Glaucomys Volans Research Articles

Ectoparasites and gastrointestinal helminths of southern flying squirrels in southeast Georgia.

Southern flying squirrels (Glaucomys volans) from southeastern Georgia were examined for ectoparasites and gastrointestinal helminths. Ten species of ectoparasites were recovered, including 3 species of sucking lice (Hoplopleura trispinosa, Microphthirus uncinatus, and Neohaematopinus sciuropteri), 1 species of flea (Orchopeas howardi), 2 species of ticks (Amblyomma maculatum and Ixodes scapularis), 3 species of mesostigmatid mites (Androlaelaps casalis, A. fahrenholzi, and Haemogamasus ambulans), and 1 species of chigger (Leptotrombidium peromysci). Only the sucking lice and fleas were common on this host. M. uncinatus is reported for the first time from eastern North America. The 2 most commonly collected ectoparasites, N. sciuropteri (prevalence = 63%) and O. howardi (prevalence = 47%), have previously been shown to be vectors of the rickettsial zoonotic agent that causes sporadic epidemic typhus. Also, 3 nematodes (Citellinema bifurcatum, Strongyloides robusius, and Syphacia thompsoni), 1 unidentified cestode, and 1 acanthocephalan (Moniliformis clarki) were found in flying squirrel gastrointestinal tracts. With the exception of S. thompsoni, which was common and relatively abundant in the cecum (prevalence = 94%, intensity = 51+/-12), both the prevalence and intensity of helminth parasites were low. The nematode S. thompsoni and the acanthocephalan M. clarki are new state records for tree squirrels in Georgia.

Ectoparasites and Gastrointestinal Helminths of Southern Flying Squirrels in Southeast Georgia

Ectoparasites and Gastrointestinal Helminths of Southern Flying Squirrels in Southeast Georgia

Availability of nest sites does not limit population size of southern flying squirrels

Among factors that may limit population size, nest site is generally considered important for cavity-nesting species. We tested the hypothesis that nest-site availability limits population size in the southern flying squirrel (Glaucomys volans) by examining the effect of experimentally increasing the number of nest sites. We compared population sizes before and after adding 100 nest boxes (high-quality nests, increasing overall nest density by at least about 65%) on each of three experimental sites on the Savannah River Site in South Carolina. We also compared the experimental populations with three reference (unmanipulated) sites in a paired-block experimental design. All six populations were similarly monitored with livetrapping grids, and flying squirrels readily nested in the supplemental boxes. We predicted that population size would increase where nest sites were added. No increases in population size were observed after nest boxes were added to the three experimental sites, however, nor were populations higher on the experimental sites than on the reference sites. The lack of increase in population size after nest boxes were added demonstrates that the availability of nest sites was not limiting the size of these populations.

IDENTIFICATION OF NEST PREDATORS AT FARM/FOREST EDGE AND FOREST INTERIOR SITES

Using cameras at artificial ground nests we found no major quantitative differences in species richness or the relative abundance of nest predators photographed in farm/forest edge and forest-interior sites at five locations in eastern Pennsylvania. Raccoons (Procyon lotor) were the most commonly photographed visitors to nests at both farm/forest edge and forest interior sites, followed by female Baltimore Orioles (Icterus galbula), southern flying squirrels (Glaucomys volans), gray squirrels (Sciurus carolinensis), eastern chipmunks (Tamias striatus), and Gray Catbirds (Dumetella carolinensis). Rate of egg loss was higher at the edges than in the forest interior. Although the total number of photographs of predators averaged 11 among the five edge sites and 7.4 among interior sites, this was not significantly different.

