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Pearch, Malcolm J. "Small mammal biodiversity in Nepal." Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until June 2, 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26193.
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Freshley, Megan Elizabeth. "Hey Mammal." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1784.
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This collection of poems is representative of the creative writing and literary studies completed during my time in Portland State University's Master of Fine Arts Program. Poetry workshops, seminars in prosody, syntax, and translation, and forays into the magic of rhetoric and defamiliarization in the novel have all contributed to the thinking and feeling shown in this work. Some themes that the collection circles around are: the alienating and sometimes ecstatic relationship between the identities of civilized human and human-as-animal, the processes of falling in and out of faith in a greater power and with belonging to a human community, non-binary and unconventional performances of gender and sexuality, psychological inquiry about the nature of the self, the cleaving of mind and body, and meditations on 21st Century youth.
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Wong, Dorothy L. "Public perception of mammals and mammal conservation in Fairfax County, Virginia." Fairfax, VA : George Mason University, 2009. http://hdl.handle.net/1920/4588.
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Thesis (M.S.)--George Mason University, 2009.Vita: p. 160. Thesis director: E.C.M. Parsons. Submitted in partial fulfillment of the requirements for the degree of Master of Science in Environmental Science and Policy. Title from PDF t.p. (viewed Oct. 11, 2009). Includes bibliographical references (p. 152-159). Also issued in print.
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Klanjšček, Tin. "Dynamic energy budgets and bioaccumulation : a model for marine mammals and marine mammal populations." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34623.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2006."June 2006."
Includes bibliographical references.
Energy intake of individuals affects growth of organisms and, therefore, populations. Persistent lipophilic toxicants acquired with the energy can bioaccumulate and harm individuals. Marine mammals are particularly vulnerable because of their large energy requirements, and transfer of energy and toxicants from mothers to their young during gestation and lactation. Dynamic energy budget (DEB) models for energy assimilation and utilization, coupled with pharmacokinetic models that calculate distribution of toxicants in individuals, can help investigate the vulnerability. In this dissertation I develop the first individual DEB model tailored specifically to marine mammals and couple it to a pharmacokinetic model for lipophilic toxicants. I adapt the individual model to the right whale and use it to analyze consequences of energy availability on individual growth, reproduction, bioaccumulation, and transfer of toxicants between generations. From the coupled model, I create an individual-based model (IBM) of a marine mammal population. I use it to investigate how interactions of food availability, exposure to toxicants, and maternal transfer of toxicants affect populations. I also present a method to create matrix population models from a general DEB model to alleviate some of the drawbacks of the IBM approach.
by Tin Klanjšček.
Ph.D.
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Pereira, Patrícia de Sousa. "Characterization of mammal salivary peptides." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10135.
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Mestrado em BioquímicaA saliva e os seus componentes desempenham diversas funções na cavidade oral, tais como lubrificação, proteção dos tecidos orais e ação antimicrobiana. Entre os componentes responsáveis por esses papéis estão diversos péptidos cuja evolução e presença na saliva de outras espécies de mamíferos não está clara. No presente trabalho, duas classes destes péptidos, as cistatinas salivares e a timosina β4, foram analisadas usando ferramentas de genómica e de proteómica em conjunto. Para os estudos de proteómica foi colhida saliva de cão, rato, coelho e cordeiro, sendo a separação dos péptidos presentes feita por cromatografia liquida e a análise por espectrometria de massa tandem. Para os estudos de genómica foram pesquizadas bases de dados de sequências nucleotídicas e realizaram-se análises evolutivas. No que diz respeito à timosina β4 demonstrou que este péptido apresenta uma elevada conservação entre as diferentes espécies de mamíferos. Utilizando as sequências deste péptido encontradas no genoma dos diferentes mamíferos, foi possível identificar pela primeira vez por espectrometria de massa a timosina β4 na saliva do cão. No caso da classe das cistatinas, nomeadamente cistatinas C, D e tipo-S (S, SA e SN), a análise evolutiva permitiu verificar que as cistatinas D e tipo-S são específicas dos primatas, o que sugere que terão emergindo após a grande separação dos mamíferos que ocorreu há cerca de 80-90 milhões de anos. Os resultados permitiram também verificar que algumas sequências presentes nas bases de dados encontram-se mal anotadas, incluindo a sequência atribuída à cistatina S encontrada no rato. Por outro lado, a análise filogenética demonstrou que a cistatina C está distribuída por várias classes de mamíferos. No entanto, permanece por compreender o mecanismo da sua secreção na saliva humana e a sua ausência na saliva de outras espécies de mamíferos. Em conclusão, através da combinação da proteómica e filogenia podemos caracterizar e compreender a distribuição dos péptidos salivares em diferentes mamíferos e comparar com toda a informação existente para a saliva humana.
Saliva and its components play several roles in the oral cavity, such as lubrication, protection of tissues and antimicrobial action. Among the components responsible for these roles are several peptides, which evolution and presence in other mammals’ saliva is not clear. In the present study, two peptide classes, salivary cystatins and thymosin β4, were analyzed using a combination of genomic and proteomic tools aiming the enlightening changes in the structure and distribution of these peptides between the different mammal species. For the proteomic analysis, saliva was collected from dog, rat, rabbit and lamb, being salivary peptides separated by chromatography and analyzed by tandem mass spectrometry. For the genomic studies, database of nucleotide sequences were searched and evolutionary analyses were performed. Regarding thymosin β4, the evolutionary analysis showed that this peptide is highly conserved through the collection of all peptide sequences from different mammals species genome, it was possible to identify for the first time by mass spectrometry the thymosin β4 in dog’ saliva. Respecting cystatins class, namely C, D and S-type cystatins (S, SA and SN), evolutionary analysis showed that D and S-type cystatins are Primate specific, which suggesting that these classes emerged after the great mammalian radiation at 80-90 million years ago. The results also showed errors in the annotation of these sequences in databases, in particular the sequence attributed to cystatin S detected in rat. In contrast, evolutionary analysis showed that cystatin C is widely distributed in several mammal classes. However, it is not clear their secretion mechanism to saliva and why its absence in saliva of other mammal’ species. In conclusion, using phylogenetic and proteomic approaches it will be possible to understand and characterize the distribution of these peptides in different mammal species and compare with what is known in the human saliva.
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Klug, Kevin Joseph, Sean Rice, Ina Kundu, Hao Chen, Elizabeth Marquez, and Yizhou Zhong. "Lightweight Small Mammal GPS Tracker." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/297660.
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A position beaconing system for tracking small mammals, such as the Golden Lion Tamarin, was developed and tested. GPS acquires location of the animal. The system utilizes a VHF radio transmitter tuned to 144.390 MHz, which is located in the amateur radio band. APRS was selected as the protocol for position, transmission, and recovery. This allows users to benefit from any existing APRS enabled devices. The beacon was designed by attempting to optimize operational longevity and minimize size. Consequently, the system is implemented on a single board and enclosed for protection. As the system must be comfortable for the mammal, it was manufactured from lightweight components and enclosed in plastic housing. To attach the case to the mammal, it is connected to a flexible, zig-zag, wearable antenna, which functions as a collar.
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Kundu, Ina Annesha, Kevin Joseph Klug, Sean Rice, Hao Chen, Elizabeth Marquez, and Yizhou Zhong. "Lightweight Small Mammal GPS Tracker." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/297636.
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A position beaconing system for tracking small mammals, such as the Golden Lion Tamarin, was developed and tested. GPS acquires location of the animal. The system utilizes a VHF radio transmitter tuned to 144.390 MHz, which is located in the amateur radio band. APRS was selected as the protocol for position, transmission, and recovery. This allows users to benefit from any existing APRS enabled devices. The beacon was designed by attempting to optimize operational longevity and minimize size. Consequently, the system is implemented on a single board and enclosed for protection. As the system must be comfortable for the mammal, it was manufactured from lightweight components and enclosed in plastic housing. To attach the case to the mammal, it is connected to a flexible, zig-zag, wearable antenna, which functions as a collar.
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Rice, Sean Christopher, Kevin Klug, Ina Kundu, Sean Rice, Hao Chen, Elizabeth Marquez, and Yizhou Zhong. "Lightweight Small Mammal GPS Tracker." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/297746.
