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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Inventering av lodjur (Lynx lynx), och vilka faktorer som kan påverka lodjursbesök vid kamerastationer / Monitoring Eurasian lynx (Lynx lynx), and different factors that impact lynx visits at camera stations

Classon, Ida January 2017 (has links)
Att använda sig av viltkameror är ett bra verktyg vid inventering av djur, speciellt för skygga arter som till exempel lodjur. I Sverige baseras lodjursinventering genom spårning i snö, men då varmare vintrar har gjort det svårt kan inventering genom viltkameror ersätta denna metod. I denna studie har 165 kamerapositioner från mellersta Sverige undersökts. Syftet med studien var att se om någon av faktorerna; väg, avverkad skog, blockmark, byggnader, tidigare spårningar, doftstation samt kadaver hade något samband med att fånga lodjursbesök på foto/film, då detta kan ge bättre och effektivare metoder vid lodjursinventering. Koordinaterna över de olika kamerapositionerna har lagts in i ett GIS-program. Utifrån olika buffertzoner runt varje kameraposition, 50 - 500 meter i radie har de olika faktorerna kunnat urskiljas, det vill säga om faktorn fanns eller inte fanns inom kameraområdet. Doftstation samt kadaver var redan en fast faktor för vissa kamerapositioner. Studien visar att det finns ett samband mellan lodjursbesök och doftstation (Chi2 6,606; P<0,05), med större sannolikhet att få ett lodjursbesök vid en kameraplats med doftstation än utan (figur 5). Resultatet visar vikten i att använda sig av lockmedel då syftet är att fånga lodjur på foto eller film, då detta ökar chansen att lodjuret går framför kameran och bilden tas. Resterande faktorer verkar inte ha en påverkan i att få lodjursbesök på bild.
22

Relatedness Assessment and Analysis of Road Mortality Effects on <i>Lynx rufus</i> in Ohio

Heffern, William J. 10 September 2021 (has links)
No description available.
23

Påverkan av jakt och katastrofer på lodjursstammen (Lynx lynx) i Sverige: En sårbarhetsanalys / The effets of hunting and catastrophes on the lynx (Lynx lynx) in Sweden: A population viability analysis