LANDSCAPE-LEVEL CORRELATES OF SMALL-MAMMAL ASSEMBLAGES IN FOREST FRAGMENTS OF FARMLAND

We studied effects of forest fragmentation on 15 species of small mammals, including 6 species of forest-dwelling granivorous rodents, in the Indian Pine watershed of west-central Indiana. Presence‐absence and population densities of small mammals were assessed in spring in 35 woodlots of various sizes (0.1‐150 ha) and 2 continuous forest sites ( .1,000 ha) using live traps in 1992‐1996. Presence‐absence and population density were related to landscape attributes using logistic and multiple linear regression models, respectively. Species richness of forest-dwelling small mammals increased with area and was highest in continuous forest sites. Nested subsets of the full complement of species were found in smaller woodlots. White-footed mice (Peromyscus leucopus) were ubiquitous, and eastern chipmunks (Tamias striatus) were nearly ubiquitous across the landscape; densities of both species were related inversely to forested area. Fox squirrels ( Sciurus niger) were found at 84% of study sites, and they did not respond negatively to isolation of forest patches. Red squirrels (Tamiasciurus hudsonicus) were unevenly distributed across the landscape and were found most often in woodlots with large core areas and simple shapes, possibly indicating sensitivity to edge. Southern flying squirrels ( Glaucomys volans) and gray squirrels (S. carolinensis) were restricted to continuous forest sites and .4.6-ha woodlots adjacent to other wooded habitat. Species of small mammals differ appreciably in their sensitivities to agriculturally induced fragmentation of forests. Interspecific differences within this assemblage were not due solely, or even primarily, to body size. Rather, differential responses of species to fragmentation likely resulted from variation in habitat breadth and ability to move through an agricultural matrix.

SELECTION OF MAST BY GRANIVOROUS RODENTS OF THE CENTRAL HARDWOOD FOREST REGION

We used cafeteria-style feeding trials with 8 types of mast in various combinations to examine differences in resource selection among 5 syntopic species of granivorous forest rodents in west-central Indiana. Patterns of resource selection corresponded to differences in phylogeny and body size of granivores, with greatest similarities among closely related species of similar body size. Breadth of resource use varied inversely with body size in our trials. Resource selection by Sciurus carolinensis, S. niger, and Tamiasciurus hudsonicus was correlated positively with caloric and lipid content of mast and its size, whereas selection by Glaucomys volans was correlated negatively with the percentage of protective tissue associated with seeds. Laboratory trials indicated that T. hudsonicus and G. volans discriminate among mast of comparable physical and chemical composition on the basis of size, with a preference for larger seeds. Contrary to our expectations, T. hudsonicus, a recent immigrant from the boreal forest, did not exhibit a preference for seeds of red pine (Pinus resinosa) relative to mast of hardwood species. G. volans and Peromyscus leucopus tended to consume perishable white oak acorns immediately and to cache a substantial portion of less perishable seeds of nonpreferred species. Our results demonstrate the potential for considerable overlap in resource use among members of this guild. Guild members also seem to be affected differentially by physical and chemical properties of mast, and patterns of resource selection reflect contrasting foraging constraints under which these animals operate.

OBSERVATIONS OF WOOD THRUSH NEST PREDATORS IN A LARGE CONTIGUOUS FOREST

We used inexpensive (<$30) cameras to document predators at active Wood Thrush (Hylocichla mustelina) nests in Great Smoky Mountains National Park. We observed such predators as black rat snakes (Elaphe obsoleta), American Crows (Corvus brachyrhynchos), southern flying squirrels (Glaucomys volans), and black bears (Ursus americanus) remove the contents of nests. Camera installation had no measurable effect on nest survival; daily nest survival was approximately 0.96 for nests with and without cameras. However, placement of an artificial egg trigger in the nest appeared to reduce hatching success. The immobile egg trigger might have interfered with the female Wood Thrush's ability to incubate her eggs. The variety of nest predators observed and the moderate daily survival rates recorded suggest that predation is an important constraint on Wood Thrushes nesting in large contiguous forests.