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A position beaconing system for tracking small mammals, such as the Golden Lion Tamarin, was developed and tested. GPS acquires location of the animal. The system utilizes a VHF radio transmitter tuned to 144.390 MHz, which is located in the amateur radio band. APRS was selected as the protocol for position, transmission, and recovery. This allows users to benefit from any existing APRS enabled devices. The beacon was designed by attempting to optimize operational longevity and minimize size. Consequently, the system is implemented on a single board and enclosed for protection. As the system must be comfortable for the mammal, it was manufactured from lightweight components and enclosed in plastic housing. To attach the case to the mammal, it is connected to a flexible, zig-zag, wearable antenna, which functions as a collar.
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Kundu, Ina, Sean Rice, Kevin Klug, Hao Chen, Elizabeth Marquez, and Yizhou Zhong. "Collar-Integrated Small Mammal GPS Tracker." International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579699.
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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NVA position beaconing system for tracking small mammals, such as the Golden Lion Tamarin, was developed and tested. GPS acquires location of the animal. The system utilizes a VHF radio transmitter tuned to 144.390 MHz, which is located in the amateur radio band. APRS was selected as the protocol for position, transmission, and recovery. This allows users to benefit from any existing APRS enabled devices. The beacon was designed by attempting to optimize operational longevity and minimize size. Consequently, the system is implemented on a single board and enclosed for protection. As the system must be comfortable for the mammal, it was manufactured from lightweight components and enclosed in a plastic housing. To attach the case to the mammal, it is connected to a flexible, zig-zag, wearable antenna, which functions as a collar.
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Clements, Michelle N. "Phenology in a wild mammal population." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/14599.
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Meek, Sarah. "Small mammal pollination in Protea Witzenbergiana." Bachelor's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/25926.
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Protea witzenbergiana possesses some features common to that of therophilous Proteas in the Cape Floristic Region, such as a cup-shaped, downwards-hanging inflorescence surrounded by red involucral bracts, which emits a yeasty, musky odour. The flowering season occurs in the winter and the plants occur in small, localized and isolated stands in the Witzenberg fynbos. However, the species has never been investigated as to whether it is pollinated by small mammals. This study investigated whether the plant is rodent-pollinated, and if so to what extent by various species. Fieldwork was carried out over three days of live trapping, during and after the flowering season. Exclosure experiments were set up in order to assess seed set. Mammal droppings were collected, processed and pollen grains were counted. All small mammal species excepting one (Otomys irroratus) contained pollen grains in their faeces. Oendromus melanotis, Mus minutoides and Aethomys namaquensis were found to be the most important pollinators. The small mammal community showed a distinct change in size and composition after flowering season had ended, suggesting that the availability of nectar resources may be an important food supply to small mammals in the area. Implications of these findings could be relevant for conservation and co-evolutionary studies.
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Fraser, Sheena Mary. "Mammals in Late Neolithic Orkney (with reference to mammal bone recovered from Links of Noltland, Westray)." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/26007.
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Excavation of thirty skulls, twenty-eight cattle and two sheep from the foundation course of a Late Neolithic structure at Links of Noltland (LON), Structure 9, is the starting point for this thesis, which investigates the economic and socio-cultural relationships of cattle and other mammals on Orkney communities between 3000 and 2500 BC. The LON settlement was located on a machair plain in Westray, the most N-W island within the Orkney archipelago (HY 428 493). Male and female cattle skulls were inter-mixed within the LON foundation course so a “bull cult” is not represented. The sequence from living skulls to skulls “animating the building is (i) breed/acquire (ii) nurture (iii) cull/butcher (iv) consume (v) transform to object (vi) curate (vii) deposit. A skull deposit infilling an internal passageway from another LON, Structure 18, is compared and contrasted with the Structure 9 foundation deposit. Special treatment of cattle skulls from a wide range of European and Near-East sites is also reviewed to emphasise the widespread use of this symbol during the Neolithic period. Orkney was separated from mainland Scotland prior to the establishment of the LON settlement so consideration is given to modes of arrival for mammals and their impact on this depauperate archipelago. Cattle and sheep dominated the domestic mammal remains examined, pig and dog were rare and goat and horse absent. The most abundant non-domestic mammals were red deer and Orkney voles, but otters and sea mammals were also present in low numbers. Genetic studies indicate that one cattle skull carried genetic material from aurochs, wild cattle. To date there is sparse evidence of interbreeding between wild aurochs and Neolithic domesticated cattle in Europe and none in Britain. The alterative explanation that aurochs were already present on Orkney during the Neolithic is explored. Articulated red deer deposits from LON were also examined. Although previous publications explored the possibility that these deposits are “ritual” other possible explanations for these deposits are outlined. No parallels were noted between the cattle skull and articulated red deer deposits, but the importance of antler for practical and symbolic use in Neolithic Orkney may be under-estimated. Stature of cattle remained relatively stable during the Mid to Late Neolithic in Orkney but underwent diminution by the Iron Age. A similar, but less marked reduction was also noted for sheep, but red deer already had small stature compared with early Holocene mainland Scotland red deer. The thesis concludes that cattle, sheep and red deer were of fundamental importance to the Neolithic society of Orkney, providing surplus food, tools and possibly traction, to support an increasingly sophisticated Neolithic society undertaking construction of complex structures and monuments. In addition, cattle fulfilled an important role in their cultural and spiritual life.
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McCaslin, Lauren E. "Documenting Marine Mammal Behavior and Evaluating the Benefits and Consequences of Viewing Marine Mammals in Southcentral Alaska." TopSCHOLAR®, 2019. https://digitalcommons.wku.edu/theses/3128.
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Marine mammals are in a precarious conservation position because of anthropogenic impacts and historic perceptions that they are a consumable commodity. In light of changing abiotic conditions, further evaluation is needed on the habitat use, behavior, and interactions among marine mammals. Conservation legislation has helped protect species, but the greatest ground swelling may be the advent of the commercial whale watching industry. The feeding grounds in Alaskan waters have made this area a prime tourism location, and these nutrient-rich waters have resulted in a confluence of marine mammal species, including the appealing and abundant humpback whale (Megaptera novaeangliae) that may associate with three ecotypes of killer whales (Orcinus orca). These species are interesting because they may travel together to feed on prey or be adversaries in a predator-prey relationship. Using whale watching as a platform, this study evaluated the effects of the presence of these two species separately and together, and of the type of interaction between them, on human perception. Data were collected via opportunistic observations and a retrospective pre- and post-survey instrument. Differences in humpback whale distribution and group size patterns were found relative to killer whale occurrence, although humpback whale behavioral states were unchanged. Changes in passenger conservation attitudes could not be attributed to species and behaviors but they were important determinates to whale watching satisfaction. Overall, more positive conservation attitudes and an increase in knowledge about marine mammals were reported after whale watching. These tours provide an opportunity for collecting meaningful scientific data and providing more in-depth education such as enhancing the appreciation for ecosystem services provided by marine mammals.
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Hall, Amy Louise. "Small mammal movement patterns in habitat mosaics." Thesis, University of York, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399622.
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Van, Pletzen Liezl. "The large mammal fauna from Klasies River." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51991.
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Thesis (MPhil)--University of Stellenbosch, 2000.ENGLISH ABSTRACT: The large mammal faunal sample, excavated since 1984 from the Late Pleistocene Klasies River main site, was studied. There are 27 species in eight genera represented. The bovids from the LBS member (110 000 years) and the Upper member (70 000 years) shows an increase in grazers relative to the fauna from the SAS member (100 000 years). This confirms previous research. The study of body part frequencies does not confirm the selective transport of the carcasses of larger bovids or that scavenging played an important role in the accumulation of the fauna. It is concluded that availability of marine mammals were the attraction of the locality and that all size classes of bovids were actively hunted and their carcasses returned to the site. KEYWORDS: Klasies River, Late Pleistocene, large mammal fauna, hunting.
