Digital Commons Network^™

Importance Of Succession, Harvest, And Climate Change In Determining Future Composition In U.S. Central Hardwood Forests, Wen J. Wang, Hong S. He, Frank R. Thompson Iii, Jacob S. Fraser, Brice B. Hanberry, William D. Dijak

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate successional stages where partial tree harvest is the primary disturbance. Changes in regional forest composition in response to climate change are often predicted for plant functional types using biophysical process models. These models usually simplify the simulation of succession and harvest and may not consider important species-specific demographic processes driving forests changes. We determined the relative importance of succession, harvest, and climate change to forest composition changes in a 125-million ha area of the Central Hardwood Forest Region of U.S. We used a forest landscape modeling …

Repeat Baseline Assessment In College-Age Athletes, Arthur C. Maerlender, Dennis L. Molfese

Department of Psychology: Faculty Publications

Repeat baseline testing scores from one collegiate Division I NCAA school were analyzed to determine the necessity of this practice. ImPACT tests were taken between 13 and 40 months apart (median 24 months; final N = 67). No significant difference in any test composite score was obtained; the number of tests exceeding chance levels of change was insignificant. The results do not support the recommendation for repeating baseline testing in college athletes; replication is recommended.

From Sex Objects To Human Beings: Masking Sexual Body Parts And Humanization As Moderators To Women’S Objectification, Philippe Bernard, Sarah Gervais, Jill Allen, Alice Delmée, Olivier Klein

Department of Psychology: Faculty Publications

Recent studies have shown that sexualized female bodies are objectified at a cognitive level. Research using the body-inversion recognition task, a robust indicator of configural (vs. analytic processing) within cognitive psychology, shows that for sexualized female bodies, people recognize upright and inverted bodies similarly rather than recognizing upright bodies better than inverted bodies (i.e., an inversion effect). This finding suggests that sexualized female bodies, like objects, are recognized analytically (rather than configurally). Nonetheless, it remains unclear when and why sexualized female bodies are objectified at a basic cognitive level. Grounded in objectification theory, the present experiments examine moderating factors that …

Impact Of Urban Nature On Executive Functioning In Early And Middle Childhood, Anne R. Schutte, Julia C. Torquati, Heidi L. Beattie

Department of Psychology: Faculty Publications

According to attention restoration theory, directed attention can become fatigued and then be restored by spending time in a restorative environment. This study examined the restorative effects of nature on children’s executive functioning. Sevento 8-year-olds (school aged, n = 34) and 4- to 5-year-olds (preschool, n = 33) participated in two sessions in which they completed an activity to fatigue attention, then walked along urban streets (urban walk) in one session and in a park-like area (nature walk) in another session, and finally completed assessments of working memory, inhibitory control, and attention. Children responded faster on the attention task after …

Role Of The Α1 Blocker Doxazosin In Alcoholism: A Proof-Of-Concept Randomized Controlled Trial, George A. Kenna, Carolina L. Haass-Koffler, William H. Zywiak, Steven M. Edwards, Michael B. Brickley, Robert M. Swift, Lorenzo Leggio

Department of Psychology: Faculty Publications

Evidence suggests that the norepinephrine system represents an important treatment target for alcohol dependence (AD) and the α1-blocker prazosin may reduce alcohol drinking in rodents and alcoholic patients. The α1-blocker doxazosin demonstrates a more favorable pharmacokinetic profile than prazosin, but has never been studied for AD. A double-blind placebo-controlled randomized clinical trial was conducted in AD individuals seeking outpatient treatment. Doxazosin or matched placebo was titrated to 16 mg/day (or maximum tolerable dose). Drinks per week (DPW) and heavy drinking days (HDD) per week were the primary outcomes. Family history density of alcoholism (FHDA), severity of AD and gender were …

Health-Related Strains And Subsequent Delinquency And Marijuana Use, Lisa Kort-Butler

