Matching Items (5)
Description
Since its inception in 1973, the Endangered Species Act has been met with both praise and criticism. More than 40 years later, the Act is still polarizing, with proponents applauding its power to protect species and critics arguing against its perceived ineffectiveness and potential mismanagement. Recovery plans, which were required by the 1988 amendments to the Act, play an important role in organizing efforts to protect and recover species under the Act. In 1999, in an effort to evaluate the process, the Society for Conservation Biology commissioned an independent review of endangered species recovery planning. From these findings, the SCB made key recommendations for how management agencies could improve the recovery planning process, after which the Fish and Wildlife Service and the National Marine Fisheries Service redrafted their recovery planning guidelines. One important recommendation called for recovery plans to make threats a primary focus, including organizing and prioritizing recovery tasks for threat abatement. Here, I seek to determine the extent to which SCB recommendations were incorporated into these new guidelines, and if, in turn, the recommendations regarding threats manifested in recovery plans written under the new guidelines. I found that the guidelines successfully incorporated most SCB recommendations, except those that addressed monitoring. As a result, recent recovery plans have improved in their treatment of threats, but still fail to adequately incorporate threat monitoring. This failure suggests that developing clear guidelines for monitoring should be an important priority in future ESA recovery planning.
ContributorsTroyer, Caitlin (Author) / Gerber, Leah (Thesis advisor) / Minteer, Ben (Committee member) / Guston, David (Committee member) / Arizona State University (Publisher)
Created2014
Description
A literature review summarizing the current status of conservation efforts of the Mojave Desert tortoise (Gopherus agassizii) including a brief overview of the Endangered Species Act (ESA) and its applicability to this species' conservation. A genetic and physiological comparison of the morphologically similar Mojave species with the Sonoran (Gopherus morafkai) species proceeded by an analysis of if and how the ESA should apply to the Sonoran population. Analysis of current plans and interagency cooperations followed by a multi-step proposal on how best to conserve the Sonoran population of Desert tortoise.
ContributorsKulik, Elise Chikako (Author) / Kusumi, Kenro (Thesis director) / Tollis, Marc (Committee member) / Wilson Sayres, Melissa (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Amsonia kearneyana is an endangered herbaceous plant endemic to a small area of the Baboquivari Mountains in southern Arizona. It exists in two distinct habitat types: 1) along the banks of a lower elevation ephemeral stream in a xeroriparian community, and 2) a higher elevation Madrean oak woodland on steep mountain slopes. Half of the largest known montane population (Upper Brown Canyon) was burned in a large fire in 2009 raising questions of the species capacity to recover after fire. This research sought to understand how the effects of fire will impact A. kearneyana's ability to recruit and survive in the burned versus unburned areas and in the montane versus xeroriparian habitat.
I compared population size, abiotic habitat characteristics, leaf traits, plant size, and reproductive output for plants in each habitat area for three years. Plants in the more shaded unburned montane area, the most populated population, presented with the most clonal establishment but produced the least amount of seeds per plant. The unshaded burned area produced more seeds per plant than in the unburned area. Lower Brown Canyon, the xeroriparian area, had the fewest plants, but produced the most seeds per plant while experiencing higher soil temperature, soil moisture, photosynthetically active radiation, and canopy cover than the montane plants. This could indicate conditions in Lower Brown Canyon are more favorable for seed production.
Despite ample seed production, recruitment is rare in wild plants. This study establishes germination requirements testing soil type, seed burial depth, temperature regimes, and shade treatments. Trials indicate that A. kearneyana can germinate and grow in varied light levels, and that soil type and seed burial depth are better predictors of growth than the degree of shade.
Finally, this study examined the law, regulation, policy, and physiological risks and benefits of a new management strategy and suggests that "conservation by dissemination" is appropriate for A. kearneyana. Conservation by dissemination is the idea that a protected plant species can be conserved by allowing and promoting the propagation and sale of plants in the commercial market with contingent collection of data on the fate of the sold individuals.
I compared population size, abiotic habitat characteristics, leaf traits, plant size, and reproductive output for plants in each habitat area for three years. Plants in the more shaded unburned montane area, the most populated population, presented with the most clonal establishment but produced the least amount of seeds per plant. The unshaded burned area produced more seeds per plant than in the unburned area. Lower Brown Canyon, the xeroriparian area, had the fewest plants, but produced the most seeds per plant while experiencing higher soil temperature, soil moisture, photosynthetically active radiation, and canopy cover than the montane plants. This could indicate conditions in Lower Brown Canyon are more favorable for seed production.
Despite ample seed production, recruitment is rare in wild plants. This study establishes germination requirements testing soil type, seed burial depth, temperature regimes, and shade treatments. Trials indicate that A. kearneyana can germinate and grow in varied light levels, and that soil type and seed burial depth are better predictors of growth than the degree of shade.
