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Estimating and monitoring plant population size is fundamental for ecological research, as well as conservation and restoration programs. High‐resolution imagery has potential to facilitate such estimation and monitoring. However, remotely sensed estimates typically have higher uncertainty than field measurements, risking biased inference on population status.We present a model that accounts for false negative (missed plants) and false positive (misclassified or double‐counted plants) error in counts from high‐resolution imagery via integration with ground data. We apply it to estimate the abundance of a foundational shrub species in post‐wildfire landscapes in the western United States. In these landscapes, plant recruitment is crucial for ecological recovery but locally patchy, motivating the use of spatially extensive measurements from unoccupied aerial systems (UAS). Integrating >16 ha of UAS imagery with >700 georeferenced field plots, we fit our model to generate insights into the prevalence and drivers of observation errors associated with classification algorithms used to distinguish individual plants, relationships between abundance and landscape context, and to generate spatially explicit maps of shrub abundance.Raw counts of plant abundance in high‐resolution imagery resulted in substantial false negative and false positive observation errors. The probability of detecting (p) adult plants (≥0.25 m tall) varied between sites within 0.52 < p̂adult < 0.82, whereas the detection of smaller plants (<0.25 m) was lower, 0.03 < p̂small < 0.3. On average, we estimate that 19% of all detected plants were false positive errors, which varied spatially in relation to topographic predictors. Abundance declined toward the interior of previous wildfires and was positively associated with terrain roughness.Our study demonstrates that integrated models accounting for imperfect detection improve estimates of plant population abundance derived from inherently imperfect UAS imagery. We believe such models will further improve inference on plant population dynamics—relevant to restoration, wildlife habitat and related objectives—and echo previous calls for remote sensing applications to better differentiate between ecological and observational processes. [ABSTRACT FROM AUTHOR]

Monitoring threatened species is essential for understanding their conservation needs and developing effective recovery strategies. However, designing and implementing monitoring programs can be challenging in resource‐constrained environments, where conservation practitioners must balance the need for detailed information with limited resources. We present a case study focusing on the design of a range‐wide monitoring program for the Endangered rufous scrub‐bird (Atrichornis rufescens) in the mountain forests of eastern Australia. We first developed a ‘wish list’ of monitoring questions and then trialed the methods needed for answering them using sequence of pilot studies. We implemented a phased approach comprising (i) a study of whether individuals could be identified by their songs, (ii) identification of a ‘core range’ using species distribution models to refine the search area, and (iii) a trial of the efficacy of a preferred feasible monitoring approach. We offer a practical pathway for designing question‐driven monitoring programs for threatened species. Our study highlights the importance of clarifying explicit monitoring goals and tailoring methods to suit species' ecological and life history characteristics. By following this systematic approach, conservation efforts can obtain valuable information for effective management, even with limited resources and prevailing uncertainty about species ecology. [ABSTRACT FROM AUTHOR]

The climate crisis adds multiple threats to the already long list of stressors on global biodiversity. The result is a paucity of resources and a growing list of species in need of conservation programs to secure their future. Conservation actions that deal with persistent and pervasive threats must focus on trying to understand the biology of the organism, its ecology and response to such threats without being paralysed by inaction due to gaps in knowledge. Following the devastating 2019/20 mega-fires across the east coast of Australia, a major effort to combine complementary conservation approaches to monitor and recover populations of threatened amphibians was mobilised. For one species, the cryptic Littlejohn's tree frog (Litoria littlejohni), this integrated conservation framework combined traditional ecological approaches including population monitoring, habitat creation, captive breeding and translocation, with established and emerging biotechnologies such as genetic analysis, biobanking, assisted reproduction and biomarkers of individual health. Littlejohn's tree frog was recently uplisted to Endangered, due to increased threat of extinction resulting from the fires, whilst already suffering from disease and reduced genetic diversity. Our integrated conservation approach attempts to accelerate recovery of a species threatened with multiple landscape persistent stressors that are not mitigated by singular conservation actions. Presented here as a case study, we argue this integrated approach used for Littlejohn's tree frog could be adopted for other species facing perilous population declines. [ABSTRACT FROM AUTHOR]

Phytocoenotic conditions of growth and anthropogenic management of natural phytocoenoses have a significant impact on the population characteristics and stocks/reserves of medicinal plant raw material. The article presents the results of the peculiarities of the response of spatial, dimensional, ontogenetic and vitality structures of populations of the official species - Hypericum perforatum L., and establishes a dependence that allows predicting the reserves of medicinal plant material Hyperci herba by the height of individuals. With the aim of forecasting the dynamics of the resource potential of this species, geobotanical descriptions were conducted, and classical population methods were applied: morphometric, ontogenetic and vitality analyses, as well as a number of statistical methods (correlation, factorial, dispersion, and regression analyses). It was established that the population density of H. perforatum averaged from 3 to 12, but sometimes reached 20 to 30 individuals/m2, with the maximum observed under conditions of random mowing. The minimum indicators of the vegetative sphere: height of generative individuals (h, cm), aboveground phytomass (W, g), photosynthetic effort (LWR, %) were noted in populations used as hayfields, pastures, and in agrophytocenosis. The maximum indicators were in populations that were generally or almost unaffected by anthropogenic influences. Research on the dynamics of the main morphological parameters showed that while the maximum and minimum parameters of vegetative structures differed by approximately 2.1 times, generative parameters differed by 4.6 times. Statistically significant differences were observed among H. perforatum populations in terms of the number, mass of generative organs, and the reproductive effort of plants. A statistically significant correlation was found between plant height (h, cm) and the productivity of aboveground dry phytomass, which forms the herbal raw materials (HRM, g). It is described by the Equation: HRM = 0.167h – 3.28. In hayfield-pasture areas and in agrophytocenosis, up to 60–75% of individuals were of small size and low vitality, their contribution to the production of medicinal plant raw material was insignificant. Overall, the conducted research showed that Hypericum perforatum L. exhibited significant phytocenotic diversity, which depended on a complex of ecologo-cenotic factors and types of anthropogenic management. [ABSTRACT FROM AUTHOR]