Department of Sociology: Faculty Publications

General strain theory provides one framework for explaining the relationship between physical health and delinquency, pointing to mechanisms such as negative emotions, social bonds, and stress proliferation. Data from the National Longitudinal Study of Adolescent Health were used to examine these hypothetical mediators. Controlling for demographic factors, prior illicit behavior, and other strains, results from a series of regressions indicated that health-related strain (HRS) was positively associated with subsequent delinquency and marijuana use. Stressors at school were the primary mediators of these effects. Absences from school and social life due to health problems exerted an independent effect. The results lend …

Links Among Inflammation, Sexual Activity And Ovulation Evolutionary Trade-Offs And Clinical Implications, Tierney K. Lorenz, Carol M. Worthman, Virginia J. Vitzthum

Department of Psychology: Faculty Publications

Background and objectives: We examined a mechanism that may coordinate trade-offs between reproduction and immune response in healthy women, namely, changes in inflammation across the ovarian cycle.

Methodology: We investigated C-reactive protein (CRP), an inflammation marker, across two consecutive ovarian cycles in 61 Bolivian women. Participants provided saliva samples every other day, and dried blood spots on 5–6 days spread across weeks 2–3 of each cycle. Cycles were characterized as ovulatory/ anovulatory based on profiles of reproductive hormones. Participants also reported whether they were sexually partnered with a male or sexually abstinent during the study.

Results: High early-cycle, but not …

Longitudinal Predictors Of Homelessness: Findings From The National Longitudinal Survey Of Youth-97, Brittany Sznajder-Murray

Department of Sociology: Faculty Publications

Homeless youth represent a vulnerable and understudied population. Little research has prospectively identified factors that may place youth at risk for experiencing homelessness. The current study utilizes data from the National Longitudinal Survey of Youth-97 (NLSY-97) to examine predictors of experiencing homelessness as a young adult (before age 25). The NLSY-97 includes a nationally representative sample of 8,984 youth. Data were first collected from these youth when they were between the ages of 12 to 18 years. The current study examined whether individual and family risk factors reported during adolescence predict homelessness by the age of 25. The findings showed …

Characteristics Of Mothers Caring For Children During Episodes Of Homelessness, Melissa L. Welch-Lazoritz, Les B. Whitbeck, Brian E. Armenta

Department of Sociology: Faculty Publications

This study provides a description of the physical, psychological, and substance use problems of adult homeless women who are and are not caring for children. We also examined differences in the characteristics of these two groups of women. Interviews were conducted with 148 homeless women from three mid-sized U.S. cities, 24.3% of whom were caring for at least one child. Our results showed that women caring for children were more likely to be sheltered and have health insurance. Homeless women caring for children and solitary homeless women were generally similar in terms of substance abuse problems. However, rates of Borderline …

Estimating Vertex Measures In Social Networks By Sampling Completions Of Rds Trees, Bilal Khan, Kirk Dombrowski, Ric Curtis, Travis Wendel

Department of Sociology: Faculty Publications

This paper presents a new method for obtaining network properties from incomplete data sets. Problems associated with missing data represent well-known stumbling blocks in Social Network Analysis. The method of “estimating connectivity from spanning tree completions” (ECSTC) is specifically designed to address situations where only spanning tree(s) of a network are known, such as those obtained through respondent driven sampling (RDS). Using repeated random completions derived from degree information, this method forgoes the usual step of trying to obtain final edge or vertex rosters, and instead aims to estimate network-centric properties of vertices probabilistically from the spanning trees themselves. In …

Museum Monsters And Victorious Viruses: Improving Public Understanding Of Emerging Biomedical Research, Judy Diamond, Benjamin Jee, Camilla Matuk, Julia Mcquillan, Amy N. Spiegel, David Uttal

Department of Sociology: Faculty Publications

Although microbes directly impact everyone's health, most people have limited knowledge about them. In this article, we describe a museum and media public education campaign aimed at helping diverse audiences better understand emerging knowledge about microbes and infectious disease. Funded primarily by the Science Education Partnership (SEPA) program of the National Institutes of Health, this campaign involved crosscutting programs designed to extend impacts throughout a broad public audience.