AFRIKAANSE OPSOMMING: Die groot soogdier fauna van die Laat Pleistoseen vindplaas Klasies River main site, opgegrawe vanaf 1984, is bestudeer. Sewe-en-twintig spesies in agt genera is verteenwoordig. Die bokke van die LBS member (110 000 jare) en die Upper member (70 000 jare) toon 'n styging in grasvreters relatief tot dié van die SAS member (100 000 jare). Dit bevestig 'n vorige ondersoek. Die bestudering van ligaamsdeel frekwensies van alle groottes bokke bevestig nie dat selektiewe vervoer van groter bokkarkasse plaasgevind het nie, of dat aas 'n rol in die akkumulasie van die fauna gespeel het nie. Die gevolgtrekking is gemaak dat die teenwoordigheid van marine soogdiere die rede was vir die keuse van hierdie vindplaas was. Alle groottes bokke is doelbewus gejag en hulle karkasse is teruggebring na die vindplaas. SLEUTELWOORDE: Klasies River, Laat Pleistoseen, groot soogdiere, jag.
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Kuhn, Nicola. "Community ecology of small-mammal pollinated proteas." Bachelor's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/14252.
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The floral characteristics of small-mammal pollinated (SMP) Protea species have been assessed in a number of previous studies. This study aimed to determine whether the inflorescences of Protea canaliculata, Protea sulphurea and Protea humiflora possess these traits and are pollinated by small mammal species. An additional aim of this study was to determine whether there is a variation in pollinator efficiency of different animal species. Floral characteristics that may influence plantpollinator interactions were measured, including floral dimensions, nectar production and spectral reflectance. Live-trapping was conducted using Sherman traps and mean facial and faecal pollen load was determined for the different species caught. Furthermore pollinators were observed through footage from motion sensor cameras placed facing the inflorescences of SMP proteas. The results of this study confirmed that Protea canaliculata, Protea sulphurea and Protea humiflora are pollinated by small mammal pollinators. The evidence supporting this is that the afore-mentioned species have traits that correspond to those possessed by known small-mammal pollinated proteas including: bowlshaped inflorescences, high nectar concentrations (ranging between 24.1-42.9%), sucrose-rich nectar composition, a "yeasty" scent, floral colours that are visible to small mammals, and a winter flowering season. These proteas were found to have separated peak flowering times, providing a nectar source throughout winter for small mammals at this site. Fifty-eight small mammals of seven different species, were trapped in P. canaliculata and P. sulphurea stands over 98 hours. The average nighttrapping success was 22.7% and day-trapping success was 5.7%, indicating a relatively abundant nocturnal small-mammal population. A separation in pollinator efficiency was observed for different small mammal species, with Elephantulus edwardii identified as the most effective pollinator as it showed the greatest pollen removal (highest faecal pollen load) and spent the longest time foraging on inflorescences (±28 seconds per inflorescence). Another important pollinator was Aethomys namaquensis because it visited flowers 75% more frequently than any of the other pollinators. Camera trapping was shown to be a superior method than conventional trapping for assessing pollination by providing insight into pollinator behaviour, identifying new pollinators of 'trap-shy' species and also due to its more animal-friendly disposition.
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Durban, John William. "Bayesian methods for marine mammal population assessment." Thesis, University of Aberdeen, 2002. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602316.
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Policy-makers increasingly need to use scientific data that are imprecise. This problem is particularly apparent for marine mammal management issues, where practical research constraints leave scientists and managers with the problem of drawing inference from sparse data. Effective use of such data therefore places great demands on our methods of data analysis and statistical inference. In this thesis I introduce novel Bayesian methods for the analysis of data on marine mammal abundance and trends. Bayesian methods are applied to a suite of case studies to inform current management issues of importance both in the UK and overseas. These include estimating the probability of density dependence in the growth of a killer whale (Orcinus orca) population inhabiting the inshore waters of Washington State; estimating the size of a widespread population of bottlenose dolphins (Tursiops truncatus) in the Bahamas; and assessing the population status and abundance trends of bottlenose dolphins within a newly designated Special Area of Conservation in the Moray Firth, NE Scotland. Each of these case studies uses model-based analysis of individual photo- identification data to make inference about unknown population parameters of interest. Specifically, Bayesian inference, based on "posterior" probability distributions and statements, is used to facilitate scientific reporting in the face of uncertainty about these unknowns. Additional issues addressed are the selection of alternative statistical models for inference based on posterior model probabilities; incorporating model selection uncertainty into inference through the estimation of model-averaged parameter estimates; and the use of random effects prior distributions to model the relatedness between unknown parameters and increase estimate precision. The application of these methods is accomplished through the use of Markov chain Monte Carlo sampling methods, which are implemented using the WinBUGS software.
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Hulme, Philip Eric. "Small mammal herbivory and plant recruitment in grassland." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46352.
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Ecke, Frauke. "Effects of landscape patterns on small mammal abundance." Doctoral thesis, Luleå, 2003. http://epubl.luth.se/1402-1544/2003/30/index.html.
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Linderhed, Anna. "Marine mammal behavior response to sonars, a review." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97226.
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During the last decades the problems caused by anthropogenic sound and noise in oceans have been recognized in public, by governments, and military. With the use of active sonar, different choices can be made to minimize the risk of damaging or disturbing marine mammals. For this purpose knowledge of sonar disturbance is crucial. There are methods for time or area planning, i.e. when and where to use active sonars, to avoid marine mammals. The purpose of this work is to find information in literature on marine mammal behaviour reactions to the sound of sonar pings, and to evaluate which of two different behavioural models used in risk assessment programs, the “varying response” model and the “avoidance” model, is more correct to use. Main focus is on sonars and marine mammals residing in Sweden, i.e. the harbour porpoise, grey seal, harbour seal and ringed seal. Behavioral results from other research areas such as bycatch, environmental, and strandings, together with other sound sources than sonars and other species, provide a broader picture of the situation in noisy oceans. For the harbor porpoise the “avoidance” model works well. It is a very shy species, which flees fast and far when it comes in contact with new things. With the seals however the “avoidance” model is probably less good, since their responses to sonar differ rather much. Hence, for these taxa we recommend to use the “various” model that takes into account such varying responses.
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Cuaron, Alfredo D. "Land-cover changes and mammal conservation in Mesoamerica." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368617.
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Perkovich, Cynthia L. "Responses of oaks to mammal and insect herbivory." Kent State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=kent1619098714170774.
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Berens, Jeffrey David. "Morphological Differences and Diversity of Small Mammal Species." Thesis, North Dakota State University, 2016. https://hdl.handle.net/10365/27710.
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Small mammals play important roles in ecosystems, but are often overlooked due to their small size and plentiful abundance. Two studies evaluated the morphological differences and diversity of small mammal species based on how they react to different environmental conditions. The first study analyzed the morphological differences of skulls between and within two species of Peromyscus species due to differences in shape, size, and geographic position. This study also determined if landmark-based geometric morphometrics could reliably discriminate between the two species. The second study analyzed small mammal diversity and abundance due to differences in microhabitat conditions in an endangered ecosystem: tallgrass prairie. Small mammals are an important food source to other vertebrate and also help regulate vegetation composition in the tallgrass prairie ecosystem. Results of both studies could help future studies identify how different variables affect small mammal morphology and diversity.
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Degrassi, Allyson Lenora. "Impacts Of Forest Disturbance On Small Mammal Distribution." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/640.
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Natural habitat in the eastern United States has diminished over the past century because of the effects of invasive species. Both plant and animal invaders can alter habitat structure and may decrease survival of native species. The degree to which an invasive species alters ecosystem function depends on the functional characteristics of affected species and the resulting cascading effects. The loss of important native species, such as foundation species, can potentially influence the structure and distribution of animal communities because of the foundation species' unique ecosystem roles. The foundation species concept is relatively new to the terrestrial ecology and the impact on animal communities resulting in the loss of terrestrial foundation species is generally unknown.
Eastern hemlock (Tsuga Canadensis), a foundation species in the eastern United States, is declining in abundance due to the invasive sap-sucking insect, hemlock woolly adelgid (Adelges tsugae, Annand). The loss of hemlock may impact the distribution and microhabitat associations of dependent species such as small mammals. I hypothesized that the distribution, population size, community composition, and microhabitat associations of small mammal species differ in response to canopy disturbance from the effects of logging and invasive species.
