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Platypuses are a unique freshwater mammal native to eastern Australia. They are semi‐aquatic, predominantly nocturnal, and nest in burrows dug into the banks of waterbodies. Quantifying nesting burrow characteristics is challenging due to the species' cryptic nature. We radio‐tagged 11 female platypuses during their breeding season (September to November) on the Snowy River, located their resting and nesting burrows by radiotracking, and assessed plasma triglyceride concentration as a biomarker of egg production. We quantified and tested for differences in height and distance from water of resting and nesting burrows, as well as for differences in both canopy and ground cover in the vicinity of resting and nesting burrows in comparison with background control sites in the area. Female platypuses displayed a strong selection for trees and shrubs, placing both their resting and nesting burrows within 5 m of these features. Compared with resting females, nesting females selected to dig nesting burrows higher above the river (nesting 1.98 m ± 0.27 SE vs. resting 1.15 m ± 0.10 SE) that were also further away from water (9.10 m ± 1.08 SE vs. 4.77 m ± 0.53 SE). Camera trap footage captured mice (Mus musculus) and black rats (Rattus rattus) entering two confirmed nesting tunnels on numerous occasions. During the first 3 weeks following the onset of nesting behaviour in two platypuses, rats entered the nesting tunnel a total of eight times and 31 times. Whether this is a previously unconsidered predator by invasive species remains to be evaluated. Synthesis: Riparian vegetation is a critical component of platypus habitat, providing stability for burrows, protection from predators, retaining high bank necessary to avoid inundation of burrows, and providing organic matter for nesting material and for abundant macroinvertebrate communities. Given ongoing declines and habitat degradation across their range, riparian habitat must be conserved and restored to promote breeding and population persistence. [ABSTRACT FROM AUTHOR]

Movement is a key mechanism influencing biodiversity patterns and ecosystem processes. Movement ecology aims to understand the causal relationships between environmental conditions, animal movements, interactions and coexistence of species, as well as effects of movement patterns on ecosystem processes. In contrast, practical conservation primarily aims to understand organisms' movements to improve species management, protection, legal monitoring or risk assessment, and species-habitat interactions. Despite the many studies of movement ecology in basic and applied sciences as well as in practical conservation in terrestrial ecosystems, knowledge gain and transfer between disciplines are limited. Better integration and linking of both disciplines would result in diverse science-practice synergies, but these are currently constrained by numerous challenges that need to be overcome. From a scientific perspective, knowledge gain from practice is limited by a multitude of case studies with limited spatial and temporal resolution. This can be overcome by improving access and combining the diversity of data for a research area that often deals with small sample sizes. From a practical perspective, the movement ecology framework, which is often dedicated to basic research, as well as the access and language barriers to scientific publications, limit the application of scientific results. Here movement ecologists should be encouraged to consider conservation issues more frequently in addition to basic research. The transfer of scientific results could be improved by scientists providing sufficient details for practitioners to extract relevant information and publish at least an open-access abstract in local language with clear management recommendations. Further, the use of open-access repositories allows both, scientists and practitioners an overview of the multitude of studies and helps to share data in order to derive general conclusions. Challenges impacting science and practice can be conceptual, organisational and technical in nature. Such constraints can be overcome, for example, by providing verified trapping protocols, using recent technological developments and analytical methods combined with trainings on these state-of-the-art tracking and analysing tools. In particular, collaborative project planning between scientists and practitioners can help to improve the sampling design of applied studies and broaden the data base for science in order to significantly advance the movement ecology framework and gain comprehensive knowledge for practical conservation. [ABSTRACT FROM AUTHOR]

To characterize the potential for exposure of amphibian terrestrial life stages to plant protection products (PPP), we studied the occurrence and habitat use of adult and metamorph common frogs (Rana temporaria) and common toads (Bufo bufo) in an agricultural landscape in Germany. The four selected study sites were breeding ponds with approximately 80% agricultural land within a 1‐km radius. Adults were monitored by radio tracking for two years, and metamorph numbers were assessed for one summer using pitfall traps alongside drift fences. The results demonstrate that adults were rarely present in arable fields at any of the sites (overall 0.5% and 4% of total observations for frogs and toads, respectively). Metamorph captures in arable fields were more variable, ranging from 1.2% to 38.8% (frogs) and from 0.0% to 26.1% (toads) across study sites. Unsurprisingly, most captures in arable fields for both toad and frog metamorphs occurred at the site where the pond was completely surrounded by arable fields. Overall, the presence of adult amphibians in arable fields was limited and, for the metamorphs, occurred primarily when crops were denser and PPP spray interception higher. Diurnal hiding behavior was observed with the highest activity recorded at night, further reducing the risk of dermal exposure from direct PPP overspraying. In addition, it appeared that alternative habitats, such as woody structures or water bodies in the broader surrounding area, were preferred by the animals over the arable areas. The use of buffer zones around water bodies in agricultural areas would be an effective risk mitigation measure to protect terrestrial adults and metamorphs residing there and would reduce spray drift entry into water bodies during PPP application. It is hoped that these results will contribute to the discussion of risk assessment and mitigation options for amphibians. Integr Environ Assess Manag 2024;20:2218–2230. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: Relevant potential exposure for both adult and metamorph anuran amphibians (i.e., common frogs and toads) on agricultural land was assessed.The movement and behavior of both adult and metamorph common frogs and common toads exhibited a preference for nonarable habitats and reduced potential for exposure.Landscape management is an option to protect and support amphibian populations effectively. [ABSTRACT FROM AUTHOR]

Post‐release monitoring is critical for assessing translocation outcomes. Yet the quality of information gained from monitoring can vary greatly, and perceived monitoring costs often results in reduced monitoring effort. Selecting cost‐effective monitoring strategies that provide high quality data are therefore important for assessing translocation outcomes and making informed management decisions.To compare how monitoring strategy affects information gained, we monitored a toutouwai/North Island robin (Petroica longipes) reintroduction in Aotearoa New Zealand, based on monitoring objectives of determining survival, site fidelity and whether the extent of management was large enough to protect dispersing individuals. We compared how these objectives were met through four monitoring strategies: (1) comprehensive surveys with ground radio telemetry and playback; (2) aerial drone telemetry; (3) dedicated playback by trained surveyors and (4) opportunistic playback by predator control contractors. We undertook a viewshed analysis to determine search coverage of each strategy and compared detection rates, efficiency and cost.Comprehensive ground telemetry and playback, while costly, covered the largest area and provided the most accurate data on dispersal, survival and the translocation outcome. In comparison, opportunistic playback monitoring detected substantially fewer individuals, giving a false impression of low site fidelity and survival and a failed translocation. Although drone telemetry had considerable site‐specific limitations, which limited its effectiveness during our study, it was the most cost‐effective with a high detection rate and low search effort.Synthesis and applications: Our study shows the value of intensive monitoring in facilitating management decisions for wildlife translocations. Comprehensive telemetry and playback, while costly, were invaluable for gaining high quality information on the translocation outcome. Without suitable monitoring, reintroduction outcomes can be difficult to assess and potentially result in unnecessary, ineffective or overly expensive management actions. We recommend that monitoring intensity and methodology should reflect the site, species and level of uncertainty regarding the translocation outcome. Prioritising monitoring can help reduce long‐term costs, increase quality of information gained and allow for more informed management decisions that can improve subsequent translocation outcomes. [ABSTRACT FROM AUTHOR]