Community-Level Barriers To Recovery For Substance-Dependent Rural Residents, Lance Brendan Young, Kathleen M. Grant, Kimberly A. Tyler

Department of Sociology: Faculty Publications

This article identifies potential barriers to substance use recovery associated with rural residence. The evidence is discussed and illustrated with examples. Fourteen specific barriers to substance abuse recovery are identified within 4 broad categories: access to treatment services, access to other professionals, access to peer support groups, and barriers to confidentiality. Although telehealth, expansion of mental health care, intensive referral, and other efforts might enhance access to care, the evidence suggests practitioners and researchers should remain aware of community-level barriers to recovery from substance use disorder and work with clients to overcome them.

Homeless Young People’S Experiences Of Caregiver Rejection, Rachel M. Schmitz, Kimberly A. Tyler

Department of Sociology: Faculty Publications

This paper explores the dynamics of caregiver rejection experienced by 40 homeless young adults 19–21 years of age. Using qualitative interviews, our findings reveal that nearly all of the youth reported at least one type of familial rejection that was intertwined with wider household conflict, and several youth experienced multiple types of rejection. Many young people reported “feeling like an outsider,” as they felt marginalized by family members and perceived a sense of outsiderness within their family networks. Some youth cited rejection when they were “betrayed by a primary caregiver for a significant other.” These intimate partners, such as a …

Patterns Of Substance Use Initiation Among Indigenous Adolescents, Les B. Whitbeck, Brian E. Armenta

Department of Sociology: Faculty Publications

Background—The data for this study come from an eight-wave panel study of Indigenous (Canadian First Nations and American Indian) adolescents from three U.S. reservations and four Canadian reserves.

Objectives—Our objective was to investigate variations in patterns of substance use initiation from early adolescence through early adulthood using data collected annually for 8 years.

Method—At baseline the sample included 675 Indigenous adolescents (M age = 11.10, SD = .83; 50.3% girls). First, we calculated cumulative rates of substance use initiation by age. We then examined whether the cumulative initiation rates were moderated by gender using logistic regression …

‘‘We Can Wipe An Entire Culture’’: Fears And Promises Of Dna Biobanking Among Native Americans, Roberto Abadie, Kathleen Heaney

Department of Sociology: Faculty Publications

This paper explores Native American perceptions on DNA biobanking. A qualitative study was conducted among self-declared Native Americans living off reservation in two Midwest cities. Findings demonstrate a paradox: Informants maintain strong hopes for the transformative power of gene-based research while voicing very particular social anxieties. Emerging genomic technologies elicit concerns over the potential for genetic stigmatization or discrimination based on race, preventing access to health insurance or employment. Frequently, social anxieties adopt the narrative form of conspiracy theories which portray powerful agents exploiting or abusing a disenfranchised population. We argue that while Native Americans do not have a monopoly …

Widespread Detection Of Antibodies To Leptospira In Feral Swine In The United States, K. K. Pedersen, K. L. Pabilonia, T. D. Anderson, S. N. Bevins, C. R. Hicks, J. M. Kloft, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

As feral swine continue to expand their geographical range and distribution across the United States, their involvement in crop damage, livestock predation, and pathogen transmission is likely to increase. Despite the relatively recent discovery of feral swine involvement in the aetiology of a variety of pathogens, their propensity to transmit and carry a wide variety of pathogens is disconcerting. We examined sera from 2055 feral swine for antibody presence to six serovars of Leptospira that can also infect humans, livestock or domestic animals. About 13% of all samples tested positive for at least one serovar, suggesting that Leptospira infection is …

