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Tsai, Lin-wai. "The laws for protecting endangered species in Hong Kong and Singapore /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37117348.
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Wilkinson, Timothy John. "Cryopreservation of rare and endangered species." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312121.
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McGowan, Conor P. "Incidental take and endangered species demography." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5595.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2008.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on June 9, 2009) Vita. Includes bibliographical references.
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Robertson, Emma. "TRANSITIONS: Biophilia, Beauty and Endangered Plants." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/17875.
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While the science continues to underline the increasing risks posed by climate change, rallying the public to the cause has proved increasingly difficult. A major challenge is finding alternatives to the despair, hopelessness and consequent sense of disempowerment that confronting the realities of climate change can provoke. It is also the case that particular silent aspects of the impact of climate change – for example on the future viability of certain plant species – receive less public and political attention than others, such as catastrophic weather events. Artists have been active in exploring the impact of climate change through a variety of aesthetic strategies in attempts to address these challenges and mobilise complex understandings of the phenomenon. The response of this thesis is to focus on a specific issue and location – endangered Australian plants – and to experiment with a range of different artistic approaches, filtered through the lens of biophilia and beauty. The experimental artwork produced builds and demonstrates a bridge between botanical science, endangered plant species, and art, in relation to climate change. The PhD research makes four substantial contributions. First, it presents a different perspective on the applied use of art as a mode of enquiry into climate change, through creative agency and advocacy on the focused theme of endangered Australian plants. Second, the research explores and assesses alternative methods for making and reconceptualising static drawings into moving images, as a strategy to engage artistically and positively with the negative ecopsychology and ecoanxiety of climate change. Third, newly initiated, collaborative projects with non-arts partners are deployed to enhance audience engagement through the application of drawings. In parallel to this, conventional international and national exhibitions, publications and workshops are also realised as additional contributions to knowledge within different communities. Fourth, the research results in a document which explores a hopeful reconnection with nature through applying and embracing an aesthetic of beauty and meditative mindfulness. A Transmedia Art method is utilised to enhance broader community understanding of Eco Art, using a mindful, practice based research process.
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Ritchie, Shawn W. 1965. "Rescuing endangered knowledge : a systems approach." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9752.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 1999.Includes bibliographical references (leaves 80-81).
This research involves the identification and definition of"Endangered Knowledge" and outlines a tool that a firm can use to identify, capture, and reutilizes endangered knowledge. Endangered knowledge (EK) is valuable knowledge firms acquire during product development that has a high potential to be erased from a firm's memory. Two primary factors contribute to endangered knowledge. First, the firm does not believe the knowledge has future value, or does not take the time to correctly assess the value of the knowledge. Product development teams are usually under a great deal of time and financial pressures, and once a particular piece of knowledge has been acquired and applied to a specific process, it is quickly discarded. Second, an individual in a firm may realize that a piece of knowledge could have value to their team or another team in the future, but have no system in place which will enable them to effectively store and communicate that knowledge. In both cases, the knowledge is lost, ultimately costing the firm time and money to replace the lost learning. This paper can be broken up into four sections. The first section includes an introduction to endangered knowledge and provides two case studies where different product development teams wasted time and money because they were unable to access knowledge acquired by other members in their firm. The second section defines the terminology, (knowledge vs. information, learning vs. teaching, transfer vs. transform) and highlights knowledge management (KM) initiatives in existence today. The third section outlines five essential steps a knowledge management system must address in order to be effective. The final section introduces a new methodology product development teams can use to capture and reuse, or "rescue" endangered knowledge.
by Shawn W. Ritchie.
S.M.
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Herman, John. "Herpetofaunal communities in agroecosystems : the effect of farm management style /." See Full Text at OhioLINK ETD Center (Requires Adobe Acrobat Reader for viewing), 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1114016439.
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Littlefield, Joanne. "All Creatures Great and Small...and Endangered." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2007. http://hdl.handle.net/10150/622133.
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Costante, Delaney. "Endangered Species Act: Quantifying Threats Impacting Listing." W&M ScholarWorks, 2021. https://scholarworks.wm.edu/etd/1627047881.
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With species increasingly becoming imperiled due to anthropogenic activities, conservation practitioners are tasked with determining conservation priorities in order to make the best use of limited resources. The United States’ Endangered Species Act (ESA) has two listing statuses into which imperiled species are placed to receive protections: Threatened or Endangered. In the first chapter, our objective was to identify differences between Threatened and Endangered species beyond what is outlined in their ESA definitions. To our knowledge, this is the first study to compare listing status for species protected by the ESA on the basis of types and number of threats they face. For six broad-scale threats (habitat modification, overutilization, pollution, species-species interactions, environmental stochasticity, and demographic stochasticity), we investigated whether there is a difference in the number and types of threats which impact Threatened and Endangered species at the time of their listing. We found that Threatened (X̄ = 2.9, SD = 1.4) and Endangered (X̄ = 3.0, SD = 1.1) species were faced by a similar number of threats at their time of their listing. The only broad-scale threat that disproportionately impacted Endangered species more than Threatened species was demographic stochasticity; Endangered species were 1.9 times (95% CI = 1.4 -2.7) more likely to have this threat than Threatened species. We found four finer-scale demographic stochasticity threats (few individuals in one population, few individuals in multiple populations, lack of reproduction, and genetic loss) to be strong predictors of Endangered status. The similarities in the number and types of broad-scale threats faced by Threatened and Endangered species suggest that changes recently made to the ESA may be detrimental to the recovery efforts of future Threatened species. In the second chapter, our objective was to identify temporal trends in threats facing the four major phyla protected by the United States Endangered Species Act: angiosperms, arthropods, mollusks, and vertebrates. For 24 threat types, we created models to determine whether there was a linear, quadratic, or pseudo-threshold association between year and the probability that a phylum was listed with a given threat. We were able to identify temporal trends for 79% of the 96 possible threat-phylum combinations. We found that angiosperms had the highest peak probability of being listed with the greatest number of threats (N = 10), followed by mollusks (N = 8) and more distantly by arthropods (N = 4) and vertebrates (N = 2). We found that vertebrates had the greatest number of threats (N = 16) for which the year with their greatest probability of their being listed with a threat was their most recent year of listing. The other three phyla were similar to each other for this metric, mollusks having 12 and angiosperms and arthropods each having 11 threats peak in their most recent year of listing. We only identified one threat/phylum combination for which the maximum probability of their being listed with a threat was in their first year of listing (i.e., the threat has been consistently decreasing): authorized take impacting angiosperms. Overall, we believe our findings can be used to assist conservation efforts by identifying which threats have been decreasing or stable over time and which have been increasing that are in need of more attention.
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Peterson, Markus Nils. "Management strategies for endangered Florida Key deer." Texas A&M University, 2003. http://hdl.handle.net/1969/297.
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DA, ROS ZAIRA. "Recovery and restoration of marine endangered habitats." Doctoral thesis, Università Politecnica delle Marche, 2020. http://hdl.handle.net/11566/274535.
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La biodiversità marina regola il funzionamento ecosistemico, responsabile della produzione di beni e servizi importanti per la biosfera ed il benessere umano. I cambiamenti climatici globali e le attività umane stanno alterando la biodiversità degli oceani ed il funzionamento ecosistemico. Al momento, partendo dalla consapevolezza che le sole misure di conservazione non sono sufficienti a invertire la degradazione degli ecosistemi, è riconosciuto che il restauro ambientale è una azione di cruciale importanza per far fronte a questa minaccia. Tuttavia, è necessaria una maggiore conoscenza scientifica per rendere efficaci azioni di restauro, specialmente negli ambienti profondi che sono largamente sconosciuti. Tra le maggiori attività che avranno impatti sugli habitat marini vi sono lo sfruttamento di risorse minerarie e la pesca a strascico, le quali, risospendendo particelle polimetalliche e sedimenti, avranno effetti principalmente sulle specie bentoniche. In questa tesi, il Corallium rubrum, specie strutturante di elevata valenza ecologica, è stato esposto a questi due tipi di particolato. Dopo la rimozione della fonte di impatto, questo organismo è in grado di recuperare parzialmente tassi di alimentazione e la sua integrità tissutale. Questo esperimento fornisce utili informazioni non solo per meglio comprendere gli effetti di tali attività su organismi bentonici, ma anche per definire possibili misure di mitigazione attraverso una modulazione appropriata della loro intensità e durata.