Dahlberg, Julia January 2024 (has links)
The eurasian lynx (Lynx lynx) has a wide distribution and occurs in the palearctic region. In Europe, the lynx has been persecuted and exterminated from several of its natural distribution areas and has also been subject to persecution in Sweden, where a high hunting pressure led to a reduced population that almost went extinct. Today, the Swedish lynx population has recovered but is kept down by licensed hunting, which is strictly controlled due to the lynx's protection status. However, Sweden's government has backed a proposal for reduced protection that could potentially lead to higher hunting quotas and thus threaten the lynx's future, because of predators’ vulnerability to high hunting pressures and smaller populations’ vulnerability to stochastic events such as catastrophes. The purpose of this study was to investigate the development of the Swedish lynx population and how high the risk of extinction is now, with increased hunting quotas and if catastrophes would occur both with current hunting quotas and increased hunting quotas. Based on the purpose, the questions that were answered were the following: 1) What does the population development and extinction risk look like for the Swedish lynx population in the next 100 years with current hunting quotas? 2) How do higher hunting quotas affect the Swedish lynx population development and extinction risk in the next 100 years? 3) How would catastrophes with current hunting quotas and increased hunting quotas affect the Swedish lynx population development and extinction risk in the next 100 years? The questions were answered through a population viability analysis performed in Vortex 10 where four scenarios were created. In scenario 1, the null scenario, the Swedish lynx population development and extinction risk over 100 years were investigated in relation to current hunting quotas. In scenario 2, the Swedish lynx population development and extinction risk over 100 years were investigated in relation to current hunting quotas and catastrophes. In scenario 3, the Swedish lynx population development and extinction risk over 100 years were investigated in relation to increased hunting quotas. In scenario 4, the Swedish lynx population development and extinction risk over 100 years were investigated in relation to increased hunting quotas and catastrophes. The scenarios with the largest and smallest average population size after 100 years were scenario 1 and scenario 4, respectively. The growth rate was highest and lowest for scenario 1 and scenario 4, respectively. Scenarios 2, 3 and 4 had a negative growth rate. The extinction risk for scenarios 1 and 2 was 0% and scenarios 3 and 4 had an extinction risk of 1%. To conclude, the results indicate that the current hunting quotas do not threaten the Swedish lynx population, but that catastrophes have a negative impact on population growth at current hunting quotas, and that the increased hunting quotas have a negative impact as they result in a reduced population and a negative growth rate both with and without catastrophes. / Det eurasiska lodjuret (Lynx lynx) har en vid utbredning och förekommer i den palearktiska regionen. Lodjuret har i Europa förföljts och utrotats från flera av dess naturliga utbredningsområden och även i Sverige har lodjuret varit utsatt för förföljelse där ett högt jakttryck ledde till en minskad population som nästan utrotades. Idag har den svenska lodjursstammen återhämtat sig men hålls nere genom licensjakt, som är strikt kontrollerad på grund av lodjurets skyddsstatus. Däremot har Sveriges regering ställt sig bakom ett förslag till minskat skydd som potentiellt kan leda till högre jaktkvoter och därmed hota lodjurets framtid eftersom rovdjur är sårbara för höga jakttryck, samt att mindre populationer är mer sårbara för slumpmässiga händelser såsom katastrofer. Syftet med arbetet var att undersöka den svenska lodjursstammens utveckling och utdöenderisk i nuläget, vid förhöjda jaktkvoter, samt om katastrofer skulle inträffa vid nuvarande jaktkvoter respektive förhöjda jaktkvoter. Utifrån syftet besvarades följande frågeställningar: 1) Hur ser populationsutvecklingen och utdöenderisken ut för den svenska lodjursstammen under kommande 100 år med nuvarande jaktkvoter? 2) Hur påverkar högre jaktkvoter den svenska lodjursstammens populationsutveckling och utdöenderisk under kommande 100 år? 3) Hur skulle katastrofer vid nuvarande jaktkvoter respektive förhöjda jaktkvoter påverka den svenska lodjursstammens populationsutveckling och utdöenderisk under kommande 100 år? Frågeställningarna besvarades genom en sårbarhetsanalys som utfördes i Vortex 10 där fyra scenarier skapades. I scenario 1, grundscenariot, undersöktes den svenska lodjursstammens populationsutveckling och utdöenderisk över 100 år i förhållande till nuvarande jaktkvoter. I scenario 2 undersöktes den svenska lodjursstammens populationsutveckling och utdöenderisk över 100 år i förhållande till nuvarande jaktkvoter och katastrofer. I scenario 3 undersöktes den svenska lodjursstammens populationsutveckling och utdöenderisk över 100 år i förhållande till förhöjda jaktkvoter. I scenario 4 undersöktes den svenska lodjursstammens populationsutveckling och utdöenderisk över 100 år i förhållande till förhöjda jaktkvoter och katastrofer. Största respektive minsta genomsnittlig populationsstorlek efter 100 år fick scenario 1 respektive scenario 4. Tillväxthastigheten var högst respektive lägst för scenario 1 respektive scenario 4. Scenario 2, 3 och 4 hade alla en negativ tillväxthastighet. Utdöenderisken för scenario 1 och 2 blev 0% och scenario 3 och 4 hade en utdöenderisk på 1%. Resultaten tyder på att de nuvarande jaktkvoterna inte hotar den svenska lodjursstammen men att katastrofer ger en negativ påverkan på populationstillväxten vid nuvarande jaktkvoter, samt att de förhöjda jaktkvoterna har en negativ påverkan då de ger en minskad population och en negativ tillväxthastighet både med och utan katastrofer.
24

Impact de la prédation des grands carnivores (loup Canis lupus et lynx Lynx lynx) sur les populations d'ongulés sauvages (espèces Nord-Paléarctique)

Perret, Emmanuelle January 2003 (has links) (PDF)
Rapport de recherche bibliographique Diplôme d'études supérieures spécialisées : Ingénierie documentaire : Villeurbanne, ENSSIB : 2003. Rapport de recherche bibliographique Diplôme d'études supérieures spécialisées : Ingénierie documentaire : Lyon 1 : 2003.
25