Geoffroy's spider monkeys, an endangered, fast-moving arboreal primate species with a large home range and a high degree of fission–fusion dynamics, are challenging to survey in their natural habitats. Our objective was to evaluate how different flight parameters affect the detectability of spider monkeys in videos recorded by a drone equipped with a thermal infrared camera and examine the level of agreement between coders. We used generalized linear mixed models to evaluate the impact of flight speed (2, 4, 6 m/s), flight height (40, 50 m above ground level), and camera angle (−45°, −90°) on spider monkey counts in a closed-canopy forest in the Yucatan Peninsula, Mexico. Our results indicate that none of the three flight parameters affected the number of detected spider monkeys. Agreement between coders was "substantial" (Fleiss' kappa coefficient = 0.61–0.80) in most cases for high thermal-contrast zones. Our study contributes to the development of standardized flight protocols, which are essential to obtain accurate data on the presence and abundance of wild populations. Based on our results, we recommend performing drone surveys for spider monkeys and other medium-sized arboreal mammals with a small commercial drone at a 4 m/s speed, 15 m above canopy height, and with a −90° camera angle. However, these recommendations may vary depending on the size and noise level produced by the drone model. [ABSTRACT FROM AUTHOR]

Small, fragmented, or isolated populations are at risk of population decline due to fitness costs associated with inbreeding and genetic drift. The King Island scrubtit Acanthornis magna greeniana is a critically endangered subspecies of the nominate Tasmanian scrubtit A. m. magna, with an estimated population of <100 individuals persisting in three patches of swamp forest. The Tasmanian scrubtit is widespread in wet forests on mainland Tasmania. We sequenced the scrubtit genome using PacBio HiFi and undertook a population genomic study of the King Island and Tasmanian scrubtits using a double-digest restriction site-associated DNA (ddRAD) dataset of 5,239 SNP loci. The genome was 1.48 Gb long, comprising 1,518 contigs with an N50 of 7.715 Mb. King Island scrubtits formed one of four overall genetic clusters, but separated into three distinct subpopulations when analyzed independently of the Tasmanian scrubtit. Pairwise F ST values were greater among the King Island scrubtit subpopulations than among most Tasmanian scrubtit subpopulations. Genetic diversity was lower and inbreeding coefficients were higher in the King Island scrubtit than all except one of the Tasmanian scrubtit subpopulations. We observed crown baldness in 8/15 King Island scrubtits, but 0/55 Tasmanian scrubtits. Six loci were significantly associated with baldness, including one within the DOCK11 gene which is linked to early feather development. Contemporary gene flow between King Island scrubtit subpopulations is unlikely, with further field monitoring required to quantify the fitness consequences of its small population size, low genetic diversity, and high inbreeding. Evidence-based conservation actions can then be implemented before the taxon goes extinct. [ABSTRACT FROM AUTHOR]

Amphibians are experiencing severe population declines, requiring targeted conservation action for the most threatened species and habitats. Unfortunately, we do not know the basic demographic traits of most species, which hinders population recovery efforts. We studied one of Madagascar's most threatened frog species, the harlequin mantella (Mantella cowanii), to confirm it is still present at historic localities and estimate annual survival and population sizes. We surveyed eleven of all thirteen known localities and were able to detect the species at eight. Using a naïve estimate of detection probability from sites with confirmed presence, we estimated 1.54 surveys (95% CI [1.10–2.37]) are needed to infer absence with 95% confidence, suggesting the three populations where we did not detect M. cowanii are now extirpated. However, we also report two new populations for the first time. Repeated annual surveys at three sites showed population sizes ranged from 13–137 adults over 3–8 years, with the most intensively surveyed site experiencing a >80% reduction in population size during 2015–2023. Annual adult survival was moderately high (0.529–0.618) and we recaptured five individuals in 2022 and one in 2023 first captured as adults in 2015, revealing the maximum lifespan of the species in nature can reach 9 years and beyond. Our results confirm M. cowanii is characterized by a slower life history pace than other Mantella species, putting it at greater extinction risk. Illegal collection for the international pet trade and continued habitat degradation are the main threats to the species. We recommend conservation efforts continue monitoring M. cowanii populations and reassess the International Union for Conservation of Nature (IUCN) Red List status because the species may be Critically Endangered rather than Endangered based on population size and trends. [ABSTRACT FROM AUTHOR]

Abstract Estimating and monitoring plant population size is fundamental for ecological research, as well as conservation and restoration programs. High‐resolution imagery has potential to facilitate such estimation and monitoring. However, remotely sensed estimates typically have higher uncertainty than field measurements, risking biased inference on population status. We present a model that accounts for false negative (missed plants) and false positive (misclassified or double‐counted plants) error in counts from high‐resolution imagery via integration with ground data. We apply it to estimate the abundance of a foundational shrub species in post‐wildfire landscapes in the western United States. In these landscapes, plant recruitment is crucial for ecological recovery but locally patchy, motivating the use of spatially extensive measurements from unoccupied aerial systems (UAS). Integrating >16 ha of UAS imagery with >700 georeferenced field plots, we fit our model to generate insights into the prevalence and drivers of observation errors associated with classification algorithms used to distinguish individual plants, relationships between abundance and landscape context, and to generate spatially explicit maps of shrub abundance. Raw counts of plant abundance in high‐resolution imagery resulted in substantial false negative and false positive observation errors. The probability of detecting (p) adult plants (≥0.25 m tall) varied between sites within 0.52

