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Population structuring and dispersal in the highly pelagic Leach's storm-petrel : implications for the EU populationBicknell, Anthony William James January 2011 (has links)
Dispersal is a fundamental process that shapes many aspects of population ecology and evolution. Dramatic local population declines brought about by anthropogenic-driven changes to ecological processes are unfortunately becoming ubiquitous and increasing the urgency to understand dispersal behaviour in many species. For species where direct methods of tracking movement and dispersal are unsuitable, other indirect methods need to be employed to understand and characterise these behaviours. The steep population decline, due to predation, at the largest EU population of Leach’s storm-petrels Oceanodroma leucorhoa (St Kilda, Scotland), and the potential part immigrant birds have in buffering this threat, highlighted the need to understand dispersal and connectivity of widely spaced colonies in this species. The implications for the persistence of local colonies and the wider population of Leach’s storm-petrels could then be assessed. A population genetic analysis of 9 colonies across the North Pacific and Atlantic distribution, using two DNA markers (mtDNA control region and microsatellites), revealed ocean basin differentiation (Global ST = 0.32 P <0.0001, Global FST = 0.04, P <0.0001) but also identified a migrant individual in the Pacific population (STRUCTURE migrant assignment). The Atlantic population was found to be genetically homogenous, with patterns of historical and contemporary gene flow, indicating that long-distance effective dispersal is prevalent in Leach’s storm-petrels within the ocean basin. Bayesian stable isotope analysis of carbon and nitrogen (13C & 15N) provides evidence for natal dispersal as an important dispersal mechanism, and reveals movement of immature birds between colonies during the breeding season as a likely mechanism to promote inter-colony exchange and gene flow. Stable isotope comparison also identified mixing on wintering grounds as another possible influence on dispersal. The potential for immigrant birds to offset the loss caused by predation at the St Kilda colony is supported by these studies, and will likely help the persistence of the colony in the short-term. However, future viability is debateable considering the evidence for both avian and mammalian predation. This research provides a better understanding of the extent and mechanism of dispersal in the Leach’s storm-petrel, which is important to predict the potential impact of environmental change and, where possible, implement effective population management for this species.
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Aspectos sobre a biologia de daption capense na Ilha Elefante, AntárticaBasler, Aparecida Brusamarello 23 July 2012 (has links)
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Previous issue date: 2012 / Nenhuma / Daption capense apresenta distribuição circumpolar, sendo bastante abundante no Hemisfério Sul. Reproduz principalmente em ilhas subantárticas, na Península e no Continente Antártico. Na Ilha Elefante, Arquipélago das Shetlands do Sul, também se apresenta como reprodutivo, porém poucos dados sobre a sua biologia são encontrados para esta localidade. É considerado um pequeno Procellariiforme, e dentro deste grupo, como a espécie que menos apresenta dimorfismo entre os indivíduos, porém podem apresentar certa diferença quanto às medidas morfométricas. Medidas morfométricas têm sido consideradas importantes ferramentas na suposição de determinado sexo. Considerando-se a importância das variáveis morfométricas na compreensão dos aspectos biológicos e em especial para a determinação sexual, objetivouse com este estudo (i) determinar o sexo dos indivíduos de D. capense através de técnicas moleculares e (ii) verificar quais variáveis morfométricas distinguem melhor machos de fêmeas. O estudo foi realizado na Ilha Elefante, nos períodos correspondentes ao verão austral, entre os anos de 2010/11 e 2011/12. Foram capturados 52 indivíduos adultos de D. capense, sendo 32 no verão austral de 2010/11 e 20 entre os anos de 2011/12, os quais foram anilhados e realizadas as medidas morfométricas. Foram coletadas ainda amostras de sangue para a realização de sexagem, dos quais 33 foram determinados como machos e 19 como fêmeas. As variáveis mais significativas para a determinação sexual, segundo a Análise Discriminante Stepwise foram dedo médio (F=12,222; gl 1,50; p=0,001) e a altura do bico (F=18,931; gl 2,49; / Daption capense presents circumpolar distribution, being very abundant in the Southern Hemisphere Plays mainly in subantarctic islands, the Antarctic Peninsula and on the Continent. In Elephant Island, South Shetland Archipelago is also presented as breeding, but few data on its biology are found for this location. It is considered a small Procellariiform, and within this group, as the species shows that less dimorphism among individuals, but may have some difference as to morphometric measurements. Given the importance of morphometric variables in the understanding of biological aspects, particularly for determining sexes, the objective of this study is to (i) determine the sex of individuals of D. capense through molecular techniques and (ii) verify which morphological variables better distinguish males from females. The study was conducted on Elephant Island, between October and March, which corresponds with austral summer in the Southern Hemisphere, in 2010/2011 and 2011/12. Fifty-two adult D. capense individuals were captured: 32 in the austral summer of 2010/11 and 20 in the years 2011/12. Each bird was banded and measured. Blood samples were collected to be used in determining the sex of the individuals, which showed that 33 were males and 19 were females. The average and standard error were calculated for the morphometric measurements of the individuals before and after sex determination. Sexual dimorphism between males and females of D. capense was confirmed, and the significant morphometric variables for sexual determination were middle toe length (F=12.222; gl 1, 50; p=0.001) and beak height (F=18.931; gl 2, 49; p
