Dissertations / Theses on the topic 'Migratory movements'

Conference: 16th International Conference, CAAD Futures 2015 - "The next city". São Paulo, Brazil, July 8-10, 2015, At São Paulo, Brazil., Volume: Computer-Aided Architectural Design Futures. The Next City - New Technologies and the Future of the Built Environment ( Communications in Computer and Information Science, Volume 527 - 2015)<br>The present paper is a mapping study of digital fabrication laboratories in Latin America. It presents and discusses results from a survey with 31 universities’ fab labs, studios and independent initiatives in Latin America. The objective of this study is fourfold: firstly, to draw the cultural, social and economic context of implementation of digital fabrication laboratories in the region; secondly, to synthesize relevant data from correlations between organizational structures, facilities and technologies, activities, types of prototypes, uses and areas of application; thirdly, to draw a network of people and institutions, recovering connections and the genealogy of these fab labs; and fourthly, to present some fab labs that are intertwined with local questions. The results obtained indicate a complex “homo faber” network of initiatives that embraces academic investigations, architectural developments, industry applications, artistic propositions and actions in social processes.

Entre les moltes comunitats migratòries existents al món, aquesta tesi doctoral estudia fonamentalment la comunitat dels ciutadans i ciutadanes pakistanesos que viuen a Catalunya, i també sobre les xarxes que han establert per consolidar i expandir la seva presència. <br/>Aquesta tesi a més a més, estudia la situació de les famílies i de les comunitats d'origen al Pakistan per entendre millor els processos que han conduit cap a aquest fenomen migratori, la situació actual de la població pakistanesa a Catalunya, l'impacte de la migració en les famílies dels migrants al Pakistan i les perspectives a curt i mitjà termini d'aquest moviment de població. <br/>La comunitat pakistanesa a Catalunya presenta un cas d'estudi interessant, no pel fet migratori en sí mateix, sinó perquè aquest moviment migratori té lloc sense que existissin lligams culturals, històrics i lingüístics previs entre el Pakistan i Catalunya, i perquè l'expansió ha estat molt ràpida en aquests darrers anys. <br/>Un segon objectiu d'aquesta tesi és donar veu als participants en el projecte d'investigació i, a través d'ells, a la comunitat pakistanesa a Catalunya i a les seves famílies i comunitats d'origen. <br/>Durant la segona meitat del segle vint, es van desenvolupar vàries teories, models i sistemes per intentar explicar la migració internacional. La realitat social i econòmica de la població pakistanesa a Catalunya i de les seves famílies en el Pakistan però, no s'hi ajusta gaire. Ara bé, totes elles contenen elements que poden ajudar a la comprensió del fenomen migratori i per tant convé considerar-les com un conjunt d'instruments que ajuden a capturar (no és incorrecta però la trobo un pèl forçada: copsar? captar? comprendre? ) una realitat complexa i constantment canviant. <br/>La investigació ha permès de concloure que l'emigració pakistanesa a Catalunya està fonamentada en el diferencial econòmic entre els dos països, un diferencial que compensa els costos de la migració. La gran majoria de la població pakistanesa a Catalunya hi tenien una "àncora" abans de venir. L' origen comú de molts d'ells indica l'existència de xarxes migratòries basades en la relació familiar i/o social. <br/>L'objectiu principal dels migrants és poder oferir una vida millor a les famílies, un objectiu a mitjà i llarg termini, atès que l'objectiu inicial consisteix en recuperar la inversió que suposa per a cada família enviar un dels seus a Catalunya. Facilitar l'arribada de nous immigrants no sembla ser un objectiu, sinó que és un fet que succeeix sense que es busqui. <br/>Catalunya no és pas la destinació preferida dels migrants. La seva arribada és més aviat el resultat d'una curosa anàlisi cost/benefici en el sentit que Catalunya constitueix una destinació "fàcil" i "bé de preu". <br/>En resum, es pot dir que la migració pakistanesa a Catalunya continuarà augmentant en els propers anys amb l'arribada principalment d'homes, però també de dones i nens i nenes, sempre i quan les condicions econòmiques i polítiques continuïn més o menys igual. Aquest creixement farà que els enclavaments pakistanesos a la ciutat de Barcelona s'enforteixin. Alhora, sorgiran altres enclavaments a la mateixa ciutat i a la zona metropolitana, i possiblement també a Girona i Tarragona, i més tard a Lleida. Aquests enclavaments funcionaran com un pol d'atracció per a nous migrants pakistanesos. <br/>És molt possible que, seguint el model de migració pakistanesa a altres països europeus, els migrants pakistanesos s'esforcin per integrar-se en el món econòmic, però només els individus amb un nivell educatiu alt estaran disposats a desenvolupar lligams culturals i socials amb els catalans. La majoria de la població pakistanesa preferirà viure al marge de la societat catalana. <br/>Tot i que molts voldrien tornar al Pakistan, és probable que la majoria romangui a Catalunya definitivament i amb la seva presència contribueixi a l'expansió continuada del moviment migratori pakistanès a traves de l'enfortiment de les xarxes migratòries i dels enclavaments pakistanesos.<br>Among the many migrant communities in the world, this doctoral dissertation focuses on the Pakistani community in Catalonia and the networks they have established to consolidate and expand their presence there. <br/>In addition, this thesis studies the situation of families and the communities of origin in Pakistan to try to understand the processes that have led to this migratory phenomenon, the present situation of the Pakistani population in Catalonia, the impact of migration on their families in Pakistan, and the short and medium term prospects for this migratory movement. <br/>The Pakistani community in Catalonia presents an interesting case study not because of the migratory movement itself, rather because the movement takes place in the absence of cultural, historical or linguistic links between Pakistan and Catalonia, and because of its fast expansion. A second objective is to give voice to the participants in the research and through them, to the Pakistani community in Catalonia and their families and communities of origin. <br/>During the second half of the 20th century, many theories, models and systems were developed to try to explain international migration. However these theories fail to explain the social and economic reality of the Pakistani population in Catalonia and their families in Pakistan. Nonetheless, they may help understand the migratory phenomenon, and therefore they may be used as a set of instruments that help capture a complex and constantly changing reality. <br/>The research shows that Pakistanis migrate to Catalonia prompted by the economic differential between the two countries and the perceived low risks/costs attached to it. The great majority of Pakistanis in Catalonia had an anchor before proceeding, be it a friend, a relative or even an acquaintance, that was crucial in facilitating their arrival and initial introduction. The common geographical origin of most of them shows the existence of migratory networks based on family and social relations. <br/>The overall objective is to provide more and better for their families. But this is a medium or long term objective. Initially most of them need to recoup their or their family's initial investment to send them abroad, and only afterwards they can start saving for their families. Facilitating the arrival of other migrants is not an objective per se, bur rather an unintended effect. <br/>Catalonia is not the migrants' preferred destination. The research findings indicate that the choice was made on the basis of a cost benefit analysis, i.e. they selected the destination which was the least costly and which brought the greatest benefits in the short term. <br/>In summary, in the coming years Pakistani migration to Catalonia will continue and will probably grow exponentially through the arrival of mostly men, but also women and children, as long as economic and political conditions remain the same, or experience only minor variations. This growth will lead to the strengthening of existing Pakistani enclaves in Barcelona city, and the emergence of new ones in Barcelona and in the Metropolitan Area of Barcelona, and to a lesser degree in Girona, Tarragona and eventually Lleida. These enclaves will function as a pull factor attracting many more Pakistanis to Catalonia. <br/>Based on the research findings and the experience of Pakistani migratory movements to other European destinations, Pakistani immigrants are likely to remain separate from the local population. Their desire to integrate will focus on the economic sphere, and only a few, better educated individuals, will be ready to establish and develop cultural and social links with the Catalan society. There is likely to be a strong resistance to adopt any mores of the host society and particularly to merge with it. <br/>Despite their longing for Pakistan and Pakistani society, the majority of them will remain in Catalonia and will settle here, thus sustaining the Pakistani migratory movement and contributing to its expansion through the strengthening of existing enclaves and the emergence of new ones.

