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Articles 1 - 30 of 115
Full-Text Articles in Zoology
The Effects Of Chemical Secretions By Millipedes On Anting Behaviour In Birds And Other Animals, Theo Fraser
The Effects Of Chemical Secretions By Millipedes On Anting Behaviour In Birds And Other Animals, Theo Fraser
2023 REYES Proceedings
Birds perform a behavior known as anting in which they actively rub ants in their feathers or allow ants to crawl over their bodies. Several hypotheses have been proposed to explain this behavior, but no one hypothesis can account for all cases of anting that have been observed. Anting behavior has been recorded in species other than birds including primates, and substances other than ants such as millipedes may be used. This paper explores the use of millipedes in anting by birds, capuchin monkeys and lemurs. The three hypotheses supported by these studies include 1) anting serves as food preparation …
Hypotheses Related To Anting By Birds, Helena Flores
Hypotheses Related To Anting By Birds, Helena Flores
2023 REYES Proceedings
“Anting” is a widespread behavior among bird species and mammals. Due to the various characteristics of this behavior, numerous hypotheses have been proposed to explain it. This behavior can be classified as “active”, in which birds take a bill full of ants and rub them into their feathers, or “passive” when birds let ants wander through their plumage. The hypotheses state that anting may be performed as an (1) antiparasitic behavior, for (2) feather grooming, as a way of (3) food preparation or to (4) decrease skin irritation during molt, even as a (5) sensory stimulation tool. This review compiles …
Nestedness And Modularity Of Avian Metacommunities Across Gradients Of Chesapeake Bay Island Characteristics, Grant Walter Bowers
Nestedness And Modularity Of Avian Metacommunities Across Gradients Of Chesapeake Bay Island Characteristics, Grant Walter Bowers
Biological Sciences Theses & Dissertations
Islands are not only great models for understanding the ways in which communities are linked by the dispersal of their members to form metacommunities, but are of particular interest to conservationists. One important aspect of metacommunity structure is the degree of nestedness—whether or not less speciose communities are perfect subsets of more speciose communities. Another important metric of metacommunity structure is modularity—the degree to which communities belong to modules composed of other communities that share the same species but have little species overlap with communities from different modules. Environmental gradients have received insufficient attention as predictors of metacommunity nestedness and …
Temporal Dynamics And Seed Dispersal In Plant-Frugivore Communities Of The Dominican Republic, Spencer Christian Schubert
Temporal Dynamics And Seed Dispersal In Plant-Frugivore Communities Of The Dominican Republic, Spencer Christian Schubert
Biological Sciences Theses & Dissertations
Plant-animal mutualisms are a foundational component of biodiversity in terrestrial ecosystems. Most tropical forest plants have adapted to produce fleshy fruits to attract frugivorous animals to disperse seeds. Interaction patterns among plant taxa and their seed dispersers are driven by a complex suite of factors involving their evolutionary history and environmental context, and the structure of these mutualistic networks are theoretically tied to their ecological function. I carried out a series of field studies to investigate the temporal dynamics of mutualistic interactions of plant and avian frugivore communities in the central Dominican Republic and how their characteristics affect seed dispersal …
Monitoring Extinction Risk And Threats Of The World's Fishes Based On The Sampled Red List Index, Rafael Miranda, Imanol Miqueleiz, William Darwall, Catherine Sayer, Nicholas K. Dulvy, Kent E. Carpenter, Beth Polidoro, Nadia Dewhurst-Richman, Caroline Pollock, Craig Hilton-Taylor, Robin Freeman, Ben Collen, Monika Böhm
Monitoring Extinction Risk And Threats Of The World's Fishes Based On The Sampled Red List Index, Rafael Miranda, Imanol Miqueleiz, William Darwall, Catherine Sayer, Nicholas K. Dulvy, Kent E. Carpenter, Beth Polidoro, Nadia Dewhurst-Richman, Caroline Pollock, Craig Hilton-Taylor, Robin Freeman, Ben Collen, Monika Böhm
Biological Sciences Faculty Publications