ASSESSMENT AND SPATIAL ANALYSIS OF BOBCAT PARASITES IN SOUTHERN ILLINOIS

Hiestand, Shelby Jane 01 August 2013 (has links)
Bobcats (Lynx rufus) are the most abundant and widely-distributed wild felid species in North America. The current increase of population densities of bobcats raises concerns about their importance as reservoirs of pathogens and parasites that may affect the wildlife community. Although many parasites found in bobcats also infect other wild and domestic animals, knowledge of bobcat parasites and potential impacts on other species has received relatively little attention. My objectives were to determine the endoparasite species present in Illinois bobcats, compare them to previous records in the United States, and predict their potential presence in southern Illinois using the program MAXENT. To complete these goals, necropsies were performed on 67 road-killed or trapped bobcats collected during 2003-12. I found infections caused by cestodes, nematodes, and trematodes including Taenia rileyi (70.1%), Toxocara cati (25.3%), and Alaria marcianae (41.7%). The highest mean abundance was found for Alaria marcianae (81) followed by Taenia rileyi (4) and Toxocara cati (3). Alaria marcianae had the highest intensity (193) with a range of 1-2,872. The comparison of parasite communities across 10 geographic locations using Jaccard's similarity index showed low similarity among all regions with the most similar community between Nebraska and Texas (0.53) and Arkansas being the most similar to southern Illinois (0.74). Parasite presence data were then used with environmental data layers of water, soil, land cover, human density, and climate variables in MAXENT to create maps of potential presence of 3 parasite species in a 46,436-km2 portion of southern Illinois. Precipitation of seasonality, the change of average rainfall seasonally, and average precipitation were the highest contributing variables used by MAXENT when creating probability maps of Taenia rileyi (55.1%) and Alaria marcianae (58.4%). For Toxocara cati land cover (40.6%) and soil (27.6%) were the highest contributing variables. With the addition of a sampling bias layer (i.e., bobcat presence) all climatic variables were low contributors (0.0-2.0%) while land cover remained important for Alaria marcianae (7.6%) and Toxocara cati (6.3%); human density (4.8%) was of secondary importance for Taenia rileyi after including the bias layer. Variables of importance likely represent habitat requirements necessary for the completion of parasite life cycles. Larger areas of potential presence were found for generalist parasites such as Taenia rileyi (85%) while potential presence was less likely for parasites with complex life cycles such as Alaria marcianae (73%). My study provides information to wildlife biologists and health officials regarding the potential impacts of growing bobcat populations in combination with complex and changing environmental factors.
26

Lynx Mission concept status

Gaskin, Jessica A., Allured, Ryan, Baysinger, Michael F., Capizzo, Peter D., Civitani, Marta M., DeRoo, Casey T., DiPirro, Michael J., Figueroa-Feliciano, Enectali, Garcia, Jay C., Heilmann, Ralf K., Hopkins, Randall C., Jackson, Thomas, Kilaru, Kiranmayee, Liu, Tianning, McClelland, Ryan S., McEntaffer, Randy L., McCarley, Kevin S., Mulqueen, John A., Reid, Paul B., Saha, Timo T., Schattenburg, Mark L., Schwartz, Daniel A., Solly, Peter M., Suggs, Robert M., Sutherlin, Steven G., Trolier-McKinstry, Susan, Tutt, James H., Bandler, Simon R., Basso, Stefano, Bautz, Marshall W., Biskach, Michael P., Boswell, Tyrone M., Chan, Kai-Wing, Cohen, Lester M., Cotroneo, Vincenzo, Davis, Jacqueline M., Dominguez, Alexandra, Fabisinski, Leo L., Falcone, Abraham D., Gelmis, Karen E., Kraft, Ralph P., Özel, Feryal, Pareschi, Giovanni, Riveros, Raul E., Rodriguez, Mitchell A., Rowe, Justin W., Schnell, Andrew R., Swartz, Douglas A., Vikhlinin, Alexey, Walker, Julian, Yoon, Wonsik, Zhang, William W. 19 September 2017 (has links)
Lynx is a concept under study for prioritization in the 2020 Astrophysics Decadal Survey. Providing orders of magnitude increase in sensitivity over Chandra, Lynx will examine the first black holes and their galaxies, map the large-scale structure and galactic halos, and shed new light on the environments of young stars and their planetary systems. In order to meet the Lynx science goals, the telescope consists of a high-angular resolution optical assembly complemented by an instrument suite that may include a High Definition X-ray Imager, X-ray Microcalorimeter and an X-ray Grating Spectrometer. The telescope is integrated onto the spacecraft to form a comprehensive observatory concept. Progress on the formulation of the Lynx telescope and observatory configuration is reported in this paper.
27