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3D modeling in Petrel of geological CO2 storage site / 3D modellering i Petrel av geologiskt CO2 lagringsområdeGunnarsson, Niklas January 2011 (has links)
If mitigation measures are not made to prevent global warming the consequences of a continued global climate change, caused by the use of fossil fuels, may be severe. Carbon Capture and Storage (CCS) has been suggested as a way of decreasing the global atmospheric emission of CO2. In the realms of MUSTANG, a four year (2009-2013) large-scale integrating European project funded by the EU FP7, the objective is to gain understanding of the performance as well as to develop improved methods and models for characterizing so- called saline aquifers for geological storage of CO2. In this context a number of sites of different geological settings and geographical locations in Europe are also analyzed and modeled in order to gain a wide understanding of CO2 storage relevant site characteristics. The south Scania site is included into the study as one example site with data coming from previous geothermal and other investigations. The objective of the Master's thesis work presented herein was to construct a 3D model for the south Scania site by using modeling/simulation software Petrel, evaluate well log data as well as carry out stochastic simulations by using different geostatistical algorithms and evaluate the benefits in this. The aim was to produce a 3D model to be used for CO2 injection simulation purposes in the continuing work of the MUSTANG project. The sequential Gaussian simulation algorithm was used in the porosity modeling process of the Arnager greensand aquifer with porosity data determined from neutron and gamma ray measurements. Five hundred realizations were averaged and an increasing porosity with depth was observed. Two different algorithms were used for the facies modeling of the alternative multilayered trap, the truncated Gaussian simulation algorithm and the sequential indicator simulation algorithm. It was seen that realistic geological models were given when the truncated Gaussian simulation algorithm was used with a low-nugget variogram and a relatively large range. / Den antropogena globala uppvärmningen orsakad av användandet av fossila bränslen kan få förödande konsekvenser om ingenting görs. Koldioxidavskiljning och lagring är en åtgärd som föreslagits för att minska de globala CO2-utsläppen. Inom ramarna för MUSTANG, ett fyra år långt (2009-2013) integrerande projekt finansierat av EU FP7 (www.co2mustang.eu), utvecklas metoder, modeller och förståelse angående så kallade saltvattenakviferers lämplighet för geologisk koldioxidlagring. En del av projektet är att analysera ett antal representativa formationer i olika delar av Europa för att få kunskap angående förekommande koldioxidlagringsspecifika egenskaper hos saltvattenakviferer. Ett av områdena som har inkluderats är i sydvästra Skåne. Syftet med detta examensarbete var att konstruera en 3D modell över detta område med hjälp av modellerings/simuleringsprogrammet Petrel, utvärdera borrhålsdata samt genomföra stokastiska simuleringar med olika geostatistiska algoritmer och utvärdera dem. Målsättningen var att konstruera en modell för CO2 injiceringssimuleringar i det forstsatta arbetet inom MUSTANG-projektet. En algoritm av sekventiell Gaussisk typ användes vid porositetsmodelleringen av Arnager Grönsandsakviferen med porositetsdata erhållen från neutron- och gammastrålningsmätningar. Ett genomsnitt av femhundra realisationer gjordes och en porositetstrend som visade en ökning med djupet kunde åskådligöras. Två olika algoritmer användes vid faciesmodelleringen av den alternativa flerlagrade fällan: en algoritm av trunkerade Gaussisk typ och en sekventiell indikatorsimuleringsalgoritm. Resultaten tyder på att en realistisk geologisk modell kan erhållas vid användandet av den trunkerande algoritmen med ett låg-nugget variogram samt en förhållandevis lång range.
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3D seismická interpretace a zpracování modelu schrattenbergského zlomového systému v oblasti Valtic / 3D seismic interpretation and model of the Schrattenberg fault system in the Valtice areaHlaváčková, Šárka January 2012 (has links)
3D SEISMIC INTERPRETATION AND MODEL OF THE SCHRATTENBERG FAULT SYSTEM IN THE VALTICE AREA Šárka Hlaváčková Abstract The Schrattenberg normal fault system represents a dominant feature of the western margin of the Vienna Basin. Along with the Steinberg fault, they controlled the sedimentary and tectonic development of the area, and considerably participated in the deposition of the basin fill during a relatively short period of time in the Miocene. A detailed interpretation of the fault system is essential for full understanding of the local basin development and its geological architecture. The oil exploration industry targets mainly the Steinberg and Schrattenberg fault system because of the occurrences of oil and natural gas deposits that are related to the basin tectonics, which forms structural traps sealed by the main fault systems or by minor synthetic or antithetic faults. The thesis presents a geological framework of the Mistelbach block near Valtice at the western margin of the Vienna Basin. Geological interpretation includes also the fault framework modeling with the emphasis on the course of the Schrattenberg fault system. The model was built in the Petrel interpretation software with the use of the principles of the 3D seismic interpretation. In particular, seismic stratigraphy methods, Petrel...