Global biodiversitytargets require us to identify species at risk of extinction and quantify status and trends of biodiversity. The Red List Index (RLI) tracks trends in the conservation status of entire species groups over time by monitoring changes in categories assigned to species. Here, we calculate this index for the world’s fishes in 2010, using a sampled approach to the RLI based on a randomly selected sample of 1,500 species, and also present RLI splits for freshwater and marine systems separately. We further compare specific traits of a worldwide fish list to our sample to assess its representativeness. Overall, 15.1% …
The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David
The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David
Biological Sciences Faculty Publications
Many wildlife species are live captured, sampled, and released; for polar bears (Ursus maritimus) capture often requires chemical immobilization via helicopter darting. Polar bears reduce their activity for approximately 4 days after capture, likely reflecting stress recovery. To better understand this stress, we quantified polar bear activity (via collar‐mounted accelerometers) and body temperature (via loggers in the body core [Tabd] and periphery [Tper]) during 2–6 months of natural behavior, and during helicopter recapture and immobilization. Recapture induced bouts of peak activity higher than those that occurred during natural behavior for 2 of 5 bears, …
Significance Of Autumn And Winter Food Consumption For Reproduction By Southern Beaufort Sea Polar Bears, Ursus Maritimus, Blaine D. Griffen, John P. Whiteman, Sariah Pullan
Significance Of Autumn And Winter Food Consumption For Reproduction By Southern Beaufort Sea Polar Bears, Ursus Maritimus, Blaine D. Griffen, John P. Whiteman, Sariah Pullan
Biological Sciences Faculty Publications
Polar bears (Ursus maritimus) in the southern Beaufort Sea experience long annual periods when preferred seal prey are scarce or are unavailable. Consumption of bowhead whale (Balaena mysticetus) carcasses from native Alaskan subsistence hunting is increasingly common for onshore polar bears, yet the energetic consequences of this consumption remain unclear. We use data on bears captured repeatedly over periods that encompassed autumn and winter, combined with calculations, to show that adult female bears likely consume an average of at least 4 seal equivalents during both autumn and winter periods and that considerable variation in energy intake …
Imaging Technologies Build Capacity And Accessibility In Phytoplankton Species Identification Expertise For Research And Monitoring: Lessons Learned During The Covid-19 Pandemic, Sophie Clayton, Leah Gibala-Smith, Kathryn Mogatas, Chanel Flores-Vargas, Kayla Marciniak, Maci Wigginton, Margaret R. Mulholland
Imaging Technologies Build Capacity And Accessibility In Phytoplankton Species Identification Expertise For Research And Monitoring: Lessons Learned During The Covid-19 Pandemic, Sophie Clayton, Leah Gibala-Smith, Kathryn Mogatas, Chanel Flores-Vargas, Kayla Marciniak, Maci Wigginton, Margaret R. Mulholland
OES Faculty Publications
As primary producers, phytoplankton play an integral role in global biogeochemical cycles through their production of oxygen and fixation of carbon. They also provide significant ecosystem services, by supporting secondary production and fisheries. Phytoplankton biomass and diversity have been identified by the Global Ocean Observing System (GOOS) as Essential Ocean Variables (EOVs), properties that need to be monitored to better understand and predict the ocean system. Phytoplankton identification and enumeration relies on the skills and expertise of highly trained taxonomic analysts. The training of new taxonomic analysts is intensive and requires months to years of supervised training before an analyst …
Habitat Partitioning And Associated Morphological Differences Among Three Species Of Catostomidae (Teleostei: Actinopterygii) In The South Fork Roanoke River, Virginia, Steven L. Powers, Dakota R. Spruill
Habitat Partitioning And Associated Morphological Differences Among Three Species Of Catostomidae (Teleostei: Actinopterygii) In The South Fork Roanoke River, Virginia, Steven L. Powers, Dakota R. Spruill
Virginia Journal of Science
