Scholarly Works, Conservation Management Institute

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Characterization of golden-cheeked warbler Dendroica chrysoparia habitat at Fort Hood, Texas, USA
Emrick, Verl III (2019-05-26)
The golden-cheeked warbler Dendroica chrysoparia is a federally endangered, neotropical-nearctic migrant songbird that breeds in central Texas, USA, and prefers mature, closed canopy oak–Ashe juniper woodlands for nesting and foraging. Fort Hood is an 87 890 ha military reservation located in central Texas in Bell and Coryell Counties on the eastern edge of the Edwards Plateau ecoregion. We surveyed for golden-cheeked warblers and measured habitat variables at 95 separate locations in a 56.6 km2 research area that supports a golden-cheeked warbler breeding population. We detected golden-cheeked warblers on 34 of 95 (36%) point count locations. Principal component analysis was used to reduce the 27 habitat variables to a set of uncorrelated variables. This analysis resulted in the identification of 4 principal components that accounted for 52% of the variance. Logistic regression identified one principal component (ratio of Ashe juniper to other woody species) that was strongly related to golden-cheeked warbler occurrence. Our data indicate that a 4:1 ratio of Ashe juniper to other woody species is an important feature of occupied golden cheeked warbler habitat, particularly in the mid- to upper canopy at Fort Hood.
Climate characteristics of the Big Levels region, Augusta County, Virginia
Klopfer, Scott D. (Virginia Natural History Society, 1999)
A Comparison of Systematic Quadrat and Capture-Mark-Recapture Sampling Designs for Assessing Freshwater Mussel Populations
Carey, Caitlin; Jones, Jess W.; Butler, Robert S.; Kelly, Marcella J.; Hallerman, Eric M. (MDPI, 2019-08-07)
Our study objective was to compare the relative effectiveness and efficiency of quadrat and capture-mark-recapture (CMR) sampling designs for monitoring mussels. We collected data on a recently reintroduced population of federally endangered Epioblasma capsaeformis and two nonlisted, naturally occurring species—Actinonaias pectorosa and Medionidus conradicus—in the Upper Clinch River, Virginia, over two years using systematic quadrat and CMR sampling. Both sampling approaches produced similar estimates of abundance; however, precision of estimates varied between approaches, years, and among species, and further, quadrat sampling efficiency of mussels detectable on the substrate surface varied among species. CMR modeling revealed that capture probabilities for all three study species varied by time and were positively associated with shell length, that E. capsaeformis detection was influenced by sex, and that year-to-year apparent survival was high (>96%) for reintroduced E. capsaeformis. We recommend that monitoring projects use systematic quadrat sampling when the objective is to estimate and detect trends in abundance for species of moderate to high densities (>0.2/m²), whereas a CMR component should be incorporated when objectives include assessing reintroduced populations, obtaining reliable estimates of survival and recruitment, or producing unbiased population estimates for species of low to moderate densities (≤0.2/m²).
Drought but not population density influences dietary niche breadth in white-tailed deer in a semiarid environment
Folks, Donald J.; Gann, Kory; Fulbright, Timothy E.; Hewitt, David G.; DeYoung, Charles A.; Wester, David B.; Echols, Kim N.; Draeger, Don A. (Ecological Society of America, 2014-12)
A premise in ungulate foraging theory is that animals become less selective and expand the breadth of their dietary niche as the availability of palatable forage declines with increasing herbivore population density or drought. Increased niche variation resulting from intraspecific competition is thought to create less similar diet composition and decreased diet overlap between individuals within a population at higher densities than between individuals within less dense populations. These ideas were largely developed in relatively mesic environments and their applicability to ungulate foraging in semiarid environments is unclear. We tested the idea that white-tailed deer (Odocoileus virginianus) contract dietary niche breadth; reduce dietary plant species diversity, richness, and evenness; and become more individualistic in forage choices in response to a fourfold difference in population density (12 deer/km(2) versus 50 deer/km(2)) in semiarid shrubland in Texas, USA. We used the bite count method to determine diet composition of tame female white-tailed deer seasonally during summer 2009 to spring 2011. We were able to determine impacts of drought on foraging dynamics a posteriori because sampling during each season fortuitously occurred under both drought and non-drought conditions. Population density did not affect diet richness, diversity, breadth, evenness, overlap, and similarity. Diet richness, diversity, breadth, and evenness tended to be greater in non-drought conditions. For white-tailed deer, the idea that dietary niches expand in response to increasing population density is not robust across environments. In semiarid environments, variation in precipitation has a much stronger influence on dietary niche breath and intraspecific diet overlap of deer than population density does.
