Original Capture Research Articles

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.

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.

Homing of translocated native Indian pythons in Moyar River Valley, South India

Homing is often a critical aspect of an animal's behavioural and spatial ecology. Translocation is considered to be a wildlife management strategy that could reduce human-wildlife confrontation, but this strategy may not be effective if animals attempt to home to their original capture location. Translocation of animals from sites where possible human-wildlife interaction occurs is a widespread but controversial intervention to resolve conflicts. In India, snakes are often the subject of such translocations, but there is a paucity of information on the behaviour of translocated snakes compared to resident snakes. The Indian python (Python molurus), one of the largest carnivores in the Indian subcontinent, is classified as Near Threatened by the IUCN. We conducted a two-year radio-tracking study (December 2018 to December 2020) on the movements of 14 adult Indian pythons in the Moyar River Valley, within the Sathyamangalam and Mudumalai Tiger Reserves. Eleven of the 14 pythons were translocated 0.28–55.7 kms from their capture locations, while 3 pythons were not translocated: 6 were translocated short distances (<5 km from capture; range 0.28–4.67 kms), 2 were translocated to medium distances (9–11 kms from capture location), and 3 were translocated to long distances (21–55.7 kms from capture location). Four of the six snakes translocated short distances all returned to within 500 m of their original capture locations, and all 6 returned over 60 % of the translocated distance to the initial capture location. Of the two snakes translocated medium distances, both returned to within 1.1 km of the capture location (∼90 % of the distance home). None of the three snakes that were translocated long distances successfully returned to their capture locations. Translocated pythons exhibited greater net movement distances than resident snakes within the first 2 months of release. Based on these results, long-distance translocation may be an effective strategy to minimize human-python conflict, while short or medium distance translocation is unlikely to be successful. However, more research is needed about the long-term survival of translocated snakes as well as soft-release methodologies that could prevent aberrant movement behaviour directly following release.

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.

Examining Property Value Increment along Greenways: A Hedonic Pricing Analysis in Chengdu, China

Examining Property Value Increment along Greenways: A Hedonic Pricing Analysis in Chengdu, China

Spatial ecology of translocated raccoons

Raccoons (Procyon lotor) are routinely translocated both legally and illegally to mitigate conflicts with humans, which has contributed to the spread of rabies virus across eastern North America. The movement behavior of translocated raccoons has important ramifications for disease transmission yet remains understudied and poorly quantified. To examine the spatial ecology of raccoons following experimental translocation, we performed reciprocal 16 km-distance translocations of 30 raccoons between habitats of high and low raccoon density (bottomland hardwood and upland pine, respectively) across the Savannah River Site (SRS) in Aiken, South Carolina, USA (2018–2019). Translocation influenced patterns of raccoon space use, with translocated animals exhibiting a 13-fold increase in 95% utilization distributions (UDs) post- compared to pre-translocation (mean 95% UD 35.8 ± 36.1 km2 vs 1.96 ± 1.17 km2). Raccoons originating from upland pine habitats consistently had greater space use and larger nightly movement distances post-translocation compared to raccoons moved from bottomland hardwood habitats, whereas these differences were generally not observed prior to translocation. Estimated home ranges of male raccoons were twice the area as estimated for female raccoons, on average, and this pattern was not affected by translocation. After a transient period lasting on average 36.5 days (SD = 30.0, range = 3.25–92.8), raccoons often resumed pre-experiment movement behavior, with 95% UD sizes not different from those prior to translocation (mean = 2.27 ± 1.63km2). Most animals established new home ranges after translocation, whereas three raccoons moved > 16 km from their release point back to the original capture location. Four animals crossed a 100-m wide river within the SRS post-translocation, but this behavior was not documented among collared raccoons prior to translocation. Large increases in space use combined with the crossing of geographic barriers such as rivers may lead to elevated contact rates with conspecifics, which can heighten disease transmission risks following translocation. These results provide additional insights regarding the potential impacts of raccoon translocation towards population level risks of rabies outbreaks and underscore the need to discourage mesocarnivore translocations to prevent further spread of wildlife rabies.