The upper Roanoke River has 11 species of Catostomidae including Thoburnia rhothoeca, Torrent Sucker; Moxostoma cervinum, Blacktip Jumprock; and Moxostoma ariommum, Bigeye Jumprock. Resource partitioning appears to be a key component of maintaining diverse fish assemblages with habitat and food partitioning cited as especially important in communities containing members of the same family. The diets of these species have been documented in previous work revealing only modest differences among them. Snorkeling observations and subsequent quantification of microhabitat were conducted to illuminate habitat partitioning among these morphologically and ecologically similar species. Thoburnia rhothoeca inhabited the shallowest, fastest water, over the …
Population Dynamics And Dispersal Coalitions In The Cooperatively Breeding Acorn Woodpecker, Natasha Hagemeyer
Population Dynamics And Dispersal Coalitions In The Cooperatively Breeding Acorn Woodpecker, Natasha Hagemeyer
Biological Sciences Theses & Dissertations
Dispersal is a critical life-stage with consequences not only for the individual, but for population dynamics and thus the fate of the whole species. The creation of dispersal coalitions can lead to complex outcomes and affect how changes in abundance occur on the landscape. I examined population dynamics and dispersal coalitions in a population of cooperatively breeding acorn woodpeckers in central California, USA. Using a 34-year dataset on occupancy and abundance, I determined that increases in abundance were determined by dispersal to new locations. This resulted in increased occupancy, rather than increases in group size and larger coalitions. I then …
Global Extinction Risk For Seahorses, Pipefishes And Their Near Relatives (Syngnathiformes), Riley A. Pollom, Gina M. Ralph, Caroline M. Pollock, Amanda C.J. Vincent
Global Extinction Risk For Seahorses, Pipefishes And Their Near Relatives (Syngnathiformes), Riley A. Pollom, Gina M. Ralph, Caroline M. Pollock, Amanda C.J. Vincent
Biological Sciences Faculty Publications
Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are …
Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby
Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby
Biological Sciences Faculty Publications
Ocean acidification (OA) is negatively affecting calcification in a wide variety of marine organisms. These effects are acute for many tropical scleractinian corals under short-term experimental conditions, but it is unclear how these effects interact with ecological processes, such as competition for space, to impact coral communities over multiple years. This study sought to test the use of individual-based models (IBMs) as a tool to scale up the effects of OA recorded in short-term studies to community-scale impacts, combining data from field surveys and mesocosm experiments to parameterize an IBM of coral community recovery on the fore reef of Moorea, …
Olfactory Behavioral Responses Of Mosquito Vectors To Select Attractants And Floral Scents As Related To Circadian Rhythms And Photoperiod Regimes, Bernadette A. Ferraro
Olfactory Behavioral Responses Of Mosquito Vectors To Select Attractants And Floral Scents As Related To Circadian Rhythms And Photoperiod Regimes, Bernadette A. Ferraro
Biomedical Sciences Theses & Dissertations
This dissertation discusses mosquito behavioral activities involving circadian rhythms defined as insect sensitivity to select of chemical volatiles that vary throughout the 24-hour day. Circannual rhythms occur over seasons varying in photoperiod, defined as the seasonal cycle of light and darkness. These cycles can be endogenously controlled by circadian clocks. The impetus for this research was initiated when reading about the neglected temporal dimension in the context of insect chemical ecology, including insect olfaction. It was proposed that sensitivity to odors does not change in general, but specific sensitivities could vary according to time of day. Chemical scents emitted by …
The Natural History Of The Marsh Rice Rat, Oryzomys Palustris, In Eastern Virginia, Robert K. Rose
The Natural History Of The Marsh Rice Rat, Oryzomys Palustris, In Eastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The marsh rice rat, Oryzomys palustris, is a common rodent in tidal marshes of eastern Virginia, including those on the barrier islands. It also is present in grassy old fields in upland habitats in the coastal plain and parts of the piedmont of Virginia. This report summarizes what has been learned in recent decades about the population biology of this species in Virginia, including aspects of behavior, density, diet, distribution, genetics, habitats, mammal associates, and reproduction.