Allevare in acquario specie di corallo minacciate potrà essere utile per futuri progetti di restauro che prevedono il trapianto di colonie donatrici. Una dieta appropriata da somministrare durante l’allevamento può avere effetti benefici sulla loro crescita ed il loro successo riproduttivo. In questa tesi, è stata studiata la selezione di cibo da parte di alcuni coralli profondi (Desmophyllum pertusum, Madrepora oculata and Dendrophyllia cornigera), i quali hanno mostrato una preferenza per il crostaceo Mysis relicta. I risultati ottenuti dalle analisi condotte sugli isotopi stabili hanno inoltre fornito nuove informazioni sulle nicchie trofiche occupate nel Mar Mediterraneo da queste specie.
Una volta ampliate le conoscenze sugli habitat e le specie da restaurare, è necessario valutare l’efficacia delle procedure di rispristino che si vogliono applicare. In questa tesi, sono stati studiati gli effetti di due esperimenti pilota di trapianto della fanerogama Cymodocea nodosa e della gorgonia Eunicella singularis su attributi di funzionamento ecosistemico. I risultati ottenuti indicano che il trapianto di tali organismi, se opportunamente pianificato, non solo garantisce la loro sopravvivenza, ma può anche avere effetti positivi su processi ecosistemici chiave.
Tuttavia, sono necessari ulteriori studi per valutare la possibile estensione di queste azioni per affrontare l'attuale scala spaziale di perdita di specie/habitat. Questo lavoro fornisce nuovi elementi per la comprensione dei potenziali benefici ecologici derivanti dal restauro ambientale e delle sue ricadute per la conservazione del capitale naturale.Marine biodiversity regulates ecosystem functions, which are responsible for the production of goods and services for the biosphere and human well-being. Global changes and human activities are altering ocean biodiversity and ecosystem functioning. At present, stemming from the awareness that conservation and management are often not enough to halt and revert the degradation of threatened ecosystems, it has been recognized that active restoration is crucial to cope with this issue. More knowledge is needed to make restoration actions effective, especially for the largely unknown deep ocean. Two of the main activities that will alter marine habitats are ore exploitation and bottom trawling that, resuspending polymetallic and sediment particles, will affect benthic species. In this thesis, the habitat-forming species Corallium rubrum was exposed to these types of particles. After the removal of the disturbance, its feeding rates and tissue integrity partially recovered. This experiment provides new insights on the consequences of these activities as well as on potential mitigation strategies by properly modulating their intensity and duration. Rearing endangered corals in aquaria can be useful for future projects that aim to restore degraded reefs by transplanting healthy colonies. An appropriate diet may positively impinge on their growth or reproduction success. In this perspective, I studied the food selection of cold-water corals (Desmophyllum pertusum, Madrepora oculata and Dendrophyllia cornigera) was studied and these species showed a preference for the crustacean Mysis relicta. Stable isotope analyses provided also novel information on the trophic niches occupied by these coral species in the Mediterranean Sea. After expanding the knowledge on the habitat or the species to be restored, it is necessary to evaluate the effectiveness of the restoration actions that it might be applied. In this thesis, the effects of two pilot transplantation experiments of the seagrass Cymodocea nodosa and the gorgonian Eunicella singularis on ecosystem functioning of surrounding sediments have been studied. The results showed that transplantation can be effective and that it can have also positive effects on key-ecological processes. However, further studies are needed to assess the potential of scaling-up these actions addressing the present scale of species/habitat loss. This work provides new elements for a better understanding of the potential ecological benefits that can contribute to the conservation of the natural capital.
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Snow, Melanie Jennifer. "Ovarian xenografting for the conservation of endangered species." Monash University, Dept. of Physiology, 2003. http://arrow.monash.edu.au/hdl/1959.1/9557.
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Ebbers, Tim. "Endangered Experiences in Nature : Designing for Future Nostalgia." Thesis, Konstfack, Experience Design, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-4739.
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When outdoor recreational activities are restricted, where can we find solitude, exploration and self-reliance? Endangered Experiences in Nature is a project that creates disruptive scenarios to question the relationship we have now with landscapes. A forecast in which stargazing is replaced by watching cyborg fireflies in the sky, food is genetically engineered and getting lost can only happen with the aid of special devices. The thesis uses the tools of experience design and future studies to explore the meanings and values of nature. I analyze the experiential perspective of access to nature and outdoor recreation by focusing on experiences that will likely become inaccessible in the near future. This thesis is not about preservation but stands aspiring for recreating values humans got until now from the close relationship with natural settings. In doing so, I aspire to generate new experiences. My work therefore focuses not on what nature is but what it means to perceive something as being natural, wild, unexplored, in an age where every part of nature has been explored and exploited. My original contribution focuses on using nostalgia as an active method to create new relationships with our environment. Certain things will need to be “artificial” in order to achieve “real” experiences. The project will focus on three scenarios placed in the near future (2040). Each case study extrapolates on a particular endangered experience in wilderness (solitude, exploration and self-reliance) and is set in 3 distinct landscapes located in The Netherlands, Sweden and Romania. By doing so, I touch upon different cultural and natural influences on my design process. All scenarios encompass artificial (engineered) surrogates that question the inaccessibility to experiences in natural landscapes. With the goal to create counter-experiences in the future and therefore formulate a new way to deal with our relationship with nature conceptually and physically.
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Qamaruz-Zaman, Faridah. "Conservation genetics of rare and endangered British orchids." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621726.
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Littlefield, Joanne. "Endangered or Not? Taxonomy of the Kanab ambersnail." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2007. http://hdl.handle.net/10150/622123.
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Rabung, Emily A. "U.S. Military Land Management and Endangered Species Conservation." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595240047775966.
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Wright, Belinda Ruth. "Genomic approaches to conserving the endangered Tasmanian devil." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16411.
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The Tasmanian devil is threatened with extinction in the wild due to the transmissible cancer, devil facial tumour disease (DFTD). This thesis aims to utilise conservation genomic techniques and apply them in novel ways to advance devil research and improve our understanding of both the disease and captive populations of devils. In the north west of Tasmania a few rare cases of devils have been recorded where DFTD has spontaneously regressed. The genomes of these regressed cases were sequenced along with control devils who succumbed to DFTD. I conducted a genome-wide association study to identify genomic variants that may underlie this rare ability for tumours to regress. Two key regions of the genome differed between cases and controls and may be involved in slowing of tumour growth, allowing time for an immune response to be mounted. The re-sequenced genomes also provided a resource for detection of variable regions for use in genotyping. Tasmanian devils suffer from low genetic diversity so identification of polymorphic markers is vital. I developed a custom genotyping assay for the Tasmanian devil targeting both neutral and functional regions of the genome. The assay has been used to assess genetic diversity in the captive devil insurance population. Relatedness and inbreeding appeared to be high amongst founders with just over 90% of allelic diversity that was brought in from the wild being passed on to the next generation. Diversity at a number of genes involved with behaviour was also investigated. Aggression and social interactions may be important factors in transmission of DFTD as tumours are spread by devils when they bite each other. Again diversity is found to be low and is presented as a baseline for future work investigating DFTD-mediated selection or genetic adaptation to captivity that may impact success of reintroduction to the wild. The research presented here makes a significant advancement in the field of conservation of the Tasmanian devil.