The postbreeding period in migratory bird species is an important, but often neglected,area of knowledge. From May-October of 1993-95, I studied the breeding andpostbreeding ecology of 61 adults and postfledging movement of 43 juveniles in aradio-tagged population of Wood Thrushes (Hylocichla mustelina) on the U. S. MarineCorps Base, Quantico, Virginia (38 30' N, 77 25' W). Fledglings became independent 0 0from their parents at 28-36 days post hatching and dispersed 307-5300 m from their natalsites to join flocks of conspecifics. About half (46%) of the young birds stayed in onedispersal site until migrating, but the rest visited other sites. In 40 instances, 15fledglings moved up to 6 km out of the dispersal site and, after 1-5 days, returned to thelocality occupied before initiating the movement. After dispersal, fledglings' positions(n = 556) occurred in (1) second growth and sapling stage sites at the edge of forested areas [52%], (2) gypsy moth (Lymantria dispar) damaged deciduous forest [21.8%], (3)Virginia pine (Pinus virginianus) forest that had a heavy understory of young deciduous trees and an open canopy [15.6%], and (4) mature mixed forest [10.6%]. Most fledglings(73%) left the Marine Base in September at the mean age of 81 days. After finishing breeding, adult Wood Thrushes underwent molt that extended from late July to early October. Flight-feather molt lasted on average 38 days and may have impaired flight efficiency in some individuals. Of 30 observed adults, 15 molted in the same area where they nested, and 15 moved 545 to 7290 m from their nesting sites. Molting sites were located in areas with a larger number of pines, less canopy cover, fewer trees with dbh>38 cm, and a denser understory strata than nesting sites (P < 0.1). My data suggest that a conservation strategy that focuses on identifying and protecting nesting habitat in the temperate region, although important, is incomplete at best if the events and needs during the post reproductive and post fledging periods are not considered.<br>Ph. D.

Stable isotopes of carbon (813C ), nitrogen (615N) and hydrogen (62H ) and microsatellite markers were used in conjunction with morphological data, to test whether breeding origins of two migratory passerines the Blackbird Turdus merula, and Redwing T iliacus, overwintering in the UK & Ireland could be predicted, based on data collected at European breeding sites. Geographical trends of feather 62H and 613C values of birds sampleda t Europeanb reeding sites were useful for determining breeding origins of Blackbirds at a broad geographical scale. Genetic markers were useful for discriminating between the two Redwing races iliacus and coburni. Conversely, no genetic structure was found within the nominate race iliacus and there was only weak genetic structure in Blackbird populations, suggesting relatively high gene flow. These results indicate that genetic markers are of limited value for population assigm-nenot f either species. Mean wing length of breeding Blackbirds differed significantly between breeding regions, and was positively correlated with latitude, suggesting that wing length is potentially a useful variable for discriminating between Blackbirds of different breeding origin. It was predicted that combining techniques would prove substantially more useful for assigning individuals to their most likely origin, than any one technique used in isolation. For Blackbirds, the combination of 62H and 813C values with wing length proved to be the most effective combination of variables (and was more effective than using either stable isotopes or wing length alone), allowing 72.2% to 76.3% of breeding Blackbirds to be correctly and consistently assigned to one of three broad geographic regions (UK, Fennoscandia and Continent). For Redwings, using DNA markers alone, 94.5% of birds were correctly assigned to either the coburni or iliacus; the addition of stable isotopes produced only a marginal improvement. Useful insights into the contrasting migratory strategies of Blackbirds and Redwings were revealed. The lack of genetic variation within the nominate Redwing race indicates a lack of migratory connectivity. In contrast, weak genetic population structure in the Blackbird, and differences in stable isotope i ratios and wing length between birds sampled at different wintering sites, suggests that different parts of the UK & Ireland may receive differing proportions of migrant Blackbirds originating from different breeding sites. This suggestst hat migratory connectivity might be strongeri n this species. The approach of using multiple techniques may prove useful for other species about which less is known regarding breeding origins, which may be particularly relevant for species of conservati on concern. However, the most useful variable/combination of different variables for a study of migratory connectivity will vary, both according to the species, its geographical range, and the scale of resolution required, and a clear understanding of the ecology and physiology of the study species is essential.