Availability of nest sites does not limit population size of southern flying squirrels

Among factors that may limit population size, nest site is generally considered important for cavity-nesting species. We tested the hypothesis that nest-site availability limits population size in the southern flying squirrel (Glaucomys volans) by examining the effect of experimentally increasing the number of nest sites. We compared population sizes before and after adding 100 nest boxes (high-quality nests, increasing overall nest density by at least about 65%) on each of three experimental sites on the Savannah River Site in South Carolina. We also compared the experimental populations with three reference (unmanipulated) sites in a paired-block experimental design. All six populations were similarly monitored with livetrapping grids, and flying squirrels readily nested in the supplemental boxes. We predicted that population size would increase where nest sites were added. No increases in population size were observed after nest boxes were added to the three experimental sites, however, nor were popula...

Assessing Southern Flying Squirrel, Glaucomys volans, habitat selection with kernel home range estimation and GIS

Assessing Southern Flying Squirrel, Glaucomys volans, habitat selection with kernel home range estimation and GIS

Effects of southern flying squirrels Glaucomys volans on red‐cockaded woodpecker Picoides borealis reproductive success

AbstractAnecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Glaucomys volans) use of the endangered red‐cockaded woodpecker's (RCW, Picoides borealis) nest and roost cavities may negatively affect RCW populations. We conducted a controlled experiment to determine the effects of SFSs on RCW reproductive success. During the 1994 and 1995 breeding seasons, SFSs were removed from 30 RCW clusters and 32 clusters served as controls. SFSs were the most frequently encountered occupants of RCW cavities and used 20–33% of RCW cavities in control and treatment clusters over both years. Treatment groups produced significantly more successful nests (≥ 1 fledgling) than control groups in 1994. In 1995 however, there was no difference in the number of successful nests. In both years, RCW groups nesting in treatment clusters produced significantly more fledglings than groups in control clusters in each of four experimental areas, averaging approximately 0.7 additional fledglings per nesting group. Loss of entire clutches or broods, possibly as a result of predation or abandonment, was a major factor limiting reproduction in control groups in 1994. In contrast, differences in partial brood loss appeared to be the cause of differential fledging success in 1995. Usurpation of RCW roost cavities by SFSs may have placed greater energetic demands on RCWs for cavity defence or thermoregulation, thus reducing energy available for reproduction. Our results show that SFS use of RCW cavities during the breeding season has a significant impact on RCWs and that management of RCW populations should include activities that either minimize SFS populations in RCW clusters or limit access of SFSs to RCW cavities.

Effects of southern flying squirrels Glaucomys volans on red-cockaded woodpecker Picoides borealis reproductive success

Anecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Glaucomys volans) use of the endangered red-cockaded woodpecker's (RCW, Picoides borealis) nest and roost cavities may negatively affect RCW populations. We conducted a controlled experiment to determine the effects of SFSs on RCW reproductive success. During the 1994 and 1995 breeding seasons, SFSs were removed from 30 RCW clusters and 32 clusters served as controls. SFSs were the most frequently encountered occupants of RCW cavities and used 20–33% of RCW cavities in control and treatment clusters over both years. Treatment groups produced significantly more successful nests (≥ 1 fledgling) than control groups in 1994. In 1995 however, there was no difference in the number of successful nests. In both years, RCW groups nesting in treatment clusters produced significantly more fledglings than groups in control clusters in each of four experimental areas, averaging approximately 0.7 additional fledglings per nesting group. Loss of entire clutches or broods, possibly as a result of predation or abandonment, was a major factor limiting reproduction in control groups in 1994. In contrast, differences in partial brood loss appeared to be the cause of differential fledging success in 1995. Usurpation of RCW roost cavities by SFSs may have placed greater energetic demands on RCWs for cavity defence or thermoregulation, thus reducing energy available for reproduction. Our results show that SFS use of RCW cavities during the breeding season has a significant impact on RCWs and that management of RCW populations should include activities that either minimize SFS populations in RCW clusters or limit access of SFSs to RCW cavities.

