; Rick Reynolds, Department of Wildlife Resources; Wil Orndorff, Department of Conservation and Recreation, Natural Heritage Program; Mark Ford, US Geological Survey
ABSTRACT: Following the onset of White-nose Syndrome (WNS) in Virginia, little brown bats (Myotis lucifugus) have decreased by an estimated 99% in hibernaculum counts. We sought to document if little brown bats were changing the timing of reproductive stages between pre- (1992-2009; from multiple locations and sources) and post-WNS-onset (2012-2021, focused only on 3 known maternity colonies that remain in Virginia). Since 2012, maternity colonies were visited once in late May, during gestation, and once in mid-July, when young are volant. Data collection focused on trends in female reproductive status (pregnant, lactating, post-lactating) across Julian date and body mass index scores. Analyses through summer 2019 suggested no significant changes in little brown bats’ reproductive trends since the on-set of WNS. We know that WNS is negatively impacting little brown bat populations, but this impact is not evident in the survivors’ reproductive strategies. Although COVID prevented 2020 surveys, ongoing 2021 surveys will be included in our analyses, and trends will be presented in light of these updated analyses.
TAGS: little brown bats
AUTHORS: Bailey N Zagrabelny; Eddy Wild; Michael J Shaughnessy Jr., – Department of Natural Sciences, Northeastern State University, Tahlequah, OK
ABSTRACT: We examined centrarchid and percid assemblages before and after a time of seasonal temperature change to better understand the effects of temperature variation on spatial distribution of naturally occurring centrarchid and percid populations in northeastern Oklahoma streams. Cold season data collected during winter were compared to warm season data collected during the summer of 2020. Fish were collected at Echota Public Access and at Town Branch Creek both of which are located in Cherokee county, Oklahoma. Fish specimens were collected using a Smith-Root Inc. LR-24 Electrofisher electroshocking backpack, seine, block and dip nets. Centrarchid and percid total length were measured and recorded along with species, location, and numbers. Three pools and three riffles at each site over the warm and cold season periods were sampled. Chi-square statistical analyses were used to analyze the data to determine significance. We rejected the null hypotheses stating that there were no differences in centrarchid and percid habitat selection between seasons. Chi-square contingency table analyses demonstrated an interaction between season and habitat for percids but not for centrarchids indicating that percid habitat selection is influenced by seasonal changes. Understanding of the effects of environmental abiotic factors on fish distributions and behavior as they change seasonally is key to successful population management. Knowledge of how centrarchids and percids use their habitats and how their seasonal habitats shift throughout the year will aid in the identification of critical stream habitats for these economically and ecologically important fish.
TAGS: behavior, thermoregulation, distribution
AUTHORS: Connor D. Cunningham, Missouri State University; Hae H. Kim, Missouri State University; Quinton E. Phelps, Missouri State University; Clint Hale, Missouri Department of Conservation ; Shane Bush Missouri, Department of Conservation ; Andy Turner, Missouri Department of Conservation ; Jeff Koppelman, Missouri Department of Conservation; Mike Siepker, Missouri Department of Conservation
ABSTRACT: Trout are a commonly stocked fish and used to supplement and create new fisheries. Missouri Department of Conservation has recently started stocking triploid brown trout (Salmo trutta) in Lake Taneycomo. Triploid fish are sterile and may exhibit faster growth rates than diploid fish. These factors can be useful tools that allow managers to better meet management goals. Anglers began to catch large triploid brown trout in Lake Taneycomo which eventually led to the capture of two state records in 2019. The latter of which was just shy of a new world record. These notable catches have attracted public attention to Lake Taneycomo and the surrounding area (i.e., Branson). Lake Taneycomo attracts a large number of anglers to the area, and is an important economic driver. Triploid brown trout stocking may increase the recruitment, retention, reactivation, and satisfaction of anglers and therefore should be considered in future management plans.
