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McManamay, Ryan - - 2012
In Apr. 2010 white suckers (Catostomus commersoni) were observed spawning in the small tributary to a constructed stormwater pond on the Virginia Polytechnic Institute and State University campus. The tributary is the only direct input to the pond and provides perennial flow. We documented spawning activity, habitat characteristics, habitat use, ...
Cove, Michael - - 2012
The mesopredator release hypothesis (MRH) has been suggested as a reason why many mammalian generalist mesopredators flourish and become abundant. However, the MRH has only been examined in a limited number of field studies. Some studies have argued that coyotes (Canis latrans) act as top predators in fragmented forest systems ...
Hanberry, Brice - - 2012
Fine scale spatial mapping of historical tree records over large extents is important for determining historical species distributions. We compared performance of two ensemble methods based on classification trees, random forests, and boosted classification, for mapping continuous historical distributions of tree species. We used a combination of soil and terrain ...
Redmond, Miranda - - 2012
This study documents 25 y of change in the abundance of Quercus rubra (northern red oak) and Quercus alba (white oak), in a previous chestnut (Castanea castanea)oak forest in the Southern Appalachians of the eastern U.S.A. Spatially explicit data from 1983-1984 and 2007-2008 of individually mapped trees on two plots ...
Chun, Young - - 2012
We investigated the changes in stand structure, species composition, and soil characteristics of jack pine (Pinus banksiana Lamb.) disjunct stands on the southern shore of Lake Michigan in North America. Our NMS (Non-metric Multidimensional Scaling) ordination revealed a chronosequence of the succession from jack pine stand to black oak (Quercus ...
Schroeder, Nathan - - 2012
In tallgrass prairie restoration, dominance by competitive late succession prairie grasses may cause loss of species that are poor competitors. In a field experiment we tested whether disturbance could reverse this process for Liatris scariosa var. nieuwlandii, a threatened savanna species thought to be a poor competitor. At our study ...
Gulezian, Paul - - 2012
Interactions between environmental variables in anthropogenically disturbed environments and physiological traits of invasive species may help explain reasons for invasive species' establishment in new areas. Here we analyze how soil contamination along roadsides may influence the establishment of Conium maculatum (poison hemlock) in Cook County, IL, USA. We combine analyses ...
Davis, Mark - - 2012
Garlic mustard, Alliaria petiolata (M. Bieb.) Cavara & Grande, is an introduced biennial forb that has commonly been referred to as highly invasive andas having substantial negative effects on other plants in the eastern deciduous forests of North America. However, several recent studies have documented only modest effects on other ...
Tavernia, Brian - - 2012
The exotic invasive wetland plant purple loosestrife (Lythrum salicaria) is often considered to have negative impacts on native plant and animal species, but this is debated. Clarifying its influence would provide insight into appropriate management actions following invasion. We investigated the influence of L. salicaria cover and density on abundances ...
Smith, Geoffrey - - 2012
Alterations of aquatic ecosystems, such as nutrient enrichment and changes in community composition, can potentially have effects that pervade the entire community. We investigated the effects of nutrient enrichment and changes in the presence and density of two species of tadpoles, American toad (Anaxyrus americanus) and Gray treefrog (Hyla versicolor), ...
Johnson, J. - - 2012
Understanding human impacts on biodiversity is a pressing challenge given the degree to which humans alter ecosystems. Urbanization is a prevalent example of human disturbance that often reduces species richness at the expense of dramatic population growth for certain urban-adapted taxa. The Western black widow spider, Latrodectus hesperus, is a ...
Riem, Jennifer - - 2012
Human development is changing the landscape in many ways that affect the distribution of wild species of mammals. Most previous work has focused on birds with only a few studies that examine the effects of urbanization on mammalian species. Using a combination of live trapping, track plates, and observation, we ...
Barrett, Dominic - - 2012
Examination of age structures and sex ratios is useful in the management of northern river otters (Lontra canadensis) and other furbearers. Reintroductions and subsequent recolonizations of river otters have been well documented, but changes in demographics between expanding and established populations have not been observed. As a result of reintroduction ...
Hoffman, Justin - - 2012
The adult sex ratio (ASR) is an important component of a population's demographics and can be used as an indicator of a population's status. However, the causes of annual variation in ASRs are unknown for many species. Fluctuations in ASR can arise through demographic stochasticity and intense selective harvesting. In ...
Hinton, Joseph - - 2012
Movement ecology of coyotes (Canis latrans) in the southeastern United States is poorly understood, despite the increasing recognition that coyotes are important predators throughout the region. During 2009-2011, we documented long-distance movements of three transient coyotes in northeastern North Carolina using Global Positioning System (GPS) collars. From their capture locations, ...
Ruell, E.W. - - 2012
Although habitat fragmentation is recognized as a primary threat to biodiversity, the effects of urban development on genetic population structure vary among species and landscapes and are not yet well understood. Here we use non-invasive genetic sampling to compare the effects of fragmentation by major roads and urban development on ...
Elizalde-Arellano, Cynthia - - 2012
Home range size, daily travel distances, and diel activity patterns are important characteristics of how an animal uses its home range area. In species, such as the bobcat (Lynx rufus), with large geographical ranges, it is necessary to gather data on diverse populations across the range to better understand what ...