Selection of nest trees by southern flying squirrels (Sciuridae: Glaucomys volans) in Arkansas

AbstractNatural nest‐site selection was investigated in 50 radiocollared southern flying squirrels Glaucomys volans during spring and summer, 1994–1996, in the Ouachita National Forest of Arkansas. Squirrels nested in 226 trees in a variety of habitats at five study areas. Contrary to previous reports describing southern flying squirrels as habitat generalists, in this study squirrels showed selection in both the habitat and tree type in which nests were placed. Where it was available, mature pine–hardwood forest was selected for nesting. Young (&lt; 15 years old) and immature (15–40 years old) pine plantations and harvested areas were avoided as nesting habitats. At harvested study areas, squirrels nested in protected riparian mature forest strips (greenbelt) along, and 10–20 m either side of, intermittent creeks and in adjacent mature forests. Squirrels constructed only outside nests in pine trees. In mature pine–hardwood forest, pines were used for outside nests more frequently than hardwoods; in greenbelt habitat, pines and hardwoods were chosen equally for outside nests. Both outside and cavity nests were found in hardwoods; standing dead trees (snags) contained only cavity nests. Snags were selected over hardwoods for cavity nesting in both mature pine–hardwood forest and greenbelt habitat. All hardwood species and all decay classes of snags were used for diurnal nesting in greater frequency than expected. Considering both cavity and outside nest‐site selection, pines were used less than expected. Results suggest that mature forests are optimal flying squirrel nesting habitats and should be retained adjacent to harvested areas to provide resources to squirrels abandoning stands after disturbance. Within harvested areas, nesting habitat can be substantially improved through the retention of overstory hardwoods and snags, as well as protection of mature forest strips along drainages.

Selection of nest trees by southern flying squirrels (Sciuridae: Glaucomys volans) in Arkansas

Natural nest-site selection was investigated in 50 radiocollared southern flying squirrels Glaucomys volans during spring and summer, 1994–1996, in the Ouachita National Forest of Arkansas. Squirrels nested in 226 trees in a variety of habitats at five study areas. Contrary to previous reports describing southern flying squirrels as habitat generalists, in this study squirrels showed selection in both the habitat and tree type in which nests were placed. Where it was available, mature pine–hardwood forest was selected for nesting. Young (< 15 years old) and immature (15–40 years old) pine plantations and harvested areas were avoided as nesting habitats. At harvested study areas, squirrels nested in protected riparian mature forest strips (greenbelt) along, and 10–20 m either side of, intermittent creeks and in adjacent mature forests. Squirrels constructed only outside nests in pine trees. In mature pine–hardwood forest, pines were used for outside nests more frequently than hardwoods; in greenbelt habitat, pines and hardwoods were chosen equally for outside nests. Both outside and cavity nests were found in hardwoods; standing dead trees (snags) contained only cavity nests. Snags were selected over hardwoods for cavity nesting in both mature pine–hardwood forest and greenbelt habitat. All hardwood species and all decay classes of snags were used for diurnal nesting in greater frequency than expected. Considering both cavity and outside nest-site selection, pines were used less than expected. Results suggest that mature forests are optimal flying squirrel nesting habitats and should be retained adjacent to harvested areas to provide resources to squirrels abandoning stands after disturbance. Within harvested areas, nesting habitat can be substantially improved through the retention of overstory hardwoods and snags, as well as protection of mature forest strips along drainages.

Effects of Southern Flying Squirrels on Nest Success of Red-Cockaded Woodpeckers

Recovery efforts for endangered red-cockaded woodpeckers (Picoides borealis) often include control of southern flying squirrels (Glaucomys volans). Nevertheless, few studies demonstrate directly that this control improves nest success of red-cockaded woodpeckers. and no experimental studies have evaluated what form of flying squirrel management is most effective. Therefore, in 1996 and 1997 at Fort Stewart, Georgia, we quantified the nesting suecess of red-cockaded woodpeckers in 30 cavity-tree clusters from which flying squirrels were removed. 30 clusters in which flying squirrels were excluded from cavities with squirrel-excluder devices. and 30 control clusters with no flying squirrel management. Removal or exelusion of flying squirrels did not affect the likelihood that red-cockaded woodpeckers would initiate a nest or the median date the first egg was laid in either year. In 1996 (but not 1997), red-cockaded woodpeckers were more likely to nest successfully (produce >1 fledgling) in clusters from which flying squirrels were removed. However, in both years of our study, nests in flying squirrel removal clusters were more likely to experience partial nest loss (disappearance of a portion of their eggs or nestlings). As a net result. the number of eggs, nestlings. and fledglings did not differ among treatments in 1996 or 1997. Removal or exclusion of flying squirrels did not increase the percentage of clusters fledging young or the number of young fledged per cluster. We sugges routine control of flying squirrels is not necded in healthy populations of red-cockaded woodpeckers.