Landscape Characteristics Related to Use of Artificial Roosts by Northern Long-eared Bats in North-central West Virginia
De La Cruz, Jesse L.; Ward, Ryan L.; Schroder, Eric S. (Humboldt Field Research Institute, 2018-09-01)
In the eastern US, research is needed on the establishment and evaluation of conservation measures for forest-dwelling bats, in general, and for the newly listed Myotis septentrionalis (Northern Long-Eared Bat), in particular. Our objectives were to evaluate the overall use of 3 artificial roosting structures-rocket box, nursery box, and artificial bark-by bats and to relate this use to local landscape characteristics in north-central West Virginia. We monitored 306 structures during summer 2016 and detected use (i.e., presence of guano, visual identification, capture of bats) at 132 (43%) roosts, of which 55 (42%) were confirmed, through capture or visual identification, to contain Northern Long-eared Bats. Nursery boxes were used more than expected based on availability (60%), but rocket boxes accounted for 40 (73%) of the roosts confirmed to be occupied by Northern Long-eared Bats, with 70% being used by maternity colonies of this species. We utilized binomial generalized linear models and an information theoretic approach to examine use of artificial roosts by maternity colonies of Northern Long-eared Bats. Our best-supported model differentiating structures occupied by maternity colonies from those that housed individual bats showed relationships to elevation, slope, area solar radiation, and distance to streams and large (>200 ha) forests. Our study provides initial guidance for land and wildlife managers on implementing an effective conservation and management technique for bats within this region.
Monitoring Nontimber Forest Products Using Forest Inventory Data: An Example with Slippery Elm Bark
Kauffman, Jobriath S.; Prisley, Stephen P.; Chamberlain, James L. (2017-07)
The USDA Forest Service Forest Inventory and Analysis (FIA) program collects data on a wealth of variables related to trees in forests. Some of these trees produce nontimber forest products (NTFPs) (e.g., fruit, bark, and sap) that are harvested for culinary, decorative, building, and medicinal purposes. At least 11 tree species inventoried by FIA are valued for their bark. For example, slippery elm (Ulmus rubra Muhl.) is included in FIA forest inventories, and the bark is used for its medicinal value. Despite widespread use of NTFPs, little quantitative information about abundance, distribution, and harvest is available to support sustainable management. Methods for using the FIA database to monitor and explain the situation regarding selected NTFPs are presented. The focus is on using FIA data to assess for (1) geographic distribution, (2) abundance, (3) applicable metrics (e.g., square feet of bark), and (4) change over time.
Post-white-nose syndrome passive acoustic sampling effort for determining bat species occupancy within the mid-Atlantic region
Deeley, Sabrina M.; Kalen, Nicholas J.; Freeze, Samuel R.; Barr, Elaine L.; Ford, W. Mark (2021-06)
We assessed the sampling effort requirements for detecting the presence of extant bat species following the impact of white-nose syndrome in the mid-Atlantic region of the United States. We acoustically sampled 27,796 nights across 846 sites between 15 May and 15 August 2016-2018 within the District of Columbia, Maryland, Pennsylvania, Virginia, and West Virginia. We developed simulations to determine the number of sites required to document bat species when each site was sampled different numbers of nights. We examined these simulations with respect to land cover, physiographic region, and time period. We generally found that sampling a greater number of sample sites within a survey area increased detection more than increasing the number of nights at individual sampling sites. The sampling effort required to detect a given bat species varied by species, as well as land-cover type and physiographic region. Our results suggest that land managers and researchers should use caution in using protocols developed with other objectives, e.g., the U.S. Fish and Wildlife Service endangered and threatened bat species and the North American Bat monitoring programs? methods are designed relative to their specific needs. Unfortunately, neither protocol may be adequate for accurately detecting bat communities within all mid-Atlantic areas.