The aim of this thesis is to provide a critical framework for addressing the use of the moving image in contemporary art that studies geography through the experiences of the mobile body and the use of a mobile camera. The research focuses on artistic practices that use video narratives to experiment with and explore contemporary dimensions of economic migration and cultural movement as a topic in which contemporary artists are engaged, either in representing their own movements or in observing those of others. Through the analysis of this complex field, the text argues that particular moving image works produce new cartographies of both urban space and also social relations within these territories of change and encounter. My research focuses on contemporary artists' use of video in several related ways. Video recording may be used as a primary research t061 for first-hand encounters reflecting the empirical aspect of traditional documentary practices as knowledge gathering procedures. T have examined what T term the 'analytical inscription' of video as articulat~d through the artist's subjective experience specifically in terms of the production of visual narratives based on primary 'source material'. These narratives can take the form of what has been recently named video essays, or they can be examples of narrative construction placed in a cinematic narrative and video installation environment. My practice seeks to bridge the objectivity of documentary and the subjectivity of the essay by articulating my experiences as filmmaker through narrative construction drawing on the experiences of 'others'. The thesis text attempts to contextualize my practice by relating contemporary theories of urban space and new geographies to the specificities of contemporary artists' uses of the moving image and the mobility enabled by video technology.

L’Arctique, bien que région éloignée de toutes activités anthropiques intensives, est contaminé par les polluants émis à de plus basses latitudes. En effet, les caractéristiques physico-chimiques de certains polluants leur permettent d’être transportés sur de longues distances, via les courants atmosphériques ou océaniques. Parmi eux se trouve notamment le mercure (Hg), élément trace non-essentiel naturellement émis dans l’environnement mais dont les émissions d’origine anthropiques ont fortement augmenté depuis le 19ème siècle. Ce neurotoxique engendre chez les espèces animales des troubles comportementaux, mais aussi des problèmes de reproduction et dans les cas extrêmes, la mort. Le milieu marin est particulièrement sensible à la contamination au Hg. En effet, une fois dans l’environnement marin, le Hg intègre la chaine alimentaire (sous sa forme toxique méthylée - MeHg), dans laquelle sa concentration augmente d’un niveau trophique à l’autre (processus de bioamplification) et/ou accumule au sein des organismes (processus de bioaccumulation). Ainsi, les prédateurs supérieurs longévifs tels que les oiseaux marins, en fin de chaine alimentaire, présentent les concentrations de Hg parmi les plus élevées. Ils sont largement et efficacement utilisés comme bio-indicateurs de la contamination au Hg de leur environnement. La majeure partie des connaissances actuelle sur la contamination au Hg des oiseaux marins Arctique concerne la saison de reproduction, durant laquelle les concentrations varient spatialement, avec notamment les concentrations les plus élevées trouvées en Arctique Canadien. Durant cette période, qui ne représente qu’une partie de l’année, les oiseaux se reproduisent à terre et sont donc plus facilement accessibles. Mais une fois la saison de reproduction terminée, la majorité des oiseaux marins migrent en haute mer, en dehors de l’Arctique. Une étude précédente a montré qu’une population de mergules nains (Alle alle) se reproduisant à l’Est du Groenland a des concentrations de Hg plus élevées en période de non-reproduction qu’en période de reproduction, avec des effets délétères sur la reproduction suivante. Au cours de ce travail de thèse, et grâce à une approche multi espèces et multi colonies, nous nous sommes intéressés au rôle de la migration des oiseaux marins sur leur contamination au Hg et ce à l’échelle de l’Arctique. Nos résultats montrent une saisonnalité dans la contamination au Hg, nous permettant d’étendre les résultats mis en avant pour les mergules nains à de nombreuses autres espèces d’oiseaux marins. Nous avons également trouvé que cette saisonnalité varie spatialement avec des variations saisonnières plus importantes pour les populations se reproduisant en Atlantique Ouest (Ouest du Groenland et Est du Canada). Ces résultats nous ont amenés à faire l’hypothèse que cette variation était une conséquence de la migration des oiseaux marins et de la distribution de leur zone d’hivernage. Pour tester cette hypothèse, nous avons utilisé les oiseaux comme bio-indicateurs de leur environnement. Pour cela, nous avons combiné des analyses de Hg avec du biologging afin de retracer l’origine spatiale de la contamination hivernale au Hg. Nos résultats montrent une augmentation des concentrations de Hg suivant un gradient est-ouest nous permettant ainsi d’étendre les résultats des précédentes études concernant la période de reproduction à l’hiver et à l’ensemble des régions marines à l’échelle de l’Atlantique Nord - Arctique. Ainsi, les résultats du présent travail de thèse nous permettent de conclure qu’au-delà de leur migration, ce sont les zones de reproduction et d’hivernages des oiseaux marins arctiques qui conditionnent leur contamination au Hg<br>The Arctic, even far from intensive human activities, is contaminated by pollutants emitted at Northern mid-latitudes. Because of their physico-chemical characteristics, pollutants are transported over large distances through atmospheric or oceanic currents. Among them is mercury (Hg), a naturally occurring and non-essential trace element whose emissions increased since the 19th century because of human activities. This neurotoxic negatively impacts animals’ health and induces behavioral changes, reproduction issues and in the most extreme case, death. The marine environment is particularly sensitive to Hg, which incorporates the food chain (under is toxic and methylated form – MeHg) in which its concentration increases from one trophic level to the other (e.g. biomagnification process) and accumulates within organisms (e.g. bioaccumulation process). Hence, long-lived top predators like seabirds, found at the end of the food chain usually show some of the highest contamination to Hg. They are commonly and efficiently used as bio-indicators of the health of their environment. Most of the current knowledge about Hg contamination in Arctic seabirds focused on the breeding period during which Hg was found to spatially vary, with usually higher Hg concentrations in the Canadian Arctic. During this period, which represents a part of the year only, seabirds aggregate in colonies for reproduction where they are more easily accessible. However, at the end of this period, seabirds migrate to overwinter mostly in open seas, outside of the Arctic. A previous study on a little auk (Alle alle) population breeding in East Greenland found that Hg concentrations were higher during the non-breeding period than during the breeding period, with carryover effects on the following reproduction. In the present doctoral work, based on a multi-species and multi-colony approach, we studied winter Hg exposure and the role of seabird migration in their contamination to Hg at large spatial scale. We found a seasonality in Hg concentrations allowing us to extend the results found in little auks to several species and at a larger spatial scale. We also found that this seasonality was spatially different with some of the highest variations for seabirds breeding in the West Atlantic (West Greenland and Canadian Arctic). We therefore proposed that such variations were due to seabird’s migration and the areas they overwintered at. To test such hypotheses, we used seabirds as bio-indicators of winter Hg contamination through the North-Atlantic Arctic. More specifically, we combined Hg measurements with geolocators devices to track the spatial origin of winter Hg contamination. We found an east-west increase in Hg concentrations allowing us to extend the results found during the breeding period to the winter period, through the entire North-Atlantic Arctic marine region. Results of the present doctoral work allow us to conclude that beyond migration, seabird distribution during the breeding and non-breeding periods drive their contamination to Hg

