Capture Site Research Articles

Attitudes towards causes of and solutions to conflict between humans and Asian elephants

AbstractMany Asian elephant populations inhabit fragmented human‐dominated landscapes. Human–elephant conflict (HEC) has intensified in such regions, resulting in the deaths of hundreds of people and elephants each year. Controversy between stakeholders then arises as people debate the merits of HEC mitigation approaches, stifling progress. We conducted a survey to evaluate the opinions of experts, farmers and others who have and have not experienced HEC (n = 611), on the causes of HEC, the importance of, conservation of and co‐existence with elephants, and on the acceptability and effectiveness of potential HEC mitigation methods. Analysis of variance and the Potential for Conflict Index showed that all groups agreed with nine of the 10 causes of HEC assessed, on average. All respondent groups had mostly positive attitudes towards the importance and conservation of elephants. However, farmers exposed to HEC disagreed that people should co‐exist with elephants and supported the view that elephants should be removed from human habitats. All groups agreed on the acceptability and effectiveness of electric fencing, early warning systems with infrasonic call detectors, Global Positioning System collars and geophones. However, there was disparity in views between the experts and other stakeholder groups on the acceptability and effectiveness of restricting elephants to protected areas, and translocation of problem elephants to protected areas away from their capture site or to wild elephant holding grounds. While similar views between stakeholders on many subjects are encouraging for elephant conservation, the disparities identified should be given greater attention when planning HEC management programs to minimize conflict between stakeholders.

Site differentiation strategy for selective strontium uptake and elution within an all-inorganic polyoxoniobate framework

Selective uptake and elution of trace amounts of hazardous radioactive 90Sr from large-scale high-level liquid waste (HLW) is crucial for sustainable development. Here, we propose a site differentiation strategy, based on the presence of distinct selective metal capture sites (concavity site and tweezer site) within the giant polyoxoniobate (PONb) nanoclusters of an all-inorganic PONb framework (FZU-1). Through this strategy, FZU-1 can not only effectively remove 98.9% of Sr²⁺ from simulated nuclear liquid waste, performing best among the reported Sr adsorbents, but also achieve desorption of adsorbed Sr²⁺ ions by selectively loading Na⁺ ions, thus enabling the recycling of FZU-1. Based on the well-defined single-crystal structures and theoretical studies, it can be revealed that the rapid and selective uptake of Sr²⁺ is attributed to the strong binding energy between the Sr²⁺ ions and the concavity sites. The effective elution of Sr²⁺, on the other hand, stems from the preferential binding of Na⁺ ions at the tweezer sites, elevating the cluster’s electrostatic potential and indirectly facilitating the elution of Sr²⁺ ions. The exceptional stability of FZU-1, along with its rapid and selective Sr²⁺ capture and elution capabilities, positions it as a promising candidate for large-scale nuclear waste treatment and groundwater remediation applications.

Mathematical lipid correction of δ13C and effect of lipid extraction on δ15N of European eel (Anguilla anguilla) muscle: Lipid correction of δ13C in European eels.

Carbon (δ13C) and nitrogen (δ15N) stable isotope analysis is a powerful tool to investigate diverse questions in fish ecology, such as their trophic position or migration strategies. These questions appear particularly important to protect endangered European eel. However, elevated lipid content in eel muscle can bias δ13C values, as lipids are 13C-depleted compared to proteins and carbohydrates. We measured δ13C and δ15N values of bulk and lipid-free samples of eel muscle. Lipid-free samples were obtained after the extraction of lipids with cyclohexane. Lipid-corrected δ13C values, using five different mathematical equations based on bulk δ13C values, were compared to lipid-free δ13C values. We also evaluated the effect of lipid extraction on δ15N values. The analyses were based on linear regression performed on 333 individuals captured in nine lagoons and four rivers. Independently to the capture site or habitat (river or lagoon), the predicted lipid-corrected δ13C values were highly consistent with the measured lipid-free δ13C values (R2 > 0.90). The application of specific equations for each habitat or capture site only slightly increases these R2 (1.5% or less). The lipid extraction treatment significantly decreased by 0.2‰ the δ15N values compared to bulk samples. Given the excellent prediction of mathematical equations and the small decrease of δ15N values after lipids extraction, we propose to use mathematical correction to estimate δ13C values of eel muscle. As the habitats or sites did not strongly influence the results, the coefficients from our study can be applied to other studies on European eel.