The Gran Canaria Blue Chaffinch is the rarest forest passerine in the western Palaearctic with a population reduced to a single locality, Inagua, in the west of the island. After a forest fire, some birds were established in another location and a reinforcement programme was launched with the aim of consolidating this new population. Between 2010 and 2019, 194 Blue Chaffinches were released in the pine forest of La Cumbre, in the centre of the island and at a higher altitude than the previous one. Birds of two origins were used for this action: captive-bred birds were released using "soft" release methods, and wild-caught birds from the Inagua source population were released using "hard" release methods. Survival of radio-tagged birds (20–42 days of battery life) was high and similar between the two groups. Wild-caught birds occupied 12–15 times more surface area than captive-bred birds that remained close to supplementary feeding sites. All translocated birds displayed breeding behaviour in the following breeding season, although the rate of contribution to the new population was significantly lower for wild-caught birds (21% compared to 54% for captive-bred birds). This disparity can be partly attributed to nearly one-fifth of the wild-caught birds returning to Inagua. We conclude that the establishment phase of the Blue Chaffinch reinforced program in Gran Canaria has been successful. To retain wild-caught birds and deter their return to the source population, we recommend employing methods akin to the soft-release techniques utilized for captive-bred birds. Ongoing monitoring of the enhanced population, collecting data on survival and breeding success, will enable the evaluation of the long-term success of the translocation program. [ABSTRACT FROM AUTHOR]

One of the conservation efforts for the Komodo Dragon (Varanus komodoensis) is the translocation of the Komodo. Six juvenile captive-bred Komodo Dragons were translocated from Bogor to Wae Wuul Nature Reserve, East Nusa Tenggara Province, on 23rd September 2023. This research aims to calculate and describe home ranges total daily movements and the habitat conditions of Komodo Dragons. The research was carried out at the Wae Wuul Nature Reserve using the radio tracking method for 11 days, as most of the translocated Komodo Dragons could only survive in the short term. Results showed that translocated Komodo Dragons tend to stay near the initial release location. The average total daily movement translocated Komodo Dragons was 424.53 m day–1 with an average home range of 34.11 ha and an average core area of 8.20 ha. The habitats used by Komodo Dragons are savanna and monsoon forests dominated by bushes and trees. The presence of feral dogs and vehicle road access have the potential to pose a threat to the translocated Komodo Dragons. [ABSTRACT FROM AUTHOR]

Understanding a species' distribution is vital for making sound conservation and management decisions. Secretive behaviors and complicated seasonal movement patterns have made range delimitation surprisingly elusive for some North American birds, including the Northern Saw-whet Owl (Aegolius acadicus). Despite being among the most common of North American forest owls, only the species' breeding range is well demarcated. This has resulted in the species historically being considered a "northern" bird, with eastern migratory and nonbreeding ranges extending only as far south as central Missouri and eastern Tennessee. Recent banding efforts have shown that saw-whet owls are fall migrants much farther south. We extend this work by investigating stopover duration and nonbreeding habitat selection during 2 winters at the edge of the species' southern distribution in the Ozark Highlands of northwest Arkansas. We used radio telemetry to track 27 owls, with 17 individuals detected at least once post-release (n = 54 surveys and 131 total detections). Length of stay in the study area was most influenced by year—birds remained an average of 3.6 weeks longer during an irruption year—and our data suggest that the species uses the Ozark Highlands for both nonbreeding residency and brief stopover periods. During the 2 year study, 37% of marked owls were winter residents, 26% remained in the area temporarily, and 37% were not redetected. Winter habitat preferences of saw-whet owls in the southeast are consistent with what is known about the species in its more northernly range, with birds selecting conifers on south-facing slopes in areas with an open understory. Overall, our results suggest that saw-whet owls are not rare fall migrants and winter residents in Arkansas as was previously assumed, and more generally, are likely underappreciated winter predators in southern pine ecosystems. [ABSTRACT FROM AUTHOR]

There is little information on movement and foraging patterns of the Pilbara diamond-faced bat (Rhinonicteris aurantia), which is formally recognised as a major research priority for the species. An automated VHF radio telemetry system was used to track bat movement in the central Hamersley Ranges over 21 days during the dry season. Individuals were confirmed travelling an average of 4.88 km (±6.96) from their roost each night and a cumulative average distance of 7.02 km (±8.70). Notably, a female was recorded traveling ~40 km between two isolated ranges on two consecutive nights, demonstrating the long-range abilities of the species. Understanding movement patterns of threatened bats is critical, though sometimes difficult, to conserving their habitats. This study was undertaken to understand movement patterns for the threatened Pilbara diamond-faced bat, resulting in the recordings of two large, 40-km, flights undertaken over single nights. This study will be used to conserve habitat for the species and demonstrates the capability of new and emerging tracking technology. Photograph by Christopher Knuckey. [ABSTRACT FROM AUTHOR]

Abstract Background Automated radio telemetry (ART) systems enable high-temporal resolution data collection for species unsuited to satellite-based methods. A challenge of ART systems is estimating the location of radio tagged animals from the radio signals received on multiple antennas within an ART array. Localisation methods for ART systems with omni-directional receivers have undergone rapid development in recent years, with the inclusion of machine learning techniques. However, comparable machine learning methods for ART systems with directional antennas are unavailable, despite their potential for improved accuracy and greater versatility. To address this, we introduce an open-source machine learning-based location fingerprinting method for directional antenna-based ART systems. We compare this method to two alternative localisation approaches. Both alternatives use relative signal strengths recorded among multiple antennas to estimate the signal’s angle of arrival at each receiver. In the ‘biangulation’ approach, the location is estimated by finding the intersection of these angles from two receivers. In contrast, the ‘linear regression’ approach uses a linear regression model to estimate the distance from the receiver along the angle of arrival, providing a location estimate. We evaluate these methods using an ART data set collected for the southern black-throated finch (Poephila cincta cincta), in the Desert Uplands Bioregion of Queensland, Australia. Results The location fingerprinting method performed slightly better than the best performing alternative, the linear regression method, with mean positional errors of 308 m (SE = 17.7) and 335 m (SE = 18.5), respectively. The biangulation method performed substantially worse, with a mean positional error of 550 m (SE = 42.9, median = 540 m). Improved accuracy was observed with shorter distances between transmitters and receivers, higher signal strengths, and a greater number of detecting receivers, suggesting that increasing receiver density improves localisation accuracy, albeit with potential trade-offs in system coverage or cost. Furthermore, shorter pulse intervals of transmitters resulted in greater accuracy, highlighting the trade-offs among battery life, transmitter weight and radiative power. Conclusions The open-source location fingerprinting method offers an improved and versatile localisation approach suitable for a wide variety of ART system designs, addressing the challenge of developing study-specific localisation methods using alternative approaches.