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Littlefield, Joanne. "Helping Endangered Species: The Desert Amphibian Breeding Project." College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/295847.
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Lyons, Reneé C. "Trips and Treks: Teaching Endangered Species Through Literature." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/2367.
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Tam, Yee-wa Audrey. "A study of fauna species endangered by traditional habits of Chinese communities in Hong Kong /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37117397.
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Harveson, Patricia Moody. "The impacts of urbanization on endangered florida key deer." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3085.
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Conservation of native wildlife is becoming increasingly difficult due to
continued human population growth and expansion. As the human population continues
to increase, so does the rate of consumption of our natural resources. As competition for
resources between man and wildlife continues, it is important to understand the effects
of urbanization on species. Endangered Key deer (Odocoileus virginianus clavium) are
endemic to the Florida Keys archipelago stretching southwest off the southern tip of
peninsular Florida. Key deer range is restricted to the Lower Florida Keys with
approximately 60% residing on Big Pine Key and 15% residing on No Name Key which
have undergone rapid human population growth and development over the past 30 years.
Urban development and its associated risk factors (i.e., habitat loss and fragmentation,
deer domestication, and deerÂvehicle collisions) have been cited as the greatest threat to
the Key deer population. For my dissertation research, I evaluated the impacts of 30
years of development on the Key deer population. My results suggest that increased
habitat fragmentation and increased road traffic have created areas of varying habitat
quality and mortality risk and have resulted in a source-sink system for Key deer on Big Pine Key. In my examination of Key deer metapopulation dynamics, I found a low
probability of deer colonizing 2 target outer islands (Sugarloaf and Cudjoe) through
dispersal alone in the next 20 years. Further, I examined the impacts of urbanization on
changes in Key deer population dynamics, behavior, and morphology. Collectively, my
results suggest that over the past 30 years Key deer have become more urbanized, which
in turn has influenced Key deer behavior and population viability. Behavioral
adaptations due to deer plasticity appear to have provided Key deer with mechanisms to
persist in a changing environment due to urbanization. However, the future ability of
Key deer to persist in a continuously urbanizing environment cannot be predicted. At
some threshold, urban development would become unsustainable, and, unlike other
forms of habitat change or environmental disturbances, urban development is in most
cases irreversible, requiring careful planning in habitat conservation strategies.
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Derbridge, Jonathan, and Jonathan Derbridge. "Ecology and Conservation of Endangered Territorial Species Under Invasion." Diss., The University of Arizona, 2018. http://hdl.handle.net/10150/626655.
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Biological invasions threaten biodiversity globally, and degraded ecosystems increase the potential for invaders to compete with threatened native populations. In natural systems, niche partitioning minimizes interspecific competition, but introduced species may alter expected outcomes by competing with ecologically similar species for scarce resources. Where food production is highly variable, coexistence of native and invasive competitors may depend on dietary niche flexibility. Territorial species under invasion face additional challenges to maintain economically defendable territories. From 2011-2016, we conducted removal and behavior experiments to determine effects of non-territorial introduced Abert’s squirrels (Sciurus aberti) on diet, space use, and territoriality of endangered Mount Graham red squirrels (MGRS; Tamiasciurus fremonti grahamensis) in their declining habitat in the Pinaleño Mountains, Arizona. We collected comparative data from Arizona sites of natural syntopy between Abert’s and Fremont’s squirrels (T. fremonti). Stable isotope analysis revealed similar dietary partitioning among populations. Experimental removals did not appear to affect MGRS diet. Space use by MGRS responded inconsistently to removals; territory sizes increased after the first removal, but did not change following the second removal. Territory sizes and body mass of MGRS were sensitive to conspecific population density and food production. Behavioral experiments showed MGRS were more aggressive than other Fremont’s squirrels (hereafter, red squirrels). Dietary flexibility of Abert’s squirrels may have facilitated coexistence with MGRS, possibly due to coevolved resource partitioning with red squirrels. However, aggressive territoriality toward Abert’s squirrels may incur fitness costs for MGRS especially during poor food production years. Climate change may reduce the advantage of ecological specialist species globally, and where introduced species are better-adapted to novel environmental conditions, native species may ultimately be replaced.
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Lander, Tonya Allen. "Landscape genetics of the endangered Chilean tree, Gomortega keule." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509973.
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Bercero, Otal María Rosa. "L'Aragonés, an endangered minority language : the case of Ayerbe." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5419/.
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Aragonese is a minority endangered language used in the Alto Aragon area. Ayerbe is a town found in the Plana de Uesca in Alto Aragon, and therefore it is considered to belong to a geographical area where the use of the Aragonese language finds itself in a significant state of decline compared to the use of Castilian Spanish. This study examines the extent to which this is true. The objective was to conduct a questionnaire amongst residents in Ayerbe in order to explore their language use, their perceptions of the language, their linguistic awareness and their affinity to the concept of Aragonese identity. The results suggest that the Aragonese language in Ayerbe is more widely read and understood than was previously thought. This investigation also considers the processes of normalisation and normativisation that will be necessary for the revitalisation of the language.
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Can, Özberk Bahattin. "Mapping the Flow of Theft Endangered Goods in EU." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20082.
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Every country in world has opportunities for different type of productions and this leads compensation. According to this, International Trade has become very important in all countries worldwide for ages; it helps the developing of the country and contributes more convenient area for the citizens. It is because nations have to live with trading. In this manner, many agreements are signed to get efficient merchandising because international trade contains many risks like intervention, political, non-acceptance, credit, war and also uncontrollable events. European Union can be considered as an agreement since its fundamental principal is free movement of people and goods.Increasing of movement of these goods around the European Union is seen as “easy pickings” by crime groups and nowadays society is facing with this criminal behavior. That motivation causes many problems for supply chain and logistics. Transportation systems are being tried to adjust as more secured while opportunity to thefts attacks to goods are rising.The complexity of this problem is tried to be solved by good reporting of incidents, pointing out the hot spots or the hot products which are related to EU. It is obvious that there is lack of good reporting or coordinating.According to this thesis a lot of work can be done in order to get brief look for the theft endangered goods which are on road and dangerous zones for theft attacks at EU. This thesis will map out specific countries, cities and positions that are particularly exposed to theft attacks. (For example, Schiphol Airport is chosen as the hottest spot and its hottest products are electronic and music devices while many reports and statistical works are being observed.)
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Stetten, George, Fred Koontz, Christine Sheppard, and Charles Koontz. "TELEMETRIC EGG FOR MONITORING NEST MICROCLIMATE OF ENDANGERED BIRDS." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613481.
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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, NevadaA series of artificial eggs has been developed for the New York Zoological Society to measure conditions in the nest of the white-naped crane (Grus Vipio). Investigations undertaken at the Bronx Zoo have endeavored to improve artificial incubation of the eggs of endangered species of birds. Artificial eggs were constructed and camouflaged so that a pair of birds would accept and incubate them. Inside each counterfeit egg, a radio telemetry transmitter was hidden to report on the temperature and humidity in the nest and the orientation of the egg itself with respect to gravity.
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Convery, Ken M. "Assessing Habitat Quality for the Endangered Red-cockaded Woodpcker." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/10136.