TAGS: Triploid, Brown Trout, Angler satisfaction
AUTHORS: Dylan Bakner, Louisiana State University; Kevin Ringelman, Louisiana State University
ABSTRACT: To promote nest success, managers of wood ducks (Aix sponsa) place artificial nest structures (hereafter, nest boxes) on the landscape to provide additional nest sites. Often, nest boxes are equipped with predator guards to exclude species such as raccoons (Procyon lotor) and snakes (Serpentes spp). Over the last 30 years, Louisiana Department of Wildlife and Fisheries (LDWF) has maintained ~2,000 nest boxes for wood ducks. Currently, LDWF and Louisiana State University are evaluating the state’s nest box program. From February 4 – July 28, 2020, 428 wood duck nests were monitored from 314 nest boxes located in central Louisiana. Of those nests, 231 (54.0%) failed and 197 (46.0%) were successful. However, successful nests were subjected to partial depredation events, and the loss of ≥1 egg was observed in 41.1% of successful nests. Determining the predators responsible for partial clutch loss could help managers identify new methods to excluded nest predators. Here, we monitored wood duck nests using trail cameras to 1) identify the predator community, 2) determine when partial clutch loss is most likely to occur, and 3) determine clutch characteristics associated with successful nests. From April 6 – June 24, 2021, we placed trail cameras inside nest boxes, providing 24-hr surveillance of each nest. Cameras were set to take 10-second videos when motion was detected, allowing for a 1-second delay between videos. Cameras captured 116,005 video files from 50 nests. We documented 82 partial clutch loss events from nests equipped with cameras. Currently, videos are being processed to identify the predators responsible for these losses. Initial observations suggest red-bellied woodpeckers (Melanerpes carolinus) are the most common nest predator, which has never been formally documented. Video analysis is ongoing to determine other nest predators, when partial clutch loss commonly occurs, and clutch characteristics that promote nest success.
TAGS: wood ducks, partial clutch loss, nest predators
AUTHORS: Mikayla Thistle, Clemson University; Jamie Dozier, South Carolina Department of Natural Resources; Mark McAlister, South Carolina Department of Natural Resources; Beth Ross, US Fish and Wildlife Service
ABSTRACT: Through much of its range, Bachman’s Sparrow (Peucaea aestivalis) uses the wiregrass (Aristida spp.) 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 instead are dominated by bluestem grasses (Schizachyrium spp. and Andropogon spp.), bracken fern (Pteridium aquilinum), and shrubs. Habitat use of Bachman’s Sparrow in this 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 study was 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, Santee Coastal Reserve, and Washo Reserve, South Carolina to inform best management practices for Bachman’s Sparrow. We conducted repeated visit point count surveys at 95 locations and used open N-mixture models to estimate the effects of habitat management and forest stand characteristics (e.g. prescribed burns, basal area, stem density) on Bachman’s Sparrow abundance, apparent survival probability, and recruitment rates during the 2020 and 2021 breeding seasons. We also located nests to identify vegetation composition and structure characteristics that Bachman’s Sparrows select for nest-sites. To determine if habitat selection in our study population was adaptive, we monitored nests and related nest-site selection to nest survival rates by comparing habitat characteristics related to selection with those related to survival. Bachman’s Sparrows selected nest-sites that had intermediate grass cover compared to available nest-sites; however, nest survival rates showed no clear relationship to any measured covariates. The results of this study can be used to inform region-specific management plans and restoration of degraded habitats, which often lack typical understory species like wiregrass, to increase Bachman’s Sparrow abundance and reproductive success.