First Record of the Least Weasel, Mustela nivalis (Carnivora: Mustelidae), from the Coastal Plain of Virginia

The first record of the least weasel, Mustela nivalis, for the Coastal Plain of Virginia is reported for a site more that 100 km from the nearest Piedmont records. The least weasel in now known in Virginia from seven sites in the mountains, two in the Piedmont, and this Coastal Plain record. The least weasel, Mustela nivalis, has a circumboreal distribution that includes most of northern North America (Sheffield and King 1994). In the eastern United States, the range of the subspecies M. n. allegheniensis Rhoads extends down the Appalachians to North Carolina and Tennessee (Sheffield and King 1994). At the time of the second symposium on Virginia's endangered species, M. nivalis was known from Virginia on the basis of 13 specimens from two sites in the Upper Piedmont and widely scattered localities in the mountains (Handley 1991:598). This report is on the first known specimen from the Coastal Plain of Virginia. On 31 March 1997 an adult female M. nivalis was collected (Virginia Commonwealth University Mammal Collection number 12617) 4.2 km northeast of Bowling Green, Caroline County (Fig. 1). This site is 108 km southeast of a piedmont record near Rectortown in Fauquier County, Virginia (Handley 1991:598), and 105 km south of a lower piedmont site in Montgomery County, Maryland, 19 km west of Glen Echo on the north bank of the Potomac River (Handley 1991:555). The site is 15 km east of the Fall Line. The altitude of the study area ranges from 30 to 70 m above sea level, and flat areas are interrupted by rolling and occasional steep hills. The weasel was collected in a 3.8-liter pitfall trap as part of a study of small mammal assemblages at Fort A. P. Hill, a U.S. Army training installation. Sampling in the study was conducted with pitfall arrays (modified after Handley and Varn 1994) and Museum Special mouse traps in 11 habitat types (three sites/habitat type; 33 sites total) that ranged from grassy meadow to mature deciduous forest. Trapping conducted from 1 March 1997 to 20 October 1997 amassed a 1 Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012; 2 Department of Biology, University of Richmond, Richmond, VA 23173. 1999 6(3): 238-240 This content downloaded from 157.55.39.181 on Thu, 29 Sep 2016 06:23:02 UTC All use subject to http://about.jstor.org/terms A.S. Bellows, J.F. Pagels, and J.C. Mitchell total of 28,616 trap nights. A trap night represents the amount of time between trap checks, approximately 24 hr in this study. Habitat at the site where the specimen was captured was forested by a mix of conifer and deciduous species. Trees with a dbh of 4 cm or greater were American holly (Ilex opaca, 18.4%), loblolly pine (Pinus taeda, 15.5%), Virginia pine (P. virginiana, 13.8%), sweetgum (Liquidambar styraciflua, 17.8%) dogwood (Cornus florida, 11.5%), red maple (Acer rubrum, 5.2%) southern red oak (Quercus falcata, 5.2%), white oak (Q. alba, 4.0%), northern red oak (Q. rubra, 3.4%), black cherry (Prunus serotina, 2.9%), sassafras (Sassafras albidum, 1.7%) and black oak (Q. velutina, 0.6%). Canopy openness was 27% and a subcanopy was present at 47% of 200 points on a line intercept (method modified after Canfield 1941). Blueberry (Vaccinium spp.) was present at 38.0% of the points. Downed woody debris consisting of logs and limbs that ranged from 0.5 to 15.5 cm in diameter (mean 5.1 cm) was present at 24% of the points. Other small mammal species captured at the site for both trap types were Peromyscus leucopus (N=34, 66.7%), Blarina brevicauda (N=6, 11.8%), Sorex longirostris (N=6, 11.8%), Microtus pennsylvanicus (N=1, 2.0%), M. pinetorum (N=1, 2.0%), Glaucomys volans (N=1, 2.0%), and Tamias striatus (N=1, 2.0%). Considering both pitfall traps and snap traps, there were collectively 886 trapnights associated with

