Flying Squirrel Glaucomys Volans Research Articles

Detection of Porphyrins in Hair Using Capillary Liquid Chromatography-Mass Spectrometry.

Unlike humans, some animals have evolved a physiological ability to deposit porphyrins, which are pigments produced during heme synthesis in cells, in the skin and associated integument such as hair. Given the inert nature and easiness of collection of hair, animals that present porphyrin-based pigmentation constitute unique models for porphyrin analysis in biological samples. Here we present the development of a simple, rapid, and efficient analytical method for four natural porphyrins (uroporphyrin I, coproporphyrin I, coproporphyrin III and protoporphyrin IX) in the Southern flying squirrel Glaucomys volans, a mammal with hair that fluoresces and that we suspected has porphyrin-based pigmentation. The method is based on capillary liquid chromatography-mass spectrometry (CLC-MS), after an extraction procedure with formic acid and acetonitrile. The resulting limits of detection (LOD) and quantification (LOQ) were 0.006–0.199 and 0.021–0.665 µg mL−1, respectively. This approach enabled us to quantify porphyrins in flying squirrel hairs at concentrations of 3.6–353.2 µg g−1 with 86.4–98.6% extraction yields. This method provides higher simplicity, precision, selectivity, and sensitivity than other methods used to date, presenting the potential to become the standard technique for porphyrin analysis.

Ultrasonic Acoustic Surveys of State Endangered Northern Flying Squirrels in the Pocono Mountains, Pennsylvania

AbstractSurveying for flying squirrels by using traditional techniques produces extremely low detection rates compared with ultrasonic acoustics. Within Pennsylvania, the northern flying squirrel subspecies Glaucomys sabrinus macrotis is state listed as endangered due to habitat loss and parasite-mediated competition by and hybridization with the southern flying squirrel Glaucomys volans. This subspecies is isolated from adjacent populations in West Virginia and New York and has experienced drastic population declines. The discovery and characterization of ultrasonic vocalizations of G. s. macrotis and G. volans, as well as successful field surveys with ultrasonic acoustic detectors in the southern Appalachian Mountains, highlight the potential use of this technique for determining the presence of G. s. macrotis. To confirm the feasibility of using this technique on declining populations of G. s. macrotis sympatric with G. volans, we conducted 108 nights of passive ultrasonic acoustic surveys for G. s. macrotis at six survey sites by using two detectors per survey site (N = 12 detectors) in June 2017. We considered sites high quality (“high”) or low quality (“low”) based on the number of physical capture records during the past 2 decades and the dominance of boreo-montane conifer tree species in the overstory. We detected G. s. macrotis at four study sites and G. volans at all six study sites. We found higher average probability of detection for G. s. macrotis in high vs. low sites (0.28 ± 0.06 [mean ± SE] and 0.09 ± 0.07, respectively), whereas probability of detection was similar for G. volans between high and low sites (0.13 ± 0.05 and 0.17 ± 0.05, respectively). We also found G. s. macrotis had lower latency of detection at high vs. low sites (2.7 ± 0.8 and 7.83 ± 1.5 nights, respectively) but G. volans did not vary in latency of detection between sites (5 ± 1.6 and 3.8 ± 1.5 nights, respectively). Our study shows acoustics can be successfully used to efficiently survey G. s. macrotis in Pennsylvania, where populations are small and monitoring these populations more effectively is critical to determining changes in persistence due to climate- and disease-induced factors.