TAGS: habitat selection, habitat management, ornithology
AUTHORS: Bryce Blake, Roanoke College; Rachel Collins, Roanoke College
ABSTRACT: Wildlife that can adapt to human-dominated landscapes are increasing in abundance in suburban landscapes, which results in increased wildlife-human conflict and negative habitat impact. Understanding how wildlife use rural and suburban landscapes differently can help us mitigate the risk of contention with animal habitat. We compared the frequency of habitat use of a suburban forest fragment with rural forests in the Roanoke Valley, Virginia. Camera traps were used to assess trap success rate, number of detections, and latency of the first detection in different seasons. We found that although white-tailed deer had the highest detections in both habitats, detections and trap success was significantly higher in the suburban forest fragment compared to rural forests. We suggest that white-tailed deer are not more abundant nor have smaller ranges, but rather that they use core habitats more intensely in suburban landscapes. For mesopredators, trap success was high for raccoons and cats compared to other mesopredators in the suburban forest fragment compared to the rural forest which had higher detections for more mesopredator species. These results indicate that suburban forest fragments and the surrounding suburban matrix supports fewer mesopredators than rural forests. Taken together, the concentration of white-tailed deer and mesopredators in and around suburban forest fragments is potentially correlated to higher levels of damage to vegetation and wildlife-human conflict.
TAGS: white-tailed deer, mesopredators, suburban restoration
AUTHORS: Jennifer Moran, Florida Fish and Wildlife Conservation Commission, Kevin Johnson, Florida Fish and Wildlife Conservation Commission, John Saxton, Florida Fish and Wildlife Conservation Commission, Kirk Dunn, Florida Fish and Wildlife Conservation Commission, Chelsea Buescher, Florida Fish and Wildlife Conservation Commission, Kyle Miller, Florida Fish and Wildlife Conservation Commission, Sam Burke, Florida Fish and Wildlife Conservation Commission
ABSTRACT: Florida’s subtropical climate and shallow lakes allow for aquatic vegetation to thrive. The proper data to aid in making informed aquatic plant management decisions for these lakes is a necessity. Standardized vegetation mapping was added to the Florida Fish and Wildlife Conservation Commission’s (FWC) Long Term Monitoring Program in 2015 to monitor the state’s aquatic habitat and to help inform management decisions. Mapping occurs annually on lakes across Florida during the peak growing season and provides important data such as submersed vegetation percent area covered (PAC), percent volume of water infested (PVI), species richness, density, and frequency of occurrence estimates for all vegetation species encountered. Submersed vegetation mapping is conducted by a boat-mounted sonar unit and transducer to record 200 kHz down-looking broadband sonar imagery, while samples at point intercepts are collected to determine vegetation speciation along a survey grid. Grid dimensions are a function of lake size and preferred data resolution. Sonar data are processed and merged using BioBase, a third-party company, which provides whole lake estimates and maps of submersed vegetation PAC, PVI, bathymetry contours, and bottom hardness. The point-intercept data are used to create plant assemblage and species-specific maps. Between 2015 and 2020, 113 lakes were mapped of which 18% have occurred annually. Many of these lakes are mapped for cooperative projects within FWC and other agencies. These data can be used as a baseline data set of habitat conditions that are monitored through time, inform current or future research and management actions, and could help explain changes to fish and wildlife populations.
TAGS: submersed vegetation, monitoring, sonar mapping
AUTHORS: Jacob Shurba, Clemson University James C. Kennedy Waterfowl and Wetlands Conservation Center; Richard Kaminski, Clemson University James C. Kennedy Waterfowl and Wetlands Conservation Center; Kristi Whitehead, Clemson University Dept. of Biological Sciences; Beau Bauer, Nemours Wildlife Foundation; Kyle Barrett, Clemson University Dept. of Forestry and Environmental Conservation; Beth Ross, U.S. Fish and Wildlife Service; Greg Yarrow, Clemson University Dept. of Forestry and Environmental Conservation
ABSTRACT: Few studies have tested if wood duck nest and egg hatching success are affected by microbial colonies in nest boxes, and none has examined a possible linkage to recruitment (i.e., return of yearling females to nest boxes). Additionally, the use of boxes by multiple hens annually may increase bacteria, parasites, and other potential pathogens that could decrease egg hatchability. While incubation is a natural selective deterrent for microbial infection of the eggs and developing embryos, the period before incubation may risk infection of eggs. During the 2020-2021 nesting seasons, we collected 300 sterile swabs of eggs in nest boxes in Florida and Georgia to examine microbial growth on eggs. We will describe the field and laboratory methods for this novel study and preliminary results, including those from an experiment to test if different wood shavings reduce microbial infections of eggs and increase hatching success.
