The American Midland Naturalist

Articles from Vol. 168, No. 2, October

Black Widows in an Urban Desert: City-Living Compromises Spider Fecundity and Egg Investment despite Urban Prey Abundance
ABSTRACT.-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...
Comparing Predicted Historical Distributions of Tree Species Using Two Tree-Based Ensemble Classification Methods
ABSTRACT.-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...
Effects of Soil Disturbance on Success of a Rare Savanna Forb, Liatris Scariosa Var. Nieuwlandii in Habitats Dominated by Early and Late Successional Grasses
ABSTRACT.-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...
Effects of the Anuran Tadpole Assemblage and Nutrient Enrichment on Freshwater Snail Abundance (Physella Sp.)
Abstract.-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...
Establishment of an Invasive Plant Species (Conium Maculatum) in Contaminated Roadside Soil in Cook County, Illinois
ABSTRACT.-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...
Estimating Mammalian Species Diversity across an Urban Gradient
ABSTRACT. -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....
Examination of Annual Variation in the Adult Sex Ratio of Pronghorn (Antilocapra Americana)
ABSTRACT.-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...
Home Range Size and Activity Patterns of Bobcats (Lynx Rufus) in the Southern Part of Their Range in the Chihuahuan Desert, Mexico
ABSTRACT.-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...
Insect Ecology: Behavior, Populations and Communities
Review of Insect Ecology: Behavior, Populations and Communities, Peter W. Price, Robert F. Denno, Micky D. Eubanks, Deborah L. Finke and Ian Kaplan. Cambridge University Press, New York, New York, Hardback, $165.00, Paperback, $85.00, 801 p. ISBN 978-0-521-83488-9,...
Long-Distance Movements of Transient Coyotes in Eastern North Carolina
ABSTRACT.-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...
Recruitment and Dominance of Quercus Rubra and Quercus Alba in a Previous Oak-Chestnut Forest from the 1980s to 2008
ABSTRACT.-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...
Relative Impacts of Habitat and Geography on Raccoon Diets
ABSTRACT.-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...
Spatio-Temporal Variations in Age Structures of a Partially Re-Established Population of Northern River Otters (Lontra Canadensis)
ABSTRACT.-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...
Spawning of White Sucker (Catostomus Commersoni) in a Stormwater Pond Inlet
ABSTRACT.-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...
Structure, Species Composition, and Soil Characteristics in a Chronosequence of Jack Pine (Pinus Banksiana Lamb.) Stands on the Southern Shore of Lake Michigan
ABSTRACT.-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...
The Impact of Exotic Purple Loosestrife (Lythrum Salicaria) on Wetland Bird Abundances
ABSTRACT.-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...
The Population Dynamics and Ecological Effects of Garlic Mustard, Alliaria Petiolata, in a Minnesota Oak Woodland
ABSTRACT.-Garlic mustard, Alliaria petiolata (M. Bieb.) Cavara & Grande, is an introduced biennial forb that has commonly been referred to as highly invasive and as having substantial negative effects on other plants in the eastern deciduous forests...
Urban Habitat Fragmentation and Genetic Population Structure of Bobcats in Coastal Southern California
ABSTRACT.-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...
Use of Camera Traps to Examine the Mesopredator Release Hypothesis in a Fragmented Midwestern Landscape
ABSTRACT.-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...