The effect of downstream translocation on Atlantic salmon Salmo salar smolt outmigration success.

Trap and transport, the capture and subsequent translocation of fish during the freshwater phase of their migration, is becoming more common as a management intervention. Although the technique can be successful, it is costly and can have unintended effects on the fish being transported. This study investigates whether trap and transport can be used to increase the migration success of Atlantic salmon, Salmo salar, smolts in naturally flowing rivers. Seaward-migrating S. salar (n = 294) from two UK rivers were tracked using acoustic telemetric techniques. Outmigration success and timing were compared between non-transported (released at the original in-river capture site) and transported (released ca. 23 km downstream of the capture site) individuals. Downstream translocation increased the proportion of fish that successfully migrated to marine waters, and there was no indication that transport reduced post-release survival. The post-release migration speed of transported fish was slower than expected but this was likely a function of their advanced migration timing rather than an inhibition of their capacity to migrate. These results suggest that trap and transport can increase the outmigration success of S. salar smolts, but the earlier river exit dates of transported fish could negatively affect their survival at sea.

CO2 high-pressure miscible flooding and storage technology and its application in Shengli Oilfield, China

There are various issues for CO2 flooding and storage in Shengli Oilfield, which are characterized by low light hydrocarbon content of oil and high miscible pressure, strong reservoir heterogeneity and low sweep efficiency, gas channeling and difficult whole-process control. Through laboratory experiments, technical research and field practice, the theory and technology of CO2 high pressure miscible flooding and storage are established. By increasing the formation pressure to 1.2 times the minimum miscible pressure, the miscibility of the medium-heavy components can be improved, the production percentage of oil in small pores can be increased, the displacing front developed evenly, and the swept volume expanded. Rapid high-pressure miscibility is realized through advanced pressure flooding and energy replenishment, and technologies of cascade water-alternating-gas (WAG), injection and production coupling and multistage chemical plugging are used for dynamic control of flow resistance, so as to obtain the optimum of oil recovery and CO2 storage factor. The research results have been applied to the Gao89-Fan142 in carbon capture, utilization and storage (CCUS) demonstration site, where the daily oil production of the block has increased from 254.6 t to 358.2 t, and the recovery degree is expected to increase by 11.6 percentage points in 15 years, providing theoretical and technical support for the large-scale development of CCUS.

Air plasma fast-induced defect-enriched carbon cloth for simultaneous electrochemical detection of dopamine and uric acid

Herein, we report a fast (10 min) and simple surface treatment of pure carbon cloth (CC) only by an air plasma. The structural characterizations indicate that the air plasma process brings out higher rugosity, more defects, and increased oxygen-related groups on CC surfaces than Ar- or N2-plasma, which can offer abundant capture sites, large electroactive area, and superhydrophilic interface for analytes. As a result, the air-treated CC (CC−PAir) electrode achieves a pronounced improvement of electrocatalytic activity for the [Fe(CN)6]3-/[Fe(CN)6]4- probe evidenced by increased peak currents, decreased peak-to-peak separation, and the lowered resistance of charge transfer. It is also demonstrated that the self-supported CC−PAir electrode possesses excellent sensing performance toward dopamine (DA) and uric acid (UA). The feasibility of the simultaneous electrochemical detection of DA and UA can be verified by their large peak potential gap (∼112 mV) for differential pulse voltammetry. The chronoamperometric sensor yields wide linear ranges of 0.05–100 μM for DA and 0.5–300 μM for UA. The corresponding detection limits are estimated to be 2.6 and 20.4 nM for DA and UA, respectively. The sensor also displays satisfactory selectivity, stability, and reproducibility. Due to good flexibility, the CC−PAir electrode presents great potential for manufacturing wearable and soft electronics for human health monitoring.

Generation controllable optical chain using an optical pen.