Evaluating And Validating Abundance Monitoring Methods In The Absence Of Populations Of Known Size: Review And Application To A Passive Tracking Index, Lee R. Allen, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Rarely is it possible to obtain absolute numbers in free-ranging populations and although various direct and indirect methods are used to estimate abundance, few are validated against populations of known size. In this paper, we apply grounding, calibration and verification methods, used to validate mathematical models, to methods of estimating relative abundance. To illustrate how this might be done, we consider and evaluate the widely applied passive tracking index (PTI) methodology. Using published data, we examine the rationality of PTI methodology, how conceptually animal activity and abundance are related and how alternative methods are subject to similar biases or produce …

Is Anthropogenic Cougar Mortality Compensated By Changes In Natural Mortality In Utah? Insight From Long-Term Studies, Michael L. Wolfe, David N. Koons, David C. Stoner, Patricia Terletzky, Eric M. Gese, David M. Choate, Lise M. Aubry

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding the interplay between exploitation and natural mortality is essential to guiding sustainable conservation of wildlife. Exploitation of carnivores by humans has long been thought to result in compensatory reductions of natural mortality among survivors. If rates of human exploitation exceed natural mortality, however, such actions will ‘add’ to overall mortality and could imperil the sustainability of such actions. We applied competing risk analyses to >/= 16 years of data for heavily harvested and semi-protected cougar populations in Utah to test the additive and compensatory mortality hypotheses, while accounting for parameter uncertainty. We additionally tested for presence of the two …

An Individual-Based Model For Feral Hogs In Great Smoky Mountains National Park, Rene A. Salinas, William H. Stiver, Joseph L. Corn, Suzanne Lenhart, Charles Collins, Marguerite Madden, Kurt C. Vercauteren, Brandon S. Schmit, Ellen Kasari, Agricola Odoi, Graham Hickling, Hamish Mccallum

United States Department of Agriculture Wildlife Services: Staff Publications

The expansion of feral hog (Sus scrofa) populations in the United States has resulted in increased efforts to develop and implement control strategies designed to minimize the impacts done by this invasive species. We describe an individual-based model for feral hogs in Great Smoky Mountains National Park (GSMNP). The objectives of the model are to provide an understanding of the population dynamics of this feral hog population and to determine the efficacy of the annual harvest as a population control method. Results suggest that the dynamics of the population are driven by fall hard mast production and the …

Predator-Induced Renesting And Reproductive Effort In Indigo Buntings: More Work For Less Pay?, Dana L. Morris, John Faaborg, Brian E. Washburn, Joshua J. Millspaugh

United States Department of Agriculture Wildlife Services: Staff Publications

Renesting after nest predation is ultimately an adaptive response to increase productivity in birds. However, renesting also increases reproductive effort to replace lost clutches. We investigated the consequences of this increased reproductive effort by determining whether renesting in female indigo buntings (Passerina cyanea) is associated with a decline in body condition (size-corrected mass) and haematocrit and an increase in stress hormones and whether renesting or maternal body condition is associated with a decline in productivity (clutch size, nestling body condition). Next, because a consequence of multiple renesting attempts is a prolonged breeding season and later timing, we predicted …

Review Of The 2012 Epizootic Hemorrhagic Disease Outbreak In Domestic Ruminants In The United States, G Stevens, B Mccluskey, A. King, E O'Hearn, G Mayr

United States Department of Agriculture Wildlife Services: Staff Publications

An unusually large number of cases of Epizootic hemorrhagic disease (EHD) were observed in United States cattle and white-tailed deer in the summer and fall of 2012. USDA APHIS Veterinary Services area offices were asked to report on foreign animal disease investigations and state diagnostic laboratory submissions which resulted in a diagnosis of EHD based on positive PCR results. EHD was reported in the following species: cattle (129 herds), captive white-tailed deer (65 herds), bison (8 herds), yak (6 herds), elk (1 herd), and sheep (1 flock). A majority of the cases in cattle and bison were found in Nebraska, …

