Steven B. Castleberry

Movements of allegheny woodrats in relation to timber harvesting

The Allegheny woodrat (Neotoma magister) occurs in the Appalachian Mountains, forming colonies in rock outcrops, cliffs, and caves. Populations on the northern and western peripheries of the range have experienced drastic declines in the past 20-30 years. Dependence upon rock outcrops makes Allegheny woodrats vulnerable to land-use practices that alter habitats surrounding colonies. To examine the impacts of timber harvesting on Allegheny woodrat behavior, we radiotracked 37 adults during summer 1998 and 1999 in clearcut, diameter-limit, and intact forest stands in the central Appalachians of West Virginia. Home range size and foraging movements generally,were greatest at diameter-limit sites and smallest in intact forests in 1998, following a poor mast crop. We detected no differences among harvest methods in 1999 when mast was abundant. We believe that when hard mast was scarce, woodrats increased foraging movements and home range size to locate mast or sufficient alternative foods. Additionally, woodrats used clearcut and adjacent forested areas in proportion to availability. Our results suggested that clearcutting has minimal impact on woodrat movements, home range, and habitat use if sufficient intact forest is retained adjacent to colonies. Harvesting methods that selectively remove important mast-producing species may represent the greatest disturbance to Allegheny woodrats from forest management.

EFFECTS OF PRESCRIBED FIRE ON HERPETOFAUNA IN BOTTOMLAND HARDWOOD FORESTS

Abstract Abundance, diversity, and richness of herpetofaunal species were compared between burned and unburned bottomland hardwood stands at Di-Lane Plantation Wildlife Management Area (WMA) in Burke County, Georgia, from July to October 2001. Two trap clusters, each consisting of a drift fence pitfall array, four coverboards, and three polyvinyl chloride (PVC) pipe refugia, were randomly placed within each of three burned and three unburned stands. Habitat variables were measured within a 0.04-ha circular plot centered on each trap cluster. A total of 346 individuals, representing 21 species, was captured in 348 array nights. Amphibian abundance, diversity, and richness were similar between burned and unburned stands. Reptile abundance and diversity were greater in burned stands, whereas reptile species richness was similar between burned and unburned stands. Winter burns did not significantly affect coarse woody debris volumes between burned and unburned stands and may have accounted for similar amphibian abundance, diversity, and richness. Greater reptile abundance and diversity in burned stands likely was a result of decreased ground cover providing greater thermoregulatory opportunities.

Multi-Scale Roost-Site Selection by Evening Bats on Pine-Dominated Landscapes in Southwest Georgia

Abstract Bats likely incorporate multi-scale criteria when selecting roost sites, which may change across different landscapes. During summers 2002 and 2003, we used radiotelemetry to investigate day-roost selection of evening bats (Nycticeius humeralis) at multiple scales in mature longleaf (Pinus palustris; natural) and intensively managed loblolly pine (P. taeda; managed) landscapes in the Gulf Coastal Plain of Georgia, USA. We used Akaikes Information Criterion (AIC) to evaluate models describing roost-site selection at the tree, plot, stand, and landscape scales. Evening bats on the natural site selected day-roosts based on tree, plot, and landscape characteristics, but bats on the managed site selected day-roosts only at the tree and plot scale. We hypothesize that greater availability of roosting structures (i.e., abundant large trees and snags) throughout the natural site allowed evening bats to select day-roosts that had favorable landscape characteristics (i.e., closer to water and foraging sites), possibly providing benefits from reduced commuting costs. On the managed site, the relatively young age structure of stands resulted in less-abundant roosting structures throughout the landscape, resulting in selection only at the tree and plot scales. Evening bats appeared to select day-roosts that provide energetic benefits when landscape conditions permitted, however, replicated studies are needed to examine the relationship between energetics and roost availability. Land management on pine landscapes of the southeastern United States that promotes large trees, retention of snags, and an open midstory appears to provide abundant roost structures for evening bats. On managed landscapes, roost sites for evening bats may be provided by retention of forked-topped pines in managed stands and by allowing maturation and senescence of trees in set-aside areas, such as streamside management zones, to promote snag and cavity formation.