TAGS: Wood Duck, Bacteria, Nest Boxes
AUTHORS: Stephanie A. Braswell, Auburn University School of Forestry and Wildlife Sciences; William D. Gulsby, Auburn University School of Forestry and Wildlife Sciences; Robert A. Gitzen, Auburn University School of Forestry and Wildlife Sciences; Joshua M. Osborne, Illinois Natural History Survey, Forbes Biological Station, Bellrose Waterfowl Research Center, University of Illinois at Urbana-Champaign; Heath M. Hagy, US Fish and Wildlife Service
ABSTRACT: Gadwall (Mareca strepera) rank second among hunter-harvested duck species in the Mississippi Flyway and Alabama; however, scarce data exist regarding the movement ecology and survival rates of gadwall during the non-breeding period. We used GPS and VHF telemetry to examine aspects of movement ecology and survival rates of gadwall in the Tennessee River Valley of northern Alabama during the non-breeding period. During November-February 2017-2019, we outfitted gadwall with GSM satellite (2017-2018) or VHF (2018-2019) transmitters (n = 51), and obtained diurnal and nocturnal locations. Using locations and land cover data, we estimated 95% home range and 50% core area sizes, mean daily movement distances, resource selection, and survival. Core area size was greater on public lands (14,297 ha) than on private lands (4,975 ha) and refuges (5,083 ha). Overall, core area composition averaged 50.7% private lands, 45.3% refuges, and 4% hunted public land. Home ranges exhibited similar trends to core areas in size and composition. Emergent herbaceous wetlands were selected over all other cover types during both day and night, with woody wetlands and open water being the second most selected cover types, depending on diel period. Mean daily movement distances were low compared to other Southeastern studies, averaging 1,207-1,415m. Survival analysis using the Kaplan-Meier estimator and Cox Proportional Hazard models include 47 individuals and 17 confirmed deaths. None of the covariates (sex, age class, body condition, capture site, year, and proportion of locations on refuge lands vs. other ownerships) examined had detectable effects on the risk of mortality; the overall estimated survival rate with a 95% confidence limit from Dec. 1 to March 1 was 0.38 (0.24, 0.61). Our results indicate that disturbance may be a factor limiting gadwall use of hunted public lands, and highlight the role of private lands in waterfowl conservation efforts in the region.
TAGS: Gadwall, Movement Ecology, Survival
AUTHORS: Hannah Schley, University of Delaware; Christopher Williams, University of Delaware; Josh Homyack, Maryland Department of Natural Resources; Bill Harvey, Maryland Department of Natural Resources; Alicia Berlin, United States Geological Survey
ABSTRACT: Wildlife biologists have observed yearly variation in wintering lesser scaup (Aythya affinis) group dynamics and habitat use in the Chesapeake Bay. Some years the wintering populations show larger flocks in the open bay while other years show smaller and more uniformly distributed groups in surrounding tributaries. These shifts may be linked to variation in environmental (e.g. temperature and water quality) and/or food abundance. Understanding variables that affect scaup distribution have implications for habitat and harvest management. In the winters of 2020-2023, we will be using both behavioral observations and telemetry to understand habitat use, group size, and behavioral energy expenditures to understand these patterns. First, over three years, we will conduct behavioral scan samples at set locations across the Chesapeake Bay to understand how behavioral energy expenditure and group size interactions are impacted by habitat type/location and environmental variations. Second, during the winters of 2021-22 and 2022-23, we will implant internal GPS transmitters in lesser scaup (n=50) at Eastern Neck National Wildlife Refuge located on the Chester River. GPS locations will be analyzed to understand daily movement patterns, behaviors, and habitat selection as a function of time and environmental variation. Last, we will analyze historic food preference and clam spatial availability to identify potential temporal changes to the benthic layers in the open bay and tributaries.