Impacts Of Colonial Waterbirds On Vegetation And Potential Restoration Of Island Habitats, Christopher R. Ayers, Katie C. Hanson-Dorr, Sadie O'Dell, Charles D. Lovell, Michael L. Jones, Jason R. Suckow, Brian S. Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Colonial waterbirds have impacted forested island ecosystems throughout their breeding range, changing vegetation, and soil characteristics and bird communities. Our objectives were to (1) determine effects of three levels of colonial waterbird exclusion on overall vegetation diversity and growth, and survival of a candidate restoration species (black elderberry; Sambucus nigra canadensis); (2) investigate effects of different planting techniques on survival and growth of black elderberry; and (3) determine effects of waterbird colonization on soil chemistry. In 2012, we investigated effects of three levels of waterbird exclusion (none control plots [CON]; partial, which excluded waterbirds larger than gulls [PEX]; and …

Carnivore Incidents With U.S. Civil Aircraft, Alexander R. Crain, Jerrold L. Belant, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife incidents with aircraft are of concern in the United States as they pose a risk to human safety and economic losses for the aviation industry. Most previous research on wildlife-aircraft incidents has emphasized birds, bats, and ungulates. We queried the Federal Aviation Administration’s National Wildlife Strike Database from 1990 to 2012 to characterize carnivore incidents with U.S. civil aircraft. We found 1016 carnivore incidents with aircraft representing at least 16 species, with coyotes (n = 404) being the species most frequently struck. California and Texas had the most reported incidents and incidents were most likely to occur at …

Influence Of Simulated Double-Crested Cormorant, Phalacrocorax Auritus, Predation On Multiple-Batch Production Of Channel Catfish,Ictalurus Punctatus, Brian S. Dorr, Carole R. Engle

United States Department of Agriculture Wildlife Services: Staff Publications

The double-crested cormorant, Phalacrocorax auritus, is considered the primary depredating bird species on commercially produced channel catfish, Ictalurus punctatus, in the southeastern USA. We simulated different levels of cormorant predation on losses at harvest and economic effects on channel catfish production in a multiple-batch cropping system. We observed significant (P<0.05) declines in catfish production at increasing levels of cormorant predation in this study. This decline was mitigated by increased individual growth of catfish at higher predation rates (i.e., lower catfish densities). This mitigating effect produced a non-linear relationship with total kg of catfish harvested per pond resulting in a non-linear incremental increase in breakeven price related to predation. Costs of production ($/kg) increased with increasing predation levels up to very high levels of predation with a cumulative maximum increase in breakeven price of $0.143/kg. These results indicate that losses at harvest due to cormorant predation occur immediately but are mitigated in part by compensatory growth of individual catfish. Losses due to cormorant predation in multi-batch systems can be considerable, but there is not a 1:1 relationship between losses and kg of catfish harvested due to compensatory factors.

Spatially Explicit Modeling Of Blackbird Abundance In The Prairie Pothole Region, Greg M. Forcey, Wayne E. Thogmartin, George M. Linz, Patrick C. Mckann, Shawn M. Crimmins

United States Department of Agriculture Wildlife Services: Staff Publications

Knowledge of factors influencing animal abundance is important to wildlife biologists developing management plans. This is especially true for economically important species such as blackbirds (Icteridae), which cause more than $100 million in crop damages annually in the United States. Using data from the North American Breeding Bird Survey, the National Land Cover Dataset, and the National Climatic Data Center, we modeled effects of regional environmental variables on relative abundance of 3 blackbird species (red-winged blackbird, Agelaius phoeniceus; yellow-headed blackbird, Xanthocephalus xanthocephalus; common grackle, Quiscalus quiscula) in the Prairie Pothole Region of the central United States. We …

