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Abstract Background To understand the ecology of long-distance migrant bird species, it is necessary to study their full annual cycle, including migratory routes and stopovers. This is especially important for species in high-elevation habitats that are particularly vulnerable to environmental change. Here, we investigated both local and global movements during all parts of the annual cycle in a small trans-Saharan migratory bird breeding at high elevation. Methods Recently, multi-sensor geolocators have opened new research opportunities in small-sized migratory organisms. We tagged Northern Wheatears Oenanthe oenanthe from the central-European Alpine population with loggers recording atmospheric pressure and light intensity. We modelled migration routes and identified stopover and non-breeding sites by correlating the atmospheric pressure measured on the birds with global atmospheric pressure data. Furthermore, we compared barrier-crossing flights with other migratory flights and studied the movement behaviour throughout the annual cycle. Results All eight tracked individuals crossed the Mediterranean Sea, using islands for short stops, and made longer stopovers in the Atlas highlands. Single non-breeding sites were used during the entire boreal winter and were all located in the same region of the Sahel. Spring migration was recorded for four individuals with similar or slightly different routes compared to autumn. Migratory flights were typically nocturnal and characterized by fluctuating altitudes, frequently reaching 2000 to 4000 m a.s.l, with a maximum of up to 5150 m. Barrier-crossing flights, i.e., over the sea and the Sahara, were longer, higher, and faster compared to flights above favourable stopover habitat. In addition, we detected two types of altitudinal movements at the breeding site. Unexpected regular diel uphill movements were undertaken from the breeding territories towards nearby roosting sites at cliffs, while regional scale movements took place in response to local meteorological conditions during the pre-breeding period. Conclusion Our data inform on both local and global scale movements, providing new insights into migratory behaviour and local movements in small songbirds. This calls for a wider use of multi-sensor loggers in songbird migration research, especially for investigating both local and global movements in the same individuals.

Background: To understand the ecology of long-distance migrant bird species, it is necessary to study their full annual cycle, including migratory routes and stopovers. This is especially important for species in high-elevation habitats that are particularly vulnerable to environmental change. Here, we investigated both local and global movements during all parts of the annual cycle in a small trans-Saharan migratory bird breeding at high elevation. Methods: Recently, multi-sensor geolocators have opened new research opportunities in small-sized migratory organisms. We tagged Northern Wheatears Oenanthe oenanthe from the central-European Alpine population with loggers recording atmospheric pressure and light intensity. We modelled migration routes and identified stopover and non-breeding sites by correlating the atmospheric pressure measured on the birds with global atmospheric pressure data. Furthermore, we compared barrier-crossing flights with other migratory flights and studied the movement behaviour throughout the annual cycle. Results: All eight tracked individuals crossed the Mediterranean Sea, using islands for short stops, and made longer stopovers in the Atlas highlands. Single non-breeding sites were used during the entire boreal winter and were all located in the same region of the Sahel. Spring migration was recorded for four individuals with similar or slightly different routes compared to autumn. Migratory flights were typically nocturnal and characterized by fluctuating altitudes, frequently reaching 2000 to 4000 m a.s.l, with a maximum of up to 5150 m. Barrier-crossing flights, i.e., over the sea and the Sahara, were longer, higher, and faster compared to flights above favourable stopover habitat. In addition, we detected two types of altitudinal movements at the breeding site. Unexpected regular diel uphill movements were undertaken from the breeding territories towards nearby roosting sites at cliffs, while regional scale movements took place in response to local meteorological conditions during the pre-breeding period. Conclusion: Our data inform on both local and global scale movements, providing new insights into migratory behaviour and local movements in small songbirds. This calls for a wider use of multi-sensor loggers in songbird migration research, especially for investigating both local and global movements in the same individuals. [ABSTRACT FROM AUTHOR]