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This project had 2 major objectives. The first objective was to assess how well the revised U.S. Fish and Wildlife Service Foraging Habitat Guidelines depict good quality habitat for the red-cockaded woodpecker (Picoides borealis) at Camp Lejeune, NC. To accomplish this, I used multiple linear and logistic regression to examine the relationships between fitness, habitat use, home range size, and habitat characteristics described in the guidelines. I assumed that habitat characteristics that confer quality were related to higher fitness, greater habitat use, and reduced home range size. To a large extent, the guidelines are validated. Red-cockaded woodpeckers responded favorably to habitat that mimics the historical, mature, and fire-maintained pine forests of the southeastern U.S., characterized by high densities of large pines, low densities of small and medium pines, and a lush herbaceous groundcover. Variables positively associated with habitat use and fitness were associated with reduced home range size, and those negatively associated with habitat use and fitness with increased home range size. Percent herbaceous groundcover was a significant regressor indicative of quality in every model. The second objective was to assess how well USFWS foraging partitions represent habitat used by red-cockaded woodpeckers. I conducted home range follows of 23 groups of red-cockaded woodpeckers and estimated the percentage of each home range encompassed by partitions of varying radii. The percentage of the actual home range included in the partition increased as a function of partition radius. The standard 800 m circular partition, on average, included 91% of the home range, but significant variation existed between groups.Master of Science
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Convery, Ken. "Assessing Habitat Quality for the Endangered Red-cockaded Woodpcker." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/10136.
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This project had 2 major objectives. The first objective was to assess how well the revised U.S. Fish and Wildlife Service Foraging Habitat Guidelines depict good quality habitat for the red-cockaded woodpecker (Picoides borealis) at Camp Lejeune, NC. To accomplish this, I used multiple linear and logistic regression to examine the relationships between fitness, habitat use, home range size, and habitat characteristics described in the guidelines. I assumed that habitat characteristics that confer quality were related to higher fitness, greater habitat use, and reduced home range size. To a large extent, the guidelines are validated. Red-cockaded woodpeckers responded favorably to habitat that mimics the historical, mature, and fire-maintained pine forests of the southeastern U.S., characterized by high densities of large pines, low densities of small and medium pines, and a lush herbaceous groundcover. Variables positively associated with habitat use and fitness were associated with reduced home range size, and those negatively associated with habitat use and fitness with increased home range size. Percent herbaceous groundcover was a significant regressor indicative of quality in every model. The second objective was to assess how well USFWS foraging partitions represent habitat used by red-cockaded woodpeckers. I conducted home range follows of 23 groups of red-cockaded woodpeckers and estimated the percentage of each home range encompassed by partitions of varying radii. The percentage of the actual home range included in the partition increased as a function of partition radius. The standard 800 m circular partition, on average, included 91% of the home range, but significant variation existed between groups.Master of Science
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Convery, Ken M. "Assessing habitat quality for the endangered red-cockaded woodpecker." Connect to this title online, 2002. http://scholar.lib.vt.edu/theses/available/etd-11042002-101356/.
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Mounce, Hanna Lee. "Recovery of the endangered Maui Parrotbill (Kiwikiu, Pseudonestor xanthophrys)." Thesis, University of Kent, 2015. https://kar.kent.ac.uk/50697/.
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Species recovery programs are tasked with reversing the declines of threatened and endangered species and mitigating the threats to their populations. These goals must be accomplished in the face of a human dominated global landscape where habitat destruction and alteration is still increasing at an alarming rate. Hawaii, as common on many islands, has one of the highest historical extinction rates in the world. Here I use the Maui Parrotbill (Kiwikiu; Pseudonestor xanthophrys) to explore population demographics, genetics, population viability, and recovery options for one of Hawaii’s most critically endangered passerines (Maui Island endemic, pop. ~500). The accurate estimation of key demographic parameters is invaluable for making decisions about the management of endangered wildlife. Due to the challenges of data collection on a rare and cryptic species that inhabits remote terrain, such estimates are often difficult to obtain and reliable basic demographic data was not before available for parrotbills. First I look at parrotbill productivity estimates through both nest success and annual reproductive success measures. Secondly, I look at annual survival based on an 18 year encounter history. These studies both suggest population limitations may be coming from fecundity, and juvenile and female survival. Maui Parrotbill once inhabited a variety of forest types throughout Maui Nui but are now restricted to a single strip of wet forest 40-50 km2 in size. I quantified the levels of contemporary genetic diversity and structure in wild and captive Kiwikiu populations, and compared these genetic patterns to those observed within historical nuclear diversity derived from 100-year old museum samples enabling the design of a conservation translocation strategy that is tailored to the patterns of genetic structure across the species’ range. Lastly, I combine these data into a comprehensive population viability model to assess the risks to this population and evaluate the impacts of recovery options to the overall viability trajectory of a species. In planning for a reintroduction of parrotbills to areas of their former range, this model provides managers with demographic benchmarks that the new population will need to meet in order for the reintroduction to be successful.
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Gath, Helen Claire. "Conservation management of the endangered Mauritius parakeet, Psittacula echo." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10045494/.
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Effectively managing wild populations requires drawing upon a range of skills from multiple scientific disciplines. Given the current biodiversity crisis the world now faces, developing these skills is a high priority in conservation science. Improving the success of species recovery programmes and sustaining them requires adopting the correct monitoring regime and implementing suitable restorative tools. To then evaluate their effectiveness and adjust methods accordingly is fundamental to ensuring continued success. The principal aim of this study has been to explore key approaches to conservation practice and their suitability for the management of the Mauritius (echo) parakeet, once considered the rarest parrot in the world. Nearly 25 years after intensive recovery efforts were initiated, their conservation is entering a new phase that looks toward a long-term strategy of minimal management. Achieving this requires a basic knowledge of the population’s demography and an assessment of the demographic response to management actions and infectious disease, knowledge which to date, has remained limited Accurately estimating demographic rates is a cornerstone to assessing the impact of management strategies or environmental conditions. Capture-mark-recapture (CMR) data plays an important role in this, but the accuracy of multistate models used to interpret such data is well debated when a species’ life history includes unobservable states. My analysis explored such potential inaccuracies and found that for the echo parakeets at least, unobservable multistate models led to biased estimates of vital rates and excluded important information regarding transitions between states. Combining the extensive CMR data with detailed breeding records, I explored the demographic impact of supplementary feeding (SF), a widely employed conservation tool but one often reporting varied responses from target populations. This study quantified the positive impact that SF has had on fecundity rates, which no doubt played a key role in the population’s growth. However, further work as part of this study also revealed that SF exacerbated the negative impact of an outbreak of psittacine beak and feather disease. I explore the extent of the outbreak and its demographic impact during and after its emergence in the echo population, and discuss the value of my findings in the context of the growing global threat of emerging infectious disease. The findings from my research provide a basis of vital information that could support evidence-based adaptations to the current management programme. Understanding the influence of management strategies will lead management toward better targeting and more efficient use of resources that will ultimately help to ensure the long term survival of the echo parakeet.
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Xego, Sibusiso. "Hydroponic propagation of Siphonochilus aethiopicus: an endangered medicinal plant." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2421.
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Thesis (MTech (Horticultural Sciences))--Cape Peninsula University of Technology, 2017.The increasing demand for medicinal plants has led into serious over-harvesting of wild populations and presents an opportunity for potential profitable cultivation. Production of medicinal plants in controlled environments particularly hydroponic technology provides opportunities for high quality biomass accumulation and optimizes production of secondary metabolites. Water availability and supplies are becoming scarce, thus search for innovative irrigation practices is desirable and vital. The proper irrigation interval and growing media can play a major role in increasing the water use efficiency. Thus, Siphonochilus aethiopicus was cultivated by means of the hydroponic technique, under various substrate combinations and watering regimes.
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Zuccon, Giulia. "Integrating genetic analyses and morpho-cellular approaches to sustainably conserve the marble trout (Salmo marmoratus Cuvier, 1817) population." Doctoral thesis, Università degli studi di Ferrara, 2017. http://hdl.handle.net/11392/2487866.