Abstract Population monitoring programmes typically rely on sampling because it is impossible to survey all the sites within the study area. In such a situation, the general recommendation to obtain unbiased estimates of population trends is to select monitoring sites using probability sampling. However, site selection not based on probability sampling, such as selecting sites with the largest abundance of individuals at the beginning of the monitoring programme, is common in practice. Nevertheless, these methods carry the risk of obtaining biased trend estimates. Using simulations, McClure & Rolek (2023) investigated whether three non‐probability sampling site selection methods can yield unbiased trend estimates under some specific conditions. For two of these methods, that is selecting high quality sites and selecting sites known to be occupied, the authors conclude that there is a major risk of obtaining biased trend estimates. For the third method, that is selecting sites with the largest initial abundance, they found conditions in which unbiased estimates can be obtained. They conclude that the general recommendation to use probability sampling should be revised. Here, we show that the authors' results, although perfectly correct, do not invalidate this recommendation. First, we point out that the authors made strong assumptions about the populations' functioning in their simulations, especially that inter‐annual variance in abundance is similar for all sites, which is unlikely in most real populations. We show through simple simulations that even slightly relaxing this assumption invalidates the authors' results. We also point out that for most of the hypotheses made by the authors, it is generally not known at the beginning of a study whether they will be respected. Furthermore, the authors did not provide evidence that selecting sites based on high initial abundance leads to more precise trend estimates than probability sampling methods. Therefore, neither the benefits nor the risks of this method are known. We conclude that until evidence is provided that abundance‐based site selection improves estimate precision and the situations in which it provides unbiased estimates are clearly identified, using probability sampling should remain the rule.

Phytocoenotic conditions of growth and anthropogenic management of natural phytocoenoses have a significant impact on the population characteristics and stocks/reserves of medicinal plant raw material. The article presents the results of the peculiarities of the response of spatial, dimensional, ontogenetic and vitality structures of populations of the official species - Hypericum perforatum L., and establishes a dependence that allows predicting the reserves of medicinal plant material Hyperci herba by the height of individuals. With the aim of forecasting the dynamics of the resource potential of this species, geobotanical descriptions were conducted, and classical population methods were applied: morphometric, ontogenetic and vitality analyses, as well as a number of statistical methods (correlation, factorial, dispersion, and regression analyses). It was established that the population density of H. perforatum averaged from 3 to 12, but sometimes reached 20 to 30 individuals/m2, with the maximum observed under conditions of random mowing. The minimum indicators of the vegetative sphere: height of generative individuals (h, cm), aboveground phytomass (W, g), photosynthetic effort (LWR, %) were noted in populations used as hayfields, pastures, and in agrophytocenosis. The maximum indicators were in populations that were generally or almost unaffected by anthropogenic influences. Research on the dynamics of the main morphological parameters showed that while the maximum and minimum parameters of vegetative structures differed by approximately 2.1 times, generative parameters differed by 4.6 times. Statistically significant differences were observed among H. perforatum populations in terms of the number, mass of generative organs, and the reproductive effort of plants. A statistically significant correlation was found between plant height (h, cm) and the productivity of aboveground dry phytomass, which forms the herbal raw materials (HRM, g). It is described by the equation: HRM = 0.167h - 3.28. In hayfield-pasture areas and in agrophytocenosis, up to 60–75% of individuals were of small size and low vitality, their contribution to the production of medicinal plant raw material was insignificant. Overall, the conducted research showed that Hypericum perforatum L. exhibited significant phytocenotic diversity, which depended on a complex of ecologo-cenotic factors and types of anthropogenic management.

Abstract Background Understanding how free-ranging animals behave can help in the design of optimal management strategies to both conserve species and enable individuals to express natural behaviours, maximising welfare. Animal-borne accelerometers passively collect data on body acceleration which can be interpreted to quantify behaviour. Accelerometers are increasingly used in behavioural research, however validation of accelerometer readouts to enable classification of discrete behaviours is required for each species. Pangolins are a heavily trafficked clade of mammals, all of which are considered vulnerable to extinction. They are also under-researched, with little known about their behaviour in the wild. In this study, we present the first validation of behavioural classification based on accelerometer readouts for a pangolin species; the ground pangolin (Smutsia temminckii). Results We present a standardised protocol for attaching accelerometers to pangolins to minimise the impact of devices on welfare. We match the readouts from accelerometers to behaviours defined through video observations. Using a random forest classification, we defined five discrete behaviours (walking, digging, feeding, investigating ground, and stationary, accuracy of 85%) and three activity levels (low, medium, and high, accuracy of 94%) from accelerometer readouts. We determine optimal sampling frequency and window length (50 Hz and five seconds for discrete behaviour, 10 Hz and seven seconds for activity level). We then deploy accelerometers and classify the behaviour of three free-ranging pangolins for between two and four days. We find considerable variation in peak daily activity between free-ranging pangolins with different individuals displaying nocturnal and crepuscular behaviour. We also find that pangolins spend the majority of their time (between 62 and 71%) at rest. Conclusion The methods we present will enable the quantification of ground pangolin behaviour in the wild to improve our understanding of the species’ ecology and help inform conservation efforts. This will also help to improve our fundamental understanding of animal behaviour and ecology.

