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El rayador (Rynchops niger) visita las costas de Chile durante los veranos australes, observándose en bandadas de distinto tamaño principalmente en humedales costeros. Por medio del uso de una base de datos de observaciones de ciencia ciudadana junto a nuestros monitoreos de largo plazo, estimamos que el tamaño poblacional promedio para la especie en Chile alcanzó los 10.227 individuos entre 2014 y 2018. Tres sitios (estuarios de los ríos Mataquito, Itata, y Tubul) congregaron a más del 50% de la población. El análisis de la abundancia relativa a través del año para cuatro macrozonas geográficas reflejaría el movimiento de la especie en las costas de Chile. La zona Norte muestra un peak de abundancia en noviembre con la llegada de individuos, no siendo tan clara su estrategia de retorno. Las zonas Centro-Norte y Centro del país muestran dos peaks en la llegada y partida de individuos, sugiriendo un uso más bien de tránsito. La existencia de un solo peak en el mes de febrero, además de las mayores concentraciones de individuos, indicarían que las zonas Centro-Sur y Sur del país serían potencialmente el destino para gran parte de la población de rayadores. El seguimiento de individuos por medio de radiotelemetría permitió detectar movimiento de individuos entre una red de humedales costeros. Estos desplazamientos ocurrirían frecuentemente a lo largo de toda la temporada y tanto en dirección norte como hacia el sur. Este trabajo presenta información relevante para la evaluación del estado de la especie en Chile, país que potencialmente alberga un porcentaje significativo de la población de la subespecie cinerascens durante el período no reproductivo.

This book, which forms part of the Cryptology and Information Security Series (CISS), presents the collected papers from the 2011 Workshop - 'RFIDsec'11 Asia' - on RFID security, co-hosted by Peking University and Penn State University in Wuxi, China, in April 2011. RFIDsec Asia is the Asian counterpart of the earlier RFID security workshop, RFIDsec, which was set up in 2005. It provides an Asia-based forum to address fundamental issues in theory and practice related to security and privacy issues, designs, standards and case studies in the development of radio frequency identification (RFID) systems, EPC global networks and the Internet of Things (IoT). The program of the 2011 workshop consists of one invited paper and a further nine papers, which were selected following a rigorous reviewing process by the Program Committee members and external reviewers. The papers cover many interesting topics in the realm of RFID security, including distance bounding and mutual authentication protocols, public key cryptography implementation and the Internet of Things.

This volume contains papers presented at the 2010 Workshop on Radio Frequency Identification Security (RFIDsec'10 Asia), held in Singapore on February 22-23, 2010. Twelve high-quality papers, including four invited papers, were selected after a rigorous reviewing process by the Program Committee members and external reviewers. The book covers many interesting topics, including unconditionally secure RFID systems, dynamic RFID tag authentication, RFID ownership transfer, fingerprinting RFID tags, and secure RFID-supported supply chains.

Tracking small‐ to large‐scale movements of animals is important for studying their interactions with the environment, including how they adjust and adapt their migration in response to environmental and human‐induced changes. Despite the technical progress in tracking devices, a major challenge remains for small animals—such as songbirds, bats and insects—because GPS transmitters are still too heavy to be carried by these lightweight species. Automated radio‐telemetry offers a lightweight, scalable alternative. However, unlike GPS, radio‐telemetry does not yield precise location data—only information about receiving antennas and the strength of detected signals. Existing localisation methods either rely solely on receiver locations, offer only small‐scale, site‐specific estimates or were less user‐friendly though already integrating antenna geometry, signal strength and spatiotemporal uncertainty, limiting their ability either to reconstruct full flight paths or to be easily applied by practitioners. We fill this gap by presenting movetrack, an R package that reconstructs animal trajectories from automated radio‐telemetry data—such as that collected by the Motus Wildlife Tracking System—using a hidden Markov model (HMM) framework. Our approach combines coarse geometric position estimates—based on antenna bearing and signal strength—with an HMM that accounts for measurement error, temporal gaps, and movement dynamics. The model distinguishes behavioural states such as migratory flight, local movement and stopovers by analysing directional persistence and speed of the animal. We validate movetrack using controlled low‐altitude aircraft flights, simultaneously recorded with GPS and radiotelemetry, to simulate migratory flights of aerial species. Our results convincingly demonstrate that movetrack produces biologically realistic flight path estimates with quantifiable uncertainty, enhancing localisation in telemetry‐based movement research. movetrack provides a straightforward and practical approach, without requiring enhanced mathematical knowledge, to precisely reconstruct flight movements in a high spatiotemporal resolution. The R package enables researchers and conservationists to better study the response of aerial animals to environmental change and, ultimately, to formulate more effective conservation measures, for instance in relation to potential conflicts with anthropogenic stressors, such as artificial light at night, pesticides and human‐made structures.