An aperiodic snake-like optical chain has been proposed and generated by using an optical pen technique, whose numbers and positions of focal points are controllable. Moreover, by introducing a fan phase together with a twisted phase into the optical pen technique, a self-rotation optical chain can be obtained; meanwhile, it transforms the bright optical chain into a twisted optical chain with a rotating hollow region in a three-dimensional (3D) space. The properties of the rotatable focal points and the variable diameters of cross-sectional intensities during the propagation of the optical chain are demonstrated in the experimental results. Consequently, this research framework can be applied in the techniques such as deep multiplexing and rotation angle multiplexing while also enabling the realization of multiple capture sites and more intricate manipulations.

Navigating discreetly: Spatial ecology of urban wild boar in Bordeaux City's landscape of fear, France

An exemplary urban adapter, the wild boar (Sus scrofa) has successfully colonized urban ecological niches worldwide. Improvement of strategies for optimal management of urban wild boar need to gather more empirical evidence of their spatial ecology. This study is based on GPS tracking and capture-mark-recapture (CMR) of 10 and 59 wild boar, respectively, captured in Bordeaux Metropolis (France). It shows that wild boar have become urban dwellers, with intra-urban home ranges varying from 1.3 to 64.6 km2 (MCP 100 %) and from 0.5 to 9.6 km2 (KDE 95 %), depending on urban conditions. CMR results confirm the low propensity to move away from urban areas (with a mean distance of 2 km between capture and recapture sites), despite a relatively low one-year survival rate since capture (47.5 %), primarily attributable to removal efforts. Wild boar strongly depended on urban woods, mostly during daytime resting, and highly frequented urban meadows during night foraging. Their use of urban agricultural areas was minimal, but they were mostly monitored following corn and grape harvests. Wild boar mitigated the risk associated with close proximity to humans by: a nocturnal activity (72.2 % of active locations registered from sunset to sunrise), which could also be partially attributed to their sensitivity to heat; a strong use of covered habitats, especially during daytime resting and when close to buildings and roads; and a low mobility during night-time foraging (1974 m average daily distance travelled). Moreover, we demonstrate high inter- and intra-individual variability in the spatio-temporal behaviour of urban wild boar. Finally, we discuss the gap between these results and the narratives surrounding the spatial ecology of urban wild boar. Our results not only confirm the species' ability to adapt to urban environments, but also highlight their behavioural flexibility, underscoring the relevance of significant changes in representations and management activities to mitigate human-urban wild boar conflicts.

Relationship of different left bundle branch pacing sites and clinical outcomes in patients with heart failure

BackgroundLeft bundle branch pacing (LBBP) is a novel physiological pacing modality. However, whether it delivers comparable efficacy with different capture sites in patients with heart failure remains unclear. ObjectiveThis study aimed to assess the association between different pacing sites and the response of LBBP. MethodsForty-three consecutive patients with heart failure, referred for successful LBBP implantation, were prospectively recruited in this study. Patients were assigned to 3 subgroups according to the paced QRS complex morphology (left bundle branch trunk pacing [LBTP], left posterior fascicular pacing, or left anterior fascicular pacing groups). Echocardiograms and electrocardiograms were recorded and analyzed at baseline and 6-month follow-up. ResultsThe response rate was 95.0%, 88.2%, and 83.3% in LBTP, left posterior fascicular pacing, and left anterior fascicular pacing groups, respectively. All subgroups were efficient in narrowing the QRS complex (QRS complex narrowing: 38.1 ± 10.8 ms, 36.4 ± 12.6 ms, and 40.8 ± 10.8 ms) and improving cardiac function (LVEF improvement： 25.7% ± 8.1%, 15.3% ± 8.1%, and 18.8% ± 4.4%). Compared with left fascicular pacing, LBTP resulted in longer peak left ventricular activation time (76.5 ± 10.2 ms vs 82.3 ± 6.5 ms; P = .037) and shorter duration from intrinsicoid deflection in V1 or V2 to QRS end (128.0 ± 6.0 ms vs 113.3 ± 5.2 ms; P＜.0001), along with better improvement in septal systolic longitudinal strain (P = .007) and lateral-septal myocardial loading inhomogeneity (P = .036). Linear regression analysis further revealed that left bundle branch capture sites were strongly associated with the improvement in peak strain dispersion (model R2 = 0.586; P = .042) and LVEF (model R2 = 0.425; P < .0001). ConclusionDifferent left bundle branch capture sites led to a subtle difference in mechanical synchrony, which may, in turn, affect LVEF improvement in patients with heart failure.