Calliptamus italicus (Linnaeus, 1758) is a polyphagous grasshopper widely distributed from Europe to central Asia, known to perform long-range migrations during its gregarious phase, especially in the eastern part of its range. In the Alps, this species mostly occurs in dry grassland habitats in valley floors or on well-exposed slopes, usually establishing resident populations below 2000 m, but information on its dispersal patterns in this geographical area are still lacking. This short note reports an unusual observation of C. italicus at high eleva- tion (3050 m) in the Cottian Alps, with a description of the associated local habitat features and short-term weather conditions. Although based on a single record, hypotheses on the possible underlying dispersal processes are provided, discussing whether this observation may represent or not a first evidence of a migration behaviour by Italian locusts across the Alpine ridge. The performance of either a local movement or a long-range migration is firstly hypothesized, due to the apparent suitability of the short-term weather conditions (i.e. no rain, increase in temperatures and wind intensity). However, since the specimen was missing the left hind leg, thus potentially compro- mising its dispersal capacity, a third hypothesis of an animal- or human-mediated transport is also considered. Given that the available data are not sufficient to definitely ascertain whether C. italicus is able to disperse in autonomy across the Alps or not, further records are needed in future to verify the hypotheses presented here and to enhance the detail of the environmental variables possibly involved.

Calliptamus italicus (Linnaeus, 1758) is a polyphagous grasshopper widely distributed from Europe to central Asia, known to perform long-range migrations during its gregarious phase, especially in the eastern part of its range. In the Alps, this species mostly occurs in dry grassland habitats in valley floors or on well-exposed slopes, usually establishing resident populations below 2000 m, but information on its dispersal patterns in this geographical area are still lacking. This short note reports an unusual observation of C. italicus at high elevation (3050 m) in the Cottian Alps, with a description of the associated local habitat features and short-term weather conditions. Although based on a single record, hypotheses on the possible underlying dispersal processes are provided, discussing whether this observation may represent or not a first evidence of a migration behaviour by Italian locusts across the Alpine ridge. The performance of either a local movement or a long-range migration is firstly hypothesized, due to the apparent suitability of the short-term weather conditions (i.e. no rain, increase in temperatures and wind intensity). However, since the specimen was missing the left hind leg, thus potentially compromising its dispersal capacity, a third hypothesis of an animal- or human-mediated transport is also considered. Given that the available data are not sufficient to definitely ascertain whether C. italicus is able to disperse in autonomy across the Alps or not, further records are needed in future to verify the hypotheses presented here and to enhance the detail of the environmental variables possibly involved. [ABSTRACT FROM AUTHOR]