A Range-Wide Meta-Analysis of Wild Turkey Nesting Phenology and Spring Season Opening Dates
Whitaker, Darroch M.; Pack, James C.; Norman, Gary W.; Stauffer, Dean F.; Klopfer, Scott D. (Michigan Department of Natural Resources, 2005)
Timing of nesting is an important consideration when setting opening dates for spring male-only wild turkey (Meleagris gallopavo) hunts. We conducted a meta-analysis in which we used mean dates of incubation initiation from 58 studies to evaluate a priori models hypothesized to predict turkey nesting phenology across the species’ range. Models were based on geographic setting, climate, and management activities, and had weak to moderate explanatory power (Range R2 adj = 0.12–0.55). We developed 2 post hoc models to better predict mean incubation date, and used one of these to generate a range-wide map predicting timing of nest incubation. A second model selection exercise focused solely on the eastern subspecies of wild turkey, and our best model of incubation date included population status and a cubic term for latitude (n =41, R2 adj = 0.80). Lastly, we compared incubation initiation dates to opening dates for spring male-only hunting in each jurisdiction. Of 34 states and provinces for which we obtained data, 25 opened spring hunting 2 weeks prior to the mean date of incubation initiation, and 18 of these also allowed fall either-sex hunting. This finding is noteworthy because extended fall seasons and spring hunting during the pre-nesting period can lead to additive and unsustainable levels of female kill.
Summer-Habitat Suitability Modeling of Myotis sodalis (Indiana Bat) in the Eastern Mountains of West Virginia
De La Cruz, Jesse L.; Ward, Ryan L. (Humboldt Field Research Institute, 2016-03)
Little information exists with regard to suitable summer habitat of Myotis sodalis (Indiana Bat) in West Virginia. Our research objectives were to use ultrasonic acoustic equipment and automated identification software to collect presence data for Indiana Bats and to examine habitat characteristics and availability across the local landscape. We used a maximum entropy (MAXENT) approach to determine if the distribution of various ecological factors such as landuse/landcover, forest fragmentation, aspect, area solar radiation, slope, proximity to permanent water, and elevation influenced foraging-habitat suitability of Indiana Bats. We sampled across the 1160-ha Camp Dawson Collective Training Area in Preston County, WV, to determine Indiana Bat presence. We employed the collected presence data to examine habitat suitability within a 16,151-ha study area encompassing the training facility. Based on MAXENT results, we characterized highly suitable Indiana Bat habitat as including large tracts of contiguous forest cover (>200 ha) associated with low to modest slopes (<20°), road corridors, and areas of high solar radiation (>5.5 x 105 WH/m2). High (81–100%) and medium-high (61–80%) suitability classes were uncommon across the landscape (0.6% and 2.7%, respectively), with the broad medium-to-high suitability classes (41–100%) collectively comprising only 11.4% of the study area. Elevation (m) and aspect contributed little to the model and displayed low permutation importance that did not vary notably from the corresponding percent contribution. These variables, along with close proximity to permanent water (≤200 m away), are likely not limiting ecological factors. The results of this study supplement current knowledge of summer habitat of the Indiana Bat and provide land and wildlife managers localized guidance on conservation priorities within the region.
Terrestrial Wildlife in the Post-mined Appalachian Landscape: Status and Opportunities
Lituma, Christopher M.; Cox, John J.; Spear, Stephen F.; Edwards, John W.; De La Cruz, Jesse L.; Muller, Lisa I.; Ford, W. Mark (Springer, 2021)
Coal mining is an anthropogenic stressor that has impacted terrestrial and semi-aquatic wildlife in the Appalachian Plateau since European settlement. Creation of grassland and early-successional habitats resulting from mining in a forested landscape has resulted in novel, non-analog habitat conditions. Depending on the taxa, the extent of mining on the landscape, and reclamation practices, effects have ranged across a gradient of negative to positive. Forest-obligate species such as woodland salamanders and forest-interior birds or those that depend on aquatic systems in their life cycle have been most impacted. Others, such as grassland and early-successional bird species have responded favorably. Some bat species, as an unintended consequence, use legacy deep mines as winter hibernacula in a region with limited karst geology. Recolonization of impacted wildlife often depends on life strategies and species’ vagility, but also on altered or arrested successional processes on the post-surface mine landscape. Many wildlife species will benefit from Forest Reclamation Approach practices going forward. In the future, managers will be faced with decisions about reforestation versus maintaining open habitats depending on the conservation need of species. Lastly, the post-mined landscape currently is the focal point for a regional effort to restore elk (Cervus canadensis) in the Appalachians.