Prevalence of dengue, Zika, and chikungunya virus infections among mosquitoes in Asia: A systematic review and meta-analysis

BackgroundDengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV) continue to pose significant public health risks. This study aims to assess the prevalence of these arbovirus infections in field-caught mosquitoes across Asia. MethodsStudies published after the year 2000 on DENV, ZIKV, and/or CHIKV infections in Asian mosquitoes were identified from Embase, Scopus, PubMed, and Ovid. A random-effects model estimated the pooled prevalence, defined as the overall prevalence from included studies, adjusted for variability among the studies. Meta-regression models were used to evaluate the association between predictors and their prevalence. ResultsA total of 2529 articles were retrieved; 57 met the inclusion criteria. Pooled prevalence of DENV, ZIKV, and CHIKV infections in Asian mosquitoes were 5.85%, 2.15%, and 1.26%, respectively. Subgroup analysis revealed varying DENV prevalence across regions: East Asia (3.32%), South Asia (5.26%), and Southeast Asia (6.92%). Univariate regression analysis demonstrated significant associations between mosquito capture site and DENV prevalence (P < 0.001), and between study region and ZIKV prevalence (P = 0.005). However, no significant predictors were identified for CHIKV prevalence. ConclusionOur findings provide reference pooled summary estimates of arbovirus infections in mosquitoes, offering crucial insight into the regional disease burden and - guidance in the development and implementation of arbovirus surveillance in mosquitoes.

Decremental conduction property in the slow conduction zone of adenosine-sensitive atrial tachycardia.

In the case of adenosine-sensitive atrial tachycardia originating near the atrioventricular (AV) node, overdrive pacing from the anterior right atrium showed constant and progressive fusion, indicating that the pacing site is proximal to slow conduction. Shortening the pacing cycle length prolonged conduction times to the orthodromic capture sites; they remained unchanged at the antidromic capture sites. Limited decremental conduction property in the slow conduction zone supports the hypothesis that AV node-like tissue remnants along the AV annulus are involved.

Value of high-output pace-mapping of the right phrenic nerve for enabling safe radiofrequency ablation of atrial fibrillation: insights from three-dimensional computed tomography segmentation.

Right phrenic nerve (RPN) injury is a disabling but uncommon complication of atrial fibrillation (AF) radiofrequency ablation. Pace-mapping is widely used to infer RPN's course, for limiting the risk of palsy by avoiding ablation at capture sites. However, information is lacking regarding the distance between the endocardial sites of capture and the actual anatomic RPN location. We aimed at determining the distance between endocardial sites of capture and anatomic CT location of the RPN, depending on the capture threshold. In consecutive patients undergoing AF radiofrequency ablation, we defined the course of the RPN on the electroanatomical map with high-output pacing at up to 50 mA/2 ms, and assessed RPN capture threshold (RPN-t). The true anatomic course of the RPN was delineated and segmented using CT scan, then merged with the electroanatomical map. The distance between pacing sites and the RPN was assessed. In 45 patients, 1033 pacing sites were analysed. Distances from pacing sites to RPN ranged from 7.5 ± 3.0 mm (min 1) when RPN-t was ≤10 mA to 19.2 ± 6.5 mm (min 9.4) in cases of non-capture at 50 mA. A distance to the phrenic nerve > 10 mm was predicted by RPN-t with a ROC curve area of 0.846 [0.821-0.870] (P < 0.001), with Se = 80.8% and Sp = 77.5% if RPN-t > 20 mA, Se = 68.0% and Sp = 91.6% if RPN-t > 30 mA, and Se = 42.4% and Sp = 97.6% if non-capture at 50 mA. These data emphasize the utility of high-output pace-mapping of the RPN. Non-capture at 50 mA/2 ms demonstrated very high specificity for predicting a distance to the RPN > 10 mm, ensuring safe radiofrequency delivery.