Large population declines for sand tiger sharks (Carcharias taurus) in parts of its global range are well documented, resulting in a strong need for biologically informed conservation and management measures. Although sand tigers in the western North Atlantic have been listed as a Species of Concern by the US government since 1997, details of their seasonal migratory movements and especially vertical habitat use patterns along the US East Coast are limited. Understanding these movement patterns is vital to reducing fishery-related mortality of these sharks and informing other management efforts aimed at recovery of their stocks in the US Atlantic. Although survey and fishery-dependent data have revealed a general picture of the seasonal distribution patterns of sand tiger sharks, details of the areas specifically used by these sharks and their movements between such areas remain unclear. Additionally, information on vertical habitat use such as preferred depth and temperature, as well as variability observed among sexes, size classes and geographic locations would provide insight into the fine-scale distribution of sand tigers to aid better management practices. Here, I report on the horizontal and vertical movements of sand tiger sharks along the US East Coast determined through use of pop-up archival transmitter (PAT) tags and supplemental acoustic telemetry. PAT tags were deployed on 14 sand tiger sharks in Delaware Bay in late summer 2008. Sufficient archived depth and temperature data were obtained from 11 sharks (eight male, three female), and sufficient light data allowed construction of long-term horizontal tracks for 10 sharks (seven male, three female) using a Kalman filter state-space model. Duration of tag deployment per animal ranged from 64-154 days ( =121.6). All seven male sharks left Delaware Bay in late summer/early autumn and migrated south along the US East Coast reaching waters off North Carolina, where they remained until transmitter detachment during the winter months. In contrast, all three females moved out of Delaware Bay into deeper, offshore waters east of the bay near the continental slope. During southern migration of males, average depth utilized was positively correlated to shark size. The smallest males spent on average over 90% of their time in waters <40 >m, whereas intermediate and large sized males spent only 54 and 38% of their time at depths <40 >m, respectively. Female sharks spent an average of 46% of their time in waters range, spending at least 95% of their time in waters 17-23oC, with little difference between size classes or sexes. Horizontal movements of male migrating sand tigers also revealed several areas of concentrated activity along their southern migratory routes. Migratory patterns of sand tiger sharks along the US East Coast appear most similar to patterns displayed by this species along the coast of South America. Further delineation of western North Atlantic continental shelf and slope core areas of sand tiger shark activity, especially for females, will inform efforts to reduce interactions with commercial fisheries and measures to avoid habitat degradation - management aspects that will aid in reducing mortality and enhance rebuilding of sand tiger stocks along the US East Coast.

