J. Edward Gates

RESPONSE OF HERPETOFAUNAL COMMUNITIES TO FOREST CUTTING AND BURNING AT CHESAPEAKE FARMS, MARYLAND

Abstract The distribution and abundance of amphibians and reptiles in forest stands subjected to salvage cutting and prescribed burning were compared with their unmanaged counterparts. The study was conducted on the Atlantic coastal plain at Chesapeake Farms near Chestertown, Maryland. Three herpetofaunal trapping arrays were systematically located in each of four forest stand types: hardwood (Hardwood), cut-over hardwood (Cut), mixed pine-hardwood (Pine) and prescribed burn pine (Burn). A total of 3931 individuals representing 29 species were captured in 30,540 trap nights during the spring and summer 1992 and 1993. Felling of hardwoods and prescribed burning of pine resulted in similar responses from the herpetofaunal communitites; Hardwood had the most distinctive herpetofaunal community of the four stands. Adults and young-of-the-year (YOY) of six amphibian species were significantly more abundant in Hardwood than Cut. Only one amphibian species, Pseudacris triseriata, was less abundant in Hardwood than Cut. Total ranid captures did not differ between Hardwood and Cut. Snake and total reptile captures, and Elaphe obsoleta and Eumeces faciatus abundances were significantly less in Hardwood than Cut. Hardwood also had fewer small mammals than Cut, particularly Microtus pennsylvanicus and Zapus hudsonius, that might serve as prey for large snakes. Adults of four amphibian species, YOY of five amphibian species, and three reptiles (Carphophis amoenus, Storeria dekayi and Thamnophis sirtalis) were significantly more abundant in Pine than Burn; two reptile species (Coluber constrictor and Lampropeltis getula) were significantly less abundant. Potential small mammal prey of the latter two snakes were not significantly different between Pine and Burn; however, Zapus hudsonius was less abundant in Pine than in Burn. More amphibians were captured in Hardwood and Pine stands than in their respective logged and burned counterparts. The trend for reptiles tended to depend on the mix of species present and their habitat preferences. Greater canopy cover and depth of leaf litter in Hardwood and Pine stands likely had a moderating effect on temperature and helped to maintain a moist microenvironment for mesophilic species. Disturbance of a small patch of forest could locally decrease herpetofaunal diversity, but diversity on a much larger scale would likely increase.

COWBIRDS BREEDING IN THE CENTRAL APPALACHIANS: SPATIAL AND TEMPORAL PATTERNS AND HABITAT SELECTION

To help minimize the impact of brood parasitism by female Brown-headed Cowbirds (Molothrus ater) on Nearctic-Neotropical migrants, we studied their spatial and temporal patterns and habitat selection throughout the breeding season. The study was conducted on an anthropogenic forest landscape in the central Appalachian Mountains of western Maryland. This landscape was characterized by different forest types and stages of succession resulting from logging, agriculture, and low-density housing development, as well as by natural and human-made corridors. Using radiotelemetry, cowbird movements were monitored in 3-h time periods during the day, beginning at 0500 hours Eastern Standard Time. Females were generally alone or with one or two other individuals from 0500 to 1100 hours. They were located in deciduous forest and brush near edges formed by road, power line, or stream corridors and other clearings, presumably searching for nests to parasitize. Breeding core ranges of individual females tended to be spatially separated from one another. Females would travel, on average, 2.3 km from breeding to feeding areas. From 1100 hours until dusk, feeding aggregations of ≥12 individuals could be found in grazed pasture or other areas of short grass. Feeding core ranges overlapped considerably. At dusk, cowbirds would fly an average of 3.0 km to roosting areas in deciduous forest near (X¯ = 1.3 km) where they would be found the next morning, presumably breeding. Cowbirds roosted singly or in small aggregations in trees near forest edges. Although the mean home range was 1592 ha, only 3.5% or 31.6 ha, on average, was actually used for different activities. Most individuals had at least two feeding core ranges (X¯ = 16.5 ha total), one breeding core range (X¯ = 9.5 ha), and one roosting core range (X¯ = 1.8 ha) or combination roost/breed core range (X¯ = 9.8 ha). Multiple-use core ranges were generally larger than single-use core ranges. Breeding and roosting core ranges were often elongated, with the long axis paralleling a linear canopy opening, e.g., a road, power line, or stream corridor. Multiple-use core ranges were more circular in shape. Breeding and roosting core-range centroids in the forest were often 22.5 cm dbh) snags than were found within forest interior >250 m from an edge. Conservation measures designed to reduce use of large forest tracts by cowbirds in this region would include eliminating feeding areas, minimizing canopy openings or edges, and perhaps managing existing edges in order to disperse nests of potential host species.