Effects of translocation on American crocodile movements and habitat use in South Florida

AbstractThe range of the threatened American crocodile (Crocodylus acutus) in the United States is limited to the southernmost parts of Florida. As this species has recovered concurrently with an increasing human population, human–crocodile conflicts have also increased. Resolving conflicts can involve translocating crocodiles; however, they often return to the site from which they were removed. We examined the effects of translocation on crocodile movements, habitat use, body condition, and survival in Florida, USA, in 2018–2019 to refine recommendations for managers considering translocation to resolve human–crocodile conflict. We captured and attached global positioning system (GPS) units to 17 crocodiles, 10 of which served as a reference group (free‐ranging crocodiles released at their capture site) and 7 served as a treatment group (crocodiles that were translocated 14–158 km from their capture site). We collected location data from individual crocodiles for 34–661 days ( ~ 250 days for each group). Body condition was similar for both groups. Corticosterone levels measured periodically during handling indicated that crocodiles experienced increasing stress levels during handling. Three crocodiles translocated ≤45 km from their original capture site returned to that location within 13 days. Three crocodiles translocated ≥110 km did not return. One female translocated 152 km was recaptured 0.42 km from its original capture site 965 days after its release. We identified 2 states of characteristic movement patterns: state 1 indicated individuals moving slowly and somewhat randomly, and state 2 indicated individuals exhibiting fast, active directional movement. Translocated individuals were more likely than reference individuals to switch to, and stay in, state 2. Because of concerns regarding return rates and heightened stress as a result of capture and translocation, we suggest crocodile translocations have limited conservation value and may only be worth considering once all other reasonable options are exhausted.

Movement and Genomic Methods Reveal Mechanisms Promoting Connectivity in a Declining Shorebird: The Lesser Yellowlegs

Integrating tracking technology and molecular approaches provides a comprehensive picture of contemporary and evolutionary mechanisms promoting connectivity. We used mitochondrial DNA and double digest restriction-site associated DNA (ddRAD) sequencing combined with satellite telemetry to investigate the connectivity of geographically disparate breeding populations of a declining boreal shorebird, the lesser yellowlegs (Tringa flavipes). We were able to track 33 individuals on their round-trip migrations to Central and South America and back to the boreal wetlands of North America. Nearly all (93%) adults captured on the breeding grounds returned to within 5 km of the original capture site, with a median dispersal distance of 629 m. While our telemetry data revealed limited breeding dispersal in adults, genetic data uncovered significant interconnectedness across the species’ range. Very little genetic structure was estimated at ddRAD autosomal (ΦST = 0.001), Z-linked (ΦST = 0.001), and mtDNA loci (ΦST = 0.020), and maximum likelihood-based clustering methods placed all individuals in a single cluster regardless of capture location, indicating the species is panmictic. Our data indicate that large-scale juvenile dispersal is the main mechanism maintaining connectivity in this species, resulting in the absence of genomic structure.

Assessing translocation success and long‐distance homing in riverine turtles 10 years after a freshwater oil spill

AbstractWildlife translocation is often used as a mitigation strategy for construction projects and other disturbances to habitat. In 2010, one of the largest freshwater oil spills in the United States occurred in the Kalamazoo River in Michigan, when over 3.2 million L of diluted bitumen crude oil impacted nearly 56 km of riverine habitat. During 2010 and 2011 cleanup efforts, 686 northern map turtles (Graptemys geographica) were captured from oil‐impacted stretches of the river, cleaned, rehabilitated, and translocated 2.5–84.3 km from their original capture location. The goal of this translocation effort was to release turtles within the same watershed, but away from ongoing cleanup operations, so individuals could potentially return to their original home range after it had been cleaned of oil and restored. In this study, we evaluated the success of translocation as an emergency mitigation strategy for freshwater turtles by quantifying recapture probability and homing by northern map turtles translocated varying distances from their home ranges. During subsequent years of survey up to 10 years post‐spill, 230 of the translocated turtles were recaptured, of which 104 exhibited homing by returning to their original home ranges. Turtles translocated to sites nearest their original capture location had a higher probability of recapture and homing than those translocated further away. Females had a higher probability of returning to original home ranges than males when translocated greater distances. In addition, four females and one male are known to have traveled &gt;50 km between capture and release locations, which to our knowledge is the greatest travel distance recorded for any freshwater turtle species in the United States. Our results demonstrate that riverine turtles have considerable homing ability when displaced long distances, which has important implications for design and success of translocation projects.