Background: Automated radio telemetry (ART) systems enable high-temporal resolution data collection for species unsuited to satellite-based methods. A challenge of ART systems is estimating the location of radio tagged animals from the radio signals received on multiple antennas within an ART array. Localisation methods for ART systems with omni-directional receivers have undergone rapid development in recent years, with the inclusion of machine learning techniques. However, comparable machine learning methods for ART systems with directional antennas are unavailable, despite their potential for improved accuracy and greater versatility. To address this, we introduce an open-source machine learning-based location fingerprinting method for directional antenna-based ART systems. We compare this method to two alternative localisation approaches. Both alternatives use relative signal strengths recorded among multiple antennas to estimate the signal's angle of arrival at each receiver. In the 'biangulation' approach, the location is estimated by finding the intersection of these angles from two receivers. In contrast, the 'linear regression' approach uses a linear regression model to estimate the distance from the receiver along the angle of arrival, providing a location estimate. We evaluate these methods using an ART data set collected for the southern black-throated finch (Poephila cincta cincta), in the Desert Uplands Bioregion of Queensland, Australia. Results: The location fingerprinting method performed slightly better than the best performing alternative, the linear regression method, with mean positional errors of 308 m (SE = 17.7) and 335 m (SE = 18.5), respectively. The biangulation method performed substantially worse, with a mean positional error of 550 m (SE = 42.9, median = 540 m). Improved accuracy was observed with shorter distances between transmitters and receivers, higher signal strengths, and a greater number of detecting receivers, suggesting that increasing receiver density improves localisation accuracy, albeit with potential trade-offs in system coverage or cost. Furthermore, shorter pulse intervals of transmitters resulted in greater accuracy, highlighting the trade-offs among battery life, transmitter weight and radiative power. Conclusions: The open-source location fingerprinting method offers an improved and versatile localisation approach suitable for a wide variety of ART system designs, addressing the challenge of developing study-specific localisation methods using alternative approaches. [ABSTRACT FROM AUTHOR]

The mortality rate of long-distance migrants is known to peak in the period between fledging and completing the first year of life. Our understanding of this sensitive life stage, however, lags behind our understanding of determinants of nestling success (at least for temperate breeding birds). Here we collect diverse data (morphometrics, phenology, nest videos, radio tracking detections) on two generations of a long-distance migrant (the Purple Martin, Progne subis). We examine multiple life stages, to understand how in-nest conditions may carry over to the post-fledge period. Our data show that an earlier first-egg date is associated with higher parental quality as determined by their tracked movements and provisioning effort. Despite high variability in first-egg date, the duration of the nestling phase was approximately consistent between nests, with fledge-date and date of fledgling departure from the breeding grounds highly constrained by a relatively fixed duration of nestling development. Offspring of early-nesting parents fledged in better body condition, as evidenced by their larger wing chord measurements. Given the fixed nesting duration, this higher parental quality in early nesters led to early-season nestlings having the dual advantage of elevated body condition and early departure dates—two known predictors of first migration survival in this species and many others. Our work illustrates a potential carry-over effect from the nestling phase to fall-migration, and provides a useful example of linking diverse data sets across multiple life stages to extend our knowledge of breeding success to the less-understood post-breeding phase. [ABSTRACT FROM AUTHOR]

Radio techniques are widely used in wildlife tracking. Currently, the most common tracking methods include radio tracking (operating on Very high frequency (VHF) and Ultra high frequency (UHF)), satellite tracking (e.g., Argos satellite Doppler-based positioning system), and Global Navigation Satellite System (GNSS) tracking. One of the radio tracking systems is the Radio-Frequency Identification (RFID) system, characterized by small dimensions and a long operational period due to energy-efficient features. The advantages of RFID make it possible to apply this technique to track oak acorns in the process of zoochoric dispersal. In our study, we explored the potential applications of RFID systems for monitoring the dispersal of oak acorns. We developed a tracking system based on a semi-passive RFID tag, which we tested under laboratory and quasi-realistic conditions. The obtained results confirm the feasibility of using our system in radio tracking small objects such as oak acorns. [ABSTRACT FROM AUTHOR]

Radio tracking can be used to collect information about animal movement, home range, behaviour and habitat use. Many field studies have fitted radio transmitters to small rodents using permanent nylon cable tie collars and successfully collected movement and fate data. The approach to animal welfare within the context of scientific research prioritises minimising adverse effects on the research animals. Although a range of electronically activated release mechanisms exist in radio tracking collars for larger mammals, weight and size restrictions make these unsuitable for smaller animals (<30g). Our aim was to identify a radio transmitter model and attachment method of an appropriate size and weight that would remain attached to a house mouse (Mus musculus) for >20 days to collect movement data -- and then detach or show signs of detaching after 30 days. Laboratory and field trials identified that a cable tie collar with a cotton thread weak-link and customised radio transmitter was suitable for wild house mice in cropping paddocks. Glue-on methods did not stay attached for long enough to obtain more than a few days of tracking data. [ABSTRACT FROM AUTHOR]

GPS tracking collars were fitted to five free-ranging dogs (Canis familiaris) in the Arcadia Valley, Queensland to establish baseline movement data in this unique topographical landscape. Activity areas were generated with three home range methods using seasonally constrained fixes. Activity areas (Brownian Bridge and Utilisation Distribution) ranged from 2.9 to 689 km2 in this landscape, and revealed that topographical features previously thought to confine free-ranging dog movement were no barrier to habitat use. Free-ranging dogs were collared in the Arcadia valley Queensland to gain insight into how they use the unique topography. Anecdotal evidence suggests that topography like steep cliffs maybe a barrier to home range boundaries; dogs in this short study did not find cliffs a barrier. This information on dog activity helps inform managers on the use of habitat and helps to debunk perceptions around how dogs use the landscape. [ABSTRACT FROM AUTHOR]

The hazel dormouse is mainly an arboreal species with nocturnal habits that, in northern European countries, moves down to the ground to hibernate in the autumn where they stay until spring at locations not well understood. To prepare for hibernation, dormice accumulate fat reserves necessary to maintain vital bodily functions when food supply is lower and the energy cost of staying active exceeds the amount of energy that can be harvested in their habitat. Little is known about the hibernation ecology of hazel dormice or where they go in the winter. In this study, different methods to identify dormouse hibernacula were used: telemetry, systematic searches, and wildlife detection dogs. The movements of 31 individuals prior to and during hibernation were observed using radiotelemetry. Weight measurements of eight wild hazel dormice were recorded during the hibernation period and the rate of weight loss of each individual calculated as proportion of body mass per day. A total of 44 hazel dormouse hibernacula were identified: 24 by telemetry, 20 by systematic searches and none by wildlife detection dogs. Telemetry results indicated that dormice selected sites for their hibernaculum within 43m (SD=30) from the place where they were captured while active, suggesting that hibernation normally takes place within their home range. The timing of hibernation varied amongst individuals, with some dormice remaining active and feeding throughout the month of December. On average dormice lost 0.47% of their body mass per day during hibernation bouts. Despite dormice hibernating largely in leaf litter on the woodland floor, often at conspicuous locations, detecting hibernacula without the use of radiotelemetry proved labour intensive but possible through systematic searches. The fact that hazel dormice lose a relatively high proportion of their body mass during the winter highlights the challenges wild animals face to survive hibernation. [ABSTRACT FROM AUTHOR]