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The 2013 IUCN Red List included the marble trout (Salmo marmoratus), already listed in Annex II of EU Habitat Directive (92/43/EEC), in the Critically Endangered (CR) category although in the last decades many project were dedicated to the conservation of the taxon. Since the beginning of the 20th century the brown trout (Salmo trutta) has been introduced in the habitat of marble trout. This overlapping of distribution range resulted into hybridization: the native marble trouts are nowadays rare in most rivers and this determines a low number of breeders in the wild and a low production of pure offsprings every year. Regarding this, nowadays is fundamental a genetic carachterization of the breeders to ensure a high level of selection of the individuals that has to be directed to the reproductive career. The aim of this work is to select genetic strains of marble trout in order to breed them in a selected structure finalised in fish species conservation. For this reason, integrating genetic analyses and an innovative approach based on morpho-cellular quali-quantitative evaluation can lead to the accomplishment of a live gene-bank, a hatchery whose aim is to breed higly selected offsprings for restocking purposes. 229 fish were submitted to a strict phenotypic selection based on some peculiar morphological traits, before the transfer in the hatchery, then were tagged with a PIT-TAG to identify them later. The D-loop region and nuclear gene LDH- C1* were amplified to exclude hybrid individuals before next analyses. On a subset of 90 individuals resulting marble/Mediterranean, for the mtDNA and nDNA analyses, and an outgroup of 24 Mediterranean trout (Salmo cettii) was run a panel of 15 microsatellites in order to investigate the genetic diversity. The analyses showed a clear difference between individuals from the three different basins therefore, for the artificial fertilization, the three populations were maintained separated. However, from the plot was also evident a genetic pollution in the trouts from two hatcheries and one individual showed even a high percentage of genetic similarity with Mediterranean trouts proving the efficacy of the analyses conducted. Sperm motility and milt concentration were measured in the hatchery during the reproductive season by dark-field microscope and SDM6 photometer. Milt from the individuals that showed higher values of genetic variability has been used for the artificial fertilization and cryopreserved for future breeding. Nine males were sampled periodically in order to monitor the possible milt concentration variation during the reproductive season. In addition an egg fertilization experiment was conducted to test some artificial fertilization product.
Combining molecular tools and innovative techniques can be an important innovation in hatcheries both for commercial and conservation purposes. Being able to select and cryopreserve gametes of marble trout breeders and that carry the higher genetic variability is really important in order to maintain endangered species.La Lista Rossa IUCN del 2013 ha classificato la trota marmorata (Salmo marmoratus), già presente nell’Allegato II della Direttiva Habitat (92/43/EEC), “a maggior rischio” (CR, Critically Endangered) nonostante numerosi progetti negli ultimi decenni siano stati dedicati alla salvaguradia del taxon. Fin dall’inizio del 20esimo secolo negli habitat della trota marmorata è stata introdotta la trota fario (Salmo trutta). Questa sovrapposizione nei range di distribuzione ha avuto come risultato l’ibridazione: le trote marmorate autoctone oggigiorno sono rare, nella maggior parte dei fiumi, determinando un numero basso di riproduttori in natura e una bassa produzione di prole pura ogni anno. A tal riguardo è oggi fondamentale una corretta caratterizzazione genetica dei riproduttori per assicurare un alto livello di selezione degli esemplari da avviare alla carriera riproduttiva. Lo scopo di questo lavoro è di selezionare ceppi genetici di trota marmorata per allevare gli animali in strutture selezionate finalizzate alla conservazione di specie ittiche. A tal proposito, l’integrazione di analisi genetiche e di un approccio innovativo basato su una valutazione quali-quantitativa morfo-cellulare può portare alla creazione di una live gene-bank, ossia di un allevamento il cui scopo è quello di produrre progenie altamente selezionata per scopi di ripopolamento. 229 pesci sono stati sottoposti ad una rigida selezione fenotipica, basata su alcuni tratti morfologici peculiari, prima del trasferimento in allevamento, quindi sono stati taggati con un PIT-TAG per poterli identificare in seguito. La regione della D-loop e il gene nucleare LDH- C1* sono stati amplificati per escludere gli ibridi prima delle analisi seguenti. Per indagare la diversità genetica è stato testato un pannello di 15 loci microsatelliti su un sottoinsieme di 90 individui risultati marmorata/Mediterranea, per le analisi sul mtDNA e sul nDNA, e su un outgroup di 24 trote mediterranee (Salmo cettii). Le analisi hanno mostrato una chiara differenza tra gli individui provenienti da tre diversi bacini fluviali e di conseguenza, per le riproduzioni artificiali, le tre popolazioni sono state mantenute separate. Tuttavia, dal grafico ottenuto è stato evidente anche un inquinamento genetico nelle trote provenienti da due allevamenti e un individuo ha mostrato un’alta percentuale di somiglianza genetica con l’outgroup di trote mediterranee, confermando l’efficacia delle analisi condotte. La motilità spermatica e la concentrazione del liquido seminale sono stati misurati nell’allevamento durante la stagione riproduttiva con un microscopio ottico e il fotometro SDM6. Il liquido seminale degli individui che hanno fatto registrare i valori più alti di variabilità genetica è stato utilizzato per le fecondazioni artificiali e crioconservato per futuri accoppiamenti. Nove maschi sono stati campionati periodicamente per monitorare la possibile variazione nella concentrazione spermatica durante la stagione riproduttiva. In aggiunta è stato condotto un esperimento con la fecondazione di uova per testare alcuni prodotti commerciali. Combinare strumenti molecolari e tecnologie innovative può costituire un’importante innovazione negli allevamenti sia a scopo commerciale che di conservazione. Essere capaci di selezionare e crioconservare i gameti di riproduttori con alta variabilità genetica di trota marmorata pura è veramente importante per preservare specie in pericolo.
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King, Narelle Gaye. "Tourism based on reintroductions of threatened mammals achieving positive conservation outcomes /." Diss., Click here to access, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070212.113043.
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Filipski, Jules. "Reproductive biology of the endangered plant, Phlox hirsuta (E.E. Nelson)." View full-text version online, 2005. http://soda.sou.edu/awdata/060221b1.pdf.
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Thesis (M.S.) --Southern Oregon University, 2005."A thesis submitted to the Department of Biology and the Graduate School of Southern Oregon University in partial fulfillment of the requirements for the degree of Master of Science in Science." Includes bibliographical references (p. 69-75) Also available via Internet as PDF file through Southern Oregon Digital Archives: http://soda.sou.edu. Search Bioregion Collection.
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Kreivi, M. (Marjut). "Conservation genetics and phylogeography of endangered boreoarctic seashore plant species." Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514290190.
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Abstract
The amount and distribution of genetic diversity are likely to affect the evolutionary potential of a species. When feasible and cost-effective policies for management and monitoring of endangered populations or species are planned, knowledge of the spatial genetic structure and the type of population dynamics is of great concern. In this thesis the genetic diversity and population structures of two endangered arctic plant species was examined on different geographical scales in Northern Europe. The species were Siberian primrose (Primula nutans) and pendant grass (Arctophila fulva), which both grow in a seashore habitat and have similar distribution patterns on the shores of the Arctic Ocean and the Bothnian Bay.
The goal of the present study was to provide basic population genetic information for the study species using microsatellite and AFLP markers. Both markers were used for the first time in these species, and species-specific microsatellite markers were developed during the study. A further aim was to interlink the population genetic processes of the species into distribution patterns at the regional and population levels and to compile a synthesis of the impact of hierarchical spatiotemporal processes and autocorrelation in genetic variation at different levels.