The European eel is a mysterious animal and has a life cycle which has fascinated biologists for centuries. However many basic aspects of its life cycle and migrations remain unknown. European eels play a pivotal role in a balanced ecosystem both as a predator and prey species thus, understanding important ecological aspects of eel behaviour while resident in continental waters is vital in safeguarding and enhancing existing stocks. In recent years we have witnessed declines in juvenile eel recruitment across Europe. Results from this thesis indicate a drastic decline in yellow eel abundance in a transitional water body in Northern Ireland between 1967 and 2013, with current levels at 3.38% of historical levels in the Foyle estuary. Many populations across Europe are thought to be reduced to approximately 10% of their size in the yellow eel growth phase of their life-cycle and juvenile recruitment to this phase is as low as 5% compared with 30 years ago. However, the continental phase in which eels spend up to 30 years before undertaking their spawning migration allows managers to direct effective conservation strategies. The existence of two morphotypes “broad-headed” and “narrow-headed” in the European eel has been historically documented and this discrete head shape variation has interested biologists across Europe for a considerable amount of time. This phenotypic variation is widespread across the panmictic eel population. The findings presented in this thesis have highlighted the importance of understanding the ecology of alternative phenotypes which can exist in European eels co-occurring within the same habitat, and results suggest there may be potential consequences on life history as a result of foraging strategy undertaken in a growth habitat, with varying lipid stores and growth rates found between individuals. These alternative foraging strategies’ which manifest themselves in head shape variability corresponded to significant variation in space use and activity patterns in lacustrine growth habitat. This provides the first empirical evidence that observed morphological variation leads to significant differences in movement behaviour. Feeding specialisations during the eel growth phase can have important consequences for population dynamics. Feeding strategies may incur greater risks from, for example, parasites. Intensity levels of the invasive nematode parasite Anguillicola crassus were associated with differences in ontogeny and trophic ecology. Infestation levels of parasites in affected fish revealed a significant negative relationship between fish length and parasite intensity, with smaller individuals having higher parasite intensity than larger individuals. This study indicates that food intake and infection risk are linked in the host-parasite system. The growth phase for eels in continental waters ends with a transition called “the silvering process” following which individuals begin migrating downstream towards marine waters to undertake their spawning migration to the Sargasso Sea. Understanding migration behaviour, life stage specific mortality and migration success at this important life stage, is critical to effective conservation management. The unimpeded downstream movement patterns and migration success of small female and male silver eels investigated during this study revealed a low success rate to open ocean. Only 26% of eels which initiated downstream migration were detected at the outermost end of an acoustic array located at the mouth of a sea lough. Telemetry equipment functioned efficiently at all locations, therefore this suggests high levels of mortality during sea lough migration, or less likely, long-term sea lough residence by silver eel emigrants. The overall research approach employed in this study i.e the combination of morphometric, stable isotope analysis and telemetry has allowed vital information to be gathered. Managers can utilise this information to employ appropriate conservation strategies for Anguilla anguilla as well as guiding future research directions.

In recent years, human decision-making has led to significant landscape impacts in the western United States. Specifically, migratory wildlife populations have increasingly been impacted by rural urban development and energy resource development. This research presents the application of agent-based modeling to explore how such impacts influence the characteristics of migratory animal movement, focusing on mule deer (Odocoileus hemionus) in Western Wyoming. This study utilizes complex adaptive systems and agent-based modeling frameworks to increase understanding of migratory patterns in a changing landscape and explores thresholds of interference to migration patterns due to increased habitat degradation and fragmentation. The agent-based model utilizes GPS-collar data to examine how individual processes lead to population-level patterns of movement and adaptation. The assessment incorporates elements from both human and natural systems to explore potential future scenarios for human development in the natural landscape and incorporates adaptive behaviors, as well as animal-movement ecology, in changing landscapes.

The blue shark (Prionace glauca) is among the most abundant and widely distributed of all oceanic elasmobranchs. Millions of blue sharks are caught annually worldwide in pelagic long line fisheries, and it accounts for the largest component of auctioned fin weight in the international shark fin trade. There is growing concern about the depletion of its populations worldwide and impacts of such large scale removal of an apex predator on oceanic ecosystem stability. The fragmentary nature of life history information available for blue sharks, including on its detailed movement and migratory behavior, continues to limit management efforts that require such data for stock assessment and sustainable catch modeling. To assist in obtaining a better understanding of blue shark movement behavior in the western north Atlantic, I used satellite telemetry to investigate the detailed habitat utilization and movements of sharks during the summer months when the sharks form aggregations on the continental shelf off the Northeast United States, and during their fall , pelagic migrations. Thirty-one (26 male, 5 female) blue sharks were tagged with pop-up archival satellite transmitters. The transmitters reported data from a total of 1,656 combined days, yielding 74,163 depth recordings and 74,125 temperature recordings. Tracked sharks exhibited two distinct movement patterns: During the summer months, the sharks remained within a restricted geographical area south of Nantucket Island and spent nearly 80% of their time in the uppermost part of the water column in <20 m depth (mean depth of 8 m). During fall months (October and November) the sharks made fairly directed offshore and southerly movements, with several sharks associating with waters east of Bermuda. During their pelagic migrations, the sharks demonstrated markedly different water column utilization behavior. They occupied much greater depths (127 m mean depth) and exhibited a clear diel depth pattern, occupying deeper water during the day and shallower water at night, not observed on the shelf. The longest duration track was that of an immature female for nine months. The greatest distance traveled was by a mature male that moved from Martha's Vineyard, MA to waters near Puerto Rico (a linear distance > 4,000 km). There was some indication that the different demographic groups (mature males, immature males, and immature females) may display different movement behavior, especially during their pelagic migrations. This study provides the first detailed information on habitat utilization and movement patterns of blue sharks in the Western North Atlantic, and points to the need for further investigation of movement behavior by different demographic segments of the population.