Winter roost selection of Lasiurine tree bats in a pyric landscape
Jorge, Marcelo H.; Ford, W. Mark; Sweeten, Sara E.; Freeze, Samuel R.; True, Michael C.; St Germain, Michael J.; Taylor, Hila; Gorman, Katherine M.; Garrison, Elina P.; Cherry, Michael J. (2021-02-09)
Day-roost selection by Lasiurine tree bats during winter and their response to dormant season fires is unknown in the southeastern United States where dormant season burning is widely applied. Although fires historically were predominantly growing season, they now occur in the dormant season in this part of the Coastal Plain to support a myriad of stewardship activities, including habitat management for game species. To examine the response of bats to landscape condition and the application of prescribed fire, in the winter of 2019, we mist-netted and affixed radio-transmitters to 16 Lasiurine bats, primarily Seminole bats (Lasiurus seminolus) at Camp Blanding Joint Training Center in northern Florida. We then located day-roost sites to describe roost attributes. For five Seminole bats, one eastern red bat (Lasiurus borealis), and one hoary bat (Lasiurus cinereus), we applied prescribed burns in the roost area to observe bat response in real-time. Generally, Seminole bats selected day-roosts in mesic forest stands with high mean fire return intervals. At the roost tree scale, Seminole day-roosts tended to be larger, taller and in higher canopy dominance classes than surrounding trees. Seminole bats roosted in longleaf (Pinus palustris), slash (Pinus elliotii) and loblolly pine (Pinus taeda) more than expected based on availability, whereas sweetbay (Magnolia virginiana), water oak (Quercus nigra) and turkey oak (Quercus laevis), were roosted in less than expected based on availability. Of the seven roosts subjected to prescribed burns, only one male Seminole bat and one male eastern red bat evacuated during or immediately following burning. In both cases, these bats had day-roosted at heights lower than the majority of other day-roosts observed during our study. Our results suggest Seminole bats choose winter day-roosts that both maximize solar exposure and minimize risks associated with fire. Nonetheless, because selected day-roosts largely were fire-dependent or tolerant tree species, application of fire does need to periodically occur to promote recruitment and retention of suitable roost sites.
Year-round monitoring reveals prevalence of fatal bird-window collisions at the Virginia Tech Corporate Research Center
Schneider, Rebecca; Barton, Christine M.; Zirkle, Keith W.; Greene, Caitlin F.; Newman, Kara B. (PeerJ, 2018-04-04)
Collisions with glass are a serious threat to avian life and are estimated to kill hundreds of millions of birds per year in the United States. We monitored 22 buildings at the Virginia Tech Corporate Research Center (VTCRC) in Blacksburg, Virginia, for collision fatalities from October 2013 through May 2015 and explored possible effects exerted by glass area and surrounding land cover on avian mortality. We documented 240 individuals representing 55 identifiable species that died due to collisions with windows at the VTCRC. The relative risk of fatal collisions at all buildings over the study period were estimated using a Bayesian hierarchical zero-inflated Poisson model adjusting for percentage of tree and lawn cover within 50 m of buildings, as well as for glass area. We found significant relationships between fatalities and surrounding lawn area (relative risk: 0.96, 95% credible interval: 0.93, 0.98) as well as glass area on buildings (RR: 1.30, 95% CI [1.05-1.65]). The model also found a moderately significant relationship between fatal collisions and the percent land cover of ornamental trees surrounding buildings (RR = 1.02, 95% CI [1.00-1.05]). Every building surveyed had at least one recorded collision death. Our findings indicate that birds collide with VTCRC windows during the summer breeding season in addition to spring and fall migration. The Ruby-throated Hummingbird (Archilochus colubris) was the most common window collision species and accounted for 10% of deaths. Though research has identified various correlates with fatal bird-window collisions, such studies rarely culminate in mitigation. We hope our study brings attention, and ultimately action, to address this significant threat to birds at the VTCRC and elsewhere.

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