Management Techniques to Stimulate Oak Reproduction in Midwestern Oak Savanna Landscapes

Oak reproduction is often scarce or lacking in oak savannas under ecological restoration management, despite the fact that large canopy gaps created by the removal of invasive brush allow abundant sunlight to reach the ground surface. I conducted two experiments to investigate the effect of manipulating surface vegetation on the acorn-caching behavior of squirrels (gray squirrel Sciurus carolinensis; fox squirrel S. niger; or southern flying squirrel Glaucomys volans) and blue jays (Cyanocitta cristata). In Experiment 1, I created 10 × 10 m bare-ground patches prior to the time of acorn dispersal in restored white oak (Quercus alba) savanna and in adjacent unrestored brushy oak woods. I then compared oak seedling establishment in these bare patches the following summer to seedling establishment in unaltered tall vegetation. In Experiment 2, I used a combination of late-summer burning, tilling with an agricultural disc, and applying herbicide to create bare-ground patches adjacent to established oak woods, and then compared oak seedling establishment in these areas the following summer to that in burn-only, mow-only, and unaltered vegetation. In both experiments, oak seedling establishment was greater in areas denuded of ground vegetation. This agrees with previous research, which concluded that blue jays have a preference for storing acorns in areas of low to bare surface vegetation.

Dietary Resource Preference of the Southern Flying Squirrel (Glaucomys volans)

Abstract There is a paucity of information regarding the feeding habits of the Southern flying squirrel Glaucomys volans. We investigated dietary preference of G. volans by computing the mean daily rate of ingested energy for five food resources: fruits of flowering dogwood Cornus florida; acorns of white oak Quercus alba, water oak Q. nigra, and black oak Q. velutina; and nuts of pignut hickory Carya glabra. The preferred food of G. volans was Q. alba, constituting 49.7% of their mean daily diet. Q. velutina and Q. nigra were ranked next in dietary preference. The least preferred food types were the fruits of C. florida, and nuts of C. glabra. There was no significant difference when comparing sex with food preference and sex with caloric intake.

Morphology, locomotor behaviour and microhabitat use in North American squirrels

AbstractThe rodent family Sciuridae (squirrels) presents an ideal system for examining the morphological, behavioural and ecological correlates of locomotor novelty. Ancestrally, sciurids were arboreal, a condition retained by modern tree squirrels. Two major transitions from the arboreal condition are hypothesized to have occurred in the sciurid clade: (1) flying squirrels evolved gliding from arboreal leaping (parachuting) and (2) chipmunks and ground squirrels became semiarboreal/terrestrial. This study examines morphology, locomotor behaviour and microhabitat use under controlled laboratory conditions in three North American sciurids: eastern chipmunkTamias striatus, red squirrelTamiasciurus hudsonicusand southern flying squirrelGlaucomys volans. Multivariate space was defined using a series of morphological measurements and by continuously sampling individuals moving under identical conditions in a naturalistic enclosure, controlling for the proximate effects of microhabitat structure. Morphospace was characterized by a contrast between proximal and distal limb elements – flying squirrels exhibited elongated forelimbs and shanks and shortened forefeet and hindfeet, while chipmunks exhibited the opposite pattern. Ethospace was characterized by a contrast between aerial locomotion in flying squirrels and ground‐based locomotion in chipmunks. In both instances, red squirrels occupied intermediate positions, as predicted on the basis of retention of ancestral features. Despite significant differences among species at morphological and behavioural levels, ecospace was characterized by overlap between flying squirrels and red squirrels in the use of high supports, and between flying squirrels and chipmunks in the use of large‐diameter supports. The lack of concordance at the ecological level underscores the difficulty in making predictions based solely upon organismal design.

Maximizing survivorship in cold: thermogenic profiles of non-hibernating mammals

Winter-active small mammals residing in seasonal environments employ many different behavioral, anatomical and physiological mechanisms to cope with cold. Herein we review research on survival mechanisms in cold employed by small mammals with emphasis on the families Soricidae, Muridae and Sciuridae. The focus of this review is on research delineating the role of seasonal changes in resting metabolic rate (RMR), nonshivering thermogenesis (NST), body mass, and communal nesting in enhancing winter survivorship of six species of small mammals (masked shrewSorex cinereus, short-tailed shrewBlarina brevicauda, southern red-backed voleClethrionomys gapperi, white-footed mousePeromyscus leucopus, deer mouseP. maniculatus, and southern flying squirrelGlaucomys volans) residing in the Appalachian Mountains of Pennsylvania, USA. Each species shows good over-winter survivorship but exhibits a different suite of mechanisms to maximize survival in cold.B. brevicauda, S. cinereus, andG. volans show slight increases in RMR during winter, whereasPeromyscus andC. gapperi exhibit decreased RMR overwinter. All six species experience elevated NST in winter. The comparatively low RMR and NST ofG. volans during winter was attributable to a decreased energy expenditure due to a larger body mass, coupled with communal nesting in cavities of trees that provided insulation from low ambient temperatures. Squirrels nesting singly experienced a longer period of elevated NST in winter and higher mean NST year-round than did squirrels nesting communally. Energy conservation in the form of growth retardation in winter was exhibited byC. gapperi andS. cinereus but not the other species.