Combined demographic, ecological and genetic tools reveal connectivity within a fragmented butterfly population

Protected species require targeted studies to establish population sizes, their dispersal capacity and the possible genetic bottleneck effect that could impair the future of the remaining populations. In this study, we used the genotyping-by-sequencing technique (SNP: single nucleotide polymorphism) combined with Capture-Mark-Recapture (CMR) method to measure the dispersal ability and subpopulation sizes of the protected butterfly Zerynthia polyxena in 14 sites of NW Italian Alps. The study species form a metapopulation divided into several small subpopulations (ranging from 90 to 859 estimated subpopulation sizes). The species showed low mobility, likely due to habitat fragmentation, with individuals travelling an average of 80 m from their original capture site. SNPs highlighted high observed heterozygosity, low genetic substructuring at short distances, and large genetic differentiation only for individuals found in sites located at 46 km distance, suggesting high gene flow at short distances and limited gene flow between distant populations. Although CMR data did not detect movement beyond 700 m, the genetic results revealed remarkable connectivity among nearby subpopulations. The results indicate that gene flow still exists among the subpopulations despite the fragmented habitat. Considering that the species is locally threatened by habitat loss due to the planning of a European high-speed railway, our data suggest that it is not too late to adopt conservation measures. In conclusion, combining genetic and ecological studies can be utilised to design proper conservation plans for protected and threatened insect metapopulations.

Mercury Exposure Is Associated with Urbanization but not Salmonella Status in White Ibis (Eudocimus albus).

Mercury (Hg) is a ubiquitous contaminant in wetlands that can cause immunosuppression in birds, which may increase susceptibility to colonization with Salmonella spp. Previously, we found that White Ibis (Eudocimus albus), a recently urbanized wading bird, shed Salmonella spp. at a higher prevalence when captured at urban sites, compared with natural sites. In this study, we sought to determine if Hg burdens in ibis are related to Salmonella status or degree of urbanization or both. We analyzed feathers from 94 ibis in Palm Beach County, Florida, USA, along an urbanization gradient (0-68% urbanization) and from individuals with confirmed Salmonella spp. status (shedding or not shedding). We detected Hg in all ibis feathers (0.22-8.47 mg/kg; mean=1.96 mg/kg; SD=1.94). The Hg concentration was not significantly correlated to Salmonella spp. shedding status (Wilcoxon rank sum test, W=1170; P=0.596) but was negatively associated with capture site urbanization level (R2=0.327; P=0.026). Our findings may suggest that the immunosuppressive effects of Hg do not affect Salmonella shedding in the ibis or that Hg burdens were too low to affect Salmonella shedding status. Further, ibis that were captured in high urbanization sites appeared to have a lower risk of Hg exposure than ibis that were captured within low urbanization sites.

Unveiling Mechanistic Insight into Accelerating Oxygen Molecule Activation by Oxygen Defects in Co3O4-x/g-C3N4 p-n Heterojunction for Efficient Photo-Assisted Uranium Extraction from Seawater.

Photo-assisted uranium extraction from seawater (UES) is regarded as an efficient technique for uranium resource recovery, yet it currently faces many challenges, such as issues like biofouling resistance, low charge separation efficiency, slow carrier transfer, and a lack of active sites. Based on addressing the above challenges, a novel oxygen-deficient Co3O4-x/g-C3N4 p-n heterojunction is developed for efficient photo-assisted uranium extraction from seawater. Relying on the defect-coupling heterojunction synergistic effect, the redistribution of molecular charge density formed the built-in electric field as revealed by DFT calculations, significantly enhancing the separation efficiency of carriers and accelerating their migration rate. Notably, oxygen vacancies served as capture sites for oxygen, effectively promoting the generation of reactive oxygen species (ROS), thereby significantly improving the photo-assisted uranium extraction performance and antibacterial activity. Thus, under simulated sunlight irradiation with no sacrificial reagent added, Co3O4-x/g-C3N4 extracted a high uranium extraction amount of 1.08mgg-1 from 25 L of natural seawater after 7 days, which is superior to most reported carbon nitride-based photocatalysts. This study elaborates on the important role of surface defects and inerface engineering strategies in enhancing photocatalytic performance, providing a new approach to the development and design of uranium extraction material from seawater.