Very high frequency (VHF) radio tracking technology deployed on terrestrial vertebrates has been well utilized in ecology without much evolution since the 1960s. With the advent of multi‐species rewilding projects, and the new field of reintroduction biology, there has been an increase in requirements for telemetry systems to monitor survival and mortality for many animals simultaneously. Common, pulsed VHF can only monitor one individual on each radio frequency, and the number of individuals monitored is constrained by the amount of time spent on each frequency to facilitate a detection and the number of receivers. Coded VHF largely removes these constraints by using a digital code that can simultaneously monitor up to 512 individuals on a single frequency. Incorporated into an autonomous monitoring system, the coded VHF system also greatly reduces time in the field to confirm the status of individuals. Here we demonstrate the utility of coded VHF technologies applied to monitoring a reintroduced population of brush‐tailed bettong (Bettongia penicillata) on the Southern Yorke Peninsula in southern Australia. A system of autonomous monitoring towers was able to monitor 28 different individuals simultaneously without having to change frequency on any of the towers. During a single 24‐h period, one individual was recorded 24,078 times. Key benefits of the high detection rate and autonomous recording are, a timely response to mortalities or a predation event, the detection of nocturnal, cryptic, or burrowing species whenever they are active, and the reduced need for personnel to be in the field. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aims to investigate the behavior and ecology of nutria (Myocastor coypus), a semi-aquatic rodent that was introduced to South Korea for commercial farming and subsequently damaged aquatic ecosystems after its release. How the behavioral ecology of introduced nutria changes over time and across seasons remains unclear. Twenty-four adult nutria (twelve males and twelve females) were radio tracked in 2015–2016 to identify their home range size and activity patterns in the Macdo wetland, South Korea. This study found that the nutria home range size varied seasonally, with males having larger home ranges than females. Additionally, nutria showed crepuscular and nocturnal activity patterns throughout the year, with no significant difference between sexes. The findings of this study provide crucial information on the home range and activity patterns of introduced nutria in the Macdo wetland, which can guide management efforts to mitigate their impacts on the ecosystem. It is the first quantitative analysis of the home range and activity patterns of introduced nutria based on radio tracking data in the Macdo wetland. Nutria (Myocastor coypus) are semi-aquatic rodents that were introduced in South Korea for commercial farming but significantly damaged aquatic ecosystems. Understanding nutria ecological behavior is essential for developing effective control and eradication strategies to mitigate their impacts. Thus, this study aimed to investigate the home range and activity patterns of 24 nutria (12 males and 12 females) in the Macdo wetland in South Korea from 2015–2016 through radio tracking. The average minimum convex polygon home range of the nutria was 0.29 ± 0.55 km2, with a 95% kernel density estimation (KDE) home range of 0.43 ± 0.85 km2 and a 50% KDE home range of 0.05 ± 1.1 km2. The home range of males was larger than that of females; however, the winter home range of females was as large as that of males. The home range also varied seasonally, with the smallest observed in winter. The nutria showed crepuscular and nocturnal activity patterns throughout the year, with no significant difference between sexes. The activities in spring, summer, and autumn showed no significant differences, but the activity in winter was significantly different from that in the other seasons. This study may serve as a basis for developing appropriately timed and scaled management strategies to mitigate the impacts of nutria on ecosystems. In conclusion, several environmental and biological factors contribute to the behavior of nutria in South Korea. [ABSTRACT FROM AUTHOR]

Wildlife tracking is used to acquire information on the movement, behaviour and survival of animals in their natural habitat for a wide range of ecological questions. However, tracking and monitoring free-ranging animals in the field is typically labour-intensive and particularly difficult in species that are small, cryptic, or hard to re-capture. In this paper, we describe and evaluate an Internet-of-Things (IoT)-based tracking system which automatically logs detected passive RFID tags and uploads them to the cloud. This system was successfully evaluated with 90 sensor modules deployed in a 30 ha wildlife sanctuary to monitor a small nocturnal mammal of less than 20 g in body size.

Dense ground cover and understory can be important as diurnal shelter for terrestrial mammals. Fire can lead to the short-term removal of much of this shelter. Here, we report on the shelter site selection of the Southern Brown Bandicoot Isoodon obesulus obesulus and Long-nosed Bandicoot Perameles nasuta eight months after a wildfire. We analysed the number of shelters, frequency of shelter use, nest size, and shelter site microhabitat. Southern Brown Bandicoots used significantly more shelters than Long-nosed Bandicoots. Both species preferred to use shelters with significantly lower levels of transmitted light than matched control areas. Within the burnt landscape, Southern Brown Bandicoots located their refuges under regrowth eucalypts, whereas Long-nosed Bandicoots showed no preference for any microhabitat. Southern Brown Bandicoots built nests significantly higher above ground than Long-nosed Bandicoots. Nests built in more dense and darker microhabitats were significantly taller than those built in more open habitats. Following fire, the Southern Brown Bandicoot required a more dense groundcover to conceal its taller nests and was able to take advantage of regenerating mallee eucalypts for shelter. Land managers need to be aware that hazard reduction burning in coastal woodland and heath will temporarily deprive Southern Brown Bandicoots of diurnal shelter sites and should, therefore, where practicable, retain patches of unburnt dense undergrowth to ensure a mosaic of different aged habitat and habitat structure. [ABSTRACT FROM AUTHOR]

The Short-eared Owl (Asioflammeus) inhabits open grasslands and belongs to the ground-breeding birds that have experienced the most severe declines during recent decades. Here, we studied nest and fledgling survival of the owl species in relation to (i) habitat composition, (ii) vegetation structure, (iii) weather conditions and (iv) vole abundance. The study was conducted on the East Frisian Island of Spiekeroog (southern North Sea, Lower Saxony, Germany), which harbours one of the last remaining permanent populations of the species in Central Europe. With a mean hatching success of 5.6 young per nest (N = 34) and an average probability of nest survival of 0.9 (N = 28), values ascertained in this study exceeded those reported in previous research. We attribute this to the special environmental conditions on the island, i.e. (i) the absence of mammalian mesopredators such as the Red Fox (Vulpesvulpes), (ii) nearly no disturbance through agricultural measures and (iii) low level of human disturbance due to legal regulations of the National Park. By contrast, the survival of fledglings was lower than survival of nests and varied considerably between the investigated years. Weather conditions were the key driver of fledgling survival. Maximum wind speed and sunshine duration had a negative effect on the probability that chicks successfully fledged. Both lead to reduced hunting success, and the former is also associated with increased costs for thermoregulation. Consequently, increasing frequency of extreme weather events caused by climate change could negatively impact the breeding success of vole-dependent raptors, such as the Short-eared Owl. [ABSTRACT FROM AUTHOR]

Wildlife tracking is used to acquire information on the movement, behaviour and survival of animals in their natural habitat for a wide range of ecological questions. However, tracking and monitoring free-ranging animals in the field is typically labour-intensive and particularly difficult in species that are small, cryptic, or hard to re-capture. In this paper, we describe and evaluate an Internet-of-Things (IoT)-based tracking system which automatically logs detected passive RFID tags and uploads them to the cloud. This system was successfully evaluated with 90 sensor modules deployed in a 30 ha wildlife sanctuary to monitor a small nocturnal mammal of less than 20 g in body size. [ABSTRACT FROM AUTHOR]