The studies of this thesis provided new information on the diversity and population structure of the endangered study species and new markers that are useful in future genetic studies of primrose species. The diversity of Siberian primrose was low, and there was no dispersal between the study regions. In pendant grass, a relatively high amount of variation was found considering the evident clonal reproduction and gene flow that was detected between populations connected by waterways. The results suggested that both clonal and sexual reproduction are important in this species. On a local scale, pendant grass populations had characteristics of “stepping stone” and classical metapopulation models.
The results indicated that on a long time scale, both species will continue to decline without efficient management efforts. Most critical for the persistence of the species is the conservation of suitable habitats. Translocations could be considered in order to enhance the diversity of existing populations and establish new populations.
By examining the present day structure of Siberian primrose, it was possible to make inferences regarding the colonisation history of the species in the North European area. The current distribution of Siberian primrose seemed to result from a vicariant process that took place after the last ice-age, when the species colonised the area. It spread first to the White Sea area, probably from the east, and subsequently colonised the Bothnian Bay and the Barents Sea in the west. The isostatic land uplift after the retreat of the Eurasian ice sheet uncovered large areas of land from the Baltic Sea basin that previously were under water. These geological changes resulted in the current disjunct distribution of Siberian primrose.
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Hens, H. (Hilde). "Population genetics and population ecology in management of endangered species." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526215853.
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Abstract Knowledge of the determinants of the viability of populations is essential in order to undertake effective conservation and management of endangered species. In this study, long-term demographic data was combined with genetic data to study the viability of an endangered orchid species, Epipactis atrorubens. The genetic analyses revealed low levels of genetic variation and the presence of population genetic differentiation independent of the spatial scale. Low levels of seed-mediated gene flow, possibly linked to low seedling recruitment, is the likely cause of the low levels of gene flow. Indications of slow post-glacial colonisation rates were found, which together with the low gene flow predict a limited capacity of the species to shift its range to more suitable habitats after environmental change. Low genetic variation as a proxy for low evolutionary potential also suggests that the species has limited capacity to adapt to new environmental conditions. Furthermore, poor seedling recruitment lowers population viability in small populations, as highlighted by the low population growth rates. In addition, we found a strong effect of stochasticity that limits the viability of populations. Both the genetic and demographic analyses indicated low viability of the studied species and that seedling recruitment could be the main determinant for the viabilityTiivistelmä Luonnonsuojelun perusta on populaatioiden elinkykyyn vaikuttavien tekijöiden tuntemus. Tässä väitöskirjatyössä tutkittiin uhanalaisen orkidean, tummaneidonvaipan (Epipactis atrorubens), elinkykyyn vaikuttavia tekijöitä yhdistämällä pitkäaikaisseurannoilla kerätyt demografiset aineistot geneettisin menetelmin kerättyihin aineistoihin. Lajin populaatioiden geneettisen muuntelun määrän havaittiin olevan pieni ja populaatioiden todettiin olevan geneettisesti erilaistuneita maantieteellisestä skaalasta riippumatta. Geneettisen erilaistumisen syy voi olla alhainen geenivirta, joka on seurausta vähäisestä siemendispersaalista ja huonosta taimettumisesta. Populaatioiden evolutiivista historiaa tutkittaessa havaittiin merkkejä hitaasta jääkauden jälkeisestä kolonisaatiosta, mikä yhdessä alhaisen geenivirran kanssa ennustaa, että lajilla on huono kyky siirtyä sille sopivammille alueille, jos ympäristö muuttuu. Huonoa evolutiivista potentiaalia kuvastava vähäinen geneettinen muuntelu ennustaa, että lajilla on huono kyky sopeutua uusiin ympäristöoloihin. Tämän lisäksi huono taimettuminen laskee elinkykyä etenkin pienissä populaatioissa, mikä näkyy muun muassa pienten populaatioiden matalina kasvukertoimina. Stokastinen vaihtelu vaikutti elinkykyä alentavasti, mikä pitäisikin huomioida nykyistä paremmin elinkykyanalyyseissä. Sekä geneettiset että demografiset analyysit osoittivat taimettumisen mahdollisesti olevan määräävä tekijä tummaneidonvaipan populaatioiden elinkyvylle
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Johnson, Connie Nicole. "Stem cutting propagation of the endangered species, Clematis socialis (Kral)." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Theses/JOHNSON_CONNIE_58.pdf.
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Willis, Susan Denise Margaret. "The classification and management of limestone pavements : an endangered habitat." Thesis, University of Chester, 2011. http://hdl.handle.net/10034/200750.
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This thesis describes an in-depth study of limestone pavements across North West England and North Wales. The aim was to combine elements of geodiversity and biodiversity in order to create a holistic limestone pavement classification to inform future management. A field-based research protocol was used to assess a stratified random sample (46 pavements), accounting for approximately 10% of the limestone pavements in the geographical area. Detailed analyses of key elements are presented, along with important issues that continue to pose threats to this Annex One Priority Habitat. This research resulted in a comprehensive classification, using TWINSPAN analysis and Nonmetric Multidimensional Scaling, identifying six distinct holistic functional groups. The prime factors driving limestone pavement morphology, and hence the classification, were established to be lithology, proximity to structural fault, altitude and human intervention, particularly in terms of grazing intensity. Three upland, open limestone pavement classes were formed. Of these, the richest in terms of geodiversity and biodiversity was the group with the thickest bedding planes and hence the deepest grikes, typically greater than 1m. The class that was most species-poor was "at the highest altitude (above 450m), formed on the thin limestones of the Yoredales. These were characterised by shallow, wide grikes. The third upland limestone pavement group had mid-range grikes, generally 0.5-1m in depth, and small clints. Two wooded classes were identified. One was a lowland 'classic' wooded limestone pavement group with deep, narrow grikes and shallow soils. Indicator species included Juniperus communis and Taxus baccata. The second wooded group was situated proximal to a major structural fault. In this group the pavement dip ranged between 10°-40° with well-runnelled clints that were heavily moss-covered. The sixth group was low altitude, proximal to the coast, characterised by low moss growth, un-vegetated clints and the presence of Ulex europaeus. Conservation management was identified as key to the quality of the limestone pavement habitat and this thesis identifies best management practises and links these to the holistic limestone pavement classification. Finally, as a sample case study, this thesis presents mollusc species and diversity from eleven of the Yorkshire limestone pavements. Analysis establishes significant links between geodiversity and mollusc populations, with key drivers for mollusc communities echoing those of plant species on limestone pavement.
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Bunbury, Nancy. "Parasitic disease in the endangered Mauritian pink pigeon Columba mayeri." Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429604.
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Tollington, Simon. "Ecological immunology and genetic diversity of the endangered Mauritius parakeet." Thesis, University of Kent, 2012. https://kar.kent.ac.uk/64301/.