In this dissertation, Chapter One provides an exploration of the past research conducted on 1) invasive species and how they affect habitat structure, 2) foundation species and how they affect ecosystem function, 3) small mammal habitat associations and population cycling, 4) occupancy modeling and its usefulness and limitations in the analysis of local occupancy, colonization rates, and extinction rates. Chapter Two presents a large-scale experiment on how the hemlock woolly adelgid impacts distribution and community assembly of small mammals. Chapter Three presents how forest disturbance, food resources, and habitat structure effects local colonization and extinction patterns of southern red-backed voles. Chapter Four presents how a paper published in 2005 brought the foundation species concept to terrestrial research and how the foundation species concept can be misleading in research.
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Tsubamoto, Takehisa. "The Pondaung mammal fauna : an analysis of a terrestrial mammal fauna in the latest middle Eocene of central Myanmar (Southeast Asia)." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/150841.
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Scheidecker, Elizabeth M. "Wavelet analysis of bioacoustic scattering and marine mammal vocalizations." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Sep%5FScheidecker.pdf.
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Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, September 2005.Thesis Advisor(s): D. Benjamin Reeder, John A. Colosi. Includes bibliographical references (p. 95-97). Also available online.
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Mullins, Ruth Louise. "Characterizing marine mammal stranding events along the Texas coast." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86047.
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The Texas Marine Mammal Stranding Network (TMMSN) is a valuable data resource for the marine mammal community. Limitations of funding and personnel severely impact the ability of the Network to maintain impeccable databases. This research constructed an application to address database complications and focused on investigating the species identification, temporal and spatial trends for stranding events along the Texas coast.
From 1980 to 2004, Tursiops truncatus accounted for approximately 80% of all stranding events. The remainder was 20 additional whale and dolphin species known to reside in the Gulf of Mexico. Tursiops truncatus strand along the entire coastline and are the only species stranding in the bays. All other species stranding are most dense along the southern coastline.
The temporal scales of events revealed no linear patterns from 1980 to 2004. A unique cyclic fluctuation occurred from 1992 to 1998, including the highest yearly counts and one isolated mortality event in Port Aransas. Attempts to forecast stranding events beyond 2004 were inconclusive due to multiple factors influencing a stranding event. A bimodal seasonal trend was evident, with events peaking in the spring and fall months. Density distributions by decade isolated three frequent stranding areas: Sabine-Galveston-Brazoria counties, Galveston Shipping Channel, and Corpus Christi Shipping Channel. The final aspect analyzed spatial elaboration of events by creating six location values to describe the Texas coastline. Each event was assigned from the geographical location and the orientation of an event along the coastline. Analysis revealed the segregation of Tursiops truncatus in the bays and confirmed earlier results of density distributions. Examining the locations by time revealed a specific incident connected to a mortality event in 1992, accounting for 59% of the stranding events. Location categories were compared to the TMMSN stranding regions and the regions experienced different location frequencies.
This study demonstrated how to construct a stronger database and the necessity for database accuracy. Study conclusions demonstrated the need to better isolate and research factors responsible for event distributions in time and space along the Texas coast to forecast the magnitude and location of stranding events to better aid the TMMSN response efforts.
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Hamrick, William Wall. "Small mammal habitat associations in a fragmented agricultural landscape." Click here to access thesis, 2007. http://www.georgiasouthern.edu/etd/archive/fall2007/william_w_hamrick/hamrick_william_w_200708_ms.pdf.
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Thesis (M.S.)--Georgia Southern University, 2007."A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." In Biology, under the direction of C. Ray Chandler. ETD. Electronic version approved: December 2007. Includes bibliographical references (p. 68-74) and appendices.
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Harrison, Annabel Kate. "Dispersal and compensatory population dynamics in a harvested mammal." Thesis, University of Glasgow, 2011. http://theses.gla.ac.uk/2903/.
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Populations of wild birds and mammals are often harvested for sport, subsistence or commerce. Sustainable exploitation is an important aspect of environmental management and is critical to human wellbeing. However, our inability to sustainably harvest even well studied populations is often due to poor demographic data and a lack of understanding of critical biological processes. A key component of sustainable harvesting is the density-dependant feedback between vital rates (births, deaths, immigration and emigration) and population density, as this mechanism provides populations with the capacity to compensate for harvest mortality. The aims of this thesis are to investigate density-dependence, compensation and sustainable harvesting in a traditional Scottish quarry species, the mountain hare, Lepus timidus scoticus, using a combination of replicated field experiments, cross-sectional studies and modelling. The mountain hare has been traditionally harvested for centuries and continues to be an important source of revenue for some land owners. Over the past decade the motive for killing hares has switched from predominantly sport shooting, to culling to reduce ticks and the tick-borne disease Louping-ill virus (LIV). Louping-ill virus causes high mortality, and can supress harvest, in economically important red grouse, Lagopus lagopus scoticus. Sustainable management of the mountain hare is further complicated by cyclic, or unstable, population dynamics shown throughout their circumpolar distribution. The thesis begins with a review of the evidence that culling mountain hares can lead to a reduction in ticks and LIV prevalence, resulting in increased red grouse harvest. The empirical studies follow with the aim of providing evidence for compensatory survival and dispersal, and density-dependent reproduction. Two field study approaches were adopted; the first was a live-capture and radio-telemetry study which compared birth dates, survival probabilities and dispersal distances and rates of different age and sex classes between two populations under different harvesting regimes (harvested and non-harvested). The second empirical study used a cross-sectional design whereby population density of ten independent populations were estimated using Distance sampling, which preceded hare harvesting. Tissue samples of killed hares were collected, enabling the effects of population density on female fecundity and juvenile recruitment to be assessed. Finally, an age-structure, female-only matrix population model was parameterised using data from the empirical studies. Sustainable harvest rates were determined as the maximum harvest that produced a positive population growth rate and an extinction probability of less than 5%. By manipulating age-specific harvest and initial population size, the effects of age-biased harvest and changing population size on population viability could be investigated. Results of the cross-sectional study revealed evidence for negative density-dependent juvenile recruitment. However, this finding was not translated into compensatory survival in either juveniles or adults, although birth date of leverets was significantly later in the harvested population. Overall, dispersal distances and rates were low. Dispersal distance was greater in the harvested population, although when distance was scaled to account for differences in observation time, to give a dispersal rate, no difference was found. Projections from the matrix model suggest that 40% annual harvest rate is sustainable, although extinction probability increases with decreasing population size and as harvesting becomes increasingly yearling biased. Overall, no evidence for compensatory survival or dispersal was found, although density-dependent juvenile recruitment was identified and may be important in population persistence under exploitation. Survival and timing of breeding may be influenced by behavioural and physiological effects of harvesting, or environmental variation, which may have implications for unstable dynamics of mountain hare. I identify and discuss key areas for future research aimed at increasing our understanding of the effects of harvesting on mountain hare population dynamics and demography. In conclusion, we found little evidence that culling mountain hares can increase red grouse harvest, and therefore, cannot justify culling mountain hares for tick and LIV control. The low dispersal rates and distances, combined with limited evidence for compensatory mechanisms, imply that local blanket culls may succeed in reducing hare numbers with unknown implications for mountain hare population persistence and the wider biodiversity of the Scottish uplands.
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Severson, Jared. "Modeling and frequency tracking of marine mammal whistle calls." Thesis, Cambridge Massachusetts Institute of Technology, 2009. http://hdl.handle.net/10945/4301.
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CIVINSApproved for public release, distribution unlimited
Marine mammal whistle calls present an attractive medium for covert underwater communications. High quality models of the whistle calls are needed in order to synthesize natural-sounding whistles with embedded information. Since the whistle calls are composed of frequency modulated harmonic tones, they are best modeled as a weighted superposition of harmonically related sinusoids. Previous research with bottlenose dolphin whistle calls has produced synthetic whistles that sound too clean for use in a covert communications system. Due to the sensitivity of the human auditory system, watermarking schemes that slightly modify the fundamental frequency contour have good potential for producing natural-sounding whistles embedded with retrievable watermarks. Structured total least squares is used with linear prediction analysis to track the time-varying fundamental frequency and harmonic amplitude contours throughout a whistle call. Simulation and experimental results demonstrate the capability to accurately model bottlenose dolphin whistle calls and retrieve embedded information from watermarked synthetic whistle calls.