Salamander Movement Propensity Resists Effects of Supraseasonal Drought

Movement can act as an effective strategy used by amphibians to avoid detrimental environmental conditions, particularly drought. However, due to the unpredictable nature of droughts, evaluating the patterns and consequences of movement has rarely been investigated. In 2007–2008, the southeastern United States experienced a supraseasonal drought that resulted in 110 yr low flow levels among the first-order streams. In this study, 61 months of mark–recapture data collected from one first-order stream were used to examine the effects of drought on the movement frequency distribution, survival, and growth rates of adult Desmognathus fuscus (Northern Dusky Salamander). We hypothesized that salamanders would demonstrate a higher propensity to move during supraseasonal drought conditions and that moving salamanders would experience higher survival and growth rates. We found that salamanders were more likely to move immediately after the drought compared to the pre-drought and drought conditions. Although movement frequency was low during the drought, survival was higher for individuals who moved during drought conditions in comparison to individuals who remained in their original capture location. Although our model did not detect a trend, salamanders experienced slightly higher growth in the post-drought conditions compared to drought and pre-drought conditions. In addition, during the post-drought, salamanders that moved had slightly higher growth rates compared to salamanders who remained in their original capture location. Our results suggest that adult salamanders were potentially displaying an adaptive movement strategy to resist drought conditions by moving away from affected (i.e., dry) areas within the study stream. In addition, movement was likely utilized to access replenished resources in other areas after the severe effects of the drought ended. Therefore, both in-stream and riparian barriers that impede movement may inhibit resilience of stream amphibians during severe droughts.

A robust sp2 carbon-conjugated COF for efficient iodine uptake

Synthesis of fully sp2-carbon conjugated covalent organic frameworks (COFs) is generally considered extremely challenging due to the low reversibility of the CC bond. Herein, a novel sp2-carbon conjugated COF material, named sp2c-TFPA-pXD, was prepared by Knoevenagel reaction employing tris(4-formylphenyl)amine with triangular geometry as the knot and p-xylylene dicyanide with symmetric structure as the linker unit. The CC linkages topologically connect the two precursors to a fully sp2-carbon conjugated 2D lattice and develop an eclipsed layer framework, giving sp2c-TFPA-pXD outstanding stability. The prepared sp2c-TFPA-pXD does not decompose in nitrogen atmosphere up to 323 °C, and can be stably present in boiling water, acids, bases and common organic solvents. The excellent chemical and thermal stability of sp2c-TFPA-pXD makes it suitable for the harsh environment of radioiodine treatment. In fact, sp2c-TFPA-pXD shows moderate iodine capture capacity in iodine vapor (1.22 g/g), and also shows acceptable iodine capture performance under real industrial conditions of high temperatures and low iodine concentrations. The iodide capture properties of sp2c-TFPA-pXD can be attributed to its regular channels and sp2-carbon conjugate structure. In addition, sp2c-TFPA-pXD can be reused by simple ethanol soaking treatment, and can almost maintain its original iodine capture performance after five cycles. In addition, sp2c-TFPA-pXD also displays noteworthy capability as adsorbent for iodine in cyclohexane solution. Our study confirms that sp2c-TFPA-pXD is an excellent candidate material for capturing iodine from air and solutions in harsh environments. We hope that the report of sp2c-TFPA-pXD for iodine capture could open up new avenues for sp2-carbon conjugated COFs applications and encourage more research to explore the radioiodine capture potential of other stable COFs.

Free-view Face Relighting Using a Hybrid Parametric Neural Model on a SMALL-OLAT Dataset

The development of neural relighting techniques has by far outpaced the rate of their corresponding training data (e.g., OLAT) generation. For example, high-quality relighting from a single portrait image still requires supervision from comprehensive datasets covering broad diversities in gender, race, complexion, and facial geometry. We present a hybrid parametric neural relighting (PN-Relighting) framework for single portrait relighting, using a much smaller OLAT dataset or SMOLAT. At the core of PN-Relighting, we employ parametric 3D faces coupled with appearance inference and implicit material modelling to enrich SMOLAT for handling in-the-wild images. Specifically, we tailor an appearance inference module to generate detailed geometry and albedo on top of the parametric face and develop a neural rendering module to first construct an implicit material representation from SMOLAT and then conduct self-supervised training on in-the-wild image datasets. Comprehensive experiments show that PN-Relighting produces comparable high-quality relighting to TotalRelighting (Pandey et al., 2021), but with a smaller dataset. It further improves shape estimation and naturally supports free-viewpoint rendering and partial skin material editing. PN-Relighting also serves as a data augmenter to produce rich OLAT datasets beyond the original capture.