Mammal populations are declining in biodiverse tropical regions. Global analyses have identified Indonesia as a hotspot of vertebrate decline, although relatively few data are available to substantiate these claims. We reviewed research articles published during 2000–2020 on 104 medium-sized to large terrestrial mammal species found in Indonesia to help inform conservation management and future research. We identified 308 peer-reviewed studies published in English or Bahasa Indonesia, with an increase in publication rate (articles published per year) over time. Studies of species distributions dominated the literature, followed by publications on abundance, species diversity and combinations of these topics. Most publications concerned single-species studies conducted at a single location and a single point in time. We identify four key issues that should be addressed by future research and conservation efforts: (1) disproportionate focus on a small number of species; (2) geographical bias towards west Indonesia (Sumatra, Kalimantan and Java–Bali), with few published studies from central (Sulawesi, Nusa Tenggara and Maluku) and east (Papua) Indonesia; (3) limitations to survey design, sampling effort and data analysis; and (4) lack of long-term wildlife population studies. We also note challenges local researchers face in publishing their studies in international journals because of language barriers and costs. Greater use of existing biodiversity data and continued capacity building for local researchers, particularly those in central and east Indonesia, are critical to effectively guide future wildlife monitoring and improve the conservation status of Indonesian mammals.

Conservation monitoring is paramount for the gathering of information on species and populations in need of conservation actions. However, monitoring of the mountain bongo Tragelaphus eurycerus isaaci, a Critically Endangered antelope endemic to Kenya, has hitherto been limited to surveillance (i.e. focused on persistence of the species in particular areas), thus limiting the information that could be retrieved on the status and trends of these populations. Using a newly developed identification system, we implemented robust design mark–recapture using existing camera-trap records of four wild subpopulations of the bongo. We provide data on sex and age structure and the first estimates of population size in the wild. Males and calves seem to be suffering higher mortality than females, and only two of the four monitored populations include adults of both sexes and calves. The combined size of these two breeding populations is estimated to be 29–50. Our findings confirm the critical situation of the mountain bongo in the wild and highlight the need for conservation actions to reinforce the wild populations for the long-term conservation of this antelope.

Assessing trends in population abundance and demographics is crucial for managing long‐lived and slow‐reproducing species. Obtaining demographic data, and age‐structure information, is challenging, notably for cetaceans. To address this, we combined Unoccupied Aerial System (UAS; drone) photogrammetry data with long‐term (>20 years) photo identification data to assess the age‐structure of the critically endangered sub‐population of common bottlenose dolphins (Tursiops truncatus) of the Gulf of Ambracia, Greece. We compared our findings with two extensively studied non‐endangered bottlenose dolphin populations (T. aduncus in Shark Bay, Australia, and T. truncatus in Sarasota Bay, USA). Using a log‐linear model, we estimated the total body lengths (TL) of 160 known‐aged dolphins between 2021 and 2023 from blowhole‐to‐dorsal‐fin distance (BHDF) measurements collected during surfacing. Subsequently, we tested four growth models to establish an age‐length growth curve. We assessed the sub‐population's age‐structure using three methods: (1) UAS‐derived TL estimates, (2) age‐length growth curve and (3) long‐term monitoring data (i.e. actual age‐structure). UAS‐measured TL (247.6 ± 32.2 cm) and UAS‐estimated TL (246.0 ± 34.7 cm) of the Greek sub‐population showed no differences. The Richards Growth model suggested an asymptotic length of 258.5 cm. In Greece, resulting age‐structure estimates across the three methods revealed no significant differences (P > 0.1). The Gulf of Ambracia and Shark Bay populations shared similar age‐structures, while Sarasota had higher proportions of 2–10 year‐olds and lower proportions of 10+ year‐olds. All populations had a comparable proportion of 0–2 year‐olds (~14%), indicating a similar reproductive rate. Our findings suggest stability in the Greek sub‐population; however, additional monitoring of reproductive parameters is essential before concluding its status. We demonstrated the effectiveness of UAS‐photogrammetry in rapidly quantifying population age‐structure, including scenarios with limited or no demographic data. This technique shows promise for enhancing precision, timeliness, cost‐effectiveness and efficiency in population monitoring and informing timely conservation management decisions. [ABSTRACT FROM AUTHOR]

Simple Summary: Over the last decade, optical sensors have demonstrated great potential to provide complementary data to monitor insect abundance. This article introduces a field-deployable and non-destructive optical instrument to monitor the abundance of flying insects, called an Entomological Bistatic Optical Sensor System, or eBoss. The study focuses on comparing abundance measurements made by the eBoss and physical traps over an 8-month field campaign. The eBoss made over 302,000 insect observations and evaluated the aerial density (#/m3) of all flying insects as well as specifically male and female mosquitoes with a 1 min resolution, allowing us to monitor both the abundance over the season and daily peak of activity. The study's objectives were to validate the optical sensor's data against physical trap collections, which confirmed the correlation between the two methods. However, the eBoss demonstrated superior temporal resolution (1 min versus approximately 3 days) and statistical power due to its larger sample size. These findings suggest that an eBoss can significantly enhance flying insect monitoring efforts, such as mosquitoes or pollinators, providing valuable insights for vector control strategies, agriculture and public health planning. Optical sensors have shown significant promise in offering additional data to track insect populations. This article presents a comparative study between abundance measurements obtained from a novel near-infrared optical sensor and physical traps. The optical instrument, named an Entomological Bistatic Optical Sensor System, or eBoss, is a non-destructive sensor operating in the near-infrared spectral range and designed to continuously monitor the population of flying insects. The research compares the mosquito aerial density (#/m3) obtained through the eBoss with trap counts from eight physical traps during an eight-month field study. The eBoss recorded over 302,000 insect sightings and assessed the aerial density of all airborne insects as well as male and female mosquitoes specifically with a resolution of one minute. This capability allows for monitoring population trends throughout the season as well as daily activity peaks. The results affirmed the correlation between the two methods. While optical instruments do not match traps in terms of taxonomic accuracy, the eBoss offered greater temporal resolution (one minute versus roughly three days) and statistical significance owing to its much larger sample size. These outcomes further indicate that entomological optical sensors can provide valuable complementary data to more common methods to monitor flying insect populations, such as mosquitoes or pollinators. [ABSTRACT FROM AUTHOR]

