La question du transbordement maritime des migrants - en transit à travers l'Atlantique - s'est constituée en problématique humanitaire internationale au début du XXe siècle. Elle fait notamment ...l'objet d'une mobilisation importante dans la société italienne, où les emigrants à destination de l'Amérique sont en grand nombre et se trouvent souvent piégés dans des formes graves de dépendance économique à l'égard des agents d'émigration qui les recrutent et des compagnies maritimes qui les transportent. Analyser comment l'Italie s'est efforcée d'élaborer un dispositif d'action publique pour encadrer et protéger sa population en partance pour l'Amérique, particulièrement dans l'espace-temps très spécifique qu'est la traversée maritime, permet de reconsidérer plusieurs enjeux mis au jour par les études consacrées aux migrations internationales, au gouvernement des populations et à la mondialisation marchande. Tout en rappelant le rôle très actif qu'eurent certains pays d'origine dans la protection de leur ressortissants migrants, ce cas montre que le sort de ceux-ci ne se jouait pas dans le seul face à face entre États émetteur et récepteur, mais aussi dans la nécessaire régulation du marché du transbordement, et tout autant dans l'opposition et l'arbitrage entre des acteurs et des intérêts divergents à l'intérieur même de la société italienne. The maritime transshipment of migrants across the Atlantic became an international humanitarian issue at the beginning of the 20th century. It inspired a widespread mobilization in Italian society, where many emigrants to America found themselves trapped in serious forms of economic dependency on the emigration agents who recruited them and the maritime companies who transported them. An analysis of the ways Italy attempted to elaborate modes of public intervention to supervise and protect its emigrating citizens, particularly in the specific space-time of maritime travel, sheds new light on several issues prominent in studies of international migrations, of population government and of commercial globalization. While recalling the very active role certain countries played in the protection of their emigrating citizens, the Italian case underlines that the fate of these migrants was played out not only in the confrontation between an issuing State anda receiving State, but also in the necessary regulation of the transshipment market as well as in the opposition (and resulting arbitration) between the parties and the diverging interests within Italian society itself
La fin du XIXe siècle marque moins l'apparition d'une gestion étatique de la migration que son changement de régime. La « protection du travail national » par le développement de l'identification et ...des barrières aux frontières vient se substituer à une régulation ex post fondée sur l'utilitarisme et la subsidiante (sauf à bénéficier d'une protection sociale communale, les étrangers tombant dans l'indigence étaient menacés d'expulsion). À l'avènement de cette xénophobie institutionnelle, les réformateurs sociaux, bientôt relayés par le Bureau international du Travail, opposent la signature de traités bilatéraux et de conventions internationales rapprochant les droits sociaux des migrants -chômage, retraite, contrat de travail, etc. -de ceux des nationaux. Tout en ayant permis le développement des assurances sociales et de I'État-providence, ces engagements transnationaux interrogent l'exercice de la souveraineté étatique, selon des modalités perpétuées de nos jours par le recours au traité de Gotha de 1851 pour administrer les flux de réfugiés. The late nineteenth century in Europe saw less the apparition of state management of migrations than a change of system. The "protection of national labor" through identification techniques and border control came to replace the older regime of ex post facto regulation based on the notions of usefulness and subsidiarity (foreigners could be expelled if destitute and ineligible for local welfare). In reaction to this new institutional xenophobia, social reformers, soon helped by the International Labour Office, pushed for bilateral treaties and international conventions guaranteeing migrants similar rights (for unemployment, old-age pensions, labour protections, and so on) as nationals. These transnational negotiations helped the emergence of the welfare state; they also put in a new perspective the practice of state sovereignty in an area where the Treaty of Gotha of 1851 is still regularly invoked to manage refugee flows.
People of European descent form the bulk of the population in most of the temperate zones of the world - North America, Australia and New Zealand. The military successes of European imperialism are ...easy to explain; in many cases they were a matter of firearms against spears. But as Alfred W. Crosby maintains in this highly original and fascinating book, the Europeans' displacement and replacement of the native peoples in the temperate zones was more a matter of biology than of military conquest. European organisms had certain decisive advantages over their New World and Australian counterparts. The spread of European disease, flora and fauna went hand in hand with the growth of populations. Consequently, these imperialists became proprietors of the most important agricultural lands in the world. In the second edition, Crosby revisits his now classic work and again evaluates the global historical importance of European ecological expansion.
Using individual tags combined with a fish fence operated at the mouth of Smith-Dorrien Creek, the primary spawning habitat for Lower Kananaskis Lake bull trout (Salvelinus confluentus), we ...approximated a complete census of the spawning population from 1996 to 2000 to assess whether timing of upstream and downstream spawning migrations varied with extrinsic and intrinsic factors. The timing of both upstream and downstream migrations varied with sex, previous spawning experience, density, and temperature. Inferred spawning duration based on the predicted upstream and downstream migration dates indicated that experienced female spawners spent the least amount of time upstream and first-time spawners spent the most time upstream. No consistent differences in upstream migration timing were observed between non-repetitive and repetitive spawners. We suggest that variations in spawning migration timing observed in Lower Kananaskis Lake may be linked to environmental factors that influence upstream swimming ability and acquisition and expenditure of energy with respect to reproduction.