Demographic and Behavioral Responses of Southern Flying Squirrels to Experimental Logging in Arkansas

Demographic and Behavioral Responses of Southern Flying Squirrels to Experimental Logging in Arkansas

Dynamic Foraging Behavior in the Southern Flying Squirrel (Glaucomys volans): Test of a Model

Abstract Foraging behavior of the southern flying squirrel was studied under conditions of declining photoperiod and temperature. Experiments tested predictions derived from a theoretical model suggesting hickory (Carya spp.) nuts as the optimal food for flying squirrels at temperatures below −10 C. Above this temperature flying squirrels could meet their daily energy needs more quickly on a diet of acorns. During a declining photoperiod and mild temperatures flying squirrels stored hickory nuts whereas acorns were usually eaten at the site of discovery. Test animals foraging at low temperatures significantly increased the number of hickory nuts consumed and decreased the number of acorns consumed. By eating acorns in the autumn and storing hickory nuts for winter consumption flying squirrels make use of a dynamic foraging strategy that allows optimal use of both autumn and winter food resources.

Observations on quantitative cognition in Southern Flying Squirrels, Glaucomys volans

Observations on quantitative cognition in Southern Flying Squirrels, Glaucomys volans

An Experimental Test of Interspecific Competition for Red-Cockaded Woodpecker Cavities

To test whether the presence of nest boxes near red-cockaded woodpecker (RCW, Picoides borealis) cavity trees reduced cavity use by other species and improved RCW reproductive success on the Francis Marion National Forest in coastal South Carolina, we placed 3 nest boxes in each of 62 experimental clusters and designated 61 clusters as controls. Our observations of nest box and cavity use showed that nest boxes were somewhat effective in reducing cavity use and that eastern bluebirds (Sialia sialis) and southern flying squirrels (Glaucomys volans) were the most frequent users of nest boxes and cavities. Bluebirds preferred nest boxes to cavities in both years and flying squirrels showed significant preference for nest boxes in 1992. Pretreatment monitoring (1990) of RCW reproductive performance showed no significant differences between control and experimental groups. However, posttreatment monitoring showed that in 1991 RCWs in experimental clusters were significantly more likely to nest than RCWs in control clusters; in 1991 and 1992, they were more likely to fledge ≥1 young. Further, RCWs were less likely to initiate a nest if≥1 cavity was occupied by a non-RCW species than if no cavities in the cluster were occupied by a non-RCW species. These results indicate that RCW cavities were subject to interspecific competition and that nest boxes may be an effective means of reducing competition, particularly when the number of cavities is limited.

Using Geographic Information Systems To Determine Home Range of the Southern Flying Squirrel (Glaucomys volans)

-Home ranges of 12 southern flying squirrels (Glaucomys volans) were studied in the Ouachita Mountains of west-central Arkansas during the winters of 1990-1991 and 1991-1992. Because traditional planimetric home ranges do not account for differences in topography, a Geographic Information System (GIS) which incorporated topography was also used to determine home range. Mean female and male planimetric and (topographical) home-range estimates were 3.8 ha (3.9 ha) and 7.8 ha (9.0 ha), respectively. Differences in home-range size were not statistically significant between sexes, however, home-range estimates of males were more variable. Topographic estimates were significantly larger than planimetric estimates. The GIS more clearly represents home range with respect to habitat characteristics in the context of topographic features and it should be used in future studies.