TAGS: Waterfowl, Winter Habitat Use, Energetics
AUTHORS: Katie E. Miranda, LSU School of Renewable Natural Resources; Dylan L. Bakner, LSU School of Renewable Natural Resources; Kevin M. Ringelman, LSU School of Renewable Natural Resources
ABSTRACT: Traditional waterfowl recruitment studies either mark flightless juveniles with leg bands or tag newly hatched ducklings prior to leaving the nest with metal tags affixed to the webbing of the foot (hereafter, web tag). However, there are persistent concerns that web tags may be lost because they are embedded in soft tissue that can easily tear, and so there is a need for a more reliable marker. Passive integrated transponder (PIT) tags are implanted under the skin above the dorsal vertebrae and between the humerus bones and can be read using a handheld radio frequency identification (RFID) scanner. From March to July 2020, 525 wood duck ducklings were marked with web tags and 581 were marked with PIT tags to compare the recovery rate for each tag type. The following season from February – July 2021, we recovered 10 PIT-tagged and 10 web-tagged ducklings as incubating hens, providing preliminary information that retention rates for both tag types are similar, and yield an apparent recruitment of 3.6%. Results from this first year of recapture data suggest that both methods are equally reliable, and their relative merits will vary based on the research question at hand. Hunters are able to identify and report web tags from harvested birds, but PIT tags require specialized equipment to read and are unlikely to be reported. However, PIT tags are more useful in behavioral studies where stationary readers placed around cavity entrances can be used to quantify visitation rates with minimal disturbance.
TAGS: Mark-recapture, tag retention, PIT tag
AUTHORS: Mikayla Call, Virginia Tech Department of Fish and Wildlife Conservation; Dr. Sarah Karpanty, Virginia Tech Department of Fish and Wildlife Conservation; Alexandra Wilke, The Nature Conservancy in Virginia, Volgenau Virginia Coast Reserve; Zak Poulton, The Nature Conservancy in Virginia, Volgenau Virginia Coast Reserve; Ruth Boettcher, Virginia Department of Wildlife Resources; Dr. James Fraser, Virginia Tech Department of Fish and Wildlife Conservation; Dr. Dan Catlin, Virginia Tech Department of Fish and Wildlife Conservation
ABSTRACT: Metompkin Island is a hotspot for breeding American Oystercatchers (Haematopus palliatus), supporting over 100 pairs annually. Productivity rates have declined, averaging 0.34 ± 0.08 (Mean ± SE) fledged chicks/pair from 2016–2020 compared to 0.73 ± 0.08 from 2002–2015. This decline triggered the need to re-evaluate the local drivers of American Oystercatcher reproductive success. Field- and camera-based monitoring at nest and brood-rearing sites indicated that productivity is primarily lost during the brood-rearing stage; however, the threats driving this decline in chick survival are unknown. Monitoring to identify these threats can be difficult because chicks are often challenging to relocate after hatching and signs indicating sources of chick mortality are ephemeral, especially when monitoring intervals are >1 week in length. We monitored the reproductive success of approximately 30 pairs of American Oystercatchers on Metompkin Island during the 2021 breeding season. To monitor chick survival, we used a combination of radio telemetry and direct observation of broods. We attached radio transmitters to one chick per brood and tracked them until death or fledging. Radio telemetry improved our chances of relocating chicks after they left the nest site, allowing for more accurate estimates of chick survival and the opportunity to identify sources of mortality from remains of radio-tagged chicks. We located chick remains in active and abandoned Atlantic ghost crab (Ocypode quadrata) burrows, though it is unclear if crabs were acting as predators or scavengers. Observations of aggression by adult American Oystercatchers towards chicks from nearby broods, including one observation of an adult killing a chick from a neighboring brood, indicate that density-dependent factors could be limiting chick survival on Metompkin Island. Finally, radio telemetry allowed us to confirm one case of chick movement outside of their known brood territory, caused by either brood territory swapping or chick swapping between two pairs.