Intracellular microelectrodes have been used in conjunction with ion substitution, and agonists and inhibitors of known transport processes to investigate the mechanisms whereby ions cross the basal and apical cell membranes of the Malpighian tubules of Locusta. Values for basal, apical and transepithelial potentials in 'Normal' saline were -71.6 ± 0.3 mV, -82.6 ± 0.8 mV and +5.7 ± 1.0 mV (lumen positive) respectively. Ion substitution experiments, involving Na(^+),K(^+) and C1(^-) in the bathing media, indicated that the basal membrane was more permeable to K(^+) than Na(^+) and C1(^-). Two different electrical responses to high [K(^+)](_o) saline (the Type A and Type B response) were noted and these probably reflect distinct physiological states of basal membrane permeability. Experiments with ouabain and vanadate suggested that whilst Na(^+)+K(^+) ATPase activity, which has been demonstrated in microsomal preparations, was not significantly electrogenic, asymmetric ionic distribution across the basal membrane was partly maintained by thisenzyme Furthermore, 3-H ouabain-binding studies indicated that Na(^+)+K(^+) exchange 'pump' turnover was adequate to account for substantial entry and Na^ exit across the basal membrane. The electrochemicalgradient across the apical membrane suggests that exit from the cell must involve an active process with CI following passively. Data from ion substitution experiments and treatment with furosemide and bumetanide suggest that CI entry across the basalmembrane may be via cotransport with Na^ and/or K^. However, the+ —differential electrical responses to Na(^+) free and C1(^-) free salines question the role of Na(^+) in this process. The effects of c AMP, Ca(^2+) substitution and various inhibitors on basal and apical membrane potentials, taken in conjunction with the results referred to above, are discussed and a hypothetical model proposed whereby changes in intracellular Ca(^2+) and c AMP effect control of ion movements across the two cell surfaces.

Intracellular microelectrodes were used in conjunction with ion substitution, agonists and inhibitors of known transport processes and diuretic hormone (DH), to investigate the mechanisms whereby ions cross the basal and apical cell membranes of the Malpighian tubules of Locusta migratoria, and their endocrine control. Values for basal, apical and transepithelial potentials in control saline were -70.4 + 0.9 mV, -76.1 ± 1.5 mV and +5.5 ± 1.3 mV (lumen positive), respectively (n=73).Ion substitution experiments, involving K(^+), Na(^+) and CI(^-) in the bathing medium, indicated that the basal membrane is more permeable to K(^+) than Na(^+) and CI(^-). Ion flux studies suggest that CI(^-) entry across the basal membrane is not by direct cotransport with K(^+), nor Na(^+). Some CI(^-) entry also appears to be stimulated under conditions of high K(^+)(_o). Crude corpus cardiacum (CC) preparations with DH activity effected ca. 150% increase in tubular fluid secretion above basal secretion in vitro, and ca. 106% and 335% increase in net transepithelial Na(^+) and Cl(^-) movement from bathing medium to lumen above basal flux, respectively. Treatment of tubules with CC extract also resulted in a significant increase in levels of the intracellular second messengers, cAMP and the Ca(^2+)-mobilizing Inositol 1,4,5- trisphosphate. Ion substitution experiments using dibutyryl cAMP suggest that cAMP stimulates an apical cation pump, whilst having no effect on Cl(^-) conductance. Cytochemical localization and membrane separation techniques used in conjunction with biochemical analyses indicate the presence of (Na(^+)+K(^+))-ATPase on the basolateral membranes, and HCO(_3)- stimulated ATPase on both the basolateral and apical membranes. The results referred to above are discussed, and a hypothetical model is proposed to describe the endocrine control of ion movements across the two cell membranes mediated by changes in intracellular cAMP and Ca(^2+).

Anthropogenic structures such as dams, weirs, sluices, and hydropower facilities fragment river networks and restrict the movement of aquatic biota. The critically endangered European eel (Anguilla anguilla) migrates between marine and freshwater habitats and has undergone severe population decline. Barriers to migration are one of the negative impacts to be addressed for compliance with the EC Council Regulation for recovery of eel stocks. This thesis examines measures to reduce the effects of riverine structures on eel and improve passage facilities for both juvenile upstream and adult downstream migrating lifestages of this comparatively understudied species. The influence of turbulent attraction flow on eels ascending passage facilities was quantified at an intertidal weir. Plunging flow resulted in a two-fold increase in the number of eels using a pass. The behavioural mechanisms underlying this attraction, and wider questions of how eels respond to elevated water velocity and turbulent conditions found at barriers and fish passes were further investigated within a field flume. Eels showed a similarly strong attraction to turbulent areas, though adopted an energy conservation strategy by adjusting swim path to reduce the magnitude of velocity and turbulence encountered. Compensatory swimming speed was also used to reduce exposure to energetically expensive environments. Management recommendations are made to optimise the attraction of eels to pass facilities, yet ensure hydrodynamic conditions within the pass do not deter ascent. Legislative drivers also stipulate targets for seaward escapement of adult spawner stock. The impacts of multiple low head barriers and water abstraction intakes on route choice, delay, entrainment and escapement were quantified in a heavily regulated sub-catchment using telemetry. Entrainment loss at a single abstraction point was the biggest cause of reduced escapement, and was influenced by pumping regimes and management of intertidal structures. Delays at some structures were substantial (up to 68.5days), and reflected water management practices and environmental conditions. Sub-metre positioning telemetry allowed detailed behaviour of adult eel to be further quantified in relation to physical and hydrodynamic features at a hydropower intake. There was predominance of milling and thigmotactic behaviours at lower velocities (0.15 – 0.71 m s-1), whereas rejection occurred on encountering the higher water velocities and abrupt velocity gradients associated with flow constriction near the intake entrance. Information presented has implications for wider catchment management and highlights the potential to reduce barrier impacts through manipulation of structures and abstraction regimes. Quantifying eel behaviour in response to physical and hydrodynamic environments will aid the development of attraction, guidance and passage technologies.