Snakebite envenoming is a major neglected tropical health issue. The high incidence of snakebites in tropical rural communities suggests that venomous snakes and people are often in proximity but quantitative evidence is lacking. I used radio-telemetry on a population of Russell’s vipers (Daboia russelii), one of the most medically important snakes in the world, to quantify proximity between this venomous snake and people and estimate susceptibility to snakebite envenoming in India. I observed people ≤50 m of a radio-equipped viper in ~17% of 2,066 snake relocations. People were more frequently observed in proximity to Russell’s vipers in January and July compared to March, but all other contrasts were statistically similar. This pattern indicates that snakebite incidence, which peaks in summer in the study area, is not particularly linked to the encounter frequency between people and vipers. However, consistent with epidemiological data plantation workers were the most at-risk part of the population. By integrating information about the locations of humans and snakes in space and time, this pioneering research highlights the need to include snake ecology into the study of the human–venomous-snake conflict, and provides a model approach to help mitigate the burden caused by venomous snakes in the rural Tropics

Pathogenic fungi have become a global concern to wildlife populations over the last 2 decades. However, the threat of snake fungal disease (SFD; caused by Ophidiomyces ophiodiicola) to snake populations is still largely unknown. From 2014–2016, we monitored 3 disjunct populations of the federally threated eastern massasauga (Sistrurus catenatus) in Michigan, USA. We used clinical signs of SFD, quantitative TaqMan polymerase chain reaction (qPCR), repeated sampling of individuals and sites, and single-season occupancy models to estimate site-specific prevalence of Ophidiomyces. Point estimates of Ophidiomyces prevalence in 2016 were larger at the northernmost study site (0.17, 95% CI = 0.04–0.50), where 17 of 34 snakes were implanted with radio-transmitters, and smaller at southern sites (0.03, 95% CI = 0.00–0.19). However, Ophidiomyces prevalence was not different between snakes with transmitters and snakes without transmitters. Swabbing snakes with 1 applicator resulted in a high probability of failure in detecting Ophidiomyces DNA for individuals with clinical signs of SFD and the probability was even higher for individuals without clinical signs of SFD. Repeated sampling of individuals reduced the probability of obtaining a false-negative qPCR result by 72% for snakes with clinical signs and 12% for snakes without clinical signs when we swabbed individuals with 5 applicators. We recommend resampling individuals and sites as a sampling design for estimating fine-scale, site-specific Ophidiomyces prevalence and population-level responses to SFD. If clinical signs are used as a surrogate for SFD, we recommend researchers standardize diagnosis of clinical signs of SFD by providing technicians adequate field training and educational materials, and minimize the number of observers recording clinical signs. We discourage the use of radio-telemetry methods where SFD occurs unless sterile surgical, handling, and equipment protocols can be ensured and the benefits to the population from such activities outweigh the increased health risks to individuals.