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Kundu, Auni, Brianne Noriega, Connor O'Brien, Corey Speros, and Dawei Ju. "Time Difference of Arrival for Small Mammal Tracking System." International Foundation for Telemetering, 2014. http://hdl.handle.net/10150/577466.
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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CAThis paper describes in depth the specifics of a tracking system for small mammals. This method is based on time difference of arrival. This project was deployed for proof of concept and demonstrates the advantages of time difference of arrival over GPS based schemes employed by previous teams.
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Hayward, Adam David. "Parasites and life history variation in a wild mammal." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5675.
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The purpose of this thesis is to investigate associations between parasite infection and host life-history variation in the wild Soay sheep population of the islands of St Kilda, NW Scotland. Studying host-parasite interactions in wild animal populations is of interest because of the importance of heterogeneity in resource availability, genetics, and environmental conditions in determining resistance to parasites, with implications for human populations and wildlife conservation and management. However, very few studies are able to investigate these associations in a longitudinal manner, which is essential in order to understand how infection is associated with life-history variation across ages and environmental conditions. In this thesis, I investigate associations between parasite resistance and ageing and the importance of maternal effects on offspring parasite resistance. I also establish the shape of natural selection on parasite resistance, and associations between measures of parasite burden and antibody responses. The principle findings of the analyses presented in this thesis are: i) Adult sheep of both sexes show a decline in parasite resistance in old age which is consistent with senescence. Furthermore, the rate of decline in parasite resistance with age is accelerated in individuals that have experienced more stressful environmental conditions over their lifespan. ii) Aspects of maternal phenotype and lamb early life performance are significantly associated with parasite resistance in lambs. Some of these effects persist into adult life and may even affect late-life changes in parasite resistance with age. iii) Analysis of ageing in five female reproductive traits shows that the contributions of individual senescence, terminal effects, and selective disappearance vary across traits, and that therefore multiple traits should be studied in order to understand ageing more fully. Most strikingly, there was no evidence for significant senescence in the probability of producing twins. iv) The first estimate of the strength of natural selection on parasite resistance in a longitudinally-monitored population provided evidence for positive selection on parasite resistance in lambs but not adults. Selection in lambs also varied across environmental conditions, being stronger in years of more favourable conditions. v) Analysis of associations between estimates of parasite burden and antibody responses showed that an estimate of parasite burden was not correlated with either a general or parasite-specific antibody response. However, antibody responses were positively correlated, and there was some evidence for a genetic correlation between the two in lambs but not adults.
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Bedington, Michael. "Drift modelling of marine mammal carcases in coastal waters." Thesis, University of the Highlands and Islands, 2015. https://pure.uhi.ac.uk/portal/en/studentthesis/drift-modelling-of-marine-mammal-carcases-in-coastal-waters(c1165a29-6c4c-4b6f-b079-e39d4ff164e5).html.
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A floating object's drift is governed by its buoyancy, shape, and the wind, waves and currents it experiences. Here, I develop a drift modelling framework for marine mammal carcases in coastal waters. The resulting models were run forwards and backwards in time to provide insights into strategies for environmental monitoring under two scenarios. The first explored the beach search options for carcases resulting from potentially fatal collisions between tidal-stream turbines and marine mammals. The second applied the reverse problem for known-location mass strandings to highlight potential at-sea mortality sites. The drift properties of carcase-like objects were assessed in at-sea experiments. Wave transport was found to be greater than Stokes drift alone and in a complex coastal area could not be represented by a downwind multiplier as many previous models have assumed. A high resolution unstructured grid wave model was set up to complement existing wind and current models for the West Coast of Scotland, and these components were combined to build a carcase drift model. In the forward case, from tidal turbine locations, the drift model showed a wide spread of potential stranding sites, suggesting monitoring a limited number of beaches is unlikely to be fruitful. However, selecting beaches in response to immediate wind direction would improve efficiency. Stranding locations alone can only provide evidence of turbine interactions if the number of animals affected is large. In the reverse case, when applied to a mass stranding in Chile, the drift model showed the ability to exclude areas of origin, even though it could not pinpoint an exact mortality site. This work advances understanding of wave transport of surface floating objects, of carcase drift modelling, and of the feasibility of strandings monitoring. The decomposition rate of carcases is a source of uncertainty in the model where further work should be undertaken.
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Ressing, Sara Marlene. "Effects of heavy metals on two small mammal species." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/theses/947.
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Research on the chronic effects of toxic chemicals on individuals, populations, communities, and ecosystems is imperative to regulate pollutants and preserve threatened species and habitats. I designed a two-pronged study to investigate the effects of heavy metal contaminants on small mammal populations, communities and body condition. To compare population and community metrics, I conducted a year-long mark-and-release study from over 5,400 trap nights on a contaminated and reference site within Crab Orchard National Wildlife Refuge, a Superfund site. During the second phase, I compared contaminant residues to body condition in 29 white-footed mice (Peromyscus leucopus) and 21 southern short-tailed shrews (Blarina carolinensis) from the Refuge and from three reference sites. Body weight, age structure, trapping success or species diversity did not differ between sites. Mice from the contaminated site were more abundant with lower reproduction (as number of juveniles per adult female). Cadmium in both livers and kidneys of mice and shrews was significantly greater on the contaminated site. Elevated renal cadmium in mice (96 ± 79 mg/kg dry weight) and shrews (242 ± 166 mg/kg dry weight) from the contaminated site could likely impair physiologic functions with long-term effects. For white-footed mice, increasing renal copper, lead, and nickel were good predictors of low ash, water, and protein but did not correlate significantly with crude lipid content. In shrews, however, metals either showed no relationship or, in the case of renal cadmium and copper were positively related to body condition as increased protein content. Simply comparing animals from reference versus contaminated sites provided few insights into overall community structure or population dynamics of white-footed mice. While metals explained as much as 40% of body condition (ash) in mice, findings in both species are counter-intuitive or refute predictions. Future studies should include manipulative field experiments that pair higher-resolution, biologic responses such as histologic and biomarker assays with population and community dynamics.
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Pennarossa, G. "CENTROSOME BIOGENESIS AND ADAPTIVE RESPONSE IN MAMMAL PARTHENOGENETIC CELLS." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/169555.
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Human parthenotes have been proposed as a source of embryonic stem cells despite the high incidence of aneuploidy described in parthenotes of most mammalian species. Through a comparative analysis between parthenogenetic and bi-parental cells lines we found that parthenogenetic cells are affected by chromosomal instability and centrosome amplification. We provide evidence that both alterations are determined by the lack of paternal centriole, normally contributed by the sperm at the time of fertilization, but parthenogenetic cell lines activate a series of adaptive mechanisms that allow them to proliferate and differentiate. These include down-regulation of the p53/p21 pathway, massive increase of autophagic activity and formation of a wide network of intercellular bridges with the morphological and molecular characters of blocked cell abscissions. These processes are commonly observed in transformed cells therefore parthenogenesis may be used to explore the mechanisms regulating oncogenesis and their link with self-renewal and pluripotency in human cell lines.
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Robinson, Matthew R. "Selection and genetic variation of weaponry in a large mammal." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3479.
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Understanding the maintenance of the variation that is typically observed in natural populations has been a central aim of evolutionary biology. In a feral population of Soay sheep on the island of Hirta, St. Kilda there is a phenotypic polymorphism for horns with males growing either normal or reduced (scurred) horns, and females growing either normal, scurred or no (polled) horns, with further variation in horn size within each of the horn types. This thesis examines the potential factors which maintain these polymorphisms. I first present an overview of the literature relating to the factors that potentially maintain variance in traits in natural populations. In chapter two I present an analysis that suggests that polymorphisms in both horn type and horn size may be maintained by trade-offs between allocation to reproductive success and survival in males, and by sexually antagonistic selection between males and females. In chapter three I test the hypothesis that female weaponry may convey an advantage in intrasexual conflicts over resources, rather than just being expressed as a consequence of genetic associations with the male phenotype. Chapter four examines the environmental factors which create variation between individuals in their horn length, revealing that individuals vary in response to the environment. In chapter five I investigate whether the temporally fluctuating environmental conditions of St. Kilda generate fluctuating selection on the horn length of normal-horned males, revealing that this mechanism constrains the evolution of horn length potentially maintaining variance. In chapter six I examine the genetic relationships between morphological traits, revealing that these relationships are dependent upon the environmental conditions experienced during the first year of life. Finally, I discuss the wider implications of these findings for our understanding of the maintenance of trait variation in the wild.