Bonefish (Albula vulpes) is a socioeconomically important species that supports a data-poor recreational fishery in developing countries. Understanding how environmental variables influence its abundance and movement is important for better decision-making. This study used mark-recapture to examine the association between abiotic (temperature, salinity, wind speed, tides moon phase, and sediment coarseness) and biotic (presence of predators and bottom vegetation) variables with bonefish movement and abundance in Corozal-Chetumal bay and the adjacent Caribbean coast of southern Mexico and northern Belize. We used seines to capture bonefish, marked 9657 using dart tags and recaptured 595 fish (6.2% recapture rate) during 16 sample periods between January 2016 and February 2018. Marked bonefish size ranged 19.5–56.4 cm and recaptured 23.9–49.4 cm. Total abundance for each seine sample and distance between mark and recapture locations were used in two separate multiple stepwise regression analyses. Movement was negatively associated with temperature and predator presence, while sediment coarseness and moon phase were positively associated. Temperature increases were associated with short-distance movements. Temperature decreases and high-illumination lunar phases were associated with longer-distance movement and likely related to spawning migrations. Presence of predators, like barracuda, was associated with low bonefish abundances and was likely an adaptive response to form multiple schools of low density by bonefish to avoid predation. These spatiotemporal movement and abundance patterns are recommended to be taken into account in fisheries and protected areas management and to inform the decision-making process in urban and tourism development in coastal habitats. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Estudios Internacionales Mediterraneos is the property of Taller de Estudios Internacionales Mediterraneos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Internal waves generate near bed cold water incursions. • The depth of these incursions is set by the regional stratification. • A strong positive IOD event deepened the thermocline to unprecedented depth. • Cold water incursions are highly localized in tropical atoll environments. • Internal wave generated turbulence may influence reef manta behaviour. Physical oceanographic observations were made with subsurface, taut-line moorings at Egmont Island, a tropical atoll within the Chagos Archipelago in the central Indian Ocean, to elucidate the dynamics of near-bed cold-water intrusions implicated in driving local aggregations of reef manta rays (Mobula alfredi). Manta have been previously shown to aggregate within 'Manta Alley', a lipped gully at 65 m depth along the north coast, at times when the surface to bottom temperature difference was highest. We here identify the dynamical processes driving these temperature differences and shaping the foraging landscape at Egmont, and equivalent small-scale atolls, improving our understanding of manta behavior at hotspots where they are most vulnerable to exploitation. The thermal regime within Manta Alley is shown to be governed at several spatiotemporal scales. The extreme 2019 Indian Ocean Dipole event drove a depression of the 26 °C isotherm to a depth of 115 m precluding the observation of cooling within the alley. As the thermocline shoaled with the change in phase of the IOD, near bed cold water flushing was seen with tidal periodicity within the gully. The internal tide is accompanied by high frequency internal waves with periods of O (5 min) which are shown to promote mixing through shear instability, evidenced by subcritical Richardson numbers, with surface-seabed temperature differences ∼4 °C observed throughout a tidal period. Our results highlight a level of heterogeneity in oceanographic dynamics at sub-atoll spatial scales within an environment in which these processes are rarely resolved. Whilst the physical mechanisms through which these dynamics drive foraging within the resident manta population remain unclear, the generation of turbulence by high frequency internal wave events as shown here may influence zooplankton distributions, improving feeding efficiency at discrete locations within atolls. Our results thus highlight the need to account for fine scale changes in oceanographic conditions when attempting to explain habitat utilization by mobile species. [ABSTRACT FROM AUTHOR]

Overflows that interrupt the ‘normal state of affairs’ are generative events that make visible the agential force of nonhumans. Practitioners of posthumanist disciplines - such as STS, ANT, economic performativity and animal studies - have exposed how nonhumans take part in the making of ‘the social.’ Due to their predominantly small-scale perspective, these efforts have left broader sociopolitical effects mainly unattended. Here I explore how the political agency of nonhumans can provoke sociopolitical consequences when approached through political ontological lenses. I argue that by conceiving reality as the precarious effect of struggles between competing ways of performing the world, human/nonhuman associations can be understood as part of non-dominant ontologies, revealing the world’s multiplicity and expanding the borders of political communities. To do so, I study a citizen/swans association that emerged in Valdivia, Chile, in response to a disaster that since 2004 has affected the Río Cruces wetland and its colony of swans, following the installation of a new pulp mill by Arauco. This unprecedented mobilization provoked the breakdown of Chile’s environmental framework and forced reform. I find that the suffering of the swans was ‘the’ most agentive force within the struggle, leading all sorts of actors to act in response. Based on an ontological reading of Rancière’s understanding of ‘the properly political’ and on Critchley’s notion of the ethical call that drives political action, I show how, through their ‘doings,’ the swans - previously unaccounted - became overtly political actors, ontologically reconfiguring the political community [ABSTRACT FROM AUTHOR]

Abstract: The habitat use of eels during the development of sedentary behavior, which depends on the animals’ body size, is unknown. Our objective was to analyze, for two years, the changes in the home range of a population of European eel (Anguilla anguilla, Linnaeus, 1758) in Southern Europe in relation to the animals’ body length (TL), and the influence of environmental factors (water temperature and flow) on the local movements of this population through observation of their sedentary behavior. We used a previously-validated mark−recapture methodology, obtaining a low deviation in the estimation of the extension of the eels’ movements. Our results revealed relatively short movements in relation to other populations, and we hypothesize that this could be related to the high habitat diversity and low eel population density in the study area. The home range size showed a high variability and dispersion among the smallest eels, however, as TL increased, the variability of home range size decreased, and home ranges were larger. These changes could be associated with the acquisition of a sedentary lifestyle. Once eels had become sedentary, an environmental pattern was observed between their movements and the water temperature and flow, with larger movements observed as the flow increased and water temperature decreased. This suggests that the temporal and spatial scales of observation are of crucial importance for monitoring eel populations and for the study of population size structure, population dynamics, and biology, which can be used to improve conservation strategies.