TAGS: Shorebirds, reproductive monitoring, radio telemetry
AUTHORS: Emma Fehlker Campbell; John B. Hewlett; Andrea K. Darracq; Department of Biological Sciences, Murray State University
ABSTRACT: Chronically raised stress levels correlate with decreased immune function in vertebrates and could lead to increased susceptibility to parasites. Specifically, helminth endoparasites and hemoparasites are frequently found in wild snake populations but little is known about their physiological effects. The objective of our study was to assess the individual and interactive effects of helminth endoparasites and hemoparasites on cottonmouth physiological stress. We used two measures of stress; corticosterone (CORT), which is a primary stress hormone excreted by cottonmouths, and heterophil to lymphocyte (H:L) ratios, which generally correlate with CORT levels and are representative of longer-term stress. We collected 33 cottonmouths (> 300 g) from three populations in Western Kentucky. Within 3 – 5 minutes of capture we collected blood from the caudal vein of each snake to quantify baseline CORT, H:L ratios, and hemoparasite presence. We determined helminth presence by counting parasites in the oral lining of each snake. Analyses of these data are ongoing, and we will present preliminary results.
TAGS: Herpetology, Parasitism, Stress ecology
AUTHORS: Justine L. Smith, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia USA; L. Mike Conner, The Jones Center at Ichauway, Newton, Georgia, USA; Michael T. Mengak, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia USA; Roger C. Lowe, Warnell School of Forestry & Natural Resources, University of Georgia, Athens, Georgia USA
ABSTRACT: Wild pigs (Sus scrofa) have been translocated legally and illegally for hunting purposes. Illegal relocations of wild pigs aided in their northern and westward range expansion. Originally introduced in the 1500s by Spanish settlers, populations of wild pigs are now found in at least 35 states with an estimated population surpassing 6 million animals. Costs associated with wild pigs for removal and crop and timber damage exceed USD $3.8 billion annually. The objectives of this study are to (1) observe changes in wild pig damage to crops as pig reduction methods are implemented by USDA APHIS Wildlife Services under the guidance of the National Feral Swine Damage Management Program and (2) compare unmanned aerial system (UAS) sampling methods across four field types experiencing wild pig damage. We began UAS sampling in May 2021. We selected 14 fields for sampling, including 4 corn (Zea mays), 3 peanut (Arachis hypogaea), 5 cotton (Gossypium spp.) and 2 mixed corn/peanut fields. Sampling methods included flights to 15 random waypoints, flying random transects, and conducting 2 circular flights per field. The exterior circular flight was flown at the radius plus 12m to capture the edge; the interior circular flight at half the radius plus 6m. All flights were flown at an elevation of 70m followed by on-the-ground measurements. Data will be used to assess impact of pig removal efforts on crop damages, estimate economic loss attributed to wild pigs, and determine an efficient sampling method for quantifying wildlife damage in fields.
AUTHORS: Savannah L. Lancaster, Rebecca Salen, Karen E. Powers, Radford University
ABSTRACT: A common cause of avian death, especially during fall migration, is collisions with windows, as the surrounding environment reflects nearly seamlessly off of the glass. Previous research has yet to reach a consensus that naive migrants (i.e., young-of-the-year individuals) are more likely to collide with windows in unfamiliar environments. We sought to examine trends during summer and early fall months in which juveniles are volant and identifiable through feather color, patterns, and wear, as well as other discernible morphological features. To date, we have aged American robins, northern cardinals, and European starlings, and will continue aging efforts in August and September with Swainson’s thrushes and multiple species of warblers salvaged from recorded window collisions. Results will be presented in light of these aging efforts. We emphasize the value of aging techniques and such data utility in short- and long-term efforts to reduce bird-window collisions on our college campus.