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

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

The Eurasian beaver is an ecosystem engineer species capable of altering the riparian vegetation and the hydrology of freshwater habitats. The study of its distribution process is therefore important for both nature conservation and conflict management. Thanks to protection efforts and natural expansion, the beaver has already inhabited most of its former range, starting from the brink of extinction. The changes in the Eurasian distribution and population size have been continuously documented in the scientific literature. In these studies, however, Hungary, as a country with an important position along the beavers' colonisation routes provided by the Danube drainage basin, has hitherto been underrepresented due to a severe lack of data. In this paper, we summarise all the available information about the thirty-year history, colonisation process, current distribution, as well as the management of the Hungarian population. Based on the newest available data, the beaver is present along all of the large rivers and along most permanent watercourses in the country. Despite the continuing growth trend of the population, a beaver management strategy has not yet been developed. Its establishment could be significantly supported by further monitoring surveys and scientific studies focusing on the region- and site-specific ecological effects of the species. [ABSTRACT FROM AUTHOR]

Monitoring population parameters of invasive species gains importance as these species continue to expand all over the world. Monitoring of invasive mammalian mesopredators is, however, complicated due to their nocturnal and secretive behaviour. In the European Union, the most common invasive mesopredator is the raccoon dog (Nyctereutes procyonoides), which causes concerns for native species, such as endangered waterfowl that may be subject to nest predation. We studied the density of mesopredators in southern Finland with wildlife cameras, using methodology of distance sampling. We deployed in total of 175 camera traps around 11 (spring 2020) and 16 (spring 2021) lakes or wetlands. We inferred densities for raccoon dogs, and for native mesopredators the red fox (Vulpes vulpes) and the European badger (Meles meles) for comparison. Raccoon dogs were found to have higher overall as well as site-specific densities (about 3.7 ind./km2) than badgers (1.2 ind./km2) and red foxes (0.6 ind./km2). The raccoon dogs also were present at every study wetland, while badgers were not found at all sites. The red fox showed more diurnal activity compared to raccoon dogs and badgers. Camera trap distance sampling enabled us to provide a density estimates on a rather small spatial and temporal scale for species of similar size and movement speed. It could therefore prove valuable as a long-term monitoring option, as climate trends are likely to further enable raccoon dog expansion. Currently this invasive species appears to be the most common mesopredator around wetlands in the southern boreal zone of southern Finland. [ABSTRACT FROM AUTHOR]

Sex pheromones play a crucial role in mate location and reproductive success. Insects face challenges in finding mates in low-density environments. The population dynamics of locusts vary greatly, ranging from solitary individuals to high-density swarms, leading to multiple-trait divergence between solitary and gregarious phases. However, differences in sexual communication between solitary and gregarious locusts have not been sufficiently explored. Herein, we found that solitary locusts but not gregarious ones heavily rely on a single compound, dibutyl phthalate (DBP), for sexual communication. DBP is abundantly released by solitary female locusts and elicits strong attraction of male solitary and gregarious locusts. Solitary adult males display much higher electrophysiological responses to DBP than adult females. Additionally, LmigOr13 was identified as the DBP-specific odorant receptor expressed in neurons housed in basiconic sensilla. Male LmigOr13-/- mutants generated by CRISPR/Cas9 have low electrophysiological responses and behavioral attraction to DBP in both laboratory and field cage experiments. Notably, the attractiveness of DBP to male locusts becomes more evident at lower population densities imposed by controlling the cage size. This finding sheds light on the utilization of a sex pheromone to promote reproductive success in extremely low-density conditions and provides important insights into alternative approaches for population monitoring of locusts. [ABSTRACT FROM AUTHOR]

Background: Understanding how free-ranging animals behave can help in the design of optimal management strategies to both conserve species and enable individuals to express natural behaviours, maximising welfare. Animal-borne accelerometers passively collect data on body acceleration which can be interpreted to quantify behaviour. Accelerometers are increasingly used in behavioural research, however validation of accelerometer readouts to enable classification of discrete behaviours is required for each species. Pangolins are a heavily trafficked clade of mammals, all of which are considered vulnerable to extinction. They are also under-researched, with little known about their behaviour in the wild. In this study, we present the first validation of behavioural classification based on accelerometer readouts for a pangolin species; the ground pangolin (Smutsia temminckii). Results: We present a standardised protocol for attaching accelerometers to pangolins to minimise the impact of devices on welfare. We match the readouts from accelerometers to behaviours defined through video observations. Using a random forest classification, we defined five discrete behaviours (walking, digging, feeding, investigating ground, and stationary, accuracy of 85%) and three activity levels (low, medium, and high, accuracy of 94%) from accelerometer readouts. We determine optimal sampling frequency and window length (50 Hz and five seconds for discrete behaviour, 10 Hz and seven seconds for activity level). We then deploy accelerometers and classify the behaviour of three free-ranging pangolins for between two and four days. We find considerable variation in peak daily activity between free-ranging pangolins with different individuals displaying nocturnal and crepuscular behaviour. We also find that pangolins spend the majority of their time (between 62 and 71%) at rest. Conclusion: The methods we present will enable the quantification of ground pangolin behaviour in the wild to improve our understanding of the species' ecology and help inform conservation efforts. This will also help to improve our fundamental understanding of animal behaviour and ecology. [ABSTRACT FROM AUTHOR]