Summary This study addresses the question why a struggle emerges between local communities and mining MNCs. Many studies in the extant literature tend to explain the emergence of these struggles by relying on some “objective conditions” such as the characteristics of the industry, strategies of companies, features of community, and governmental policies. Drawing on Foucauldian and Laclauian insights, we argue that the analysis of such struggles should rather focus on meaning-making processes, through which each party to a struggle articulates surrounding conditions in particular ways, thereby giving shape to new meanings and identities. By comparatively examining Efemçukuru and Çöpler goldmine cases from Turkey, in which a struggle emerges in the former but not in the latter in spite of similar conditions, we demonstrate that the emergence of struggles is mainly due to the construction of rival discourses that construct the issues of mining, environment, and development in highly different ways. We argue that already-prevalent conditions play a role in the emergence of struggles to the extent that they are employed, framed, and reframed in the rival anti-mining and pro-mining discourses. The argument goes further that the availability of anti-mining discourse when the local meaning systems are dislocated by the arrival of MNCs, as well as its popular appeal at the local level are critical in the emergence of local mobilizations against gold-mining. Finally, emphasis is put on the relational nature of struggle processes, where anti-mining and pro-mining discourses are mutually constituted and reconstituted through a constant reformulation of hegemonic strategies. [ABSTRACT FROM AUTHOR]

This paper presents a genetic algorithm applied to the protein structure prediction in a hydrophobic-polar model on a cubic lattice. The proposed genetic algorithm is extended with crowding, clustering, repair, local search and opposition-based mechanisms. The crowding is responsible for maintaining the good solutions to the end of the evolutionary process while the clustering is used to divide a whole population into a number of subpopulations that can locate different good solutions. The repair mechanism transforms infeasible solutions to feasible solutions that do not occupy the lattice point for more than one monomer. In order to improve convergence speed the algorithm uses local search. This mechanism improves the quality of conformations with the local movement of one or two consecutive monomers through the entire conformation. The opposition-based mechanism is introduced to transform conformations to the opposite direction. In this way the algorithm easily improves good solutions on both sides of the sequence. The proposed algorithm was tested on a number of well-known hydrophobic-polar sequences. The obtained results show that the mechanisms employed improve the algorithm's performance and that our algorithm is superior to other state-of-the-art evolutionary and swarm algorithms. [ABSTRACT FROM AUTHOR]

Phymactis clematis Drayton es la especie de actinia más abundante y unas de las que alcanza mayor tamaño en la costa de Sudamérica. Al igual que en otras especies de actinias, los adultos de la especie poseerían una activa capacidad de realizar desplazamientos locales. Sin embargo estos no han sido adecuadamente descritos, desconociéndose los factores causales. En este trabajo pretendemos describir algunos patrones básicos asociados a la conducta de desplazamiento local en P. clematis, evaluados indirectamente a partir de la presencia de halos de roca desnuda alrededor de los individuos en dos sitios intermareales rocosos en la costa del norte de Chile (Cavancha y Colorado Chico). Los desplazamientos fueron más frecuentes y de mayor intensidad en Colorado Chico, donde más del 50 % de los individuos evidenciaron desplazamientos, aunque generalmente no superaron los 60 mm de extensión. En Colorado Chico, los desplazamientos ocurrieron principalmente en individuos con diámetro pedal superior a 40 mm, mientras que la intensidad de éstos decrecería con el tamaño. Discutimos que las causas del mayor desplazamiento de individuos en Colorado Chico podrían estar asociadas a la mayor abundancia y menor espaciamiento entre los individuos, los cuales derivarían en una interferencia física entre los individuos. De este modo sugerimos que los patrones asociados al tamaño de los individuos emergerían secundariamente, siendo supeditados al nivel de abundancia local. A pesar de que los desplazamientos de P. clematis en Colorado Chico ocurren en general a una escala de unos pocos centímetros, tendrían un efecto significativo en el espaciamiento interindividual, incrementando en promedio la distancia al vecino más próximo. Se plantea la posibilidad de que los desplazamientos locales serían un mecanismo efectivo de reducción de la competencia intraespecífica en P. clematisPhymactis clematis Drayton is the most abundant and one of the largest species of sea anemone along the South American coast. Likewise other sea anemone species, the adults of the P. clematis would have an active ability to make local movements. However, these have not been properly described, and causal factors are unknown. In this work we try to describe some of the basic patterns associated to the local movement behavior in P. clematis, assessed indirectly from the presence of bare rock halos around individuals in two rocky intertidal sites in the coast of northern Chile (Cavancha and Colorado Chico). Movements were more frequent and had a higher intensity at Colorado Chico, where over 50 % of individuals showed movements, although they were mainly lower than 60 mm in length. At Colorado Chico, movements would occur in individuals larger than 40 mm of pedal diameter, whereas their intensity would decrease with body size. We discussed that causes of higher movement activity at Colorado Chico could be associated to the higher abundance and lower inter-individual spacing, which would produce physical interference among individuals. In this way, we suggested that the patterns associated to the individual's body size would arise secondarily, being dependent on the levels of local abundance. Despite local movements of P. clematis at Colorado Chico occurred at a scale of a few centimeters, they could be affecting significantly the inter-individual spacing, increasing the average nearest neighbor distance. We argue that local movements could be an effective mechanism reducing the intraspecific competition in P. clematis

