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Rubenstein, David - - 2012
Bond, Bobby - - 2012
In Georgia, there are three distinct populations of black bears (Ursus americanus, including two subspecies americanus and floridanus). The Middle Georgia population has been shown to exhibit high genetic similatities within the population and we wanted to determine if the Ocmulgee River was a barrier to bear movements. One out ...
Wheeldon, Tyler - - 2012
We report on three presumed wolf pups captured in Michigan's northern Lower Peninsula, potentially representing the first documented case of wolf reproduction in the Lower Peninsula since wolves were extirpated there a century ago. The pups, two females and one male, were assumed to be wolves based on physical characteristics. ...
Mangan, Brian - - 2012
Multiple specimens of the rusty crayfish (Orconectes rusticus) collected from the Susquehanna River in Pennsylvania exhibited Rheotanytarsus sp. (Diptera: Chironomidae) living on their carapaces and chelipeds. Although chironomid larvae have been reported as living on many aquatic organisms, this is the first record of chironomids living phoretically on crayfish.
Kisser, Brooke - - 2012
Free-ranging, juvenile thirteen-lined ground squirrels (Ictidomys tridecemlineatus) in southwestern Michigan were fitted in late summer or fall with external skin-temperature loggers. Data were obtained the following spring for five males and three females. During the heterothermal period, all squirrels exhibited 11-29 prolonged ([bar.x] = 9.4 d) torpor bouts punctuated by ...
Lang, Shirley - - 2012
The giant earthworm, Rhinodrilus priollii Righi 1967, is among the largest terrestrial invertebrates known worldwide, reaching lengths >2 m. To investigate the evolutionary history, of the species and aspects of their reproductive biology, we collected R. priollii specimens from several field sites in central Amazonia. Phylogenetic analyses of 16 individuals ...
White, Matthew - - 2012
Walleye from the upper Cumberland River drainage were examined by means of mitochondrial DNA restriction fragment length polymorphism (RFLP) analysis, microsatellite analysis of nuclear DNA, and sequencing of the mitochondrial DNA control region. The objectives of this study were to identify native Eastern Highland and introduced Great Lakes walleye and ...
Becker, Lily J. - - 2012
Male sailfin mollies, Poecilia latipinna, exhibit alternative mating strategies that are correlated with body size. Larger males court females and often prevent smaller males from accessing females, while smaller males often forcefully inseminate females. This pattern is well documented in the laboratory but has not been studied thoroughly in the ...
Pilger, Tyler - - 2012
North American freshwater mussels of the Order Unionoida are critically imperiled, primarily due to stream habitat modifications and fragmentation by reservoirs. Whereas many species respond negatively to impoundments, some species benefit by increases in lentic habitat. During winter drawdown of Tuttle Creek Reservoir, KS in 2006-2007, we collected freshwater mussel ...
Metzke, B.A. - - 2012
Cladoceran community dynamics in limnetic systems often are correlated with temperature patterns. We sought to relate cladoceran temporal patterns and community composition to spatial and temporal temperature patterns in a cooling water reservoir (Newton Lake, Jasper County, Illinois). Effluent released into Newton Lake creates a temperature gradient where portions of ...
Williams, Ernest - - 2012
This study assessed the influence of annual snowpack on long term changes in the predatory regime of four high elevation ponds in the mountains of northwest Wyoming. Over 36 y of observation, in two ponds the primary predator alternated between phantom midge Chaoborus americanus larvae and Diaptomus shoshone predatory copepods, ...
Ehrenfeld, Joan - - 2012
Nitrogen dynamics in wetlands are often assumed to vary with water tables and the resulting patterns of soil moisture, and other soil properties. To test this hypothesis, we have examined N mineralization patterns in two replicate sequences of three forested wetland types located on a shallow water table gradient in ...
McCulley, R.L. - - 2012
Woody plant encroachment and proliferation in grasslands is occurring worldwide and has significant but variable effects on ecosystem processes, including primary production, litter decomposition, and N cycling. In mesic systems, recent reports suggest aboveground net primary production (ANPP) is stimulated by grass-to-woodland conversion; however, significant losses of soil C may ...
Hanberry, Brice - - 2012
The U.S. General Land Office surveys, conducted between the late 1700s to early 1900s, provide records of trees prior to widespread European and American colonial settlement. However, potential and documented surveyor bias raises questions about the reliability of historical tree density estimates and other metrics based on density estimated from ...
Shuey, John - - 2012
Despite immense diversity, insect conservation is typically species specific. Effective insect conservation will require efforts that capture insect species and communities at all levels of biological organization. Surrogate conservation targets, such as habitat based conservation planning tools were designed to capture poorly understood taxa such as invertebrates. We evaluated a ...
Christopher, Cory - - 2012
Litter-dwelling arthropods play crucial roles in litter decomposition and nutrient cycling, and changes in their diversity or abundance can affect these processes. Previous studies have outlined individual effects of invasive plants and overabundant ungulates on litter-dwelling arthropod communities but have paid little attention to whether invasive plants and ungulates interact ...
Urbanek, Rachael - - 2012
Despite the widespread interest in plant community restoration, few studies have assessed white-tailed deer (Odocoileus virginianus Zimm.) herbivory on herbaceous species and even fewer studies have focused on deer herbivory in restored plant communities. During 2007-2009, we investigated the effect of deer density and associated deer browse on two restored ...
Stephens, Elizabeth - - 2012
Knowledge of seed ecology is important for the restoration of ecosystems degraded by anthropogenic activities. Current efforts to preserve and reintroduce populations of plant species endemic to Florida are hindered by a lack of information on demographic responses to human alteration. Comparisons of seed removal, germination, and establishment in both ...
Emery, Sarah - - 2012
Soil biota such as arbuscular mycorrhizal fungi (AMF) have been shown to increase invasive plant species success in a wide variety of systems by providing both direct and indirect benefits to the invader. For example, Centaurea stoebe invasion in the western US is at least partially due to AMF networks ...
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