Distribution and activity of bats at local and landscape scales within a rural–urban gradient

We examined the relationship between bat species activity and composition and the extent of forest cover and urbanization in and adjacent to 11 U.S. National Park Service, National Capital Region Parks in Maryland, Virginia, West Virginia, and Washington, D.C., from 2003–2004, using mist nets, harp traps, acoustical detectors, and visual observations in a variety of habitats. Our efforts included 363 trap nights across 74 sites along with acoustical sampling at 362 sites. We captured 383 bats and identified 6,380 echolocation passes of 6 species. Both overall and species-specific activities were affected more by forest fragmentation within parks than by urbanization adjacent to parks. With an ability to exploit anthropogenic structures for day-roosts, big brown bats (Eptesicus fuscus) were the most ubiquitous and probably the most abundant species in NCR Parks, particularly in forested, urban parks. Northern myotis (Myotis septentrionalis), and to a lesser extent, little brown myotis (Myotis lucifugus) were more prevalent in forested, rural parks of the Ridge and Valley and Blue Ridge than in eastern, less forested urban parks of the Piedmont and Coastal Plain physiographic provinces. Retention of larger, residual forest tracts and day-roosting habitat (i.e., trees and snags) would be beneficial to most species, as urban expansion continues throughout the region.

Monitoring seasonal bat activity on a coastal barrier island in Maryland, USA

Research on effects of wind turbines on bats has increased dramatically in recent years because of significant numbers of bats killed by rotating wind turbine blades. Whereas most research has focused on the Midwest and inland portions of eastern North America, bat activity and migration on the Atlantic Coast has largely been unexamined. We used three long-term acoustic monitoring stations to determine seasonal bat activity patterns on the Assateague Island National Seashore, a barrier island off the coast of Maryland, from 2005 to 2006. We recorded five species, including eastern red bats (Lasiurus borealis), big brown bats (Eptesicus fuscus), hoary bats (Lasiurus cinereus), tri-colored bats (Perimyotis subflavus), and silver-haired bats (Lasionycteris noctivagans). Seasonal bat activity (number of bat passes recorded) followed a cosine function and gradually increased beginning in April, peaked in August, and declined gradually until cessation in December. Based on autoregressive models, inter-night bat activity was autocorrelated for lags of seven nights or fewer but varied among acoustic monitoring stations. Higher nightly temperatures and lower wind speeds positively affected bat activity. When autoregressive model predictions were fitted to the observed nightly bat pass totals, model residuals >2 standard deviations from the mean existed only during migration periods, indicating that periodic increases in bat activity could not be accounted for by seasonal trends and weather variables alone. Rather, the additional bat passes were attributable to migrating bats. We conclude that bats, specifically eastern red, hoary, and silver-haired bats, use this barrier island during migration and that this phenomenon may have implications for the development of near and offshore wind energy.

Home Ranges, Habitat Selection and Mortality of Ring-necked Pheasants (Phasianus colchicus) in North-central Maryland

Abstract Between 4 January and 15 May 1988, we captured 16 female and 10 male ring-necked pheasants (Phasianus colchicus) in north-central Maryland at the southern edge of their North American range and fitted them with radiotransmitters. We monitored their movements on an agricultural landscape encompassing 2002 ha from the day of capture until death, transmitter failure or 15 December 1988. Eight of 16 females and seven of 10 males survived to the nesting season. Predation accounted for 61% of the mortality of adult pheasants. Seven males and 12 females, each with ≥30 fixes per analytical time period (winter, nesting, postnesting or maximum), were used in analysis of home and core ranges, seasonal movements and habitat selection and use. Home range sizes did not differ significantly between sexes or among seasons. Pheasants had significantly larger core ranges during the nesting season than during winter or postnesting seasons. Pheasants selected home ranges with a higher proportion of shrublands and wetlands than expected from availability within the study area. A comparison of habitat use within core ranges to that available within home ranges in winter showed that forests were significantly less used than wetlands, croplands, shrublands and developed lands. There were no significant differences in proportional habitat use of home versus core ranges during the nesting season. Based on our study, conservation measures should include (1) enhancing preferred nesting cover by compensating landowners for delaying or not mowing hay fields or leaving crop fields fallow and (2) providing suitable dispersed male territory cover (i.e., shrubs or woody cover at crop borders) around existing patches of winter cover (i.e., wetlands and shrublands) and in close proximity to nesting cover.

Peaking of World Oil Production

Nonrenewable and renewable energy sources make up the two major energy categories of interest to our industrial civilization. Nonrenewable energy includes different fossil fuels (coal, oil, natural gas) that were formed over millions of years, as well as nuclear . Once used, they are no longer available in any time period of interest to humans. Renewable energy , on the other hand, is so-called free energy, such as the sun (solar), wind, biomass , by-products of fermentation or decomposing organic matter (alcohol, biodiesel, methane) , geothermal, etc., that only has to be harnessed, used, or converted to another form, for example, electricity. Any evaluation of fossil-fuel energy and proposed alternatives requires knowledge of the interrelations between heat, work, and internal energy of a system, in other words, the study of thermodynamics.

