David C. Guynn

EFFECTS OF GROUP-SELECTION OPENING SIZE ON BREEDING BIRD HABITAT USE IN A BOTTOMLAND FOREST

Research on the effects of creating group-selection openings of various sizes on breeding birds habitat use in a bottomland hardwood forest of the Upper Coastal Plain of South Carolina. Creation of 0.5-ha group selection openings in southern bottomland forests should provide breeding habitat for some field-edge species in gaps and habitat for forest-interior species and canopy-dwelling forest-edge species between gaps provided that enough mature forest is made available.

Factors affecting salamander density and distribution within four forest types in the Southern Appalachian Mountains

Abstract We used a terrestrial vacuum to sample known area plots in order to obtain density estimates of salamanders and their primary prey, invertebrates of the forest floor. We sampled leaf litter and measured various vegetative and topographic parameters within four forest types (oak–pine, oak–hickory, mixed mesophytic and northern hardwoods) and three age classes (0–12, 13–39, and ≥40 years) over two field seasons within the Wine Spring Creek Ecosystem Management area in western North Carolina. We found salamanders preferred moist microsites across all forest types with the highest salamander densities occurring on sites with a northern and/or eastern exposure and within northern hardwood forests. Salamander densities were lowest on 0–12-year plots, yet were equal on 13–39 and ≥40-year plots, suggesting a much quicker recovery from the impact of clearcutting than reported by previous researchers. Overall invertebrate densities did not influence salamander density or distribution although, plots in which salamanders were captured, harbored significantly higher numbers of snails than plots in which salamanders were not captured. We discuss the importance of calcium to salamanders and snails as a possible source thereof.

Small mammal microhabitat use on young loblolly pine regeneration areas

Abstract Loblolly pine ( Pinus taeda L.) regeneration or establishment impacts a large area over the southern US but few studies have examined the microhabitat relationship of small mammals on young pine stands. We collected over 1600 small mammals on natural and artificial loblolly pine regeneration areas. Twenty-five habitat variables describing cover, forage, and structure were measured or derived at each trap station. We used discriminant function analysis (DFA) to construct microhabitat utilization models for the six most abundant small mammal species common to young loblolly pine regeneration areas including the southern short-tailed shrew ( Blarina carolinensis ), golden mouse ( Ochrotomys nuttalli ), white-footed mouse ( Peromyscus leucopus ), cotton mouse ( P. gossypinus ), harvest mouse ( Reithrodontomys humulis ), and cotton rat ( Sigmodon hispidus ). We compared vegetation characteristics at stations where each species was captured versus stations where it was not captured. Models of species microhabitat associations helped explain observed differences in species succession and abundance. Coarse woody debris (i.e. logs and stumps) was found to be an important microhabitat component for O. nuttalli . Logs and stumps were important to P. gossypinus , P. leucopus and S. hispidus . Shrew capture stations had a significantly taller canopy and significantly greater biomass of vines than did non-shrew captures sites. Golden mouse capture stations had significantly longer logs, shorter distance to nearest log, and lower herbaceous profile diversity. Distance to nearest tree was significantly greater while tree height and vine cover were significantly lower at white-footed mouse capture stations. Cotton mouse microhabitat variables describing woody biomass were greater and stump size, tree height and distance to logs were significantly lower at capture stations. Harvest mice capture stations were characterized as having significantly lower tree height than non-capture stations. Cotton rat microhabitat was characterized by twelve variables but cotton rats were collected almost exclusively on the youngest stands with the greatest grass and herbaceous structure. Numerous variables play an important role in determining habitat quality for the array of small mammal species commonly found in early successional pine habitats in the southeast. Microhabitat models help to explain some of the patterns of species occurrence and succession. While the methods used in this study do not necessarily demonstrate preferred habitat, our results allow identification of areas of use.

Responses of Isolated Wetland Herpetofauna to Upland Forest Management

Measurement of responses of herpetofauna at isolated wetlands in the Coastal Plain of South Carolina to disturbance of adjacent loblolly pine forest. Many species of isolated wetland herpetofauna in the Southeastern Coastal Plain may tolerate some disturbance in adjacent upland stands. Responses of isolated wetland herpetofauna to upland silviculture and the need for adjacent forested buffers likely depend on the specific landscape context in which the wetlands occur and composition of the resident herpetofaunal community.