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The importance of fisheries waste in the diet of Westland Petrels (Procellaria westlandica)Freeman, A. N. D. January 1997 (has links)
Westland petrels Procellaria westlandica breed only near Punakaiki on the West Coast
of New Zealand. About 80 km offshore from their breeding colony, New Zealand's largest commercial fishery (for hoki Macruronus novaezelandiae) operates from mid June to early September, coinciding with the Westland petrel's breeding season.
It has been assumed that Westland petrels feed extensively on fisheries waste and that
this habit has been at least partly responsible for the increase in the Westland petrel
population. Some seabird biologists have expressed concern that if a species comes to
depend on scavenging at fishing vessels, such a species could experience a food crisis if
fishing operations changed in a way that reduced the quantity of waste discharged. The aim of this research was to assess how dependent Westland petrels have become on fisheries waste for food.
Diet studies showed that during the hoki fishing season, waste accounts for more than half by weight of the solid food Westland petrels bring back to the colony to feed their chicks. After the hoki season, waste contributes only about a quarter of their diet as birds switch to more natural prey and scavenge a wider variety of fish species presumably from smaller, inshore fishing vessels.
Much of the fisheries waste eaten by Westland petrels was flesh which could not be identified using traditional techniques. The electrophoretic technique iso-electric focusing increased the number of fish samples that could be identified and consequently the diet was interpreted differently than it would have been had only traditional diet analysis been used.
The survey of Westland petrel distribution off the west coast of the South Island, found
that although hoki fishing vessels influence the distribution of Westland petrels, only a small proportion of the Westland petrel population appears to utilise this food resource at any one time.
Westland petrels were tracked at sea by VHF radio telemetry and then by satellite tracking. Satellite tracking showed that there is considerable variation in the amount of
time Westland petrels spend in the vicinity of fishing vessels. On average, satellite tracked birds spent one third of their time near vessels, but they foraged over much larger areas than that occupied by the West Coast South Island hoki fishing fleet.
Although fisheries waste is an important component of the Westland petrel diet, it appears that the situation is one of opportunistic use of a readily available resource, rather than one of dependence. Several features of the Westland petrel's breeding biology and foraging ecology suggest that Westland petrels could compensate for a reduction in waste from the hoki fishery by switching to other sources of waste and
increasing their consumption of natural prey.
Nevertheless, much remains unanswered concerning the role of fisheries waste in the Westland petrel's diet. In particular, quantifying the waste available to seabirds, and the
success of Westland petrels in acquiring that waste compared to other scavenging species, is needed in order to better predict the effect of a reduction in fisheries waste on Westland petrel population size.
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The importance of fisheries waste in the diet of Westland Petrels (Procellaria westlandica)Freeman, Amanda N. D. January 1997 (has links)
Westland petrels Procellaria westlandica breed only near Punakaiki on the West Coast of New Zealand. About 80 km offshore from their breeding colony, New Zealand's largest commercial fishery (for hoki Macruronus novaezelandiae) operates from mid June to early September, coinciding with the Westland petrel's breeding season. It has been assumed that Westland petrels feed extensively on fisheries waste and that this habit has been at least partly responsible for the increase in the Westland petrel population. Some seabird biologists have expressed concern that if a species comes to depend on scavenging at fishing vessels, such a species could experience a food crisis if fishing operations changed in a way that reduced the quantity of waste discharged. The aim of this research was to assess how dependent Westland petrels have become on fisheries waste for food. Diet studies showed that during the hoki fishing season, waste accounts for more than half by weight of the solid food Westland petrels bring back to the colony to feed their chicks. After the hoki season, waste contributes only about a quarter of their diet as birds switch to more natural prey and scavenge a wider variety of fish species presumably from smaller, inshore fishing vessels. Much of the fisheries waste eaten by Westland petrels was flesh which could not be identified using traditional techniques. The electrophoretic technique iso-electric focusing increased the number of fish samples that could be identified and consequently the diet was interpreted differently than it would have been had only traditional diet analysis been used. The survey of Westland petrel distribution off the west coast of the South Island, found that although hoki fishing vessels influence the distribution of Westland petrels, only a small proportion of the Westland petrel population appears to utilise this food resource at any one time. Westland petrels were tracked at sea by VHF radio telemetry and then by satellite tracking. Satellite tracking showed that there is considerable variation in the amount of time Westland petrels spend in the vicinity of fishing vessels. On average, satellite tracked birds spent one third of their time near vessels, but they foraged over much larger areas than that occupied by the West Coast South Island hoki fishing fleet. Although fisheries waste is an important component of the Westland petrel diet, it appears that the situation is one of opportunistic use of a readily available resource, rather than one of dependence. Several features of the Westland petrel's breeding biology and foraging ecology suggest that Westland petrels could compensate for a reduction in waste from the hoki fishery by switching to other sources of waste and increasing their consumption of natural prey. Nevertheless, much remains unanswered concerning the role of fisheries waste in the Westland petrel's diet. In particular, quantifying the waste available to seabirds, and the success of Westland petrels in acquiring that waste compared to other scavenging species, is needed in order to better predict the effect of a reduction in fisheries waste on Westland petrel population size.
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