Granulosa Cell Proliferation Is Inhibited By Pge2 In The Primate Ovulatory Follicle, Patric S. Lundberg, Gil J. Moskowitz, Carmel Bellacose, Esra Demirel, Heidi A. Trau, Diane M. Duffy
Granulosa Cell Proliferation Is Inhibited By Pge2 In The Primate Ovulatory Follicle, Patric S. Lundberg, Gil J. Moskowitz, Carmel Bellacose, Esra Demirel, Heidi A. Trau, Diane M. Duffy
Computer Science Faculty Publications
Prostaglandin E2 (PGE2) is a key paracrine mediator of ovulation. Few specific PGE2-regulated gene products have been identified, so we hypothesized that PGE2 may regulate the expression and/or activity of a network of proteins to promote ovulation. To test this concept, Ingenuity Pathway Analysis (IPA) was used to predict PGE2-regulated functionalities in the primate ovulatory follicle. Cynomolgus macaques underwent ovarian stimulation. Follicular granulosa cells were obtained before (0 h) or 36 h after an ovulatory dose of human chorionic gonadotropin (hCG), with ovulation anticipated 37-40 h after hCG. Granulosa cells were obtained from additional monkeys 36 h after treatment with …
Insights Into The Feeding Behaviors And Biomechanics Of Varroa Destructor Mites On Honey Bee Pupae Using Electropenetrography And Histology, Andrew Y. Li, Steven C. Cook, Daniel E. Sonenshine, Francisco Pasada-Florez, Noble I.I. Noble, Joseph Mowery, Conner J. Gulbronson, Gary R. Bauchan
Insights Into The Feeding Behaviors And Biomechanics Of Varroa Destructor Mites On Honey Bee Pupae Using Electropenetrography And Histology, Andrew Y. Li, Steven C. Cook, Daniel E. Sonenshine, Francisco Pasada-Florez, Noble I.I. Noble, Joseph Mowery, Conner J. Gulbronson, Gary R. Bauchan
Biological Sciences Faculty Publications
Feeding behaviors and biomechanics of female Varroa destructor mites are revealed from AC-DC electropenetrography (EPG) recordings of mites feeding from Apis mellifera honey bee pupae and histology of mite internal ingestion apparatus. EPG signals characteristic of arthropod suction feeding (ingestion) were identified for mites that fed on pupae during overnight recordings. Ingestion by these mites was confirmed afterwards by observing internally fluorescent microbeads previously injected into their hosts. Micrographs of internal ingestion apparatus illustrate the connection between a gnathosomal tube and a pharyngeal lumen, which is surrounded by alternating dilator and constrictor muscles. Inspection of EPG signals showed the muscularized …
Microhabitat Comparison Of Percina Roanoka (Roanoke Darter) And Percina Nevisense (Chainback Darter) In The Roanoke River, Dakota R. Spruill, Steven L. Powers
Microhabitat Comparison Of Percina Roanoka (Roanoke Darter) And Percina Nevisense (Chainback Darter) In The Roanoke River, Dakota R. Spruill, Steven L. Powers
Virginia Journal of Science
Snorkel observations of Percina roanoka and P. nevisense in the Roanoke River during summer months were followed by measuring current velocity, water depth, and substrate diameter at points of occupation. A total of 89 observations of P. roanoka and 81 observations of P. nevisense were compared using two-sample T-tests. Percina roanoka inhabited faster, shallower water than P. nevisense with the former found in a mean flow of 0.318 m/s and depth of 31.53 cm and the latter in a mean flow of 0.17 m/s and depth of 55.6 cm. Mean diameter of substrate at points of occupation did not differ …
Natural History Of The Eastern Harvest Mouse In Southeastern Virginia, Robert K. Rose
Natural History Of The Eastern Harvest Mouse In Southeastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The Eastern Harvest Mouse, Reithrodontomys humulis, has been studied extensively in southeastern Virginia since 1979, using a combination of live and pitfall trapping methods. This smallest rodent of eastern North America also is one of most versatile, occupying a range of habitats in southeastern Virginia from old fields in different stages of succession, brushy edges, and forests of different types. As with other species of Reithrodontomys, R. humulis often is associated with the Hispid Cotton Rat, Sigmodon hispidus, with both reaching modest densities in old fields. Two capture-mark-release studies of small mammal communities in southern Chesapeake lasting …
Compositional Changes In Two Small Mammal Communities During Succession In Southeastern Virginia, Robert K. Rose, Robyn M. Nadolny, Jay Kiser, Stephen E. Rice, Heather Green Salamone, Jana Eggleston, Holly D. Gaff
Compositional Changes In Two Small Mammal Communities During Succession In Southeastern Virginia, Robert K. Rose, Robyn M. Nadolny, Jay Kiser, Stephen E. Rice, Heather Green Salamone, Jana Eggleston, Holly D. Gaff
Virginia Journal of Science