Homing in and Ecology of the Southern Flying Squirrel Glaucomys volans in Southeastern Virginia

A population of the southern flying squirrel Glaucomys volans in southeastern Virginia was examined for its homing ability. Nest boxes were used to capture the experimental animals and to evaluate homing. Squirrels returned home with high frequency from distances up to 1000 m. There was a significant association between low temperature and large aggregations of huddling squirrels in nest boxes. Holes used as feeding stations were never converted to primary nests.

Population Dynamics and Coevolution of Adult Siphonapteran Parasites of the Southern Flying Squirrel (Glaucomys volans volans)

One possible outcome of the competitive interaction of two or more species for a limited resource is the development of one or more strategies which allow all of the species involved to use the resource that is limiting. This study suggests that four species of fleas which inhabit the nest of the southern flying squirrel (Glaucomys volans volans) have coevolved life history strategies which allow them to cycle asynchronously. By being in the adult stage during different months of the year the four flea species apparently do not place undue parasitic pressure on the host squirrels. INTRODUCTION Whenever two or more sympatric species require the same habitat, the same food source, and the resource is in short supply competition will result. As a group, fleas have three major mechanisms to avoid interspecific competition. Some species sEparate spatially while feeding on the host. Prasad (1972) showed that two rat fleas, Xenopsylla cheopis and Xenopsylla astia, prefer different feeding sites on the host rats with X. astia feeding only on the anterior half of the host, mainly on the neck, and X. cheopis feeding only on the posterior portions. A second mechanism is extremely sensitive microhabitat selection. Benton (1972) noted several species in which the external environment surrounding the host and its nest is as important as the host itself. George (1959) found that the microenvironment within the nest of the pied flycatcher, Muscicapa hypoleuca, as determined by the compass direction in which the nest hole faced, determined the overall numbers of the different species of fleas present in any given nest. Third, fleas may separate temporally. Abreu (in press) has shown this in fleas of the European rabbit, Oryctolagus cuniculus, in Portugal. We suggest that this mechanism has been developed by nest fleas which infest the southern flying squirrel Glaucomys volans volans (Linnaeus). Preliminary studies (K. Baker and M. Prusak, pers. comm.) indicated the existence of a temporal separating mechanism used by four species of siphonapteran nest parasites infesting the nest of the southern flying squirrel. Glaucomys v. volans acts as a primary host for four species of fleas in the northeastern United States (Benton and Cerwonka, 1960; Main, 1970; Miller and Benton, 1973; Benton and Kelly, 1975; Conorhinopsylla stanfordi Stewart, Epitedia faceta (Rothschild), Opisodasys pseudarctomys (Baker), and Orchopeas howardii howardii (Baker). All four are primarily nest fleas but can also be taken from the host. Nest fleas are extremely specialized in terms of habitat use. They usually require a blood meal from a mammal present in the nest in order to lay fertile eggs and they are very often quite host-specific. The fleas also require a suitable nest in which to complete the four stages of their development. It is therefore possible that different species of fleas infesting the same host and host nest would come under intense interspecific competition in both the larval and adult stages, and this competition could lead to temporal species separation. 1 Parts of this material were presented at the First International Conference on Fleas, Ashton, England, June, 1977. 2 Present address: Department of Entomology, University of Massachusetts, Amherst, MA 01003.