Semipalmated sandpipers are Arctic breeding shorebirds that migrate to South America during the non‐breeding season. Little work has been done to understand the daily movements, foraging habits and metabolic state of this species on stationary nonbreeding grounds. Our work was conducted at the Banco dos Cajuais Western Hemisphere Shorebird Reserve Network (WHSRN) site in Northeast Brazil. We captured semipalmated sandpipers in February and March 2019 and 2020 and attached nanotags to monitor their daily movements. Blood samples were taken to measure plasma triglycerides (an index of fattening rate). We also conducted behavioral observations on foraging birds. Using tracking data we determined that most semipalmated sandpipers appeared to use sunrise/sunset as an indicator for movement between salina and tidal flat habitats, and a smaller portion used tidal height. We found birds spent similar amounts of time foraging on tidal flats and in salinas, though different foraging modes were used. Plasma triglyceride measures suggest semipalmated sandpipers had not started preparing to migrate when sampled. We successfully tracked semipalmated sandpipers to North America during northward migration in 2020, detecting eight within the United States. Tracking results suggest many stopped elsewhere in South America to fuel for migration, though some may have fueled at the Banco dos Cajuais. By demonstrating substantial use of both natural and altered habitats in the region by migrant semipalmated sandpipers, these data highlight the need for broader conservation measures throughout coastal regions of South America. [ABSTRACT FROM AUTHOR]

Radio Doppler measurements between the InSight lander and NASA's Deep Space Network have been acquired for measuring the rotation of Mars. Unlike previous landers used for this purpose that utilized steerable high-gain antennas, InSight uses two fixed medium-gain antennas, which results in a lower radio signal-to-noise ratio (SNR). Lower SNR results in additional thermal noise for Doppler measurements using standard processes. Through a combination of phase averaging and traditional data compression, the increased thermal noise due to low SNR can be removed for most of the signal of interest, resulting in more accurate Doppler measurements. During the first 900 days of InSight operations, Doppler measurements were improved by ~25% on average using this method. [ABSTRACT FROM AUTHOR]

In the context of conservation science and management, the Judas technique refers to outfitting an animal (a Judas animal) with a radio transmitter or other identifier so that its movements can be tracked to locate conspecifics. Although this term is commonly used, some consider it offensive due to historical associations of the word Judas with anti‐Semitic sentiments. Thus, the term has a negative sentiment polarity (i.e., the assertion that words can have positive, negative, or neutral connotations). We investigated the etymology of the Judas term in peer‐reviewed scientific literature to outline its contextual introduction and use. Prior to the term being co‐opted by conservation scientists Judas [animal] was a common term in the livestock industry to describe animals used to lead herds to slaughter. Subsequently, the term has been published and promulgated through conservation‐related research and the literature. Due to a negative sentiment polarity linked to this term, especially among members of the public, alternative nomenclature may be preferred to increase objective and dispassionate scientific communication. [ABSTRACT FROM AUTHOR]

Abstract Aim To investigate the ecological relationship between breeding and wintering in specialist and generalist long‐distance migratory species, and the links between densities and range sizes. Location Denmark, Senegal and Ghana. Methods We use radio tracking to study spatial behavior and habitat use in three morphologically and ecologically similar and closely related Phylloscopus species on their widely separated breeding and wintering distributions. During wintering and breeding, willow warblers P. trochilus (winter: n = 9, breeding: n = 13), chiffchaffs P. collybita (n = 11, n = 7), and wood warblers P. sibilatrix (n = 17, n = 14) were tracked. Results Willow warblers P. trochilus increased home range sizes in winter, whereas it was similar in chiffchaffs P. collybita and wood warblers P. sibilatrix, in both seasons. Home ranges overlapped more in winter than in the breeding season. In winter, home range overlap was similar among species but larger overlap during breeding was indicated for willow warblers. Tree cover was unrelated to home range size but significantly higher in breeding than in winter in all species. However, whereas willow warblers and wood warblers maintained some degree of tall tree cover inside their home ranges in winter, chiffchaffs changed from more than 80% to

Abstract Detecting the arbitrary movements of fast-moving insects under field conditions is notoriously difficult because existing technologies are limited by issues of size, weight, range and cost. Here, we establish proof-of-concept for a prototype long-range, passive radio frequency identification (RFID) tagging system for detecting bumblebees and similar sized insects. The prototype tags, weighing 81 mg (49% of mean bee body weight), were flown by bumblebees in a glasshouse and detected at a distance of 1.5 m from a 2 W UHF reader with two aerials. This detection distance is two orders of magnitude greater than existing RFID tags that can be flown by medium-sized bees and, thus, is a significant breakthrough for insect tracking that could be applied to plant conservation and restoration efforts in fragmented landscapes. Proof-of-concept has been successfully established and, with further development, we are likely to optimize the system by reducing tag size and weight to limit effects on bee behaviour, and by increasing the detection distance. We envisage the production system being used to detect and track bee movement pathways within a designed network of field-deployed low-cost readers and aerials. The production system could be used in a wide variety of scientific and commercial applications.

In migratory birds, constraints due to breeding are relaxed during the non-breeding season and thus, social behaviours and spatial associations are potentially more directly coupled to food resources and habitats. Use of space and territorial behaviour has rarely been studied in Afro-Palearctic migrants. Variation in strategies could exist among species within the same habitat because of differences in foraging, diet and microhabitat. We compare use of space and association with conspecifics in Common Chiffchaffs Phylloscopus collybita and Subalpine Warblers Sylvia cantillans at a non-breeding site in northern Senegal using radio telemetry and playback experiments. Home ranges of Chiffchaffs were larger and overlapped more than those of Subalpine Warblers. Though Chiffchaffs were often close together, we found no signs of spatial association among individuals in either species. Chiffchaffs showed no clear pattern of territorial response to conspecific song; whereas, playback elicited a territorial response in most Subalpine Warblers. Our results suggest species-specific differences in use of space that might reflect differences in foraging ecology and microhabitat. [ABSTRACT FROM AUTHOR]

A detailed understanding of the spatial ecology and habitat requirements of endangered species is critical for population restoration and conservation. Home ranges and movements of the endangered Chinese softshell turtle (Pelodiscus sinensis) were investigated in the Yellow River, northwestern China, from October 2016 to July 2018. We monitored 9 adult turtles (5 females and 4 males) with radio transmitters. Mean linear range size was 440 ± 161 m SD, mean river channel area was 1.98 ± 0.72 ha SD, the average minimum convex polygon was 1.36 ± 0.65 ha SD, average 95% kernel density estimator measured 0.84 ± 0.51 ha SD, with a core area (50% kernel density estimator) of 0.30 ± 0.20 ha SD. Home range values were not significantly different between the sexes nor were they related to straight-line carapace length or mass. Daily movements of P. sinensis averaged 35 ± 18 m SD for males and 43 ± 18 m SD for females, and there was no significant difference between sexes or significant correlation between movement patterns and body size. However, during the nesting season, there was a significant difference between sexes. Turtle activity was highest in May (average daily movement 59 ± 6 m SD) and lowest in January (0.4 ± 0.6 m SD). Given that P. sinensis individuals have small home ranges and are capable of existing in small rivers, management efforts should protect smaller rivers that may be easily overlooked. Results from this study provide the first assessment of home range requirements for P. sinensis, which may be used in future population modeling efforts and are important for establishing conservation strategies for this vulnerable species. [ABSTRACT FROM AUTHOR]