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Studies of avian ecological immunology attempt to describe the biotic and abiotic factors which explain natural variation in immune function within and among free-living bird species. Understanding this variation and the trade-offs associated with maintaining appropriate immune defences and individual life history variables has important implications for the conservation of endangered species, many of which are characterised by small population size and reduced genetic diversity. Such species often display increased susceptibility to infectious diseases as a result of inbreeding depression and are prone to the effects of novel parasites and pathogens. This thesis aims to explain the variation in immune function in the endangered, island-endemic Mauritius parakeet (Psittacula echo), a species which has passed through a considerable population bottleneck but now thrives by virtue of ongoing conservation management despite the presence of a highly infectious disease. Identifying the ecological, environmental and genetic elements which define individual immunity offers the potential to predict the survival probability of juvenile individuals in a disease landscape thereby representing an exciting prospect for the field of conservation reintroduction biology. Interactions among indices of immune function are investigated at the individual level for Mauritius parakeets and also at the species level with the sympatrically occurring and non-native Indian ringneck parakeet (Psittacula krameri). Patterns of species-level genetic diversity of the Mauritius parakeet spanning two decades are examined and interspecies variation in immune function and genetic diversity is explored. Productivity and survival of Mauritius parakeets is summarised during and after a disease outbreak and an in depth analysis of the predictors of infection status and immunocompetence in this species is offered. This study highlights the complexity of the immune system and the challenges faced when trying to characterise it among individuals in an ecological context. I reveal a declining trend in species-level genetic diversity among Mauritius parakeets due to low natural dispersal demonstrating the importance of adaptively managing endangered species. I illustrate how, as a result of population bottlenecks or contrasting evolutionary histories that the Mauritius parakeet displays an attenuated immune function when compared to the Indian ringneck parakeet. I find no evidence to suggest that genetic diversity or inbreeding predicts disease infection in Mauritius parakeet nestlings and finally I use long-term monitoring data to cherry pick suitable individuals for reintroduction.
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Burns, Fiona E. "Conservation biology of the endangered St. Helena Plover Charadrius sanctaehelenae." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544502.
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Oceanic islands contribute significantly to global biodiversity due to the high levels of endemism they exhibit. Many island species have, however, become extinct following the arrival of humans, and many others remain threatened. This thesis focuses on one of these threatened island species; the St. Helena Plover, Charadrius sanctaehelenae. The objectives of my PhD were threefold: to understand the current status of the St. Helena Plover, to investigate aspects of its environment that may threaten its persistence, and to compare conservation options. Observational data were used to understand how variation in the environment influences the plover’s distribution and demography. This information was used to inform a controlled trial investigating the use of nest exclosures as a way to improve productivity. New understanding of the species’ population ecology was brought together to create a stochastic meta-population model. This model was used to understand the influence of demographic and life history parameters on the population growth rate and to compare alternative conservation options. Indicators of the future status of the St. Helena Plover population appear mixed; with numbers predicted to decline slowly, but with a high chance of species persistence over the timeframe simulated, 50 years. Nest predation by introduced species, predominately cats, was predicted to suppress nest survival and bring productivity at some sites below that required for population stability. The use of nest exclosures did not increase nest survival and led to a decrease in adult survival. Habitat characteristics were more important in determining the species distribution than influencing its demography. The plovers appeared to select breeding habitat to maximise the visibility from the nest and the accessibility of invertebrate prey. Simulations suggested that predator control would have a large beneficial effect on the population growth rate and that concurrent habitat improvement would have greater than additive benefits. Targets for conservation management include Deadwood Plain; predator control as this key site was predicted to lead to the largest increase in the overall population growth rate, and Man and Horse; there may be potential at this site to increase adult survival, which was found to be the most influential demographic parameter.
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Cook, Emily Louina. "Measuring and Developing Ecological Literacy to Conserve the Critically Endangered." Thesis, Prescott College, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10813561.
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The Mariana crow (Corvus kubaryi), locally and henceforth in this document called Aga, is a critically endangered species endemic to two Northern Mariana Islands. Aga are extirpated (locally extinct) on Guam but still persist on Rota. Multiple studies calculate a 93%–95% population decline over thirty years, with a recent estimate of 170 Aga on Rota. The primary reason for the decline on Rota is unknown, though predation by introduced mammals, habitat loss, and harassment are likely. The majority of research concerning Aga is in the biological sciences. The only social science survey conducted on Rota regarding Aga revealed that the majority of adult residents condone harassing Aga; yet, knowledge amongst Rota's inhabitants about bird ecology in general remains low, and youth residents were not surveyed. My study developed and implemented an avian-focused environmental education curriculum intended to increase ecological literacy, and evaluated the curriculum using social science research methods. My curriculum was based in storytelling, kinetic activities, and place-based education. I collaborated with local teachers to align the 5-lesson curriculum to science standards. Pre- and post-surveys were conducted with 18 control and 18 treatment students to gauge knowledge and attitudes in elementary students on Rota. Formative evaluations were also used to understand the preferred learning styles of students. Overall, students displayed some improvement in their avian ecological knowledge and positive attitudes towards Aga, and the treatment group improved in bird identification. Students in the treatment group increased their Aga identification by 38.8%. Notable for the treatment group, 23.5% of students thought it was okay to chase Aga in the pre-survey, yet 0% thought it was okay to in the post-survey. To save Aga from extinction, long-term environmental education initiatives are needed to raise ecological literacy, increase appreciation of these birds, and empower citizen science efforts on Rota.
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Thomas, Gethin Rhys. "Conservation ecology of the endangered freshwater pearl mussel, Margaritifera margaritifera." Thesis, Swansea University, 2011. https://cronfa.swan.ac.uk/Record/cronfa43091.
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The general aim of this thesis was to examine the merits of ex-situ vs. in-situ strategies for the conservation of the endangered freshwater pearl mussel, Margaritifera margaritifera, and to investigate the relationship of the larval parasitic stages of the mussel (glochidia) with the salmonid hosts. To this end, I critically reviewed the literature on conservation of freshwater mussels, developed methods for quantifying the behaviour and activity patterns of adult mussels in captivity, experimentally studied host specificity, and quantified the physiological and behavioural effects of glochidia upon salmonid hosts. The results indicate that the conservation of the freshwater pearl mussel is probably best addressed at the watershed scale, and will benefit from a combination of ex-situ and in-situ techniques, as well as from a more critical assessment of findings, many of which are only reported in the grey literature. Empirical, peer-reviewed data are badly needed to inform current conservation efforts. Novel Hall-effect magnetic sensors were used to quantify and characterise discrete mussel behaviours without adversely affecting the welfare or survival of adult mussels, and these hold considerable potential for determining optimal rearing conditions for ex-situ conservation. Arctic charr was shown to be a potentially suitable host for M. margaritifera, and occupied an intermediate position in host suitability between brown trout and Atlantic salmon. Physiological impacts of glochidia upon brown trout included swelling of secondary lamellae and spleen enlargement, but the latter tended to be slight and was restricted to 1 month post-exposure. Glochidia encystment had no significant effect on blood haematocrit, respiratory performance, or cryptic colouration of brown trout hosts. The behavioural effects were more subtle and glochidiosis made brown trout more risk-averse and less willing to explore a novel habitat, without affecting the host's ability to chemically recognise and avoid cues from a predator. Overall, the results of this thesis indicate that the impacts of glochidia upon salmonid hosts are probably slight and temporally variable, and may perhaps lead to increased host survival, which would support the symbiosis-protocooperation theory of glochidia-salmonid interaction.
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Wilson, Maya. "Biology and conservation of the endangered Bahama Swallow (Tachycineta cyaneoviridis)." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/96264.