Nesting Ecology and Microhabitat of the Eastern Phoebe in the Central Appalachians

-In 1984, a study of the eastern phoebe (Sayornis phoebe) was conducted on the Appalachian Plateau in western Maryland, principally in the Savage River State Forest. Fledging success and mortality patterns were used as indicators of differences in quality of nest-site microhabitats. A total of 229 fledglings resulted from 84 nesting attempts, an average of 2.73 fledglings per attempt. Fledging success was 61.4%, with early nests generally more successful than late nests. Fledging success was similar among nesting structures, with adherent nests having higher success than statant nests, except on rock outcrops. However, late-adherent nests on rock outcrops did have higher fledging success than late-statant nests. The success of new-active and old-active nests was the same. Losses attributed to predators amounted to 70.1% of all losses. Losses attributed to small predators (55.6%) were significantly higher than that from large predators (14.6%). Other losses were attributed to nests falling (13.9%), human disturbance (5.6%), hatching failure (4.2%), adult death/desertion (3.5%) and inclement weather (2.8%). Losses ascribed to small predators increased from early to late nesting attempts on all nesting structures, but less so for adherent nests on rock outcrops. The principal nest predator was probably the eastern chipmunk (Tamias striatus). Stepwise discriminant function analysis was used to distinguish between microhabitats of high-success (>60%) and low-success (?60%) phoebe nests. Evergreen canopy cover (%), height to nest rim and distance to nearest understory tree were greater at high-success nests; while angle of recess in which the nest was built was smaller. Microhabitat variables with no differences among nesting structures, and therefore probably important in overall nestsite selection, included height of rock outcrop or other structure at the nest location, height to nest rim, width of shelf used for support of nest, length of overhanging structure above nest, height to underhanging structure below nest, height of understory trees and percent evergreen canopy cover. Variables associated with access to the nest tended to affect success more than others.

Selection of Sites for Winter Night Beds by White-tailed Deer in a Hemlock-Northern Hardwood Forest

Environmental factors influencing selection of sites for winter night beds by white-tailed deer (Odocoileus virginianus) were evaluated in an eastern hemlock (Tsuga canadensis) northern hardwood forest in western Maryland. Sixty-two microhabitat variables were sampled at 140 bed sites to characterize vegetation structure and cover. Microhabitat variables at bed sites were compared to 100 random sites to determine factors involved in site selection. Principal components analysis (PCA) of the random sites using variables important in night-bed selection resulted in four PCs that defined a four-dimensional PC space upon which the microhabitats of the 140 bed sites were plotted. Night beds were characterized by more coniferous cover directly above the bed, a greater frequency of eastern hemlock trees N and W of the bed, an open southeastern exposure, a low minimum distance to the nearest tree and a high spatial heterogeneity of trees.

Spring Migration and Roost Selection of Female Myotis leibii in Maryland

Abstract Many aspects of the ecology of Myotis leibii (Eastern Small-footed Myotis) are unknown due to the rarity of the species throughout its range in the eastern United States. Few studies have examined Eastern Small-footed Myotis migration and roosting behavior. Until a recent discovery of a population of Eastern Small-footed Myotis using an abandoned railroad tunnel in western Maryland, most observations from the state were limited to records of a few individuals at scattered caves, mines, and tunnels. We used harp traps to capture Eastern Small-footed Myotis at an abandoned railroad tunnel located in Allegany County, in spring 2007. We captured 47 Eastern Small-footed Myotis and equipped four females with radio transmitters. Telemetry revealed that female Eastern Small-footed Myotis migrated ≤ 1.1 km to nearby shale barrens and roosted in rock outcrops of various sizes during spring. Females moved <50 m between successive diurnal roosts, which did not differ from random sites located within the shale barrens in terms of site characteristics. Migratory distances and, consequently, geographic ranges of female Eastern Small-footed Myotis probably are influenced by the availability of hibernacula and roosting sites across the landscape.

Bats of Assateague Island National Seashore, Maryland

ABSTRACT As significant nocturnal insectivores, bats are an integral part of many ecosystems. Determining bat species composition in an area is a critical first step in managing for this important resource. Little information exists concerning the bat species composition of Marylands Coastal Plain, which is located on the northern periphery of the geographic ranges of five bat species occurring in the southeastern United States. We conducted mist net surveys for bats at Assateague Island National Seashore, a barrier island on Marylands coast, in summer 2005 and summer and autumn 2006. In 2005 we captured 133 bats representing three species, including two big brown bats (Eptesicus fuscus), 129 eastern red bats (Lasiurus borealis) and two purported Seminole bats (L. seminolus). In 2006 we captured 60 eastern red bats in summer and autumn combined. We used Anabat II bat detectors to conduct long-term acoustic monitoring on the island year round and documented three additional bat species, including silver-haired bats (Lasionycteris noctivagans), hoary bats (L. cinereus) and eastern pipistrelles (Pipistrellus subflavus). We documented silver-haired bats during spring and autumn, probably as they were migrating through the area. We used Anabat II bat detectors to conduct short-term monitoring of bat activity at five habitat types during summer 2005 and 2006 and found that total bat activity and eastern red bat activity were similar among forested areas, freshwater pools and bayside marshes. In shrublands, total bat activity and eastern red bat activity was higher than at beach areas, lower than in forested areas and similar at freshwater pools and bayside marshes. The loblolly pine (Pinus taeda) – dominated forests at ASIS provide roosting and foraging habitat mostly for eastern red bats, but also for other migratory bat species.