From 2000 to 2002, the reproductive ecology of the endangered Hainan four eye-spotted turtle (Sacalia insulensis) was studied on Hainan Island, China. A total of 147 adult females were captured, and their reproductive status was evaluated by palpation, X-ray imaging, and ultrasound. Twenty-two gravid females were under observation when they laid their eggs. We observed gravid females and nesting behavior along stream banks between December and April. Nest dimensions ranged from 5 to 6 cm in diameter and from 2 to 3 cm in depth. No females in our study produced more than 1 clutch per season. Clutch size average was 1.9 eggs (range = 1–3 eggs, SD = 0.56, n = 22) with an average egg mass of 16.05 g (range = 11.8–21.0 g, SD = 2.417, n = 21), an average egg width of 2.36 cm (range = 2.1–2.7 cm, SD = 0.135, n = 21), and an average length of 4.65 cm (range = 3.9–5.3 cm, SD = 0.400, n = 21). Hatching success rate was 53%, and hatchlings emerged after an average of 120.9 d (range = 98–148 d, SD = 14.94, n = 21) in late June to early July. The mean nesting site ground temperature was 24.43°C (range = 15.0°C–30.2°C, SD = 2.712, n = 7). [ABSTRACT FROM AUTHOR]

Arapaima (Arapaima sp.) are highly overexploited fish endemic to the Amazon basin. Because the fish are obligate air‐breathers, it is possible to use surface‐breathing events to count individuals visually for population censuses important for conservation, yet uncertainties remain about body size and environmental influences on air‐breathing intervals, and thus count accuracy.This study examined relationships between breathing intervals and environmental parameters (e.g. water temperature and transparency) and body size for radio‐tagged arapaima (n = 12) in an upland river‐floodplain (Lake Ayapuá, Amazonas, Brazil). Generalized additive mixed models were used to evaluate environmental, size, and behavioural correlates of breathing intervals.Temperature was the most influential predictor of air‐breathing intervals, followed by body size. The shortest breathing intervals were associated with consecutive 'aggressive' breaths while the longest breathing intervals had consecutive 'calm' breaths. Type of breath, size, and temperature predictors revealed that breathing intervals ranged from 4 to 46 min and were not significantly different among life stages (x¯ = 15.9 min for sub‐adults and adults (>1 m); x¯ = 14.8 min for juveniles (<1 m)).Whereas the current population census method uses fish counts in 20‐min intervals, this study found that 15% of observed breaths, and two thirds of fish, took longer than 20 min to breathe. These findings were obtained in relatively cool‐water environments, so it is recommended that future population census methods consider water temperature (e.g. extend intervals used for counts in cooler waters), which may improve the accuracy of census counts and thus further enhance arapaima conservation efforts.This study demonstrated an effective method in which fundamental biological information is used to inform and improve population census methods for an imperilled fish in a region where traditional stock assessment is ineffective. Similar approaches for adaptive stock assessments could be applied to improve conservation of other air‐breathing fishes (e.g. lungfishes) globally. [ABSTRACT FROM AUTHOR]

Although radio collars are widely applied in movement ecology, their use in animals with changing neck circumferences is challenging. We are proposing a model of a simple, cheap, and expandable collar that is suitable for the monitoring of young terrestrial mammals. We tested the collar on young crab-eating foxes. There was no register of injuries caused by the collar to the tagged animals, and they functioned appropriately. Thus, we hope this note will encourage further researchers to use our method to monitor the movement patterns of young animals, not only for canids but also for other species of terrestrial mammals. [ABSTRACT FROM AUTHOR]

Loss of foraging habitat and reductions in insect prey are key factors responsible for declines in bat populations. Identifying important bat foraging habitats and the ecological requirements and conservation status of prey provides evidence for appropriately targeted conservation management strategies. We examined the foraging habits of the barbastelle, Barbastella barbastellus, at the northern edge of its European range using a combination of radio tracking, to determine home range use and habitat selection, and DNA metabarcoding, to identify prey items consumed. Riparian vegetation and broadleaved woodland were the habitat types most strongly selected by foraging bats. Hedgerows within pastoral habitats were also important foraging features within the landscape. We identified 120 different prey items within faecal pellets, the majority of which were moths (97.5%). The large majority (97%) of prey items consumed have larval stages dependent on host plants that are typically found within habitats selected by foraging B. barbastellus. Almost half of all moth prey species identified have undergone considerable population declines in recent decades. We present the most comprehensive list to date of prey consumed by B. barbastellus and provide evidence that conservation management policies should target the protection and enhancement of key B. barbastellus foraging habitats within a 6.5 km sustenance zone around maternity roost sites. Riparian habitat, broadleaved woodland and linear landscape features such as hedgerows should be managed to improve their value to foraging B. barbastellus as well as the developmental stages of their preferred moth prey. [ABSTRACT FROM AUTHOR]

Urban areas are increasing globally causing fragmentation and loss of habitats for many forest dwelling species. At the same time new habitats are created, which may be exploited by species with a broad ecological tolerance. Bats form the largest mammal group living in cities in Central Europe. Species diversity might be higher in some cities compared to rural areas. Yet, habitat-specialists struggle with rapid landscape change and urban development. The Bechstein's bat Myotis bechsteinii is dependent on old growth deciduous forests that supply tree cavities to roost in. The use of small home ranges requires high prey abundance around roosts. Despite their habitat specialization we identified two Bechstein's maternity colonies within the metropolitan area of Frankfurt/Main (Germany). The colonies numbered 25 and 31 adult females respectively. We radio tracked individuals from both colonies (n = 14) and compared their habitat use to that of females (n = 79) of 11 colonies from rural woodlands. We identified a total of 29 roosts used by the two maternity colonies during summer. Roost choice of the urban forest colonies was similar to the rural forest colonies with a preference for oak trees with woodpecker holes. The distances between roosts were similar between urban and rural colonies. Habitat selection was strongly towards old forest patches. We emphasize the importance of the persistence of old forest islands within urban areas to support remaining bat colonies with a network of bat areas, similar to the important bird areas (IBAs). Specialized species that fail to adapt to the rapid changes may survive within the urban environment relying on old forest patches. [ABSTRACT FROM AUTHOR]

As part of a project to introduce avian predators for biological pest control, we used hard and soft release methods to introduce Barn Owls (Tyto alba) in the urban area of Universiti Sains Malaysia in Penang, Malaysia. We tested five methods: (1) hard release of non-acclimated adults, (2) hard release of non-acclimated juveniles, (3) soft release of hand-reared fledglings, (4) soft release of acclimated juveniles, and (5) soft release of acclimated adults. We employed radio-tracking to analyze the success of all methods, and the movement and survival of some of the released birds. We analyzed regurgitated pellets to study the diet of the successfully introduced owls. All hard-released non-acclimated adults and non-acclimated juveniles left the study area within a few days after their release. Soft release of hand-reared fledglings was also unsuccessful, as we could only detect the radio-tracked owls for ≤10 d after their release. Of the nine acclimated juveniles that were soft released, one stayed within the study area for 25 d but eventually dispersed. The soft release using acclimated adults was the most successful release method, as 60% (3 of 5 birds) of the released owls were tracked for >30 d and became established as resident birds in the study area. We observed these adults roosting and hunting prey within the study area. Analysis of regurgitated pellets showed the resident Barn Owls preyed primarily on small mammals. Our results suggest that the most suitable method to introduce and establish Barn Owl populations in an urban area was by using soft release of acclimated adults. [ABSTRACT FROM AUTHOR]