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Jaaman, Saifullah A. "Marine mammal distribution and interactions with fisheries in East Malaysia." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430421.
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This study aimed to provide scientific information on the status of marine mammals and threats from directed takes and incidental catches in fisheries in East Malaysia. Recommendations for the conservation of the animals and guidelines for further research are also provided. All available information on sightings, strandings, skeletal remains and threats to the marine mammals in East Malaysia prior to this study were reviewed. A series of broad and aerial sighting surveys was conducted in the marine and fluvial waters. The objective was to explore and observe marine mammals at sea, and to describe the present species composition, distribution and density. In conclusion, this study showed that marine mammals in East Malaysian waters are diverse. Dugongs and small citations are facing threats from by-catches in fisheries, declining fisheries resources, habitat loss and degradation, pollution, heavy vessel traffic and rapid urban and industrial development along its coastline. In Sabah, traditional hunting for meat, illegal trawling in estuarine and riverine waters, and dynamite fishing are particularly detrimental to the species and their habitats. Without an immediate, committed and concerted effort to educate the public, monitor fisheries, enforce conservation laws and conduct detailed assessment of the dugong and small cetacean populations and their habitats, there may be little hope to reduce or eliminate the threats and to maintain their present numbers in the waters of East Malaysia.
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Plavsic, Militsa Justine. "Small mammal responses to fire in the Okavango Delta, Botswana." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612817.
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Clark, Sarah, and Joshua X. Dr Samuels. "Mammal Community Structure Analysis of the Gray Fossil Site, TN." Digital Commons @ East Tennessee State University, 2021. https://dc.etsu.edu/asrf/2021/presentations/63.
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The early Pliocene age Gray Fossil Site (GFS) was relatively recently found, with much still to be discovered and examined, and represents one of only a few sites of its age in eastern North America. It has been noted that the diverse faunal remains found at GFS are unique compared to what have been found at other fossil sites in North America from the same time period. Studying mammalian community structures at fossil sites can provide an abundance of information about the past environment and species adaptations to it, such as niche occupation of species, resource partitioning, and interactions between organisms and their environment. The main questions being asked in this study are: 1) what is the mammal community structure like at GFS?, and 2) how does the community structure at GFS compare to other contemporaneous sites? While studies of the fauna and flora have helped us to understand the ecosystem at GFS, detailed study of the mammal community will help us better understand this unique site. It is expected that the community structure and niche occupation of the mammals at GFS will be different from other contemporaneous sites, dominated by mammals adapted for life in the warm oak, hickory forest present at the site. A taxon-free approach to analysis will be used so that environments not sharing the same taxa or of different ages can be compared to one another. Each mammal species from GFS (48 total) and five well-known contemporaneous sites are categorized by body size, locomotor mode, and dietary preference to characterize the niches occupied by each species. Categorizations for each species will come from published works and measurements / ecomorphological analysis of specimens. Preliminary results show that GFS is different from other sites in that there are more brachyodont and tree dwelling/climbing adapted species present, and there are fewer running species present. The initial findings are likely associated with the site being a closed, forested ecosystem, compared to the more open environments of the other sites. Moving forward, descriptions pertaining to specifically how GFS and its mammal community structure compare to the niche occupation of similar species at other sites will be discussed. This project will also examine what more this analysis can reveal about the ecosystem at GFS, particularly how the herbivorous mammals can provide greater insight into what environmental conditions were like, including what vegetation was predominant at GFS.
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Keith, Anna. "Molecular Responses to Catastrophic Molting in a Wild Marine Mammal." Scholarly Commons, 2021. https://scholarlycommons.pacific.edu/uop_etds/3745.
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While most mammals shed their hair and skin either continuously or seasonally, northern elephant seals (Mirounga angustirostris) undergo an annual catastrophic molt, in which they shed their entire fur and underlying skin layer in the span of just three weeks. Due to the energetic and thermoregulatory constraints of molting and the large distances between their coastal rookeries and foraging grounds, elephant seals must remain on land and fast for the duration of their molt. Previous studies of molting northern elephant seals have examined endocrine and metabolic adjustments to fasting, but not the molecular processes underlying molting. We examined changes in the skin and underlying blubber tissues using histological, endocrine, and proteomic analyses during molting to provide a more in-depth understanding of the cellular mechanisms enabling rapid skin shedding and regeneration in this marine mammal. Shotgun proteome sequencing by LC-MS/MS identified 47,671 peptides and 573 protein groups in skin and outer blubber that were associated with lipid metabolism, protein processing in the endoplasmic reticulum, and collagen regulation. Label-free quantification and differential protein expression analyses identified 23 and 21 proteins that were differentially expressed during molting in the skin and outer blubber, respectively. Proteins downregulated over molting included those associated with inflammation, angiogenesis, and cellular proliferation, whereas proteins upregulated over molting included those associated with cytoskeletal remodeling, collagen synthesis, and lipid metabolism. This suggests that rapid skin regeneration involves intensive protein synthesis and increased vascularization that may be supported by fatty acid substrates from underlying blubber tissue. These data provide insights into cellular and molecular mechanisms that govern unusually rapid skin regeneration in mammals, which may further understanding of disorders affecting the skin and hair of humans and other mammals.
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Marques, Sara Isabel Ferreira. "Mammal choices in heterogeneous landscape of the Baixo Vouga Lagunar." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/13762.
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Mestrado em Biologia Aplicada - Ecologia, Biodiversidade e Gestão de EcossistemasThe relation between landscape structure and species distribution is a major question in landscape ecology. Terrestrial mammals are particularly susceptible to the spatial features, such as habitat type and landscape complexity, as well as to resource availability (e.g. shelter and food supply). The main objective of this thesis was to describe and understand the patterns of terrestrial non-volant mammal species richness, distribution and abundance in the heterogeneous landscape of Baixo Vouga Lagunar, north-western Portugal. Thus, small mammals and carnivores were sampled using three different strategies: a capture programme focused on small mammals (Rodentia and Eulipotyphla), and sign surveys and camera trapping for carnivores. In general, wetland habitats, such as reed beds, rushes and marshlands, seemed to favour small mammal fauna, being reed bed the habitat with the highest values of diversity. Furthermore, carnivore richness appeared to be favoured by the length of freshwater lines, and consequently by the associated riparian vegetation. Contrary, exotic forest was negatively related to both small mammal fauna and carnivore richness, and presented the lowest small mammal diversity. Overall, carnivore richness was mainly driven by landscape features, rather than by human influence and prey availability, or a combination of them. Surprisingly, prey availability seemed not to influence carnivore richness, probably as a consequence of a spatiallly wide availability of small mammals through the landscape matrix. Although at a fine-scale of the landscape, heterogeneity did not seem to influence the abundance of small mammals, at a broad-scale, the landscape matrix seems to promote small mammal diversity, since species distribution fluctuated throughout the patchy landscape. Contrasting, carnivore richness was negatively influenced by landscape heterogeneity and fragmentation, since the landscape is mainly composed by open habitats. Overall, the main findings of this study support the importance of hedgerow habitats (e.g. riparian gallery) to carnivore assemblage by providing water, shelter and enhancing landscape connectivity, and of wetland habitats for small mammal community. Furthermore, the results obtained revealed the reduced biological value of monocultures, especially forests of exotic species. This study reinforces the importance of the Baixo Vouga Lagunar region to wildlife and provides crucial information to develop adequate management and conservation guidelines.