Changes in the composition of two small mammal communities were studied during 8 and 9 years of ecological succession in southern Chesapeake. Virginia. Using monthly live-trapping on grids of similar size and history since their abandonment as agricultural fields, we learned that house mice were early colonists on one grid but not the other. Two species of herbivorous rodent and the granivorous eastern harvest mouse were numerically dominant on both grids across the study. Some species disappeared early on one grid but persisted to the end at the other. The two arboreal small mammals, golden and white-footed mice, were most …
Natural History Of The Southern Bog Lemming In Southeastern Virginia, Robert K. Rose
Natural History Of The Southern Bog Lemming In Southeastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The isolated subspecies of Southern Bog Lemming of southeastern Virginia, Synaptomys cooperi helaletes, has been studied extensively since its "rediscovery" in the Great Dismal Swamp in 1980. Multiple studies using pitfall traps, starting in the Great Dismal Swamp National Wildlife Refuge and then extending elsewhere in southeastern Virginia and adjacent northeastern North Carolina, have revealed lemmings to be much more widespread and often more common than previously believed, with their presence now confirmed as far west as Surry and Sussex counties, about 30 km east of Petersburg, Virginia. When present, lemmings often are among the most numerous members of …
Do Avian Blood Parasites Influence Hypoxia Physiology In A High Elevation Environment?, Farah Ishtiaq, Sahas Barve
Do Avian Blood Parasites Influence Hypoxia Physiology In A High Elevation Environment?, Farah Ishtiaq, Sahas Barve
Biological Sciences Faculty Publications
BACKGROUND: Montane birds which engage in elevational movements have evolved to cope with fluctuations in environmental hypoxia, through changes in physiological parameters associated with blood oxygen-carrying capacity such as haemoglobin concentration (Hb) and haematocrit (Hct). In particular, elevational migrants which winter at low elevations, encounter varying intensities of avian haemosporidian parasites as they traverse heterogeneous environments. Whilst high intensity parasite infections lead to anaemia, one can expect that the ability to cope with haemosporidian infections should be a key trait for elevational migrants that must be balanced against reducing the oxygen-carrying capacity of blood in response to high elevation. In …
Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff
Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff
Biological Sciences Faculty Publications
Tick population control technologies have been studied for several decades but no method is successful in all situations. The success of each technology depends on tick species identity and abundance, host species identity and abundance, phenology of both ticks and hosts, geographic region, and a multitude of other factors. Here we review current technologies, presenting an overview of each and its effect on three common tick species in the eastern United States: blacklegged ticks (Ixodes scapularis (Say; Ixodida: Ixodidae)), lone star ticks (Amblyomma americanum (Linnaeus; Ixodida: Ixodidae)), and American dog ticks (Dermacentor variabilis (Say; Ixodida: Ixodidae)). Moreover, …
Predation On Artificial Turkey Nests At Radford Army Ammunition Plant In Western Virginia, Shane Brandes, Karen E. Powers, Len L. Diioia Jr.
Predation On Artificial Turkey Nests At Radford Army Ammunition Plant In Western Virginia, Shane Brandes, Karen E. Powers, Len L. Diioia Jr.
Virginia Journal of Science
Because ground-nesting wild turkeys (Meleagris gallopavo) may sustain high incidences of nest predation in western Virginia, determining their predators is essential to understanding risk and managing the birds. Our study investigated potential predators of wild turkey nests at the Radford Army Ammunition Plant, New River Unit (RFAAP; Pulaski Co., in western Virginia). Here, we established 8 artificial nests during the breeding season for wild turkey (March-April, 2017), and documented predators via game cameras. Thirty-one species of mammals and birds visited the nests over the 31-day study. Nest predation was verified 56 times across 6 species, including coyotes ( …
An Erythristic Morph Of Red-Backed Salamander (Plethodon Cinereus) Collected In Virginia, Trevor L. Chapman, Brian G. Gall, Kari L. Spivey
An Erythristic Morph Of Red-Backed Salamander (Plethodon Cinereus) Collected In Virginia, Trevor L. Chapman, Brian G. Gall, Kari L. Spivey
Virginia Journal of Science
Eight different color polymorphisms of the Red-backed Salamander (Plethodon cinereus) have been described throughout its range. Among them, the erythristic phenotype is a mimetic morph with coloration patterns similar to that of toxic Eastern Newt efts (Notophthalmus viridescens). We describe an erythristic morph of P. cinereus collected at Mountain Lake Biological Station, Virginia. To our knowledge, there are no prior published records of this morph in Virginia.