Linear discriminant analysis with generalized kernel constraint for robust image classification

Linear discriminant analysis (LDA) as a classical supervised dimensionality reduction method has shown powerful capability in various image classification tasks. The purpose of LDA seeks an optimal linear transformation that maps the original data to a low-dimensional space. Inspired by the fact that the kernel trick can capture the nonlinear similarity of features, we propose a novel generalized distance constraint dubbed intra-class and inter-class kernel constraint (IIKC). The proposed IIKC explicitly models the category kernel distance and focuses on helping the original LDA capture more discriminant features in order to further improve the separability and magnitude difference between nearby data points. Our proposed method with IIKC aims to achieve maximum category separability by minimizing the intra-class kernel distances as well as maximizing the inter-class kernel distance, simultaneously. Extensive experimental results on six publicly available benchmark databases illustrate that the LDA-based methods embedded with the proposed IIKC significantly improve the discrimination ability and achieve a better classification performance than the original and state-of-the-art LDA algorithms.

An Earth-Mars microsatellite mission leveraging low-energy capture and low-thrust propulsion

Growing interest in deep-space exploration using microsatellites is leading the development of novel trajectory design techniques compatible with the constraints of this class of spacecraft. The mission design discussed in this paper examines the possibility of injecting a microsatellite into a desired orbit around Mars taking advantage of multibody dynamics, performing Earth and Moon flybys, which concludes in a low-energy capture at Mars, followed by nonlinear control for orbit injection maneuvers. If compared to a traditional Earth-Mars transfer, the proposed solution leads to relevant propellant savings and extended launch windows, but the capture orbit established has chaotic behavior and time-varying osculating orbital parameters which may not satisfy the mission requirements. Consequently, the microsatellite is capable of transferring from the original low-energy capture orbit to the desired operative one. For this phase, the microsatellite is assumed to operate using a low-thrust propulsion system, which is ignited with the intent of driving the microsatellite toward two operational orbits: (a) a quasi-synchronous repeating 2-SOL orbit and (b) a sun-synchronous orbit with altitude of 200 km. To do this, nonlinear orbit control is employed. Convergence toward the desired operational orbits is investigated, and can be guaranteed - using the Lyapunov stability theory, in conjunction with the LaSalle invariance principle - under certain conditions related to the orbit perturbing accelerations and the low-thrust magnitude. The numerical simulations prove that the combination of multiple-flyby transfer (simulated with real ephemeris, with the use of GMAT) and low-thrust nonlinear orbit control represents a viable and effective strategy for microsatellite missions to Mars.

Euclidean Graphs as Crack Pattern Descriptors for Automated Crack Analysis in Digital Images.

Typical crack detection processes in digital images produce a binary-segmented image that constitutes the basis for all of the following analyses. Binary images are, however, an unsatisfactory data format for advanced crack analysis algorithms due to their sparse nature and lack of significant data structuring. Therefore, this work instead proposes a new approach based on Euclidean graphs as functional crack pattern descriptors for all post-detection analyses. Conveying both geometrical and topological information in an integrated representation, Euclidean graphs are an ideal structure for efficient crack path description, as they precisely locate the cracks on the original image and capture salient crack skeleton features. Several Euclidean graph-based algorithms for autonomous crack refining, correlation and analysis are described, with significant advantages in both their capabilities and implementation convenience over the traditional, binary image-based approach. Moreover, Euclidean graphs allow the autonomous selection of specific cracks or crack parts based on objective criteria. Well-known performance metrics, namely precision, recall, intersection over union and F1-score, have been adapted for use with Euclidean graphs. The automated generation of Euclidean graphs from binary-segmented images is also reported, enabling the application of this technique to most existing detection methods (e.g., threshold-based or neural network-based) for cracks and other curvilinear features in digital images.

Den-Associated Behavior of Octopus rubescens Revealed by a Motion-Activated Camera Trap System.

Dens are a crucial component of the life history of most shallow water octopuses. However, den usage dynamics have only been explored in a few species over relatively short durations, and Octopus rubescens denning behavior has never been explored in situ. We built four underwater camera traps to observe the behavior of O. rubescens in and around their dens. To distinguish individuals, octopuses were captured and given a unique identifiable visible implant elastomer tag on the dorsal side of their mantle. After being tagged and photographed, each octopus was released back to its original capture site within its original den bottle. The site is unique in that octopuses reside almost exclusively in discarded bottles, therefore aiding in locating and monitoring dens. Motion-activated cameras were suspended in a metal field-of-view above bottle dens of released octopuses to observe den-associated behaviors. Cameras were regularly retrieved and replaced to allow continuous monitoring of den locations in 71 h intervals for over a month. We found that O. rubescenswas primarily active during the day and had frequent interactions with conspecifics (other members within the species). We also found that rockfish and red rock crabs tended to frequent den locations more often when octopuses were not present, while kelp greenling both visited dens more frequently and stayed longer when octopuses were present. Our results, demonstrate the utility of motion-activated camera traps for behavioral and ecological studies of nearshore mobile organisms.