Conservation monitoring is paramount for the gathering of information on species and populations in need of conservation actions. However, monitoring of the mountain bongo Tragelaphus eurycerus isaaci , a Critically Endangered antelope endemic to Kenya, has hitherto been limited to surveillance (i.e. focused on persistence of the species in particular areas), thus limiting the information that could be retrieved on the status and trends of these populations. Using a newly developed identification system, we implemented robust design mark–recapture using existing camera-trap records of four wild subpopulations of the bongo. We provide data on sex and age structure and the first estimates of population size in the wild. Males and calves seem to be suffering higher mortality than females, and only two of the four monitored populations include adults of both sexes and calves. The combined size of these two breeding populations is estimated to be 29–50. Our findings confirm the critical situation of the mountain bongo in the wild and highlight the need for conservation actions to reinforce the wild populations for the long-term conservation of this antelope. [ABSTRACT FROM AUTHOR]

The European Roller Coracias garrulus has suffered greatly from breeding habitat loss due to the renovation of old farmhouses and rural buildings and changing agricultural practices that took place extensively across Europe in the last decades. As a consequence, this species experienced a significant decline, and local extinctions of breeding populations were recorded in several European countries. We investigated nest sites and nesting area selection by the Italian Roller population during the breeding period (May–August) between 2016 and 2018. We collected 711 points from field surveys and used four types of point pattern analysis to detect space-time patterns of nest site and nesting area selection. We found that: (a) the spatial distribution of selected (i.e., occupied) nest sites was significantly nonrandom (p < 0.01) for all years and months; (b) only 2.6% of the selected nest sites was located within parks or reserves; (c) there were significant (p < 0.01) latitudinal, longitudinal, and altitudinal shifts of selected nest sites between May and August; (d) the geographical barycentres of selected nest sites shifted northward by about 80 km per month from May (southernmost barycentre) to August (northernmost barycentre); (e) four main nesting areas (7886 km2 in total) occurred in central and southern Italy, whose utilization by the European Rollers differed between months but not between years; (f) the detected nesting areas corresponded mainly to non-irrigated arable lands (41.22% of their extent) and natural grasslands (12.80%). Our results are useful to support conservation strategies for the breeding sites of this farmland species, which is not a regular visitor to protected areas in Italy. [ABSTRACT FROM AUTHOR]

In order to explore the effective monitoring method of the main agricultural pest Ostrinia furnacalis, the field population of Ostrinia furnacalis in Luohe of Henan Province was monitored and the population dynamics was analyzed by using the catchers with forecasting lamp, search light or sex attractant in 2022 and 2023. The results showed that the catchers with forecasting lamp, search light or sex attractant could all trap Ostrinia furnacalis adults. In 2022 and 2023, the number of pests trapped by the catchers with forecasting lamp was 6767 and 3854, respectively, and the number of pests trapped by the catchers with search light was 6019 and 9666, respectively. The population fluctuation dynamics of Ostrinia furnacalis adults under the two kinds of lights both showed two obvious peaks, which were both from the middle ten days of May to the first ten days of June and from the first ten days of August to the middle ten days of September. Among them, the number of pests in the first peak period accounted for 6.60%−26.60% of the total number of trapped pests in the year. The number of trapped pests in the second peak period was more, accounting for 64.22%−90.58% of the total number of trapped pests in the year. There were multiple peaks in this period, and the highest number of trapped pests per day appeared in the first ten days of September. In 2023, the number of pests trapped by the catcher with sex attractant was 252.67, which was significantly lower than that trapped by the catcher with light in the same period, but there was a significant peak of trapping pests from the middle ten days of May to the first ten days of June. In 2023, the beginning date of seeing Ostrinia furnacalis under the three trapping methods was in mid-April, and the end date of seeing Ostrinia furnacalis with sexual trapping (the last ten days of September) was earlier than that with light trapping (the middle and last ten days of October). The results of this study could provide reference for the prediction and green prevention and control of Ostrinia furnacalis. [ABSTRACT FROM AUTHOR]