A relação entre a estrutura da paisagem e a distribuição das espécies é um dos temas centrais da ecologia da paisagem. Os mamíferos terrestres são particularmente suscetíveis às características físicas do ambiente, como o tipo de habitat e a complexidade da paisagem, assim como à disponibilidade de recursos (e.g. abrigo e alimento). O principal objetivo deste estudo centrou-se na descrição e compreensão dos padrões de distribuição, abundância e riqueza específica dos mamíferos terrestres na paisagem heterogénea do Baixo Vouga Lagunar. Para tal foi amostrada a comunidade de micromamíferos e carnívoros com recurso a três metodologias distintas: programa de captura de micromamíferos (Rodentia e Eulipotyphla), e prospeção de indícios de presença e armadilhagem fotográfica de carnívoros. No geral, os resultados mostraram que os habitats húmidos, como os caniçais, juncais e sapais, favorecem a fauna de micromamíferos, sendo o caniçal o habitat que registou valores mais elevados de diversidade. Para além disso, a riqueza específica de carnívoros evidenciou ser favorecida pelo comprimento das linhas de água doce, e consequentemente pela vegetação ripícola associada. Pelo contrário, a floresta exótica composta por eucaliptos apareceu negativamente correlacionada com ambos os grupos de mamíferos, apresentando os valores mais baixos de riqueza específica de micromamíferos. As características da paisagem mostraram ser o fator mais importante para a riqueza de carnívoros, quando comparadas com a disponibilidade de presas e influência humana, ou com a combinação destes. Surpreendentemente, a disponibilidade de presas não influenciou a riqueza de carnívoros, o que pode ser uma consequência da ampla disponibilidade espacial de micromamíferos pela matriz da paisagem. Embora a uma pequena escala a heterogeneidade da paisagem pareça não influenciar a abundância de micromamíferos, à escala da paisagem o mosaico de habitats parece promover a diversidade de micromamíferos. Esta conclusão assenta sobre a distribuição das diversas espécies que varia pelas manchas de diferentes habitats. Por outro lado, a riqueza específica de carnívoros foi negativamente influenciada pela heterogeneidade e fragmentação da paisagem, a qual é composta maioritariamente por habitats abertos. Os principais resultados deste estudo suportam a importância dos habitats lineares para a comunidade de carnívoros no Baixo Vouga Lagunar, nomeadamente a galeria ripícola, e dos habitats húmidos para a fauna de micromamíferos, que lhes fornecem alimento. Revelaram ainda o reduzido valor biológico das monoculturas, em particular florestas de espécies exóticas. Este estudo reforça assim importância do Baixo Vouga Lagunar para a vida selvagem, e fornece bases essenciais para o desenvolvimento de medidas adequadas de gestão e conservação para a região.
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Hodgetts, Timothy James. "Enacting connectivity : woodland mammal conservation practices in England & Wales." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:8ff9ab6f-0472-45d3-bd24-b76e2f9bbd74.
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In recent years ideas about connectivity have become increasingly influential in theories pertaining to wildlife conservation. These ideas range from concerns with spatial habitat linkages or species' movements, to the forms of connection existing between 'people' and 'nature'. This thesis is concerned with how these various forms of connectivity are enacted in wildlife conservation through varied spatial practices. Following Mol (2002), I suggest that these modes of connectivity are enacted not separately but as a multiple. Indeed, through tracing how connectivity is enacted in a series of conservation situations relating to woodland mammals in England and Wales (red squirrels, pine martens, and wild/feral boar), I suggest that these multiple spatial practices of connectivity shape the biopolitical possibilities for living with non-human life. Since the connectivity multiple is composed, following Latour (2010) I further argue that it can be recomposed. Thus, I make the normative suggestion that contemporary trends in conservation policy (towards larger-scale action, process-based objectives, and neoliberal modes of governance) might be rethought and differently articulated through a conceptual and practical approach I term revitalizing conservation. This thesis thus makes several important contributions to geographic literatures. Following a widespread (re)affirmation of nonhuman agency in social science (e.g. Latour, 2005; Callon et al, 2009; Braun & Whatmore, 2010), and particularly the agential capacities of animals (Wolch & Emel, 1998; Philo & Wilbert, 2000), it foregrounds the role of woodland mammals in enacting connectivity through developing the concept of animal mobilities. Furthermore, it engages with existing work tracing affirmative possibilities for conservation (bio)politics (Whatmore, 2002; Lulka, 2009; Hinchliffe et al, 2005; Hinchliffe, 2008; J.Lorimer, 2010, 2012, 2015), by illuminating the intersection of spatial practices of connectivity, and the potential these offer for alternative modes of 'living with' more-than-human lives.
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Cambron, Richard. "Study of a Small Mammal Population in Bowling Green, Kentucky." TopSCHOLAR®, 1986. https://digitalcommons.wku.edu/theses/2202.
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The small mammal population of a restricted study area was live-trapped on the University farm at Western Kentucky University from November 1984 through November 1985. A total of 1800 trap-nights yielded 81 different individuals representing five species. Members of the genera Peromyscus and Microtus were the dominant individuals representing over 90% of the total. Also caught were Mus musculus and Blarina brevicauda. The members of the two major genera were examined for population size and dynamics. In addition, a statistical analysis was carried out on the randomness of the location of the home ranges. This analysis gave evidence that the Peromyseus population was centered primarily in the ecotone between field and forest while Microtus was centered exclusively in the field habitat. In addition, the absence or near absence of Microtus for part of the year allowed the Peromyscus population to expand into the field for a short time. Finally, the year long study revealed a characteristic population cycle for each major species due to a combination of reproductive rates, feeding habits and decimation by predation.
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Trostel, Kendrick A. "Investigation of causes of the 10-year hare cycle." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26651.
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This thesis combined data from a trapping and radio-telemetry study of snowshoe hares at Kluane Lake, Yukon from January 1984 through August 1985 with data collected at the same site from 1977-83 (Boutin et al. 1986; Krebs et al. 1986) to examine possible causes for the 10-year cycle in density of snowshoe hares.
In Chapter 2 I used data on causes of mortality, from a radio-telemetry study of a cyclic snowshoe hare population during 1978-84, to consider the importance of predation in causing the hare cycle. I found that predation during winter was the largest source of mortality for snowshoe hares during 1978-84. There was a 1-year lag in the response of predation mortality to changing hare density. There was a 2-year lag in the response to changing density of mortality due to causes other than predation. I incorporated this information on causes of mortality into a simulation model, to see whether observed predation mortality can cause changes in density similar to those of a cyclic population. I fitted the predation mortality data to a function in which total predator response consists of a Type II functional response and a delayed density-dependent numerical response. Using a simulation model that predicted mortality rates with this function, I produced 8-11 year cycles within parameter values measured in this study.
In Chapter 3 I compared a non-cyclic snowshoe hare population on Jacquot Island in Kluane Lake, with a cyclic population on the mainland, 40 km to the SE. I use trapping data from both mainland and island sites, for a period that included population increase, peak, and decline (1977-85) to test hypotheses of conditions sufficient to cause a hare population cycle. I also presented results from a radio-telemetry study, conducted on both mainland and island during a population low on the mainland (1984-85).
The hypothesis that high rates of recruitment followed by low rates of recruitment, is sufficient to cause a cycle was not supported. Data presented was consistent with hypotheses that any one of the following conditions was sufficient to cause the hare cycle: 1. High rates of survival followed by low rates of survival, particularly of juveniles 2. Delayed density-dependent predation 3. Periodic food shortage.Science, Faculty of
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Lambert, Catherine Marie Sarah. "Dynamics and viability of a cougar population in the Pacific Northwest." Connect to this title online, 2003. http://www.dissertations.wsu.edu/Thesis/Fall2003/c%5Flambert%5F100903.pdf.
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Gude, Justin Albert. "Applying risk allocation theory in a large mammal predator-prey system." Thesis, Montana State University, 2004. http://etd.lib.montana.edu/etd/2004/gude/GudeJ04.pdf.
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Understanding the behaviorally-mediated indirect effects of predators in ecosystems requires knowledge of predator-prey behavioral interactions, and the risk allocation hypothesis can be used to make predictions about such interactions. In predator-ungulate-plant systems, empirical research quantifying how predators affect ungulate group sizes and distribution, in the context of other influential variables, is particularly needed. We determined non-predation variables that affect elk (Cervus elaphus) group sizes and distribution on a winter range in the Greater Yellowstone Ecosystem (GYE), using regression analyses of 1219 elk groups counted and mapped over 12 years prior to wolf (Canis lupus) recolonization. We next examined the relevance of these non-wolf-predation variables in the presence of wolves using logistic and linear regression on surveys of 513 1-km² areas conducted over 2 years. Using model selection techniques, we evaluated risk allocation and other a priori hypotheses of elk group size and distributional responses to wolf predation risk while accounting for influential nonwolf- predation variables. We found little evidence that wolves affect elk group sizes, which were strongly influenced by habitat type. Following predictions from the risk allocation hypothesis, wolves likely created a more dynamic elk distribution in areas that they frequently hunted, as elk tended to move during the period of safety following wolf encounters in those areas. We predict that this distributional response to wolf predation risk should decrease the spatial heterogeneity of elk impacts on grasslands in areas that wolves frequently hunt. We also predict that this response should decrease browsing pressure on heavily-browsed woody plant stands in certain areas, which is supported by recent research in the GYE. This research highlights the importance of predator-prey behavioral interactions in large mammal systems.