TAGS: bird-window collisions
AUTHORS: Ashley K. Tunstall, Louisiana State University; Catrina V. Terry, Great Plains Regional Office, Ducks Unlimited; Kevin M. Ringelman, Louisiana State University
ABSTRACT: The Prairie Pothole Region of North and South Dakota provides brood rearing habitat for a variety of waterfowl species, most of which migrate to the southern United States during winter. Waterfowl broods particularly rely on invertebrates to survive during early weeks of development. The abundance and species composition of invertebrates in the region may be influenced by ephemeral abiotic factors that are difficult to evaluate, especially variation in daily weather. Using weather data downloaded from The National Oceanic and Atmospheric Administration (NOAA) and invertebrate samples from prairie wetlands collected from surface activity traps in the summers of 2019 and 2020, we attempted to diagnose the effects of weather conditions on total invertebrate abundance. We log-transformed total invertebrate abundance and used regression to diagnose effects of maximum and minimum temperature, average daily wind speed, and percent lunar illumination. We found no relationship between invertebrate abundance and any of the weather conditions we modeled (confidence intervals for all coefficients bounded zero). However, our invertebrate samples were collected over a relatively short time period to achieve objectives of a related study, so the corresponding weather data may not have been variable enough to drive differences in invertebrate abundance. Improved experimental design would be necessary to improve external and internal validity. Nevertheless, knowing that modest summer variation in weather does not impact prairie wetland invertebrate abundance has important implications for understanding the daily forage availability of ducklings that later make their way to the southern states in fall and winter.
TAGS: Invertebrates, Weather, Waterfowl
AUTHORS: Da'Vaun Lee, Roanoke College; Sofia Falkengren, Roanoke College; Rachel Collins, Roanoke College
ABSTRACT: Increasingly, residents near degraded natural areas in suburban landscapes are interested in restoration to decrease invasive species and increase native diversity. Such restoration has important benefits for residents’ quality of life and for ecosystems function. We applied mosaic-landscape concept to a ten-acre degraded natural area in Salem, Virginia that is slated for restoration work in order to understand patterns of wildlife habitat use in the area. Specifically, we assessed the diversity and abundance of birds, small mammals, and salamanders in three distinct habitats (landfill, wetland, forest fragment) prior to restoration management. The landfill holds construction rubble and not municipal waste. The 30-40-year-old forests represents succession from a residential yard. The wetland is a low-lying swale that drains athletic fields and lawns. We also conducted vegetation surveys to assess habitat quality. The vegetation surveys showed that all habitats are highly invaded with non-native species. Non-woody vegetation was highest in the wetland and low in the landfill and forest. Contrary to expectations, of the 27-bird species identified, species richness was lowest in the forest and highest in the landfill. No salamanders were detected suggesting that the area is too degraded/isolated to support them. Not surprisingly small mammals were trapped in the forest and wetland but not the landfill. Taken together our findings are inline with a mosaic-landscape model that different habitat types support different wildlife communities. These results indicate that restoration focused on the reduction of invasive and increase in native plant species will likely coincide with increases in wildlife species diversity including species of conservation concerns.
TAGS: Non-game wildlife, suburban restoration, Habitat use
AUTHORS: Jessica McNulty. University of Delaware; Hannah Schley, University of Delaware; Christopher Williams, University of Delaware; Josh Homyack, Maryland Department of Natural Resources; Shawn Sullivan, Delaware Department of Natural Resources and Environmental Control; Delaware Wild Lands, LLC
ABSTRACT: Wood ducks (Aix spinosa) are a waterfowl species with a long history of conservation and management concern in the United States. A collaborative project across the Atlantic and Mississippi Flyways began in 2019 investigating geographic differences in wood duck box selection and nest success. The furthest northern area of the project includes 7 study sites between Maryland and Delaware. Currently, there is limited research comparing wood duck nest box use and success between macrohabitat types located within local regions. Between Maryland and Delaware, habitat systems range from open wetlands to forested wetlands, historically used by nesting wood ducks. Through March - July 2021, we monitored nest boxes (n=301) between 7 sites in Delaware and Maryland. We collected macro- and microhabitat measurements throughout the 2021 nesting season that will be used to analyze habitat selection of nesting wood ducks. We will present results that compare the effects of macrohabitat (e.g. wooded habitat vs open marsh) and microhabitat (e.g. visual obscurity, canopy coverage) between the Maryland and Delaware sites to identify a relationship between nest box use and success to habitat types. Our findings from this study will be used for further wood duck research and management for nest box placement to improve wood duck populations in the Mid-Atlantic region.