Lynxrufus wilsoni n.g., n.sp. (Nematoda: metastrongylidae) from the lungs of the bobcat, Lynx rufus rufus (Shreber)

Stough, Betty Delores 28 July 2008 (has links)
Of sixty-four bobcats, Lynx rufus rufus, collected in Virginia end North Carolina, twenty-five percent were found to be infected with an unidentified lungworm. As the literature showed no record of lungworm parasites from Lynx rufus rufus, a study was made of the lungworms of the cat family, Felidae. A new metastrongylid genus and species is here described, named and classified. The name is designated as Lynxrufus wilsoni. Lynxrufus wilsoni is placed tentatively in the subfamily Skrjabingylinae due to the similarity of its male reproductive organs to the male reproductive organs of the other members of that subfamily. / Ph. D.
28

An Inventory Of Medium And Large Mammal Fauna In Pine Forests Of Beypazari Through Camera Trapping

Mengulluoglu, Deniz 01 October 2010 (has links) (PDF)
Information about large mammals in Turkey usually does not go further than species lists or annual counts of particular species such as the wild goat. Camera trapping is a very useful technique to overcome this deficiency by gathering information about species presence, numbers, habitat use and behavior. Hence, a one year long camera trap study was conducted to demonstrate the diversity, activity, distribution patterns, habitat preferences and interspecific interactions of medium and large mammals in a 148 km2 large pine woodland near Ankara. Brown bear (Ursus arctos), wolf (Canis lupus), Eurasian lynx (Lynx lynx), golden jackal (Canis aureus), jungle cat (Felis chaus), red fox (Vulpes vulpes), Eurasian badger (Meles meles), stone marten (Martes foina), red deer (Cervus elaphus), wild boar (Sus scrofa), brown hare (Lepus europaeus), Caucasian squirrel (Sciurus anomalus) and southern white-breasted hedgehog (Erinaceus concolor) were the 13 mammal species captured during the study. Spatial segregation was observed among canid species indicating intraguild competition and competitive exclusion. Prey-predator interactions were documented at both spatial and temporal scales between wolves, deer and wild boars. Red deer showed seasonal and sex differences in activity patterns that appeared to be influenced by wolf predation risk. The presence of two felids unknown to the local people were revealed by camera trapping, showing the utility of this technique for such secretive and rare species. However, the low encounter rates for particular species such as lynx, brown bear and jungle cat indicated the importance of the length of study. Based on various evidence, resident adult population sizes were estimated for wolf (2-5), Eurasian lynx (2-4), brown bear (0-2) and jungle cat (2-3). The study showed that lynx can exist in high densities in a relatively small area when prey species are abundant. This study area hosted a rich mammal fauna in spite of human activities such as livestock grazing, logging and hunting. A relatively intact ecosystem, high altitudinal and habitat diversity, and a positive attitude of local people are believed to be the reasons of this observed high diversity.
29

Ekologie rysa ostrovida (Lynx lynx) a vlka obecného (Canis lupus) v oblasti Západních Karpat a jejich význam v lesním ekosystému

Kutal, Miroslav January 2014 (has links)
The abundance and population density of the Eurasian lynx (Lynx lynx) were studied during two winters 2011/2012 and 2012/2013 in the in Beskydy and Kysuce protected landscape areas in the West Carpathians in the Czech-Slovak borderline. A combination of camera trapping, photographic capture-mark-recapture (CMR) and simultaneously conducted snow tracking revealed 11 independent lynx in both seasons in the total area of 1500 km2 and overall population density of 0.7 lynx/100 km2. High population turnover of 54.5% was documented between the two winters, indicating a strong anthropogenic pressure at the edge of the West Carpathian population. The main prey of Eurasian lynx in winter was a roe deer (81%) and red deer (16%). The occurrence of wolves (Canis lupus) was considered to be sporadic and probably limited to only a few individuals. The nearest reproductive packs were documented at a distance of 10--50 km from the Czech border in the Slovak Carpathians.
30