This article explores the local dimensions of movement work being done with regard to ostensibly global issues such as economic justice and environmental degradation. It is posited that local work focusing on peace/nonviolence and resilience/sustainability is often emphasized by virtue of necessity and efficacy alike. Issues of global import play out in myriad local contexts, and represent a point of convergence between peace and environmental movements. This analysis highlights the inherent connection between social and environmental issues, and between microcosmic and macrocosmic processes. It is concluded that small steps by networked actors can impact larger issues in a meaningful way. [ABSTRACT FROM AUTHOR]

Copyright of Latin American Perspectives is the property of Sage Publications Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study addresses how multinational corporations and protesters in an environmental struggle learn from the proximate struggles within the same field and how they structure the broader institutional field. Drawing on the literature integrating the social movement and new institutional theory, particularly the “strategic action fields” (SAFs) approach of Fligstein and McAdam, the authors comparatively study the interactions in and between two sequential environmental struggles in the field of gold mining in Turkey. The findings suggest that the interactive processes in an SAF and their consequences are largely built on the lessons drawn from both “successes” and “failures” in the proximate SAF that preceded it. Furthermore, those actors that act proactively are more likely to stabilize the SAF according to their interests. Finally, state interventions from the outside create temporary stability that involves the acquiescence of challengers, whereas the consent-seeking actions of incumbents are more likely to generate a permanent stability, stabilizing the broader field. [ABSTRACT FROM AUTHOR]

Abstract: Acoustic telemetry was used to study patterns of habitat use and movements of Pomatomus saltatrix L. (common name elf/shad/bluefish/tailor) within the Saldanha Bay with Langebaan Lagoon coastal embayment on the west coast of South Africa. Thirty six mature P. saltatrix were tagged with acoustic transmitters and released within the lagoon in May 2006 and November–December 2007, and their positions were monitored until late-November 2008 using 28 hydrophones positioned throughout the embayment. The detection pattern of P. saltatrix suggested a tendency to residence within the embayment throughout the thirty month long study period, with nearly 60% of released individuals only being detected within the lagoon in the inner part of the embayment. However, there was a long-term trend of movement from the lagoon into the bay. One individual was recaptured off the east coast of South Africa 21 months after being tagged, 1760 km away, suggesting that P. saltatrix are capable of undertaking long along-shore migrations. Over finer scales within the inner lagoon, P. saltatrix ground speed increased (1) with an increase in tidal current speed, (2) with an increase in photoperiod, and (3) during day. Pomatomus saltatrix tended to move seaward during ebb tides, and to occupy greater depths during day. [Copyright &y& Elsevier]