Tigers and other large predatory carnivores have suffered population extirpations and range contractions. This is particularly true for tiger populations in southeastern Asia, which harbours one-third of their remaining habitats. In stark contrast, a sustained recovery of a wild tiger population has occurred between 2007 and 2023, in three reserves of Thailand: Huai Kha Khaeng (HKK), Thung Yai East (TYE) and Thung Yai West (TYW), which together cover 6470 km2 (36%) of the larger Western Forest Complex (WEFCOM). We quantitatively monitored this recovery employing closed and open model analyses of data from photographic capture-recapture sampling. The resulting estimates of tiger population dynamic parameters showed: mean (±SE) tiger abundance annually varied from 36 (1.0) to 79 (1.53) in HKK, 2 (0.26) to 20 (4.45) in TYE and 3 (0.26) to 44 (2.11) in TYW, driven by mean annual survival rates of 0.79 (0.02) in HKK, 0.72 (0.05) in TYE, and 0.69 (0.05) in TYW. The annual numbers of recruits fluctuated from 0 (1.69) to 33 (1.93) tigers in HKK, 0 (0.47) to 13 (0.57) in TYE and 0 (1.13) to 36 (2.28) in TYW. Overall, the mean tiger population densities/100 km2 ranged between 1.3 (0.19) and 2.9 (0.29) in HKK, 0.2 (0.08) and 1.8 (0.34) in TYE, and 0.2 (0.07) and 3.1 (0.56) in TYW. Generally, the tiger population trended upward, with reserves protected over longer periods leading the tiger recovery. Our results are further backed by ancillary records on births of 67 cubs, 47 tiger dispersal events, as well as the recovery corresponding with incremental spatio-temporal coverage by the patrols. Cumulatively, our results provide evidence that effective law enforcement should be a critical component for achieving tiger population recoveries in Asia. Alternative conservation strategies that ignore this component do not appear to be evidence-based. Our results also demonstrate the utility of the independent collaborative monitoring framework adopted by the Thailand Government.

The Mediterranean flora is characterized by a high number of narrow endemic plant species that are often restricted to a few small populations. One of these species, Valeriana amazonum, a perennial plant occurring only in the Supramontes region of central eastern Sardinia, is categorized as Critically Endangered on the IUCN Red List because of its restricted range, small population size and an inferred decline caused by several threats. During 2007–2022, we monitored all mature individuals of this plant annually and surveyed ecologically suitable sites for the species. We identified two previously unknown populations and also learnt of two successful translocations carried out independently by an unknown local citizen. As our monitoring data indicate there has been no decline in the number of mature individuals over the period of monitoring, the species’ conservation status requires reassessment. We recommend that V. amazonum should be recategorized as Near Threatened as it seems to be poorly known rather than highly threatened. This could also be the case with other narrow Mediterranean endemics, especially those that grow in inaccessible habitats for which long-term studies are needed to assess conservation status.

Abstract The Mediterranean fruit fly (medfly) (Ceratitis capitata, Diptera: Tephritidae), is an extremely polyphagous pest that threatens the fruit production and trading industry worldwide. Monitoring C. capitata populations and analysing its dynamics and phenology is considered of outmost importance for designing and implementing sound management approaches. The aim of this study was to investigate the factors regulating the population dynamics of the C. capitata in a coastal and semi-mountainous area. We focused on effects of topography (e.g. elevation), host presence and seasonal patterns of ripening on the phenological patterns considering data collected in 2008. The experimental area is characterized by mixed fruit orchards, and Mediterranean climate with mild winters. Two trap types were used for population monitoring. The female targeted McPhail type and the male targeted Jackson type. Traps were placed in farms located at different elevations and landscape morphology (coastal and semi-mountainous areas). The main crops included citrus, apples, peaches, plums, pears, figs, quinces and apricots. Adult captures were first recorded in May, peaked in mid-summer and mid-autumn and almost ceased at the end of the season (January 2008). Captures in the coastal areas preceded that of highlands by 15 days. Most of the adults detected during the fruit ripening of late stone fruit cultivars (first peak) and citrus (second peak). The probability of capturing the first adults preceded almost three weeks the peak of adult captures either considering the elevation or host focus analyses. The results provide valuable information on the seasonal population trend of C. capitata in mixed fruit Mediterranean orchards and can support the set-up of IPM systems in areas with various landscapes and different hosts throughout the fruit growing season.

Simple Summary: The Calabar angwantibo is a mammal species found only in southeastern Nigeria and southwestern Cameroon. This study tried to assess the abundance and density of this species in the Oban Hills Region of Nigeria. Our results showed that the species has an estimated population of 4456 individuals with an estimated density of 1.56 animals/km2 in the study area. Our research underlines the significance of species monitoring and provides valuable insight into the Calabar angwantibo's population in rainforest ecosystem of Oban Hills Region. Population abundance and density estimates play important roles in biodiversity conservation assessment and can lead to prioritization of conservation efforts, strategies, and management. The Calabar angwantibo (Arctocebus calabarensis) is a poorly studied, Near-Threatened nocturnal, arboreal mammal species occurring only in the lowland moist tropical rainforest blocks of southeastern Nigeria and southwestern Cameroon. Like other arboreal nocturnal mammals, there are gaps in knowledge of the distribution and abundance of this species, which may be facing population declines due to habitat loss and hunting. In this study, we investigated the abundance and density of A. calabarensis in the Oban Hills Region of Nigeria. We conducted systematic distance sampling survey along 32 transects in different habitats in a 1227 km of survey efforts. A total of 41 sightings of A. calabarensis were detected, resulting in an abundance of 7345 individuals (95% CI = 1.51–4.37) with an estimated density of 2.57 animals/km2. The estimated population abundance is 6515 individuals in closed-canopy forests and 830 individuals in secondary forests, with encounter rates of 0.52 individual/km2 and 0.60 individuals/km2 in the closed canopy and secondary forest habitats. The global estimates encounter rate of A. calabarensis across the habitat types is 0.33 individuals/km2 and population abundance of 4456 individuals. Our findings indicate that the A. calabarensis populations can adapt to low changes in forest habitat modifications resulting from increasing and widespread forest disturbance by human-dominated activity, which is giving way to forest clearance for agriculture cultivation and infrastructural development. Our findings help to fill a knowledge gap regarding this species and may help establish a baseline for future management, population monitoring, and conservation of the cryptic population of A. calabarensis in Cross-Sanaga Forests. [ABSTRACT FROM AUTHOR]

