Life Sciences Commons^™

Big Brains Stabilize Populations And Facilitate Colonization Of Variable Habitats In Birds, Trevor S. Fristoe, Andrew N. Iwaniuk, Carlos A. Botero

Biology Faculty Publications & Presentations

The cognitive buffer hypothesis posits that environmental variability can be a major driver of the evolution of cognition because an enhanced ability to produce flexible behavioural responses facilitates coping with the unexpected. Although comparative evidence supports different aspects of this hypothesis, a direct connection between cognition and the ability to survive a variable and unpredictable environment has yet to be demonstrated. Here, we use complementary demographic and evolutionary analyses to show that among birds, the mechanistic premise of this hypothesis is well supported but the implied direction of causality is not. Specifically, we show that although population dynamics are more …

Life-Shortening Wolbachia Infection Reduces Population Growth Of Aedes Aegypti, Eunho Suh, David R. Mercer, Stephen L. Dobson

Entomology Faculty Publications

Wolbachia bacteria are being introduced into natural populations of vector mosquitoes, with the goal of reducing the transmission of human diseases such as Zika and dengue fever. The successful establishment of Wolbachia infection is largely dependent on the effects of Wolbachia infection to host fitness, but the effects of Wolbachia infection on the individual life-history traits of immature mosquitoes can vary. Here, the effects of life-shortening Wolbachia (wMelPop) on population growth of infected individuals were evaluated by measuring larval survival, developmental time and adult size of Aedes aegypti in intra- (infected or uninfected only) and inter-group (mixed with …

Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis

Electronic Theses and Dissertations

Understanding population dynamics and how species interact with their environment are important components for conservation and management. Ruffed grouse (Bonasa umbellus) are a widely distributed and common game bird in North America and are a considered an important economic and cultural icon in Maine. Although they are a well-studied species, there has been little research focused on ruffed grouse population dynamics and habitat relationships in Maine. My thesis aims to improve this knowledge gap by focusing on research related to survival and harvest of ruffed grouse, as well as male ruffed grouse resource selection at breeding display sites. Ruffed grouse …

Integrating Black Bear Behavior, Spatial Ecology, And Population Dynamics In A Human-Dominated Landscape: Implications For Management, Jarod D. Raithel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American black bear (Ursus americanus) has made a robust recovery within the human-dominated, social-ecological systems characterizing the Mid-Atlantic United
States. For example, in northwestern New Jersey (NJ), USA, black bear abundance increased from an estimated 450-500 in 1996 to 3200-3400 in 2010. Bear recovery
coincided with increasing human populations, coupled with shifting settlement patterns toward sprawling suburban communities. Consequently, conflicts have rapidly proliferated over the past three decades and resulted in >1400 incidents of verified property damage, >400 livestock kills, >250 pet attacks and/or kills, seven human attacks and one human fatality since 2001. The New Jersey …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

Patterns In Greater Sage-Grouse Population Dynamics Correspond With Public Grazing Records At Broad Scales, Adrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. Casazza

Wildland Resources Faculty Publications

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004-2014, we modeled population trends in response to grazing level (represented by a relative grazing index) …

Effect Of Seed Morph And Light Level On Growth And Reproduction Of The Amphicarpic Plant Amphicarpaea Edgeworthii (Fabaceae), Keliang Zhang, Jerry M. Baskin, Carol C. Baskin, Xuejun Yang, Zhenying Huang

Biology Faculty Publications

Amphicarpic plants produce aerial and subterranean fruits on an individual plant, and these heteromorphic diaspores give rise to plants that differ in growth and ecology. Amphicarpaea edgeworthii is a summer annual amphicarpic species that grows over a range of light levels. We aimed to compare the response to shading intensity of plants of A. edgeworthii grown throughout their life cycle from aerial seeds (ASP) and from subterranean seeds (SSP). We hypothesized that vegetative and reproductive growth of plants from ASP and SSP respond differently to light. Plants were grown from ASP and SSP under 0, 46, 71 and 90% shading …

Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone

Virginia Journal of Science

Abstract

We used monthly live trapping for 2.5 years to evaluate the life-history features of the most common small mammal, Sigmodon hispidus (hispid cotton rat), in an old field at its northern limit of distribution on the Atlantic coast. Peak densities, achieved in late autumn or early winter, were among the highest recorded for the species and were more typical of marginal populations rather than of central ones. Unlike some other marginal populations, hispid cotton rats in eastern Virginia did not lose significant body mass over the winter (when few juveniles were present) and survival in winter was not significantly …