Natural lignin nanoparticles target tumor by saturating the phagocytic capacity of Kupffer cells in the liver

Ligand-receptor recognition serves as the fundamental driving force for active targeting, yet it is still constrained by off-target effects. Herein, we demonstrate that circumventing or blocking the mononuclear phagocyte system (MPS) are both viable strategies to address off-target effects. Naturally derived lignin nanoparticles (LNPs) show great potential to block MPS due to its good stability, low toxicity, and degradability. We further demonstrate the impact of LNPs dosage on in vivo tumor targeting and antitumor efficacy. Our results show that a high dose of LNPs (300 mg/kg) leads to significant accumulation at the tumor site for a duration of 14 days after intravenous administration. In contrast, the low-dose counterparts (e.g., 50, 150 mg/kg) result in almost all LNPs accumulating in the liver. This discovery indicates that the liver is the primary site of LNP capture, leaving only the surplus LNPs the chance to reach the tumor. In addition, although cell membrane-engineered LNPs can rapidly penetrate tumors, they are still prone to capture by the liver during subsequent circulation in the bloodstream. Excitingly, comparable therapeutic efficacy is obtained for the above two strategies. Our findings may offer valuable insights into the targeted delivery of drugs for disease treatment.

Hydrogen trapping behavior in IVB-VB transition metal carbides

The hydrogen capture mechanism of transition metal carbides is crucial to improve the hydrogen embrittlement resistance of steel materials. Although numerous experimental and theoretical studies have been carried out, the mechanism of hydrogen capture in these carbides has not been fully elucidated. In this paper, the ability of transition metal carbides (TMCs; TM=Ti, Zr, Hf, V, Nb and Ta) to capture hydrogen is studied by first-principles calculations. It is found that there is a strong correlation between the hydrogen solubility energy and the number of valence electrons of IV-VB transition metal carbides. With the increase of the number of valence electrons, the hydrogen solubility energy decreases, which indicates that IVB transition metal carbides have strong hydrogen capture ability. Compared with interstitial sites, the mechanism by which carbon vacancies are more stable hydrogen capture sites is to enhance the capture stability of hydrogen atoms by reducing the effect of chemical and mechanical effects on the dissolution energy of hydrogen atoms. In the interstitial site, hydrogen atoms tend to occupy the triangular site (TMCs-TM) surrounded by three transition metal atoms and one carbon atom. The bonding interaction between the hydrogen atom and the nearest carbon atom is the main factor affecting the stability of hydrogen atom capture.

Bacterial pathogens in Ixodes ricinus collected from lizards Lacerta agilis and Zootoca vivipara in urban areas of Wrocław, SW Poland– preliminary study

The aim of this study was to determine the level of infection of Ixodes ricinus ticks with pathogens (Borrelia spp., Rickettsia spp., and Anaplasma spp.) collected from Lacerta agilis and Zootoca vivipara lizards in the urban areas of Wrocław (SW Poland). The study was carried out in July-August 2020. Lizards were caught by a noose attached to a pole or by bare hands, identified by species, and examined for the presence of ticks. Each lizard was then released at the site of capture. Ticks were removed with tweezers, identified by species using keys, and molecular tests were performed for the presence of pathogens. From 28 lizards (17 specimens of Z. vivipara and 11 specimens of L. agilis) a total of 445 ticks, including 321 larvae and 124 nymphs, identified as I. ricinus were collected. A larger number of ticks were obtained from L. agilis compared to Z. vivipara. Molecular tests for the presence of pathogens were performed on 445 specimens of I. ricinus. The nested PCR method for the fla gene allowed the detection of Borrelia spp. in 9.4% of ticks, and it was higher in ticks from L. agilis (12.0%) than from Z. vivipara (1.0%). The RFLP method showed the presence of three species, including two belonging to the B. burgdorferi s.l. complex (B. lusitaniae and B. afzelii), and B. miyamotoi. The overall level of infection of Rickettsia spp. was 19.3%, including 27.2% in ticks collected from Z. vivipara and 17.0% from L. agilis. Sequencing of randomly selected samples confirmed the presence of R. helvetica. DNA of Anaplasma spp. was detected only in one pool of larvae collected from L. agilis, and sample sequencing confirmed the presence of (A) phagocytophilum. The research results indicate the important role of lizards as hosts of ticks and their role in maintaining pathogens in the environment including urban agglomeration as evidenced by the first recorded presence of (B) miyamotoi and (A) phagocytophilum in I. ricinus ticks collected from L. agilis. However, confirmation of the role of sand lizards in maintaining (B) miyamotoi and A. phagocytophilum requires more studies and sampling of lizard tissue.