I evaluated the influence of inter-wetland distance and the timing of drawdowns on local daily survival (residency) and movement probability of Semipalmated Sandpipers (Calidris pusilla) during the springs of 2006 and 2007 at the Tom Yawkey Wildlife Center (YWC), South Carolina. There is growing interest in determining the scale at which coastal wetlands are functionally connected and how management influences their use by migrant shorebirds. Parameters of interest were estimated using multi-state models and encounter histories obtained from resight and telemetry data. Data were collected in the spatial context of three clusters of multiple wetland units each separated by distances of 2.6 to 4.1 km and two hydrologic treatments--a slow and fast draw down. Mean length of stay was 2.99 d (95% CIs = 2.45 - 3.52) in 2006 and 4.57 d (95% CIs = 2.59 ? 8.92) in 2007. Residency probability was influenced by a negative and significant interaction between estimated percent fat at capture and southerly wind speed. This meant that differences in departure rates by birds with varying body conditions were minimized. Sixty-five percent of all marked birds stayed within 2 km from their banding location. Movement probabilities were negatively related to inter-cluster distance and bird density. In the spatial context of YWC there was functional connectivity among the clusters that were ~2.5 km apart; movement was negligible between units at nearly twice that distance (4.1 km). Contrary to expectations, the average probability of surviving and not moving for birds in slow-managed units was higher than birds in fast-managed units (PhiSS 2006 = 0.488, PhiSS 2007 = 0.654). On average, birds marked in fast-managed units moved out at high rates (Psi 2006 = 0.399, Psi 2007 = 0.467). Higher prey biomass and bird density in slow-managed units influenced observed residency and movement rates. My findings advocate for conservation strategies that identify functionally connected wetland units and suggested that habitat supplementation for shorebirds during peak migration can be met by carefully planned staggered, slow drawdowns. The effectiveness of fast drawdowns is vulnerable to differential prey base quality, presence of birds on previously exposed habitat, failure of water control structures to operate properly, and the possibility of mismatching peak migration and rapid drawdown implementation.

Le déplacement animal joue un rôle déterminant dans la structuration spatiale et la dynamique des populations biologiques, en particulier des espèces fortement mobiles. L’espace et l’environnement font ainsi partie intégrante du cycle de vie des tortues marines. Ce travail de thèse propose de caractériser l’écologie spatiale des tortues marines, du stade juvénile au stade adulte, dans le Sud-ouest de l’océan Indien, principalement par l’usage de deux méthodes : la télémétrie satellitaire et la modélisation individu-centrée. Il montre en premier lieu que la phénologie de la reproduction de la tortue verte à travers la région est principalement liée à la température de surface de la mer au voisinage des sites de reproduction. Sont ensuite étudiés les patrons de dérive des nouveau-nés générés par les courants océaniques qui impacteraient inégalement leurs traits d’histoire de vie selon l’emplacement du site de naissance. Concernant le stade immature, les résultats suggèrent un cycle de développement trans-équatorial pour la tortue caouanne dans l’océan Indien. Pour le stade adulte, cette étude caractérise les couloirs et la connectivité migratoires de la tortue verte dans la région. Enfin, l’intégration de ces résultats permet de comprendre la structuration des patrons migratoires régionaux et leur influence sur la dynamique des populations. L’ensemble des connaissances acquises fournit un support concret d’aide à la décision pour la mise en place de plans de gestion et de conservation des tortues marines dans le Sud-ouest de l’océan Indien. Cela souligne l’importance d’une approche à grande échelle pour la protection d’un patrimoine biologique partagé par plusieurs nations<br>Animal movement is crucial to the ecology of spatially structured population, particularly for highly mobile species. Marine turtles’ life cycle is indeed closely related to spatial and environmental factors. This work analyses the spatial ecology of marine turtles, from early juvenile to adult stages, in the Southwest Indian Ocean, primarily through the use of two methods: satellite tracking and individual-based modeling. Firstly, this analysis argues that green turtle’s reproductive phenology across the region is mainly related to the sea surface temperature in the vicinity of the nesting site. Then, it shows how drifting trajectories of hatchlings in oceanic currents unevenly influence their life history traits depending on the position of the natal site. By tracking late juvenile stage, this work also suggests a trans-equatorial developmental cycle for loggerhead turtle in the Indian Ocean. At adult stage, it describes migratory corridors and connectivity for green turtle across the region. Finally, an integrative approach considering all these results allows for an understanding of the regional migratory patterns and their influence on population dynamics. The results of this work provide a practical policy decision tool for management and conservation of marine turtles in the Southwest Indian Ocean and highlight the need for a large-scale approach in the protection of biological resources and heritage shared by multiple nations