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Yue, Sam. "Effects of oil palm plantations on mammal communities in northeastern Borneo." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50032.
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Agricultural expansion is considered the single largest threat to biodiversity. In Southeast Asia, the expansion of oil palm plantations is one of the leading causes of deforestation and habitat fragmentation. Studies have consistently shown that oil palm plantations support considerably lower biodiversity than native forest, yet little research has assessed how characteristics of the plantations influence diversity, or how edge effects of oil palm might impact species living in adjacent forest. I investigated whether 1) mammal diversity was different in oil palm plantations versus forest, 2) mammal diversity varied with characteristics of the plantations, such as tree height and proximity to forest, and 3) oil palm generated “edge effects” that reduced mammal diversity within nearby forest. Results were inconclusive as to whether the gamma diversity significantly differed between forest and oil palm at the α = 0.05 level. However, diversity and occurrence declined abruptly with decreasing forest proximity, suggesting that mammals within oil palm are largely constrained to locations in close proximity to native forest. Canopy cover and tree height within plantations had minimal relationships with mammal diversity and occurrence. I suggest that the only effective way to connect mammal populations in forests fragmented by oil palm development would be to retain or create large strips of forest through plantations to act as corridors. My results also suggest that degraded forests not yet converted to agriculture still retain relatively high conservation value and should not be replaced by oil palm.Science, Faculty of
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Dobson, Geoffrey P. "Metabolic regulation in skeletal muscle during exercise : a fish-mammal comparison." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27068.
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The aim of the present investigation was to examine the control of anaerobic glycogenolysis in working and fatigued skeletal muscle. The two animals chosen for the study were a teleost fish and the laboratory rat. The rationale behind using a comparative approach to investigate fundamental questions on metabolic control resides in the different abilities of each animal to perform exercise, and to their markedly different myofibrillar organization.
In the process of defining the hierarchical recruitment of fuel and pathway selection in rainbow trout fast-twitch white skeletal muscle, it was clear that the near-maximal myosin ATPase activity was supported solely by PCr hydrolysis. It was not until the rate and force of contraction decreased that the relative contribution of anaerobic glycogenolysis became increasingly important. Despite glycogenolysis possessing a lower maximal ATP generating potential than PCr hydrolysis, it has the advantage of being less constrained by time, and is recruited to extend muscle performance, but at submaximal workloads. Demonstration of the same temporal pattern of activation was not attempted for rat skeletal muscle because of complex fiber heterogeneity.
The etiology of fatigue after 10 and 30 minutes of burst swimming in trout was due to the near depletion of glycogen in white muscle. Inhibition of anaerobic glycogenolysis was not correlated with limitations to either the availability of ADP or NAD⁺ or inhibition ofphosphofructokinase (PFK-1). Similarly, the onset of fatigue and inhibition of glycogenolysis in three different skeletal muscles (gastrocnemius, plantaris and soleus) of the rat after 30 min of endurance treadmill running (25 meters/min), was not related to ADP availability, but associated with the near-depletion of muscle glycogen. As the endogenous stores of glycogen became limiting, hexokinase (Hk) appeared to be activated in trout white muscle after 10 min, and in the three rat skeletal muscles after 30 min, Indicating an increase in uptake and phosphorylation of blood-borne glucose.
In rats running at a high speed for 2 minutes, glycogenosis was maintained through the coordination of glycogen phosphorylase and PFK-1. Muscle performance in these rats was maintained despite large percentage swings in cytosolic redox, the ATP/ADP ratio and phosphorylation potential. A common belief in the literature is that inhibition of glycogenolysis during short-term strenuous exercise is brought about by the pH dependent ATP inhibition of PFK-catalysis. Evidence was provided indicating PFK-1 is operational in skeletal muscle at about pH 6.6 for both the fish and the rat. Fish partially solved the problem of PFK-1 inhibition by lowering ATP, whereas the rat appeared to rely on the synergistic action of a number of positive modulators. A detailed kinetic analysis of purified rabbit muscle PFK-1 revealed that any modulator that increases the ratio of unprotonated to protonated form of the enzyme, could supply the muscle cell with a means of maintaining glycogenolytic flux despite falling pH. A number of striking differences were apparent between the regulation of glycogenolysis in fish and rat skeletal muscle. The first major difference was the direction of change in cytosolic redox or the NAD+/NADH ratio. In fish white muscle the ratio increased, and the cytosol became more oxidized with exercise, whereas the opposite occurred in rat fast-twitch skeletal muscle. The difference was a consequence of lactate retention in fish white muscle. On the basis of crossover analysis, pyruvate kinase (PK) appeared to be activated in trout white muscle at both fatigue states. However, this was misleading, and also considered a consequence of rising pyruvate and due to lactate retention via the mass action effect at the LDH equilibrium. Obviously, the change in redox and the apparent crossover at PK are linked, and a literature survey revealed that during short-term maximal work, a mammalian skeletal muscle may indeed behave as fish white muscle. The other contrasting feature of this comparative analysis was the demonstration that ATP in trout white muscle can fall by 80% at exhaustion. No such large percentage reductions in ATP occurred in either of the rat fast-twitch skeletal muscles, or indeed have been reported in skeletal muscle of any other exercising animal. In all cases the total nucleotide pool remained constant.
A general conclusion to be drawn from this study is that muscle fatigue should be viewed as a multi-component process in response to limiting glycogen, and not leveled at any one particular step of the glycogenolytic pathway.Science, Faculty of
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Bowman, Jeffrey C. "The spatial structure of small-mammal populations in a managed forest." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0029/NQ62168.pdf.
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Watson, Rebecca Louise. "The causes and consequences of immune variation in a wild mammal." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25489.
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The immune system provides protection against parasites and is crucial for survival, but mounting, maintaining and controlling an immune response is expensive. Under limited resources these costs can lead to investment trade-offs between life history traits in order to maximize an individual's fitness. Understanding how these trade-offs relate to immunity can be important in understanding individual variation in fitness and the broader ecological implications that this may have in a population. In the wild there is evidence of trade-offs between life history traits and immunity, but there are relatively few studies which have measured specific aspects of the immune system under natural parasitic exposure. Using reagents developed in domestic sheep, I measured an unusually broad range of immune markers in a wild population of Soay sheep on the island of Hirta, St Kilda, Scotland. These include: T cell subsets (CD4+, CD8+, CD4+ & CD8+ naïve, gamma delta and Foxp3), anti-T.circumcincta (T. circ) antibody isotopes, (IgA, IgE, IgG), leukocyte subtypes (neutrophil:lymphocyte ratio & eosinophils), and leukocyte telomere length (LTL). I found that, in a year under high selection pressure for survival, anti-T. circ IgG positively predicted survival across all ages and for both sexes. Additionally, females had higher proportions of naïve T cells than males; a previously unreported sex difference in a wild mammal. In chapter 2, analysis of lambs in early life found higher growth rates associated with low antibody measures, while lower growth rates related to low antibody measures and high levels of inflammatory marker. I also found that male lambs with high anti-T. circ IgE and IgG were less likely to survive over-winter, contrary to the findings across all ages in chapter 1. In chapter 3, I detected an increase in LTL attrition with age in males >3 years, but this was not significant in females or in younger animals. In male lambs, high investment in horn growth was related to reduced LTL. Changes in LTL were independent of variation in leukocyte cell populations. The data in this thesis demonstrate the complexity of immune variation in the wild, and highlight the value of multiple ecologically relevant markers to understanding the evolutionary implications of resource trade-offs.