This volume offers a systematic survey of migration histories in the central transition zone between Africa, Asia and Europe from the 4th to the 15th century C.E.
Bibliographic analysis about the migratory flows to the Amazon region between the XVIII andXX centuries is the focus of this article. Thus, the cultural crossings resulting from the displacements are ...able to expose the differentiated processes of interculturalities (Candau, 2016) of those social phenomena of migrations in various temporalities. The purpose of this study is to glimpse the manifestations of religious nessas intersections between migrant subjects from different spaces and temporalities. Critical method (Bloch, 2001) was used to analyze the sources, highlighting two results: to identify the links between religious cultural nexuses and gaps, and to expose elements of religious (in)tolerance present in the context of the intercultural Amazons. The refore, the interculturality constituted in the historical context of migration and the transits of cultures denote the dynamism of continuous and discontinuous movements of cultural "nexuses" and "gaps", particularly religious ones that expose the conflicting "moral" values of the narratives/discourses.
The European eel (Anguilla anguilla) is critically endangered (according to the most recent IUCN assessment) and has suffered a 95% decline in recruitment since the 1980s, attributed in part to ...factors occurring during the marine phases of its life-cycle. As an adult, the European eel undertakes the longest spawning migration of all anguillid eels, a distance of 5000 to 10,000 km across the Atlantic Ocean to the Sargasso Sea. However, despite the passage of almost 100 years since Johannes Schmidt proposed the Sargasso Sea as the breeding place of European eels on the basis of larval surveys, no eggs or spawning adults have ever been sampled there to confirm this. Fundamental questions therefore remain about the oceanic migration of adult eels, including navigation mechanisms, the routes taken, timings of arrival, swimming speed and spawning locations. We attached satellite tags to 26 eels from rivers in the Azores archipelago and tracked them for periods between 40 and 366 days at speeds between 3 and 12 km day
, and provide the first direct evidence of adult European eels reaching their presumed breeding place in the Sargasso Sea.
Conceptualizing detention Mountz, Alison; Coddington, Kate; Catania, R. Tina ...
Progress in human geography,
08/2013, Letnik:
37, Številka:
4
Journal Article
Recenzirano
Detention is a pressing empirical, conceptual, and political issue. Detained populations, detention facilities, and industries have expanded globally. Detention is also a fundamentally geographical ...topic, yet largely overlooked by geographers. We argue that detention be conceptualized as a series of geographical processes. Operating through these processes are contradictory sets of temporal and spatial logics that structure the seemingly paradoxical geographies underpinning detention. These logics include containment and mobility, bordering and exclusion. We trace these logics through an emergent literature, synthesizing and analyzing important geographic themes in the field. We identify contributions by and new avenues of inquiry for geographers.
Anthropogenic reductions in riverine connectivity can severely impede the migrations of anadromous species. In fragmented rivers, successful migrations depend on the ability of migrants to negotiate ...barriers or locate alternative passage routes. However, individual variation in the specific aspects of movement that determine migration success in fragmented rivers, is poorly characterised.
Here, individual variation was investigated in the spawning migrations of 56 adult sea lamprey Petromyzon marinus, an anadromous, semelparous species that does not show fidelity to natal rivers. The variability and consequences of two key aspects of fish migration within fragmented rivers were tested: passage time (total time taken to pass a barrier) and retreats (exploratory downstream movements after unsuccessful passage attempts). These were tested using acoustic telemetry in the highly fragmented River Severn catchment, western England, U.K.
Distinct unimodal, bimodal, and multimodal patterns of variation in passage times were displayed across the different barriers, potentially related to the physical characteristics of the barrier and prevailing river discharge conditions when the barriers were first approached, but were not related to lamprey body sizes. At the first three barriers encountered by upstream‐migrating sea lamprey in the study, between 30% and 46% of individuals made retreat movements, and between 5% and 100% of retreating individuals were able to locate alternative tributaries. Retreating individuals were highly variable in their distance and frequency of retreats; overall, retreat movements comprised 11% (lower‐upper quartiles 0%–52%, range 0%–76%) of the total distance moved before reaching spawning areas. Time‐to‐event analysis indicated that retreat rates reduced as river discharge increased.
There was no evidence indicating that individual variation in passage time, or presence of retreat movements at barriers, influenced the subsequent upstream migration speed or final upstream extent of lampreys. While predictability in rank arrival timing was high within three unobstructed reaches, this predictability was disrupted at barriers due to individual variation in passage times.
Anthropogenic barriers thus can both disrupt and reveal individual variation in the migration dynamics of anadromous species. Substantial variability in retreat behaviours can be displayed by anadromous species facing delays at barriers, with these behaviours also associated with environmental conditions and the availability of alternative migration routes. Individual variation in exploration and passage time of migrants strongly influence their eventual spawning distribution.
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