Life Sciences Commons^™

Natural Resource Decisions: Discount Rates, Time Horizons, And Evaluations, Amanda Hyman

Doctoral Dissertations

As effects from climate change accelerate, there is a pressing need for research that can improve people’s lives and safeguard the environment. Billions of dollars are invested annually in such projects. To invest that money wisely, we need to understand the effects of assumptions that underpin decisions but often go unstated, such as assumptions about discount rates and time horizons. We also need to understand how project design choices affect the management of natural resources, prioritization of conservation actions, and success of climate adaptation projects. My dissertation explores these topics. I ask if and how local natural resource users and …

Ecology And Conservation Of Grey Crowned Cranes (Balearica Regulorum) In Tanzania, Bridget Amulike

Doctoral Dissertations

Grey-crowned cranes (Balearica regulorum) are listed as endangered and their population throughout Africa has declined by 50% from the period of 1985–2004. The major causes for their population loss are mainly linked to habitat loss and the illegal capture of live birds and collection of their eggs and other parts. Currently, throughout Africa, little has been done to study and protect grey crowned cranes. In this study, I incorporated local people’s knowledge, using survey questionnaires to investigate the distribution of grey crowned cranes in Arusha, Kilimanjaro, Singida, and Mbeya Region in Tanzania. I also investigated the perception and attitudes …

Attitudes And Interactions Of Indigenous And Non-Indigenous People With Wildlife In The Northern Talamanca Mountains Of Costa Rica, Carolina Saenz-Bolaños

Doctoral Dissertations

In this study I investigated wildlife and human use of landscapes in the northern Talamanca Mountains of Costa Rica (Pacuare-Barbilla sector), including three contiguous protected areas (a national park, a forest reserve, and an indigenous territory), as well as surrounding unprotected areas. I describe and compare perceptions of wildlife by different social actors in the Pacuare-Barbilla sector, collecting information with a questionnaire as an instrument. I also inventoried and monitored the abundance and distribution of a variety of wildlife species occurring throughout the area using camera traps. The species with greater abundance or only occurrence in the national park were …

Costs Of Protected Areas In The United States, Diane Lebouille

Doctoral Dissertations

Protected areas, or land owned in fee by agencies and non-profits to further conservation goals, have traditionally been the go-to choice for conservation interests. The UN Environment World Conservation Monitoring Centre estimates that, currently, close to 15% of all terrestrial and inland water areas are protected. This figure falls short of the Aichi Biodiversity Target of 17% in 2020, that was added to the Convention on Biological Diversity by its 196 signatories in 2010. But as the Convention prepares to set new post-2020 targets, this percentage is expected to keep increasing. Although acquiring a parcel of land is only one …

Ecology And Conservation Of Immature Sea Turtles Across Multiple Scales, Lucas Griffin

Doctoral Dissertations

Considering many sea turtle populations are a fraction of their historic size and anthropogenic threats within the marine environment are increasing, additional data are imperative to help mitigate anthropogenic disturbances and to build resilience into sea turtle populations. In this dissertation, I present three data chapters focused on immature sea turtle ecology and conservation. These chapters evaluate sea turtle ecology and conservation at varying scales, ranging from mitigating human-wildlife interactions at the individual level, to coastal movements and space use at the ecosystem level, and to large scale climate change impacts at the population level. Ultimately, these chapters provide a …

Population Viability And Connectivity Of The Federally Threatened Eastern Indigo Snake In Central Peninsular Florida, Javan Bauder

Doctoral Dissertations

Understanding the factors influencing the likelihood of persistence of real-world populations requires both an accurate understanding of the traits and behaviors of individuals within those populations (e.g., movement, habitat selection, survival, fecundity, dispersal) but also an understanding of how those traits and behaviors are influenced by landscape features. The federally threatened eastern indigo snake (EIS, Drymarchon couperi) has declined throughout its range primarily due to anthropogenically-induced habitat loss and fragmentation making spatially-explicit assessments of population viability and connectivity essential for understanding its current status and directing future conservation efforts. The primary goal of my dissertation was to understand how …

Identifying Extinction Risk Patterns In Pollination Networks And Conservation Planning To Reduce The Cost Of Management-Necessitated Travel, Christine Elise Dumoulin

Doctoral Dissertations

Extinction rates are currently far above background levels, as a result of human activity. Although conservation spending is substantial, there is a shortfall between the cost of meeting biodiversity targets and the resources available to do so. Consequently, decision-makers are faced with the task of identifying which taxonomic groups and geographical regions are of greatest concern, and prioritizing approaches with the greatest conservation benefit. In this dissertation, I develop novel approaches in both of these areas.

First, I take a stochastic, community dynamic approach to modeling extinction risk patterns in pollination networks. Despite the ecological and agricultural importance of pollination …

Distribution And Population Dynamics Of Ungulates In The Mongolian Gobi, Buuveibaatar Bayarbaatar

Doctoral Dissertations

The Mongolian Gobi is one of the most spectacular and important regions in Central Asia, comprising the largest area of intact grassland in the world. In recent years, a growing human population, expanding exploitation of natural resources, and the development of infrastructure in the region place increasing pressure on these species and their habitats. This dissertation has focused on three species of ungulates such as Mongolian saiga (Saiga tatarica mongolica) in western Mongolia, and Asiatic wild ass (Equus hemionus), and goitered gazelle (Gazella subgutturosa) in Southern Gobi. The study on endangered saiga antelope in …

Regional Assessment Of The Relationships Of Conservation Practices To Northern Bobwhite And Other Priority Grassland Bird Breeding Populations, Christopher Manuel Lituma

Doctoral Dissertations

I documented populations of Northern Bobwhites (Colinus virginianus) and other priority grassland and early successional birds in the Central Hardwoods Bird Conservation Region (CHBCR), and determined whether conservation practices have been effective in positively impacting species occupancy and abundance. I designed and implemented a roadside survey by randomly locating five 15-km routes with 5-min unlimited distance point counts (30 counts/route), along secondary roads within Northern Bobwhite focal counties (n = 37) in the CHBCR. I also developed a survey to assess roadside biases for estimates of relative abundance (a), occupancy (ψ), detection probability (p), and associated …

Patterns Of Ecological Performance And Aquatic Insect Diversity In High Quality Protected Area Networks, Jason Lesley Robinson

Doctoral Dissertations

Protected areas are at the heart of plans for biodiversity conservation. Networks of protected areas may provide opportunities to protect conservation targets or objectives not attainable for single parcels of land. The landscape of potential decisions available to conservation planners is constrained by uncertainty about the form of future climate states. New methods are available that can provide objective assessments of the direction and magnitude of shifts in climate regimes that are not first filtered through theoretical responses of biodiversity. Successful predictions of where, in protected area networks, climates are most likely to change, or most likely to remain in …

Steps Toward Butternut (Juglans Cinerea L.) Restoration, Sunshine L. Brosi

Doctoral Dissertations

Butternut (Juglans cinerea L.), a lesser-known relative of black walnut (Juglans nigra L.), is a native tree species beneficial for wildlife, valuable for timber, and part of the great diversity of species in the eastern forests of North America. Populations of butternut are being devastated by butternut canker disease, caused by the fungus Sirococcus clavigignenti-juglandacearum (V.M.G. Nair, Kostichka, & Kuntz), which is thought to be introduced to North America. The disease causes multiple branch and stem cankers that eventually girdle trees. Small population sizes, lack of sprouting, and shade intolerance exacerbates the disease and results in permanent losses of butternut …