Construction and Validation of an Instrument to Measure Environmental Orientations in a Diverse Group of Children

An understanding of children’s environmental orientations is of critical importance as opportunities for authentic contact with nature diminish. Current instruments for measuring children’s environmental attitudes are complex, and few have been tested across diverse audiences. This study employed a mixed-methods approach that included pilot tests, final survey implementation, and interviews to create a survey instrument for assessing the environmental attitudes and awareness of children (N = 254) from different age (6- to 13-yearolds) and ethnic groups (African American, Hispanic, and White). Reliability and validity analyses indicated the scale was a psychometrically sound method for accurately and efficiently measuring children’s perceptions of nature across a demographic range. Eco-affinity and eco-awareness emerged as two distinct components of environmental orientations. This new evaluation tool may help educators and researchers examine the ways children perceive the natural world. It may also help to identify cognitive and affective aspects of existing environmental education programs that need improvement.

Allegheny Woodrat (Neotoma magister) Food Habits in the Central Appalachians

Abstract Declining Allegheny woodrat (Neotoma magister) populations suggest a need for more basic ecological information about the species for proper management. Within the core of the Allegheny woodrats distribution in the central Appalachians, food habits and food resource availability are poorly understood. We collected fecal material from known Allegheny woodrats between November 1997 and December 1998 and used microhistological techniques to describe seasonal food habits in the oak (Quercus spp.), dominated forests of the Ridge and Valley and the northern hardwood forests of the Allegheny Plateau physiographic provinces. We examined dietary differences among seasons within and between provinces. Green vegetation, hard mast, soft mast and fungi were present in Allegheny woodrat diets in both provinces in all seasons. Presence of fungi and soft mast in the diet was higher and more widespread seasonally in the Allegheny Plateau than the Ridge and Valley due, in part, to the more mesic forest conditions and more extensive early successional forest habitat in the Allegheny Plateau. Presence of hard mast in the diet tracked acorn production and availability in both provinces in 1997 and 1998. Significant acorn use on the Allegheny Plateau, where oak-dominated forest stands are rare, highlights the importance of hard mast to Allegheny woodrats. Based on food habits we describe, managers seeking to enhance Allegheny woodrat habitat need to provide a mix of habitat conditions containing abundant green vegetation and optimize production and availability of hard mast, soft mast and fungi.

Sex-specific Summer Roost-site Selection by Seminole Bats in Response to Landscape-level Forest Management

Abstract Although importance of forested corridors to navigating and foraging bats has been documented, the relationship between corridors and roost-site selection has not been studied. From late May to mid-August 2003–2006, we used radiotelemetry to investigate roost-site selection by Seminole bats (Lasiurus seminolus) on an intensively managed landscape with forested corridors in southern South Carolina. We tracked 27 (10 males and 17 females) adult Seminole bats to 90 (41 males and 49 females) diurnal roosts. We found 61% (n = 25) of male and 63% (n = 31) of female roosts in forested corridors, which comprised 11% of the landscape. We modeled roost-site selection with logistic regression and used Akaikes information criterion for small samples (AICc) and Akaike weights to select models relating roost-site selection to landscape-level features. Our results indicated that several factors (i.e., distance to nearest corridor and distance to nearest mature pine stand) influenced roost-site selection and that differences existed between males and females, and among female reproductive condition. Examination of our data suggests that landscape-level features are more important than tree- and plot-level characteristics for roosting by Seminole bats on this managed forest. Corridors may represent a feasible approach to maintaining suitable roosting habitat for Seminole bats in managed forest landscapes.

Evaluation of factors restricting distribution of the endangered Key Largo woodrat.

Abstract We examined a suite of models in an information theoretic framework to identify factors restricting presence of the endangered Key Largo woodrat (Neotoma floridana smalli) throughout its remaining habitat. Models containing variables related to availability of nest sites and mammalian predator abundances were supported by our data. Abundance of natural (large overstory trees) and artificial (rock and debris piles) nest substrate were the most important predictor variables, followed by indices of feral cat and raccoon (Procyon lotor) abundance. We recommend increasing abundance of nest substrate in the short term through addition of artificial nest substrate and in the long term through continued protection of remaining forest habitat.

Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations

Abstract In the southeastern United States, coarse woody debris (CWD) typically harbors high densities of invertebrates. However, its importance as a foraging substrate for southeastern amphibians is relatively unknown. We examined effects of CWD manipulations on diet composition of southern toads (Bufo terrestris) in upland loblolly pine (Pinus taeda) stands in the Coastal Plain of South Carolina. Twelve 9.3-ha plots were assigned one of the following treatments: removal- all CWD ≥10 cm in diameter and ≥60 cm long removed; downed- five-fold increase in volume of down CWD; and unmanipulated control stands. We collected southern toads ≥4 cm snout-vent length (SVL) during 14 d sampling periods in June and October 2002, June 2003 and during a 28 d sampling period in April 2003. We collected 80, 36 and 35 southern toads in control, downed and removal treatments, respectively. We found no difference in relative abundance or frequency of invertebrate groups consumed among treatments (P > 0.05). Average body weight (g), SVL (cm) and stomach content weight (g wet) of individuals also were similar among treatments (P > 0.05). The role of CWD as a foraging substrate for southern toads in loblolly pine stands of the southeastern Coastal Plain may be negligible, at least in the early stages of decay.

Influence of coarse woody debris on the soricid community in southeastern Coastal Plain pine stands.

Abstract Shrew abundance has been linked to the presence of coarse woody debris (CWD), especially downed logs, in many regions in the United States. We investigated the importance of CWD to shrew communities in managed upland pine stands in the southeastern United States Coastal Plain. Using a randomized complete block design, 1 of the following treatments was assigned to twelve 9.3-ha plots: removal (n  =  3; all downed CWD ≥10 cm in diameter and ≥60 cm long removed), downed (n  =  3; 5-fold increase in volume of downed CWD), snag (n  =  3; 10-fold increase in volume of standing dead CWD), and control (n  =  3; unmanipulated). Shrews (Blarina carolinensis, Sorex longirostris, and Cryptotis parva) were captured over 7 seasons from January 2007 to August 2008 using drift-fence pitfall trapping arrays within treatment plots. Topographic variables were measured and included as treatment covariates. More captures of B. carolinensis were made in the downed treatment compared to removal, and captures of S. longirostris were greater in downed and snag compared to removal. Captures of C. parva did not differ among treatments. Captures of S. longirostris were positively correlated with slope. Our results suggest that abundance of 2 of the 3 common shrew species of the southeastern Coastal Plain examined in our study is influenced by the presence of CWD.

Male Seminole Bat Winter Roost-Site Selection in a Managed Forest

Abstract Understanding year-round roost-site selection is essential for managing forest bat populations. From January to March, 2004 to 2006, we used radiotelemetry to investigate winter roost-site selection by Seminole bats (Lasiurus seminolus) on an intensively managed landscape with forested corridors in southeastern South Carolina, USA. We modeled roost-site selection with logistic regression and used Akaikes Information Criterion for small samples (AICc) and Akaike weights to select models relating roost-site selection to plot- and landscape-level variables. We tracked 20 adult male bats to 71 individual roosts. Bats used a variety of roosting structures, including the canopy of overstory trees, understory vegetation, pine (Pinus spp.) needle clusters, and leaf litter. Roost height, structure type, and habitat type were influenced by changes in minimum nightly temperature. On warmer nights, bats selected taller trees in mature forest stands, but when minimum nightly temperatures were <4° C, bats typically were found roosting on or near the forest floor in mid-rotation stands. We recommend avoiding prescribed burning in mid-rotation stands on days when the previous nights temperature is <4 °C to minimize potential disturbance and direct mortality of bats roosting on or near the forest floor. We encourage forest managers to incorporate seasonal changes in roost-site selection to create year-round management strategies for forest bats in managed landscapes.