Corpus luteum of the domestic cat and lynx

Amelkina, Olga 10 March 2016 (has links)
Der Gelbkörper (corpus luteum, CL) ist eine transitorische Drüse, die im Ovar nach der Ovulation gebildet wird und durch ihre Progesteron-(P4)-Produktion die Trächtigkeit unterstützt. Bei allen bisher untersuchten Säugetieren endet die sekretorische Aktivität der CL mit dem Ende der Trächtigkeit oder Laktation, danach werden die CL abgebaut. Der Zyklus von Katzenartigen, wie etwa der Hauskatze, folgt dem gleichen Muster. Anders verläuft der Zyklus bei Luchsen. Beim Eurasischen Luchs (Lynx lynx) und beim Pardelluchs (Lynx pardinus) persistieren die CL nach der Geburt für mehr als zwei Jahre und sezernieren weiter P4. Die vorgestellte Arbeit sollte die Funktion persistierender (per) CL im Luchs untersuchen und die Fortpflanzung von Katzen weiter aufklären. Dazu wurden grundlegende histologische und hormonelle Aspekte der Lutealphase analysiert und der Einfluss des apoptotischen Systems sowie die Rezeptivität gegenüber Steroiden bei der Regulation der CL-Funktion betrachtet. Die CL von Hauskatzen und Luchsen wurden histomorphologisch unterteilt. In allen Proben wurden intraluteales P4 und Östrogene bestimmt. Weiterhin wurde die mRNA- und, wenn möglich, die Proteinexpression der proapoptotischen Faktoren BAX, Caspase-3, FAS, Tumor necrosis factor (TNF), TNF Rezeptor 1 (TNFRSFA1) und der Überlebensfaktoren (BCL2, TNFRSFB1), sowie des Progesteronrezeptors (PGR), der PGR-Membrankomponente (PGRMC) 1 und 2, des Östrogenrezeptors (ESR) 1 und 2, des G-Protein-gekoppelten Östrogenrezeptors 1 (GPER1) und des Androgenrezeptors (AR) gemessen. Die Ergebnisse weisen darauf hin, dass die Lutealphase der Hauskatze durch FAS, Caspase-3 und die TNF Rezeptoren 1 und 2 reguliert sein könnte. Steroide könnten über ihre Rezeptoren PGR, PGRMC1 und PGRMC2, ESR1 und AR wirken. Die physiologische Persistenz der CL beim Luchs könnte über BCL2, FAS, TNFRSFB1, PGRMC1, PGRMC2, ESR1, GPER1 und AR vermittelt werden. / Corpus luteum (CL) is a transitory gland which forms in the ovary after ovulation and supports the pregnancy with its production of progesterone (P4). In all mammals studied so far, the CL loses its secretory activity after pregnancy and regresses from the ovary. The feline luteal cycle follows the same pattern, and CL of the domestic cat functionally and structurally regress after lactation. However, the story is different for the lynx. In the Eurasian (Lynx lynx) and Iberian (Lynx pardinus) lynx, CL persist after parturition, weaning and for up to two years, still retaining their ability to secrete P4. Current work was initiated to understand the control of unusual persistent (per) CL in lynx and to learn more about feline reproduction in general. For this, studies on the basic histological and endocrinological aspects of the feline luteal phase, as well as potential involvement of systems of apoptosis and steroid receptivity in the CL regulation were performed. Collected CL from domestic cats and lynx were classified based on their histomorphology. In all samples, intraluteal P4 and estrogens were measured. Moreover, mRNA and where possible protein levels were determined for pro-apoptotic BAX, caspase-3, FAS, tumor necrosis factor (TNF), TNF receptor 1 (TNFRSFA1), pro-survival BCL2, TNFRSFB1, and for progesterone receptor (PGR), PGR membrane components (PGRMC) 1 and 2, estrogen receptors (ESR) 1 and 2, G protein-coupled estrogen receptor 1 (GPER1) and androgen receptor (AR). The results suggest that the luteal phase of the domestic cat is potentially regulated by caspase-3, FAS, TNFRSF1A, TNFRSF1B, and by actions of steroids via PGR, PGRMC1, PGRMC2, ESR1 and AR. Physiological persistence of Iberian lynx CL might be mediated by BCL2, FAS, TNFRSFB1, PGRMC1, PGRMC2, ESR1, GPER1 and AR. Current work indicates profound differences between the CL function and regulation in domestic cats and lynx, and promotes a highly species-specific approach in reproduction studies.

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