A major uncertainty in automated radio-telemetry studies of small birds is the detection range of receiving antennas. We compared simultaneous daytime detections (± 30 s) by automated and manual radio-telemetry to assess detection probability and the proportion of transmissions detected for birds on migratory stopover as a function of distance, foraging guild (Black-throated Blue Warblers, Setophaga caerulescens, and Yellow-rumped Warblers, Dendroica coronata coronata, represented mid-canopy foliage gleaners and White-throated Sparrows, Zonotrichia albicollis, represented a ground forager), habitat type, meteorological variables, tower antenna number (1-4), and the position of a bird relative to the receiving antenna's bearing (offset angle). Our study was conducted at a migratory stopover site in southern Ontario, Canada. Most detections were in dense to sparse forest, and all individuals were within 1.03 km of the automated receiving station. Daily detection probability was near 100% for both foraging guilds. However, within 30 s before and after a manual radio-telemetry location was made, detection probability and the proportion of transmissions detected by automated radio-telemetry declined with distance, was higher for warblers than sparrows, and was lowest for 90° offset angles. Our results suggest that when research goals do not require detections with high temporal frequency, e.g., estimation of departure date or daily departure probability, our study design had an effective detection range of at least 1 km. However, where temporal precision is required, e.g., to investigate movements and changes in activity levels during stopover, detection range was ~300 m for ground-foraging sparrows and 600 m for mid-canopy foraging warblers, which is much lower than the presumed detection range of antennas under optimal conditions (15 km). This corresponds to a spatial area of coverage for forest-dwelling birds of ~0.3-1.1 km² . Our results suggest that to optimally configure an automated radio-telemetry array at the regional scale, investigators should carefully consider detection range and its underlying covariates, including species type, the habitat matrix, and the orientation of antennas relative to preferred habitat. Una gran incertidumbre en los estudios automatizados de radio-telemetría en aves pequeñas es el rango de detección de las antenas receptoras. Comparamos las detecciones diurnas simultáneas (± 30 seg.) mediante radio-telemetría manual y automatizada para evaluar la probabilidad de detección y la proporción de transmisiones detectadas de aves en escala migratoria en función de la distancia, el gremio de alimentación (Setophaga caerulescens, Dendroica coronata coronata, representando a las espigadoras del follaje del dosel m y Zonotrichia albicollis, representó un buscador de alimento del suelo), tipo de hábitat, variables meteorológicas, número de antenas de la torre (1-4) y la posición de un ave en relación con el soporte de la antena receptora (ángulo de desplazamiento). Nuestro estudio se realizó en un sitio de parada migratoria en el sur de Ontario, Canadá. La mayoría de las detecciones se realizaron en bosques densos a dispersos, y todas las personas se encontraban a menos de 1.03 km de la estación receptora automática. La probabilidad de detección diaria fue cercana al 100% para ambos gremios de forrajeo. Sin embargo, dentro de los 30 segundos anteriores y posteriores a la ubicación de la radio-telemetría manual, la probabilidad de detección y la proporción de las transmisiones detectadas por la radio-telemetría automatizada disminuyeron con la distancia, fue mayor para las reinitas que para los gorriones y fue más baja para los ángulos de desplazamiento de 90°. Nuestros resultados sugieren que cuando los objetivos de la investigación no requieren detecciones con alta frecuencia temporal, por ejemplo, la estimación de la fecha de salida o la probabilidad de salida diaria, el diseño de nuestro estudio tuvo un rango de detección efectivo de al menos 1 km. Sin embargo, cuando se requiere precisión temporal, por ejemplo, para investigar los movimientos y cambios en los niveles de actividad durante la parada, el rango de detección fue de ~300 m para los gorriones que buscan alimento en el suelo y 600 m para las reinitas que buscan alimento en el dosel medio, que es mucho más bajo que la detección estimada de las antenas en condiciones óptimas (15 km). Esto corresponde a un área espacial de cobertura para aves que habitan en el bosque de ~0.3 a 1.1 km². Nuestros resultados sugieren que, para configurar de manera óptima un conjunto automatizado de radio-telemetría a escala regional, los investigadores deben considerar cuidadosamente el rango de detección y sus covariables subyacentes, incluido el tipo de especie, la matriz del hábitat y la orientación de las antenas en relación con el hábitat preferido

1. Information about when and where animals die is important to understand population regulation. In migratory animals, mortality might occur not only during the stationary periods (e.g. breeding and wintering) but also during the migration seasons. However, the relative importance of population limiting factors during different periods of the year remains poorly understood, and previous studies mainly relied on indirect evidence. 2. Here, we provide direct evidence about when and where migrants die by identifying cases of confirmed and probable deaths in three species of long-distance migratory raptors tracked by satellite telemetry. 3. We show that mortality rate was about six times higher during migration seasons than during stationary periods. However, total mortality was surprisingly similar between periods, which can be explained by the fact that risky migration periods are shorter than safer stationary periods. Nevertheless, more than half of the annual mortality occurred during migration. We also found spatiotemporal patterns in mortality: spring mortality occurred mainly in Africa in association with the crossing of the Sahara desert, while most mortality during autumn took place in Europe. 4. Our results strongly suggest that events during the migration seasons have an important impact on the population dynamics of long-distance migrants. We speculate that mortality during spring migration may account for short-term annual variation in survival and population sizes, while mortality during autumn migration may be more important for long-term population regulation (through density-dependent effects).

Detailed data on juvenile survival are rare in the literature. Although many studies estimate recruitment, if you cannot distinguish between permanent dispersal and mortality, the management implications for a population may be unclear. We estimated juvenile survival in a reintroduced North Island robin (Petroica longipes) population in a protected sanctuary surrounded by an unprotected landscape where the species is extirpated. The population has had marginal population growth due to poor recruitment so we modeled 3 types of data (resighting of fledglings, radio-telemetry of independent juveniles, resighting of adults) in an integrated framework to determine the life stages where high mortality was occurring, and to distinguish mortality from dispersal. Approximately 16% of birds that fledged (n = 109) were present at the start of the next breeding season, consistent with recruitment rates from previous years. Low survival in the first 6 weeks after fledging was the primary cause of poor recruitment. Only 50% survived to independence (4 weeks after fledging), and 18% survived to the end of the radio-tracking period (14 weeks), after which juvenile survival matched adult survival. No dispersal from the sanctuary occurred during the radio-tracking period. Juveniles moved between adjacent forest fragments within the sanctuary, but did not leave the sanctuary. This information, which demonstrates the importance of distinguishing between natal mortality and dispersal, is important for ongoing management of the site and selection of future reintroduction sites for this species.