Pathological potential of intraperitoneal transmitter implants in beavers

Beavers (Castor canadensis) with transmitters implanted free in the peritoneal cavity for a period of 2 weeks to 28 months were examined for pathology due to the implant. Nine of 10 beavers necropsied tolerated the implants with no apparent pathology. After 6 weeks, all implants became encapsulated in tight, necrotic fibrous tissue originating from the omentum. Adhesion between the implant capsule and peritoneal structures occurred in 3 animals, with 1 dying from intestinal obstruction. J. WILDL. MANAGE. 51(3):605-606 Implantation of transmitters for biotelemetry is a relatively new advancement in the study of wild, free-ranging animals (Smith and Whitney 1977). Implantable transmitters circumvent attachment problems associated with collars or harnesses on animals with streamlined body form or aquatic habits (Melquist and Hornocker 1979, Davis 1984) and prevent behavioral modification due to the presence of an external radio pack (Korschgen et al. 1984). Despite the effects of anesthesia and surgery and the stress of handling and recovery, little information has been reported on the potential pathological effects of transmitter implants (Guynn et al. 1986). This paper reports on intraperitoneally implanted transmitters in beaver.

Nest characteristics of sympatric populations of fox and gray squirrels

Interspecific competition for nesting cavities between fox squirrels (Sciurus niger) and gray squirrels (S. carolinensis) may occur, but information concerning nest site selection in sympatric populations is unavailable. Thus, we examined seasonal characteristics of nests and nesting sites selected by fox and gray squirrels in central Georgia during 1989-90. We used radio-collared squirrels to locate 367 nests. Fox and gray squirrel use of cavities was greatest (P < 0.05) in fall and winter and in winter, respectively. Gray squirrels used cavities more often (P < 0,05) than did fox squirrels in all seasons. Fox squirrel leaf nests were located higher (P < 0.001) and in trees with larger diameters (P < 0.001) than were gray squirrel leaf nests. There were no differences in diameter at breast height (dbh) (P = 0.54), nest height (P = 0.11), or tree height (P = 0.19) of cavity trees used by fox and gray squirrels. Nest height and vines present in the crown aided in discriminating between leaf nests of fox and gray squirrels. Fox and gray squirrels constructed leaf nests in pines (Pinus spp.) and oaks (Quercus spp.), respectively, more (P < 0.05) than expected on the basis of availability. Because of differences in nest selection between fox and gray squirrels, the potential for nest site overlap is reduced

Herpetofaunal and vegetational characterization of a thermally-impacted stream at the beginning of restoration

Abstract Pen Branch, a third order stream on the Savannah River Site (SRS), located near Aiken, SC, USA, received thermal effluents from the cooling system of a nuclear production reactor from 1954 to 1988. The thermal effluent and increased flow destroyed vegetation in the stream corridor (i.e. impacted portion of the floodplain), and subsequent erosion created a braided stream system with a greatly expanded delta. Restoration of the area began with planting of bottomland hardwood species in 1993. Occurrence of amphibians and reptiles was monitored by daily sampling from 1 January 1995 through 30 September 1996 to characterize the course of the restoration. Vegetation was sampled in the summer of 1996 to characterize the habitats in the unimpacted riparian zone and the impacted stream corridor. A total of 12 580 individuals representing 72 species of herpetofauna were captured. There were no significant differences in relative abundance or diversity of herpetofauna in unplanted versus planted zones within the impacted corridor 3 years after planting. Likewise, there were no significant differences in abundance or diversity of herpetofauna in the upper and lower corridor areas, which differed in site preparation before planting, or in riparian zones of different widths. However, species diversity of amphibians and reptiles in the unimpacted riparian zone was significantly higher than on vegetated islands located between stream braids within the impacted floodplain corridor. There were also significantly more species and individuals within the riparian zone than in the corridor, and the species assemblage within the riparian zone differed from that of the corridor. Woody vegetation within the unimpacted riparian zone was significantly higher in basal area than on islands within the corridor.

Seasonal Mast Availability for Wildlife in the Piedmont Region of Georgia

1990), however, argued that the combination of all other mast-producing species is of equal or greater importance than oak to both game and nongame wildlife. This conclusion was reached because oak and hickory mast is usually available only in fall and winter, and annual yields vary widely. We measured mast production by traditional and buffer species for 2 years on the Piedmont National Wildlife Refuge in Georgia. Our objectives were to determine how these two types varied on a seasonal, a n n u a l , a n d h a b i t a t b a s i s . Mast from buffer species was more frequent a n d d i v e r s e t h a n t h a t f r o m t r a d i t i o n a l m a s t p r o d u c e r s . O u r f i n d i n g s s u g g e s t t h a t a l t h o u g h t r a d i t i o n a l m a s t s p e c i e s a r e i m p o r t a n t , b u f f e r species may play an equally important seasonal role in maintaining a n n u a l d i v e r s i t y .