Amphibians are among the most threatened vertebrate taxa due to anthropogenic habitat change and emerging pathogens. The fungus Batrachochytrium dendrobatidis (Bd) may cause trade‐offs between the immune responses and other important functions, such as mobility. The pool frog (Pelophylax lessonae) is red‐listed in Sweden, and an earlier study conducted in our study area did not detect the fungus. In this study, 67 Swedish pool frogs were tested for Bd. Of these, 28 adults were provided with external radio transmitters and tracked during the summer and autumn to compare movement among infected and non‐infected individuals. Additionally, we tested some individuals for Bd twice during the summer to study intra‐seasonal variation in individual infections. Our results suggest that Bd has recently invaded these pool frog populations. During autumn, movement distances of infected pool frogs were shorter compared to uninfected individuals, and summer movements within ponds were reduced by increasing Bd load. We also found that the frogs can clear (or reduce) Bd infection during their active season. The results from this study increase understanding of the implications of Bd infections in an anuran fringe population, as well as in amphibian metapopulations, and can further guide amphibian conservation planning and management. [ABSTRACT FROM AUTHOR]

African tigerfish Hydrocynus vittatus (n = 35) were tagged with external radio‐transmitters in the Kavango River, Namibia, to determine whether freshwater protected areas could be an effective tool for the management and conservation of this species. They were manually tracked in the core study area of 33 km every c. 12 days from July–October 2016 to May 2017 for between 123 to 246 days. In addition, 14 extended surveys were carried out for up to 680 km to determine the total area use of the tagged individuals. Tigerfish displayed at least two behavioural patterns either having high site fidelity with shorter movements or using larger areas with longer movements. Twenty‐three (66%) of the tigerfish had high site fidelity using an area of less than 33 km of river, whereas 12 tigerfish (34%) undertook long distance movements of up to 397 km upstream and 116 km downstream from their tagging locations. During the long‐distance movements tigerfish crossed the territorial boundaries of Angola, Namibia and Botswana. Of the 35 fish that were monitored, 14 (40%) spent more than 80% of the monitored time in the 33 km study area and 18 (51%) stayed within the study area for at least 50% of the monitored time. These findings suggest that freshwater protected areas may be a useful management tool and we predict that a protected river area of 2–5 km river length could protect 25.9–34.6% of the population for at least 75% of the time whereas protection of 10 km river length could protect at least 50% of tigerfish for at least 75% of the time. [ABSTRACT FROM AUTHOR]

The Pennsylvania Department of Transportation is currently performing bog turtle radio-tracking and environmental compliance monitoring as required by the U.S. Army Corps of Engineers 404 permit and U.S. Fish and Wildlife Service biological opinion. Radio tracking of bog turtles was initiated in 1999 and will continue to one year post-construction, anticipated to be in 2006. The biological opinion for the project required the department to minimize direct and indirect impacts to bog turtles and critical habitat through innovative highway engineering design modifi cations, specialized containment fencing, and seasonal constraints for certain construction activities. Pre-construction provisions in compliance with the biological opinion include vegetation community mapping; ground water monitoring; invasive species management and monitoring; and bog turtle behavior and movement patterns. The research has confi rmed many of the natural history characteristics of the species cited in previous studies in the scientifi c literature. However, behavior and movement patterns previously undocumented have been recorded. Telemetry data from this transportation project continues to expand our understanding of this federally threatened species. Monitoring throughout construction of the project will confi rm if the implemented engineering design modifi cations have avoided and minimized potential impacts to the species metapopulation. This project is an example of a transportation undertaking that is designed and constructed in such a manner as to fulfi ll the project purpose and promote the conservation of a threatened species.

Mammalian space‐use patterns are largely determined by the resources utilized as well as by given habitat characteristics, as can be illustrated by rodents displaying predominantly subterranean activity. These rodents are largely limited in their use of space by their burrow systems. This results in smaller home ranges than is usual for rodents of a similar size. However, there is little information regarding how stable these home ranges are over time. We studied space use in the giant root‐rat, Tachyoryctes macrocephalus, a large fossorial rodent endemic to the Bale Mountains of southern Ethiopia where it is the principal prey of the Ethiopian wolf Canis simensis. We radio‐tracked 22 root‐rats during a period of 36 days in the early dry season and 17 of them once again during a period of 37 days in the late dry season. The root‐rats occupied very small (around 100 m2) home ranges which were often tightly packed, especially on a wetland shore that was a part of the study locality, but displayed little overlap. Almost 30% of the radio‐collared root‐rats of either sex dispersed (80–428 m from their original home range) during the 5 months of the study, mostly in a period between the early and late dry season characterized by a decreasing food supply and the soil becoming dry and hard. Individuals who did not disperse during this time usually shifted their home range. Root‐rats living on the wetland shore, which were the largest and therefore likely competitively strongest individuals, shifted their home ranges into the wetland, likely for the purpose of increasing their food supply. [ABSTRACT FROM AUTHOR]

At present, tracking data for planetary missions largely consists of radio observables: range-rate (Doppler), range and angular position (VLBI/ Δ DOR). Future planetary missions may use Interplanetary Laser Ranging (ILR) as a tracking observable. Two-way ILR will provide range data that are about 2 orders of magnitude more accurate than radio-based range data. ILR does not produce Doppler data, however. In this article, we compare the relative strength of radio Doppler and laser range data for the retrieval of parameters of interest in planetary missions, to clarify and quantify the science case of ILR, with a focus on geodetic observables. We first provide an overview of the near-term attainable quality of ILR, in terms of both the realization of the observable and the models used to process the measurements. Subsequently, we analyse the sensitivity of radio Doppler and laser range measurements in representative mission scenarios for parameters of interest. We use both an analytical approximation and numerical analyses of the relative sensitivity of ILR and radio Doppler observables for more general cases. We show that mm-precise range normal points are feasible for ILR, but mm-level accuracy and stability in the full analysis chain are unlikely to be attained, due to a combination of instrumental and model errors. We find that ILR has the potential for superior performance in observing signatures in the data with a characteristic period of greater than 0.33–1.65 hours (assuming 2–10 mm uncertainty for range and 10 μ m/s at 60 s for Doppler). This indicates that Doppler tracking will typically remain the method of choice for gravity field determination and spacecraft orbit determination in planetary missions. ILR data will be able to supplement the orbiter tracking data used for the estimation of parameters with a once-per-orbit signal. Laser ranging data, however, are shown to have a significant advantage for the retrieval of rotational and tidal characteristics from landers. Similarly, laser ranging data will be superior for the construction of planetary ephemerides and the improvement of solar system tests of gravitation, both for orbiter and for lander missions. [ABSTRACT FROM AUTHOR]