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In order to prevent species extinctions, conservation strategies need to incorporate the identification and mitigation of the root causes of population decline with an assessment of vulnerability to genetic and stochastic factors affecting small populations. Species or populations with small ranges, such as those on islands, are particularly vulnerable to extinction, and deficient knowledge of these species often impedes conservation efforts. The Bahama Swallow (Tachycineta cyaneoviridis) is an endangered secondary cavity-nester that only breeds on three islands in the northern Bahamas: Abaco, Grand Bahama, and Andros. I investigated questions related to population size and distribution, genetic diversity and population structure, breeding biology, and ecological interactions of the swallow, with the goal of informing the conservation and management of the species. Using several population survey methods on Abaco, I found that swallow site occupancy and density is higher in southern Abaco, especially near roads and pine snags. Future research should prioritize identifying the causes of variable and low population densities in parts of the swallow's range. I used microsatellite markers and morphometrics to assess differences between populations on Abaco and Andros. We found a lack of genetic differentiation (G'ST = 0.03) between populations, but differences in morphology suggest that gene flow might be low enough to enable traits under selection to diverge. By locating and monitoring nests, I found that swallows rely on woodpecker-excavated cavities in pine snags and utility poles, and that swallows nesting in pine snags had higher fledging success (92%) than those nesting in utility poles (50-62%). Using a cavity nest-web approach, I assessed how swallows interact with cavity-nesting birds and resources on Abaco. Hairy Woodpeckers (Dryobates villosus) primarily excavated pine snags, while West Indian Woodpeckers (Melanerpes superciliaris) excavated utility poles in non-pine habitat. Only swallows and La Sagra's Flycatchers (Myiarchus sagrae) used nest sites in the pine forest. Swallows in non-pine habitat face competition for cavities with American Kestrels (Falco sparverius), and non-native House Sparrows (Passer domesticus) and European Starlings (Sturnus vulgaris). These results highlight the importance of pine forest and the Hairy Woodpecker for the persistence of the swallow.Doctor of Philosophy
In order to prevent species extinctions, conservation strategies need to identify and resolve the problems that cause species to decline, as well as address issues characteristic of small populations. Species or populations with small ranges, such as those on islands, are particularly vulnerable to extinction, and lack of knowledge of these species often impedes conservation efforts. The Bahama Swallow is an endangered species that only breeds on three "pine islands" in the northern Bahamas. The swallow is a secondary cavity-nester, which means that it nests in a cavity, usually either a natural tree hole or a hole created by another bird species. In this study, I investigated where swallows are found on the islands, the genetics and body sizes of populations, nesting biology, and connections with other species, with the goal of providing information for the conservation and management of the species. On Abaco, I found that there are more swallows in the southern part of the island, especially near roads and the dead standing pine trees (pine snags) used for nesting. Future research should assess why there are fewer birds in other parts of the swallow's range. I tested whether the genetics and body sizes of populations on Abaco and Andros are different from each other. Populations were genetically similar, but may be separated enough to result in body size differences. I located swallow nests on Abaco, and found that swallows rely on cavities made by woodpeckers in pine snags and utility poles. By visiting some nests repeatedly, I found that swallows nesting in pine snags were more successful than those nesting in utility poles. I also assessed how swallows interact with the other bird species that create and use nesting cavities. Hairy Woodpeckers usually create cavities in pine snags, while West Indian Woodpeckers use utility poles outside of the pine forest. Swallows nesting in the pine forest compete with fewer bird species for cavities than swallows nesting in other habitats. These results show that managing the forest to retain pine snags and Hairy Woodpeckers is important for the conservation of the swallow.
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Ortmann, Heinz. "Conserving Wilkins' Bunting (Nesospiza wilkinsi): an endangered, single island endemic." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/4758.
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Ivey, Kathleen N. "Thermal Ecology of the Federally Endangered Blunt-nosed Leopard Lizard." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2143.
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Recognizing how climate change will impact populations can aid in making decisions about approaches for conservation of endangered species. The Blunt-nosed Leopard Lizard (Gambelia sila) is a federally endangered species that, despite protection, remains in extremely arid, hot areas and may be at risk of extirpation due to climate change. We collected data on the field-active body temperatures, preferred body temperatures, and upper thermal tolerance of G. sila. We then described available thermal habitat using biophysical models, which allowed us to (1) describe patterns in lizard body temperatures, microhabitat temperatures, and lizard microhabitat use, (2) quantify the lizards’ thermoregulatory accuracy, (3) calculate the number of hours they are currently thermally restricted in microhabitat use, (4) project how the number of restricted hours will change in the future as ambient temperatures rise, and (5) assess the importance of Giant Kangaroo Rat burrows and shade-providing shrubs in the current and projected future thermal ecology of G. sila. Lizards maintained fairly consistent daytime body temperatures over the course of the active season, and use of burrows and shrubs increased as the season progressed and ambient temperatures rose. During the hottest part of the year, lizards shuttled among kangaroo rat burrows, shrubs, and open habitat to maintain body temperatures below their upper thermal tolerance, but occasionally, higher than their preferred body temperature range. Lizards are restricted from staying in the open habitat for 75% of daylight hours and are forced to seek refuge under shrubs or burrows to avoid surpassing their upper thermal threshold. After applying climatic projections of 1 and 2˚C increases to 2018 ambient temperatures, G. sila will lose additional hours of activity time that could compound stressors faced by this population, potentially leading to extirpation.
Finally, temperature-based activity estimation (TBAE) is an automated method for predicting surface activity and microhabitat use based on the temperature of an organism and its habitat. In an attempt to lessen impacts on sensitive species and costs, we assessed continuously logged field active body temperatures as a tool to predict the surface activity and microhabitat use of an endangered lizard (Blunt-nosed Leopard Lizard, Gambelia sila). We found that TBAE accurately predicts whether a lizard is above or below ground 75.7% of the time when calculated using air temperature, and 60.5% of the time when calculated using biophysical models. While surface activity was correctly predicted about 93% of the time using either method, accuracy in predicting below ground (burrow) occupancy was 62% for air temperature and 51% for biophysical models. Using biophysical model data, TBAE accurately predicts microhabitat use in 79% of observations in which lizards are in the sun, 47% in the shade, and 51% in burrows. Heliotherms bask in the sun, and thus body temperatures can shift rapidly when the animal moves to a new microhabitat. This sensitivity, makes TBAE a promising means of remotely monitoring animal activity, particularly for specific variables like emergence time and surface activity.
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Sommers, Mark S. "Let wildlife live : a computer illustrated calendar of endangered species /." Online version of thesis, 1993. http://hdl.handle.net/1850/11970.
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Grant, Marissa Catherine Jernegan. "Survival strategies of the endangered Physaria ludoviciana (silvery bladderpod; Brassicaceae) /." View online, 2009. http://repository.eiu.edu/theses/docs/32211131592147.pdf.
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Lee, Tim. "The behavior of endangered populations in a randomly fluctuating environment /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Lo, Chau-Yee. "Endangered species : the harpsichord and its new repertoire since 1960." Thesis, University of Leeds, 2004. http://etheses.whiterose.ac.uk/430/.
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The twentieth-century harpsichord has an unusual history: coming out of oblivion at the end of the nineteenth century, it was given a new lease of life, but at the same time acquired a mistaken identity. This thesis examines, from the perspective of the harpsichordist, the two types of harpsichord prominent in the musical mainstream in the twentieth century, and specific pieces written for both between 1960 and 1990. The two types of instrument under discussion are (1) the modern pedal harpsichord modelled after the instrument tailor-made for Wanda Lartdowska and (2) the historical instrument which emerged and proliferated in the latter part of the twentieth century. In particular it focuses on the two different types of music composed for the two instruments, starting with Maurice Ohana's Carillons pour les heures du jour et de la nuit (1960), written for the modern pedal harpsichord, through Gyorgy Ligeti's Continuum (1968), also written for the pedal instrument, to two ensemble pieces including the historical harpsichord: Chiel Meijering's n'Dame scheert haar benen (1981) for harpsichord and guitar, Ton Bruynes Schrootsonate (1990) for harpsichord and soundtracks, and Iannis Xenakis's Khoar, for the modern pedal instrument. Finally, it examines Elliott Carter's Double Concerto for Harpsichord and Piano with Two Chamber Orchestras (1961), the most elaborate harpsichord work to date. The detailed analyses encompass a flexible but consistent methodology, drawing on the experience of the performer to elucidate the different ways different composers have related to the different characteristics of the two types of harpsichord. The thesis concludes by summarising the development of harpsichord repertoire from 1960, making inferences from the foregoing discussion, and commenting on the possibility of continuing development of harpsichord repertoire in the twentieth-first century.