Molecular Assessment Of Translocation And Management Of An Endangered Subspecies Of White-Tailed Deer (Odocoileus Virginianus), Matthew W. Hopken, Tod M. Lum, Paul M. Meyers, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Translocations are an effectual management strategy for the reestablishment and reconnection of endangered populations and species. However, knowledge about the evolution and ecology of the populations and species of interest are critical so that informed decisions can be made about source populations and reestablishment areas. We employed 614 base pairs of the mitochondrial control region and 15 microsatellite loci to investigate genetic variation, contemporary connectivity, and interspecific hybridization in the two remaining populations of the endangered Columbian white-tailed deer (Odocoileus virginianus leucurus) through comparisons with the closest subspecies, O. v. ochrourus. Our data revealed the dubious taxonomic …

Capillaria Hepatica Infection In Black Rats (Rattus Rattus) On Diego Garcia, British Indian Ocean Territory, Are R. Berentsen, Scott Vogt, Antenor N. Guzman, Daniel S. Vice, William C. Pitt, Aaron B. Shiels, Terry R. Spraker

United States Department of Agriculture Wildlife Services: Staff Publications

Rats (Rattus spp.) are among the most damaging invasive species worldwide. The accidental introduction of rats has caused significant detriment to native flora and fauna, crops, structures, and human livelihoods. Rats are vectors of disease and carriers of various zoonotic parasites. Capillaria hepatica (syn. Callodium hepaticum) is a parasitic nematode found primarily in rodents but is known to infect over 140 mammal species, including human beings and several species of domestic animals. In this case study, the presence of C. hepatica infection in black rats on Diego Garcia, British Indian Ocean Territory, is reported. Liver samples from …

Shifting Perceptions Of Risk And Reward: Dynamic Selection For Human Development By Black Bears In The Western United States, H. E. Johnson, S. W. Breck, S. Baruch-Mordo, D. L. Lewis, C. W. Lackey, K. R. Wilson, J. Broderick, J. S. Mao, J. P. Beckmann

United States Department of Agriculture Wildlife Services: Staff Publications

As landscapes across the globe experience increasing human development, it is critical to identify the behavioral responses of wildlife to this change given associated shifts in resource availability and risk from human activity. This is particularly important for large carnivores as their interactions with people are often a source of conflict, which can impede conservation efforts and require extensive management. To examine the adaptations of a large carnivore to benefits and risks associated with human development we investigated black bear behavior in three systems in the western United States. Our objectives were to (1) identify temporal patterns of selection for …

Chemical Repellents Appear Non-Useful For Eliciting Exit Of Brown Tree Snakes From Cargo, Fred Kraus, Randal S. Stahl, William Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

The brown tree snake (Boiga irregularis) is invasive in Guam, has imposed ecological and economic problems there, and threatens to be dispersed via cargo and vehicles to other islands in the Pacific, where it could be expected to inflict similar damages. Prevention of inadvertent snake export currently relies on cargo inspection and suppression of snake populations around ports, which are expensive and incompletely reliable. Hence, there has long been interest in developing additional tools to preclude snakes leaving in cargo, and fumigation with essential oils has been suggested for this role. We tested gaseous or aerosol deliveries of …

Limitations Of Population Suppression For Protecting Crops From Bird Depredation: A Review, George M. Linz, Enrique H. Bucher, Sonia B. Canavelli, Ethel Rodriguez, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Blackbirds (Icterinae) in North America, and dickcissels (Spiza americana Gmelin), eared doves (Zenaida auriculata Des Murs), and monk parakeets (Myiopsitta monachus Boddaert) in South America can cause serious economic damage to grain crops. Farmers frequently advocate lethal bird damage abatement measures based on the perceived need to take immediate action to avoid serious economic losses. In comparison, wildlife managers must make informed decisions based on a multitude of factors, including local, state, and national environmental laws, administrative restrictions, logistics, costs, expected outcome, and cultural considerations related to wildlife stewardship. In this paper, we focus on practicality, environmental …