碩士<br>東吳大學<br>社會學系<br>102<br>This thesis is based on the researcher’s favorable interests towards Japanese pop-music and culture. We tried to find out the reason through our listening experiences to understand what construct the researcher’s Japanese enthusiasm. We gathered the distribution data of modern music locations in Seimonchō and used the Geographic Information System mapping, making text data visualize. We analyzed and explained it in the viewpoint of sociology and quoted “Thirdspace” theory (Edward Soja’s) and “the flâneur” concept (Walter Benjamin), trying to involve ourselves with the fan culture, and to investigate the relation between modern Japanese music fans and the entire Seimonchō area and the last one: how do they demonstrate its unique feature and put it into practice. Looking back on the history of Taipei city, we found out that from Japanese colonial period to the postwar time, Seimonchō has always been playing an important role in entertainment and music industries. Though after the Sino-Japan War, Japanese songs, movies and any form of audiovisual products were banned, some of them, secretly still kept active. Even now Seimonchō still serves as a wonderland for purchasing Japanese pop culture goods, peripheral products of young idols, and clothing. The way it aims at its potential consumer groups and how it displays the goods basically resemble that the street "Takeshita-dōri" does; however, the interview of the research indicates that Seimonchō is not the reflection of any part of Japan but the combination of past, present and future moments. The richness of its culture that derived from the Japanese colonial period has till now overcome the limitation of the boundaries and transformed itself into so-called “psudo-mix blood space” with the covering of Japanese street appearance. Those who are fascinated with Japanese music and goods flock in and out Seimonchō, trying to satisfy both their desire for shopping and for making exotic connections. This research related these J-Pop fans to biologically called “the migratory fish” which build relations with Japan through shopping experiences and online browsing (sort of virtual walks). It has successfully eliminated the limitation of linear time from the colonial period to current time and put an end to the first, second, and third space, resulting in a featured undivided heterotopias. Seimonchō has been providing plenty of brick and mortar businesses for J-Pop fans to keep up with the trend of music and entertainment. If incidentally knocking at the door of heterotopias, the fans are associating Seimonchō with Japan; and by the experiences that gain from shopping and wandering indeed enhance the fans’ desire to go back to Japan.

Most migrating songbirds are required to stopover to rest and replenish their fat reserves, and suitable stopover habitat is vitally important to their survival and success securing territories at their breeding and wintering grounds. Identifying and protecting stopover locations and movement corridors is essential to connecting all life stages of these species, yet there remain significant knowledge gaps regarding the utilization of stopover sites and fine-scale movements during migration, particularly at inland stopover areas. We investigated the factors that influence stopover duration and migration rate of ten migratory songbirds within the Silvio O. Conte National Fish and Wildlife Refuge in the Northeastern United States during two fall and spring seasons in 2015 and 2016 at 5 banding sites using automated telemetry. We expected that fat and mass would influence stopover duration and migration rate, in that birds with larger fat stores and greater masses would make shorter stopovers, and migrate faster than leaner birds. We also expected that birds would move faster in spring, and minimize time later in the season, by making shorter stopovers and migrating faster as the season progresses. A lower percentage of our focal species departed the banding sites within 24 hours compared to other studies in coastal and urban sites, indicating that more birds made stopovers. Sixteen percent of birds made prolonged stopovers (> 7 days) in spring, and 38 % in fall, highlighting the importance of the refuge for long term refueling. Spring birds made shorter stopovers, and traveled at faster rates than fall birds, suggesting there is may be more pressure for early arrival at breeding grounds. Spring birds captured with significant fat loads made shorter stopovers, and traveled faster than leaner birds. Spring birds also appeared to employ a time minimization strategy, with birds captured later in the season making shorter stopovers. Migration rate of spring birds decreased with distance from the capture site, indicating many birds needed to make additional stopovers. Fall birds that made longer stopovers migrated at faster rates. Fall birds captured later in the season made longer stopovers, and subsequently traveled at faster rates once they departed to possibly minimize time on migration. Variation in stopover behavior was evident among sites and species and this may suggest habitat or site characteristics that affect their value for migrating birds, which should be taken into consideration when conservation planning or vulnerable species. The extensive use of this inland National fish and wildlife refuge by migratory birds, and the fact that birds are acquiring energy reserves that are facilitating successful migration suggests this region is an important corridor for migrating songbirds.

Neurons perform complex computations, communications and precise transmissions of information in the form of action potentials (APs). The high level of heterogeneity and complexity at all levels of organization within a neuron and the functional requirement of highly permeable cell membranes leave neurons exposed to damage when energy levels are insufficient for the active maintenance of ionic gradients. When energy is limiting the ionic gradient across a neuron’s cell membrane risks being dissipated which can have dire consequences. Other researchers have advocated “generalized channel arrest” and/or “spike arrest” as a means of reducing the neuronal permeability allowing neurons to adjust the demands placed on their electrogenic pumps to lower levels of energy supply. I investigated the consequences of hypoxia on the propagation of a train of APs down the length of a fast conducting axon capable of transmitting APs at very high frequencies. Under normoxic conditions I found that APs show conduction velocities and instantaneous frequencies nearly double that of neurons experiencing energy limiting hypoxic conditions. I show that hypoxia affects AP conduction differently for different lengths of axon and for APs of different instantaneous frequencies. Action potentials of high instantaneous frequency in branching lengths of axon within ganglia were delayed more significantly than those in non-branching lengths contained within the connective and fail preferentially in branching axon. I found that octopamine attenuates the effects of hypoxia on AP propagation for the branching length of axon but has no effect on the non-branching length of axon. Additionally, for energetically stable cells, application of the anti-diabetic medication metformin or the hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker ZD7288 resulted in a reduced performance similar to that seen in neurons experiencing energetic stress. Furthermore both metformin and ZD7288 affect the shape of individual APs within an AP train as well as the original temporal sequence of the AP train, which encodes behaviourally relevant information. I propose that the reduced performance observed in an energetically compromised cell represents an adaptive mechanism employed by neurons in order to maintain the integrity of their highly heterogeneous and complex organization during periods of reduced energy supply.<br>Thesis (Master, Biology) -- Queen's University, 2011-10-07 14:41:46.972