Winter GPS tagging reveals home ranges during the breeding season for a boreal-nesting migrant songbird, the Golden-crowned Sparrow.

Determining space use for species is fundamental to understanding their ecology, and tracking animals can reveal insights into their spatial ecology on home ranges and territories. Recent technological advances have led to GPS-tracking devices light enough for birds as small as ~30 g, creating novel opportunities to remotely monitor fine-scale movements and space use for these smaller species. We tested whether miniaturized GPS tags can allow us to understand space use of migratory birds away from their capture sites and sought to understand both pre-breeding space use as well as territory and habitat use on the breeding grounds. We used GPS tags to characterize home ranges on the breeding grounds for a migratory songbird with limited available breeding information, the Golden-crowned Sparrow (Zonotrichia atricapilla). Using GPS points from 23 individuals across 26 tags (three birds tagged twice), we found home ranges in Alaska and British Columbia were on average 44.1 ha (95% kernel density estimate). In addition, estimates of territory sizes based on field observations (mean 2.1 ha, 95% minimum convex polygon [MCP]) were three times smaller than 95% MCPs created using GPS tags (mean 6.5 ha). Home ranges included a variety of land cover classes, with shrubland particularly dominant (64-100% of home range cover for all but one bird). Three birds tracked twice returned to the same breeding area each year, supporting high breeding site fidelity for this species. We found reverse spring migration for five birds that flew up to 154 km past breeding destinations before returning. GPS-tracking technology allowed for critical ecological insights into this migratory species that breeds in very remote locations.

Home range, habitat use and capture-release of translocated leopards in Gir landscape, Gujarat, India.

Understanding the spatial ecology of translocated leopards (Panthera pardus fusca) is crucial for their conservation and the effective assessment of conflict management strategies. We investigated the home range and habitat preferences of five radio-collared leopards (n = 5; 2 males; 3 females) in the Gir landscape. Additionally, we examined the usefulness of the capture-release strategy for these animals. We assessed home range and habitat selection using kernel density estimation (at 95% and 50% levels) and compositional analysis. Our findings revealed that leopards exhibited distinct patterns of movement, often returning to their original capture site or nearby locations or exploring new areas within 3 to 25 days, covering distances ranging from 48 to 260 km. The average home range (95% FK) was estimated at 103.96±36.37 (SE) km2, with a core area usage (50% FK) of 21.38±5.95 km2. Seasonally, we observed the largest home ranges during summer and the smallest during winter. Males exhibited larger home ranges (95% FK, 151±64.28 km2) compared to females (56.18±14.22 km2). The habitat analysis indicated that agricultural areas were consistently preferred in the multi-use landscape at the 2nd order habitat selection level. Additionally, habitat around water bodies was highly favoured at the 3rd order, with distinct variations in habitat selection observed during day and night. This study highlights the significance of riverine and scrubland habitats, as leopards exhibited strong preferences for these habitats within their home ranges. We emphasize the importance of conserving natural habitat patches, particularly those surrounding water bodies. We also report on the characteristics of the capture-release strategy and provide our observations indicating no escalated aggression by leopards' post-release. In conclusion, this study evaluates widely employed approaches to conflict mitigation and suggests the continuous review and assessment of management strategies for mitigating human-leopard conflicts.