TAGS: Wood Duck, Habitat types
AUTHORS: Trey E. Johnson, Texas Tech University; Bradley Kubecka, Tall Timbers Research Station; C. Brad Dabbert, Texas Tech University
ABSTRACT: Northern bobwhite (Colinus virginianus; bobwhite) once occupied a large portion of the Pineywoods ecoregion of Texas. After decades of land use changes and fire suppression, habitat has become fragmented and bobwhite have all but been extirpated from the region. During 2020, we initiated habitat restoration on a private property in Polk County, TX, USA with a goal of restoring 3,440 ha of bobwhite habitat. Initial timber volume was 21.9 m2 / ha in May 2021. Timber thinning is ongoing and expected to be complete by December 2023; target basal area is 9 m2 / ha. Our objectives are to document bobwhite response over time using a robust design occupancy model with a before-after-control-impact approach to evaluate habitat and management factors associated with occupancy, colonization, and extirpation. We completed surveys (n = 98) for the first primary session during 15 May – 15 June 2021 at 14 sites to document initial occupancy; no bobwhite were detected during surveys. Translocation will be used to restore the northern bobwhite population to this fragmented landscape because bobwhite have not responded to habitat management efforts. The results from this study will be used to inform future northern bobwhite restoration efforts in the Pineywoods ecoregion of Texas.
TAGS: habitat, translocation, quail
AUTHORS: Emily Miller, Cindy Von Haugg, and Richard Kaminski, Clemson University’s James C. Kennedy Waterfowl & Wetlands Conservation Center; and Beau Bauer, Nemours Wildlife Foundation
ABSTRACT: The wood duck (Aix sponsa) is recognized as the state duck of South Carolina. It comprised ~40% of the total duck harvest in the state and generally ranked second or third among ducks harvested in the Mississippi and Atlantic flyways. We are conducting a regional study of recruitment of female wood ducks nesting in boxes in 8 states in the Atlantic and Mississippi flyways, including South Carolina where we have monitored 182 boxes managed by South Carolina Department of Natural Resources at Lake Moultrie (33.3054° N, 79.9579° W). Use of nest boxes by female wood ducks generally was >80% during 2019-2021. This great use of boxes by wood ducks also attracted black rat snakes (Pantherophis alleghaniensis) to boxes, which depredated eggs and hens and were the greatest cause of nest failures during the study. Snakes depredated 376 wood duck eggs. We conducted an experiment to deter rat snakes from nest boxes. We removed emergent and woody vegetation in a ~2 m radius around boxes and affixed a sock containing commercially available snake repellent pellets to nest boxes. Additionally, we tagged rat snakes captured in boxes with a passive integrated transponder (PIT) to uniquely identify snakes if subsequently recaptured. We PIT tagged 78 snakes in 2020-2021, followed by 85 recaptures across both years. Recapture frequencies for a single individual varied between 1-3 events; 16 individuals marked in 2020 were recaptured in 2021. Mean length of captured snakes was 144 cm (± SE = 2.61), suggesting minor variation in length of captured snakes (CV ≤ 2%) and that snakes were relatively large to surmount predator guards and gain access to nest boxes. We will present preliminary results of the snake deterrence experiment and discuss a new snake relocation experiment that may be more effective than our deterrence efforts.
TAGS: wood duck, nest boxes, snakes