The effects of maternal penning on the movement ecology of mountain caribou

AbstractTranslocation and captivity are important tools for conservation biology and wildlife management. Understanding the movement ecology of animals following their release in novel terrain is critical to predicting the success of wildlife restoration efforts. Mountain caribou have high conservation value – efforts to restore their populations across western Canada involve hundreds of millions of dollars in science, monitoring, and management activity. Here, we examined the movements of adult female caribou (N = 36) following their translocation to, and release from, a maternity pen (‘penned caribou’) and compared these movements to animals that were not translocated (‘unpenned caribou’, N = 22). A maternity pen is a temporary holding facility, within the animals’ existing range, that enables them to bear and raise their young in the absence of predators and with augmented resources. Penned and unpenned animals had similar home range sizes (1052.2 and 1314.6 km2, respectively, P = 0.46) though penned animals moved through the landscape in a faster yet less directed manner. We found some evidence that memory may improve the efficiency of space use. Home ranges with higher quality habitats tended to be smaller than home ranges with poorer quality habitats irrespective of penning status. Penned animals ranged at lower elevation (~150 m) than unpenned animals, particularly in spring and early winter. For penned animals, we did not detect evidence of homing back to the original capture site. The best predictor of how caribou will use the landscape appears to be proximity to the location of the release site. To maximize the fitness of released caribou, future plans for maternity pens and captive breeding programs need to consider the management of food, predators, and habitat across the 1000–2000 km2 that will form the home range near the release site.

Juvenile Hawksbill Turtles, Eretmochelys imbricata, in the Jardines de la Reina Archipelago, Cuba

Immature hawksbill turtles were studied in Jardines de la Reina Archipelago, the principal area of distribution for this species in Cuban waters. Hawksbill areas of occurrence, size composition, scope of movement range, and somatic growth rates are presented. A total of 496 individuals were caught while diving or with nets at depths of 0.5–2.5 m. Differences in size distribution were observed among survey areas within the Jardines de la Reina Archipelago. Mean curved carapace lengths were 35.6 ± 9.6 cm and 59.6 ± 7.7 cm for hawksbills captured in the external and internal cays, respectively. Forty-two individuals were recaptured between 1 and 4 times at intervals averaging 554.9 d. For recaptured turtles, 91% were encountered within < 1 km of their original capture location. Our findings indicate that the benthic habitats of Jardines de la Reina Archipelago are favorable for the recruitment of juvenile hawksbill turtles transitioning from pelagic habitats. The data also show that hawksbills are distributed throughout the Jardines de la Reina Archipelago study region, and that coastal foraging areas within this region host small, postpelagic juveniles as well as larger immature hawksbills that have been resident for extended periods.

Potential and limitations of LiDAR altimetry in archaeological survey. Copper Age and Bronze Age settlements in southern Iberia

Potential and limitations of LiDAR altimetry in archaeological survey. Copper Age and Bronze Age settlements in southern Iberia

Fluid Inclusion and Titanite U-Pb Age Constraints on the Yuanjiang Ruby Mineralization in the Ailao Shan-Red River Metamorphic Belt, Southwest China

ABSTRACT The Yuanjiang marble-hosted ruby deposit lies in the central segment of the Ailao Shan metamorphic massif of the Ailao Shan-Red River metamorphic belt. The mineralizing fluid and age were characterized by detailed petrography, Raman spectroscopy, microthermometry, and in situ titanite laser ablation-inductively coupled plasma-mass spectrometry dating. Some fluid inclusions in the corundum show an interesting morphology with a diaspore crystal fully separating the whole inclusion into two smaller inclusions. This morphological feature can be explained by morphological ripening and subsequent reactions between the trapped H2O and the host corundum during the cooling of the inclusion. Fluid inclusions in the ruby belong to the system CO2–H2S–COS–S8–H2S2–CH4–AlO(OH) with various daughter minerals, including diaspore, gibbsite, and native sulfur (S8). The observed seven-component fluid inclusion composition can be explained by two steps: (1) original fluid inclusion capture during deposit formation with compositions including CO2, H2S, COS, CH4, S8, and H2S2, and (2) post-entrapment fluid inclusion modification, such as diaspore and gibbsite. The presence of hydrous minerals in fluid inclusions strongly supports the idea that water was once present in the initial fluids. In the Yuanjiang deposit, petrographic evidence shows that titanite formed simultaneously with ruby, and U-Pb dating of titanite allows us to conclude that the ruby mineralization formed at 23.4 ± 0.3 Ma, in other words during the Himalayan orogeny.