Reproductive Competency And Mitochondrial Variation In Aged Syrian Hamster Oocytes, Fang Li, Frank J. Castora, Wentia Ford, Khalid Alarid, Howard W. Jones Jr., R. James Swanson
Reproductive Competency And Mitochondrial Variation In Aged Syrian Hamster Oocytes, Fang Li, Frank J. Castora, Wentia Ford, Khalid Alarid, Howard W. Jones Jr., R. James Swanson
Biological Sciences Faculty Publications
The hamster is a useful model of human reproductive biology because its oocytes are similar to those in humans in terms of size and structural stability. In the present study we evaluated fecundity rate, ovarian follicular numbers, ova production, mitochondrial number, structure and function, and cytoplasmic lamellae (CL) in young (2–4 months) and old (12–18 months) Syrian hamsters (Mesocricetus auratus). Young hamsters had higher fertilisation rates and larger litters than old hamsters (100 vs 50% and 9.3 +/- 0.6 vs 5.5 +/- 0.6, respectively). Ovarian tissue from superovulated animals showed a 46% decrease in preantral follicles in old …
Testing Alternative Hypotheses For The Cause Of Population Declines: The Case Of The Red-Headed Woodpecker, Walter D. Koenig, Eric L. Walters, Paul G. Rodewald
Testing Alternative Hypotheses For The Cause Of Population Declines: The Case Of The Red-Headed Woodpecker, Walter D. Koenig, Eric L. Walters, Paul G. Rodewald
Biological Sciences Faculty Publications
The Red-headed Woodpecker (Melanerpes erythrocephalus) has experienced strong population declines during the past 3 decades. Using North American Breeding Bird Survey (BBS) and Audubon Christmas Bird Count (CBC) data, we investigated 4 hypotheses that may explain this decline, including: (1) interspecific competition with native Red-bellied Woodpeckers (Melanerpes carolinus) and nonnative European Starlings (Sturnus vulgaris); (2) predation by Cooper's Hawks (Accipiter cooperii) and Sharp-shinned Hawks (Accipiter striatus); (3) climate change; and (4) changes in forested area within their range. In analyses of both the breeding and overwintering periods, our results indicated …
The Small Mammals Of Southeastern Virginia As Revealed By Pitfall Trapping, Robert K. Rose
The Small Mammals Of Southeastern Virginia As Revealed By Pitfall Trapping, Robert K. Rose
Biological Sciences Faculty Publications
Pitfall trapping is a poor method to catch small mammals but the only way to catch and study the Southeastern Shrew (Sorex longirostris), the primary mammal of interest in the field studies reported here. While learning much about its distribution and abundance, still more was learned about the other small mammals present in forests and fields of eastern Virginia. A total of 15 species was captured at 19 locations during the 1990-2013 period, including five shrews, two moles, and eight rodents, representing all but one of the common small mammals in eastern Virginia.
Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky
Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky
Biological Sciences Faculty Publications
During a 17-yr telemetry study, we examined the diet and ambush behavior of a population of Crotalus horridus in southeastern Virginia. Forty dietary items were identified from 37 fecal samples. We documented 722 instances of snakes in an ambush posture, 61 of which were in a vertical-tree posture, as if hunting arboreal prey at the base of a tree. The most common prey items were Eastern Gray Squirrels (Sciurus carolinensis), which accounted for 45 of all dietary items and represented an estimated 78 of total biomass consumed by C. horridus. Prey was not consumed in proportion to availability, …
The Behavioral Causes Of Reproductive Skew In Cooperatively Polygynandrous Acorn Woodpeckers (Melanerpes Formicivorus), Anna C. Brownson
The Behavioral Causes Of Reproductive Skew In Cooperatively Polygynandrous Acorn Woodpeckers (Melanerpes Formicivorus), Anna C. Brownson
Biological Sciences Theses & Dissertations
Reproductive skew, the degree to which reproduction is shared among same-sex individuals in a social group, is a pattern affected by ecological conditions, sociality, cooperation, and the inter- and intrasexual behavior of individuals in complex animal societies. Transactional and compromise skew models assume that high skew is the product of dominance hierarchies among cobreeders, yet this has rarely been tested. Both model types fail to incorporate the decisions of more than two individuals, generally overlooking the effect of female behavior on male reproductive success in multi-male groups, and are ineffective at predicting skew in larger groups characterized by more than …
Friends Or Foes: Interpreting The Relationship Between Two Synoptic Small Mammals In Southeastern Virginia, The Hispid Cotton Rat (Sigmodon Hispidus) And Eastern Harvest Mouse (Reithrodontomys Humulis), Sarah A. Crawford
Biological Sciences Theses & Dissertations
Relatively little is known about the relationship between the hispid cotton rat (Sigmodon hispidus) and the eastern harvest mouse (Reithrodontomys humulis). Literature on these two syntopic genera in other areas of the United States suggests that competition may exist; however, both species seem to be greatly affected by environmental changes, making it difficult to draw any definite conclusions. Live trapping and microhabitat data collected from 2 old fields in Chesapeake, Virginia over a 9-year period were used to assess the biotic and abiotic influences on space use by these two species. Each I-ha plot consisted of 2 live traps placed …