Finally, this study examined the law, regulation, policy, and physiological risks and benefits of a new management strategy and suggests that "conservation by dissemination" is appropriate for A. kearneyana. Conservation by dissemination is the idea that a protected plant species can be conserved by allowing and promoting the propagation and sale of plants in the commercial market with contingent collection of data on the fate of the sold individuals.
ContributorsYost, Tyna (Author) / Stromberg, Juliet (Thesis advisor) / McCue, Kimberlie (Committee member) / Bradshaw-Schulz, Karen (Committee member) / Arizona State University (Publisher)
Created2015
Description
This work is an assemblage of three applied projects that address the institutional and spatial constraints to managing threatened and endangered (T & E) terrestrial species. The first project looks at the role of the Endangered Species Act (ESA) in protecting wildlife and whether banning non–conservation activities on multi-use federal lands is socially optimal. A bioeconomic model is used to identify scenarios where ESA–imposed regulations emerge as optimal strategies and to facilitate discussion on feasible long–term strategies in light of the ongoing public land–use debate. Results suggest that banning harmful activities is a preferred strategy when valued species are in decline or exposed to poor habitat quality. However such a strategy cannot be sustained in perpetuity, a switch to land–use practices characteristic of habitat conservation plans is recommended. The spatial portion of this study is motivated by the need for a more systematic quantification and assessment of landscape structure ahead of species reintroduction; this portion is further broken up into two parts. The first explores how connectivity between habitat patches promotes coexistence among multiple interacting species. An agent–based model of a two–patch metapopulation is developed with local predator–prey dynamics and density–dependent dispersal. The simulation experiment suggests that connectivity levels at both extremes, representing very little risk and high risk of species mortality, do not augment the likelihood of coexistence while intermediate levels do. Furthermore, the probability of coexistence increases and spans a wide range of connectivity levels when individual dispersal is less probabilistic and more dependent on population feedback. Second, a novel approach to quantifying network structure is developed using the statistical method of moments. This measurement framework is then used to index habitat networks and assess their capacity to drive three main ecological processes: dispersal, survival, and coexistence. Results indicate that the moments approach outperforms single summary metrics and accounts for a majority of the variation in process outcomes. The hierarchical measurement scheme is helpful for indicating when additional structural information is needed to determine ecological function. However, the qualitative trend between network indicator and function is, at times, unintuitive and unstable in certain areas of the metric space.
ContributorsSalau, Kehinde Rilwan, 1985- (Author) / Janssen, Marco A (Thesis advisor) / Fenichel, Eli P (Thesis advisor) / Anderies, John M (Committee member) / Abbott, Joshua K (Committee member) / Arizona State University (Publisher)
Created2013
Description
The Committee on Rare and Endangered Wildlife Species (CREWS) of the U.S. Fish and Wildlife Service (FWS) made important and lasting contributions to one of the most significant pieces of environmental legislation in U.S. history: the Endangered Species Act of 1973 (ESA). CREWS was a prominent science-advisory body within the U.S. Department of the Interior (DOI) in the 1960s and 1970s, responsible for advising on the development of federal endangered-wildlife policy. The Committee took full advantage of its scientific and political authority by identifying a particular object of conservation--used in the development of the first U.S. list of endangered species--and establishing captive breeding as a primary conservation practice, both of which were written into the ESA and are employed in endangered-species listing and recovery to this day. Despite these important contributions to federal endangered-species practice and policy, CREWS has received little attention from historians of science or policy scholars. This dissertation is an empirical history of CREWS that draws on primary sources from the Smithsonian Institution (SI) Archives and a detailed analysis of the U.S. congressional record. The SI sources (including the records of the Bird and Mammal Laboratory, an FWS staffed research group stationed at the Smithsonian Institution) reveal the technical and political details of CREWS's advisory work. The congressional record provides evidence showing significant contributions of CREWS and its advisors and supervisors to the legislative process that resulted in the inclusion of key CREWS-inspired concepts and practices in the ESA. The foundational concepts and practices of the CREWS's research program drew from a number of areas currently of interest to several sub-disciplines that investigate the complex relationship between science and society. Among them are migratory bird conservation, systematics inspired by the Evolutionary Synthesis, species-focused ecology, captive breeding, reintroduction, and species transplantation. The following pages describe the role played by CREWS in drawing these various threads together and codifying them as endangered-species policy in the ESA.
ContributorsWinston, Johnny (Author) / Hamilton, Andrew (Thesis advisor) / Maienschein, Jane (Committee member) / Henson, Pamela (Committee member) / Collins, James (Committee member) / Minteer, Ben (Committee member) / Arizona State University (Publisher)
Created2011