We used externally applied transmitters to study movements of female grass snakes (Natrix natrix) during the egg-laying period in a near-urban landscape in Sweden. Half of the studied snakes were residents while the other half were translocated individuals with no previous experience of the area. As predicted, resident females moved more goal-oriented and shorter distances than did translocated individuals. Habitat use did not differ between resident and translocated snakes; they were typically found in bushes, reeds, and tall vegetation. Habitat preference (use in relation to availability) showed that bushy habitats, tall grassy vegetation and reedbeds were over-used in proportion to availability, whereas forest and open grass lawns were used less than expected based on availability. Our study highlights the importance of preserving and restoring linear habitat components providing shelter and connectivity in conservation of grass snakes. We suggest that externally applied transmitters are a better option than surgically implanted ones in movement studies of grass snakes, and that translocation as a conservation method for snakes has drawbacks. [ABSTRACT FROM AUTHOR]

Birdwing butterflies are a monophyletic group of swallowtail butterflies (Papilionidae) protected by national and international laws and often serve as flagships of insect conservation. Selecting the Golden Birdwing (Troides aeacus) as an example, we demonstrate an effective way to simultaneously record the activity of multiple birdwing butterflies using radio telemetry in hard-to-access mountainous terrain. During the summer flight period of T. aeacus (June and July), a single researcher was able to obtain 30-min records of movement patterns for ten individuals for an average of 4 days by fastening 0.22 g transmitters onto the butterflies, in the mountainous valleys of Mt. Gongga, China. The maximum distance the butterflies traveled over the 4 day period was 4314 m away from the starting location. During this time, the average dispersal rate was 38.07 m/h (n = 9, sd = 85.11); average movement speed was 293.48 m/h (n = 9, sd = 121.45). Flight patterns of butterflies collected from low and high elevation habitats showed no significant differences. Activity levels of individuals from both low and high elevation habitats track diurnal fluctuation in temperature. Flight activity is positively correlated with temperature and negatively correlated with humidity. Our data provide basic parameters of real-time flight activity and dispersal ability for a species of conservation importance. The methodology is highly suitable for monitoring endangered lepidopteran species in otherwise difficult-to-access terrain. [ABSTRACT FROM AUTHOR]

A linear state‐space model is described whose second‐order moments match that of a hidden Markov chain (HMC). This model enables a modified transition probability matrix to be employed within minimum‐variance filters and smoothers. However, the ensuing filter/smoother designs can exhibit suboptimal performance because a previously reported transition‐probability‐matrix modification is conservative, and identified models can lack observability and reachability. This article describes a less‐conservative transition‐probability‐matrix modification and a model‐order‐reduction procedure to enforce observability and reachability. An optimal minimum‐variance predictor, filter, and smoother are derived to recover the Markov chain states from noisy measurements. The predictor is asymptotically stable provided that the problem assumptions are correct. It is shown that collapsing the model improves state‐prediction performance. The filter and smoother recover the Markov states exactly when the measurement noise is negligible. A mining vehicle position tracking application is discussed in which performance benefits are demonstrated. [ABSTRACT FROM AUTHOR]

Adult Podocnemis unifilis were monitored using VHF radio tracking from September 2013 to September 2014 in the Rio Trombetas Biological Reserve, Pará, Brazil. Our aim was to analyze the use of space by this species near the nesting beach base by describing size and overlap of estimated home ranges. Transmitters were attached to 10 males and 10 females. The mean home range size calculated through the fixed-kernel (FK) method with 95% of the fixes was 79.28 ± 77.08 ha (0.56–215.07 ha; n = 13). The mean of overlapping areas was 14% with FK95% (0.02%–81%; n = 13) and 5% with FK50% (0.1%–23%; n = 9). There was a significant difference in the mean overlapping areas between females and males. The analysis of the overlap of activity centers estimated by FK50% is extremely important for the establishment of conservation strategies in the management plan for this species in the reserve. We were able to identify 2 critical areas for the maintenance of this population where there was a frequent overlap of activity centers: the first, identified during the dry season, was composed of small overlaps among 7 turtles and was near the nesting areas on the clay banks within the Lago Jacaré; the second, identified during the rainy season, was composed of a concentration of overlap areas of larger size among 6 turtles and was an open area in the flooded forest. It is important not only to protect the nesting areas during the dry season but also to protect flooded forest areas with the major intensity of use along with the canals that link the flooded forests to the lakes in the rainy season. For conservation purposes, it is necessary to continue the protection of the nesting beaches throughout the savannas inside the lake where the species nests in the dry season. The flooded forest areas that are zones of intense use during the rainy season, and the canals where the turtles can move between lakes must be protected throughout the year. [ABSTRACT FROM AUTHOR]

Aim: To investigate the ecological relationship between breeding and wintering in specialist and generalist long‐distance migratory species, and the links between densities and range sizes. Location: Denmark, Senegal and Ghana. Methods: We use radio tracking to study spatial behavior and habitat use in three morphologically and ecologically similar and closely related Phylloscopus species on their widely separated breeding and wintering distributions. During wintering and breeding, willow warblers P. trochilus (winter: n = 9, breeding: n = 13), chiffchaffs P. collybita (n = 11, n = 7), and wood warblers P. sibilatrix (n = 17, n = 14) were tracked. Results: Willow warblers P. trochilus increased home range sizes in winter, whereas it was similar in chiffchaffs P. collybita and wood warblers P. sibilatrix, in both seasons. Home ranges overlapped more in winter than in the breeding season. In winter, home range overlap was similar among species but larger overlap during breeding was indicated for willow warblers. Tree cover was unrelated to home range size but significantly higher in breeding than in winter in all species. However, whereas willow warblers and wood warblers maintained some degree of tall tree cover inside their home ranges in winter, chiffchaffs changed from more than 80% to <1% tree cover, indicating a niche shift. Main conclusions: Individuals of all three species showed changes between breeding and wintering areas in spatial behavior and habitat availability, with larger overlap in winter. The differences in patterns were potentially related to being generalist (willow warbler) or specialist (chiffchaff and wood warbler). These ecological relationships are important for the conservation of migrants and for understanding the link between breeding and wintering distributions and ecology. [ABSTRACT FROM AUTHOR]

Geodetic analysis of radio tracking measurements of the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft while in orbit about Mercury has yielded new estimates for the planet's gravity field, tidal Love number, and pole coordinates. The derived right ascension (α = 281.0082° ± 0.0009°; all uncertainties are 3 standard deviations) and declination (δ = 61.4164° ± 0.0003°) of the spin pole place Mercury in the Cassini state. Confirmation of the equilibrium state with an estimated mean (whole planet) obliquity ϵ of 1.968 ± 0.027 arcmin enables the confident determination of the planet's normalized polar moment of inertia (0.333 ± 0.005), which indicates a high degree of internal differentiation. Internal structure models generated by a Markov Chain Monte Carlo process and consistent with the geodetic constraints possess a solid inner core with a radius (ric) between 0.3 and 0.7 that of the outer core (roc). Key Points: New solution for Mercury's gravity field provides crucial information on the planet's tidal response and orientationNew determination of Mercury's pole position fully satisfies the equilibrium Cassini stateNew estimate of Mercury's polar moment of inertia supports the presence of a large solid inner core [ABSTRACT FROM AUTHOR]