Rulison, E.L. - - 2012
We compared relative impacts of habitat type vs. location in the diet of a generalist omnivore, the raccoon (Procyon lotor). Raccoon diets were analyzed from 161 scat samples collected in a marine coastal habitat over 13 mo. We used a suite of statistical tools including univariate indices of diversity, descriptive ...
Schade, Jennifer - - 2012
In teleost fishes, 11-ketotestosterone (11KT) is a critical androgen regulating primary and secondary sex characteristics. In the sexually dimorphic Lythrurus fasciolaris (Cyprinidae), dominant nuptial males display heavy tuberculation on the head and nape, dark dorsolateral vertical bars, and dramatic red coloration in the fins, venter, and operculum area. This study ...
Pendleton, Richard - - 2012
Many North American minnows (Cyprinidae) exhibit nest association, a spawning mode in which one species (associate) uses nests constructed by another species (host). Although this relationship may be obligate for some species, many nest associates can use alternative reproductive modes, indicating that the strength of the relationship between associate and ...
Mundahl, Neal - - 2012
Slimy sculpin Cottus cognatus are being reintroduced into coldwater streams in southeastern Minnesota to restore native biotic diversity and provide forage for large trout, but success has been variable. We examined slimy sculpin diets and prey consumption in a series of field and laboratory experiments to assess the potential role ...
Mundahl, Neal - - 2012
Slimy sculpin Cottus cognatus are being reintroduced into coldwater streams in the upper Midwestern United States, where they were extirpated by stream degradation during the early- to mid-1900s. Habitat use and selection by slimy sculpin were examined in nine coldwater tributaries of the Upper Mississippi River in southeastern Minnesota to ...
Gorney, Rebecca - - 2012
We characterized coldwater stream fish community response to habitat degradation and channelization for agriculture. Coldwater streams are not common in the lower midwestern United States, and these streams differ from warmwater streams with respect to their diversity and community response to degradation. Six sites were sampled on the coldwater Mac-o-chee ...
Webster, J.R. - - 2012
The death of eastern hemlock (Tsuga canadensis) trees in response to infestation by the introduced hemlock woolly adelgid (Adelges tsugae) may affect ecosystem processes and structure of streams. Prior to hemlock mortality, we documented the conditions of eight small streams and their associated riparian forests within the Appalachian Mountains of ...
Stucky, J.M. - - 2012
Pollination biology and factors affecting reproductive success of the federally endangered Echinacea laevigata (coneflower) were studied in one large and five small populations. Insect visitor exclusion from flowering heads and pollination treatments showed that seed production was 10x higher in open-pollinated treatments compared to bagged flowers that were not pollinated ...
Knopp, Peter - - 2012
Northern red oak (Quercus rubra L.) has been described as an opportunistic, pioneer species adapted to mesic sites, though its presence and site-specific occurrence in extreme soil-water conditions is not well understood. Fifty woodlots were investigated for the presence of Q. rubra on the Maumee lake plain of southeastern Michigan. ...
Howard, Jerome - - 2012
Human alterations of the environment may interact with natural disturbances to alter the characteristics of biological communities in unexpected ways. I studied vegetation plots in a leveed bottomland hardwood forest at Bayou Sauvage National Wildlife Refuge near New Orleans, LA to determine how Hurricane. Katrina affected the woody plant community ...
McEwan, Ryan - - 2012
Invasive species usurp habitat space at the expense of natives, reducing biodiversity and altering ecosystem function. The non-native invasive shrub Amur honeysuckle (Lonicera maackii) is known to have substantial effects on forest structure and biodiversity in Midwestern North America; however, its influence on nutrient cycling is relatively unexplored. We investigated ...
Hickerson, Cari-Ann - - 2012
Intraguild predation in structurally complex habitats is thought to weaken trophic cascades and increase food web stability. However, many predators commonly found in leaf litter become restricted to simple microhabitat beneath rocks and logs during periods between rains. It is within this structurally simple microhabitat that some predators defend rich ...
Kappler, Rachel - - 2012
Wild blue lupine (Lupinus perennis) in the Oak Openings Region of Northwest Ohio is an important nitrogen fixer and serves as an essential food source for the federally endangered Karner Blue butterfly (Lycaeides melissa samuelis). In order to examine potential factors that might be affecting mice predation on wild blue ...
Kwit, Charles - - 2012
The advantages of ant-mediated seed dispersal for myrmecochorous plants have often been framed in the context of directed dispersal and predator avoidance. Underlying and intertwining themes in these frameworks are the services of (a) moving seeds away from parent plants, (b) placing seeds in safe and ideal locations and occasionally, ...
Rose, Robert - - 2012
In this report of substantial syntopic populations, southern bog lemmings (Synaptomys cooperi) and woodland voles [Microtus (Pitymys) pinetorum] were the co-dominant rodents in a grassy oldfield in the absence of the large-bodied species of rodents common to the region. Southern bog lemmings achieved densities of 14 [ha.sup.-1] on one grid ...
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 ...
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