The Mediterranean flora is characterized by a high number of narrow endemic plant species that are often restricted to a few small populations. One of these species, Valeriana amazonum , a perennial plant occurring only in the Supramontes region of central eastern Sardinia, is categorized as Critically Endangered on the IUCN Red List because of its restricted range, small population size and an inferred decline caused by several threats. During 2007–2022, we monitored all mature individuals of this plant annually and surveyed ecologically suitable sites for the species. We identified two previously unknown populations and also learnt of two successful translocations carried out independently by an unknown local citizen. As our monitoring data indicate there has been no decline in the number of mature individuals over the period of monitoring, the species' conservation status requires reassessment. We recommend that V. amazonum should be recategorized as Near Threatened as it seems to be poorly known rather than highly threatened. This could also be the case with other narrow Mediterranean endemics, especially those that grow in inaccessible habitats for which long-term studies are needed to assess conservation status. [ABSTRACT FROM AUTHOR]

Widely dispersed fragmented populations are a challenge to monitor because subpopulation sizes may be very small, difficult to access and time consuming to sample regularly. We use the coconut crab (Birgus latro) on Pemba, United Republic of Zanzibar as a case study for estimating highly fragmented populations and metapopulation sizes. The species is a very large terrestrial decapod threatened by exploitation and habitat alteration and now classified as vulnerable. We developed an integrated model to analyse capture‐mark‐recapture (CMR) data from five sites jointly with count data from 24 sites to estimate site‐level densities and population sizes, predicted total population size across the Pemba archipelago, and investigated the effect of six predictors of human influence on density. We fitted separate models to test the effect of the same predictors on raw counts and individual body mass. We estimate the total population of coconut crabs on the Pemba archipelago to be c. 6700 terrestrial individuals. We show that government protection generally affects crabs positively, whereas presence of agriculture negatively affects their densities. This study highlights that time‐consuming CMR data can be leveraged to estimate densities on less visited sites, and that fully protected islands are critical for maintaining relatively high population densities. Our overall population estimate suggests that Pemba still hosts a viable coconut crab population in a part of its range where the species is otherwise in steep decline. [ABSTRACT FROM AUTHOR]

Feral swine were targeted for and successfully eradicated from Saint Vincent Island (SVI), a National Wildlife Refuge (NWR) along the coast of Florida's panhandle to protect its habitats and uncharacteristically high diversity of wildlife species for barrier islands in the region, including federal and state-listed threatened and endangered species. The eradication effort was initiated in early 2015 and concluded in 2019. A total of 438 feral swine were removed from the Island, 417 by federal control experts and 21 by recreational hunters. In general, the amount of effort needed to eradicate each feral swine slowly increased as the eradication effort progressed; however, effort increased by an order of magnitude in the final six months. The last three feral swine took 77 days of effort to remove. The eradication effort provided an opportunity for evaluating and comparing methods for indexing feral swine population abundance and their abilities to describe population trends and to detect animals at low population abundance. The feral swine population was monitored from 2015–2019 using a passive tracking index (PTI) twice each year and using camera traps. Camera and track plot data were used to calculate abundance indices based on a well-documented indexing paradigm applied to feral swine populations. In addition, we simultaneously monitored relative abundance of other mammalian species crucial to management for the Island. The PTI and camera index both well-tracked population abundance simultaneously for the large ungulates inhabiting the Island (feral swine, white-tailed deer, sambar deer). However, the sensitivity for the PTI to capture animal observations was much greater than for the camera stations. This held true even over 5-day observation sessions by cameras versus 3-day observation sessions for track plots. Additionally, the PTI was sensitive for simultaneously capturing data for smaller animals, raccoons and armadillos, whereas the camera stations were ineffective for the smaller species, likely due to camera positions being optimised to capture feral swine. Our 100-m track plots outperformed the camera stations in many regards, but the camera stations required less labour in the field and were less fragile in the field, especially from weather or access issues. In 2018, Hurricane Michael, a category 5 hurricane, struck SVI. Its habitat damage may have adversely impacted white-tailed deer and sambar deer populations, but not armadillos or raccoons. Both the swine eradication and hurricane impacts provided valuable means for validating indexing procedures. [ABSTRACT FROM AUTHOR]

The breeding period is a demanding and time-constrained phase for migratory bird species. Breeding outcome and duration can interact with the extent and duration of post-breeding movements, resulting in individual differences in space use ultimately influencing later stages of the annual cycle. We present space-use and home range estimates during the breeding season for 21 European rollers Coracias garrulus tracked between 2018 and 2022, in Italy and Croatia. Using high-resolution spatial GPS data coupled with regular nest-box monitoring, we analyzed differences in space use during the incubation/nestling period versus post-breeding period prior to migration, accounting for the breeding outcome (successful vs. failure). We found that adult movements were strongly reduced during the first phase, whereas increased in the post-breeding phase, especially for failed breeders. Successful breeders remained in the surroundings of the nest site, whereas unsuccessful ones tended to abandon the nest and visit distant areas (up to 500 km) for long periods (60.5 ± 6.2 days). Breeding outcome did not influence the departure date of autumn migration, suggesting that failed breeders used this period for exploratory movements but not for advancing the onset of migration. Such exploratory movements may be functional to prospect and inform settlement decisions in failed breeders in search of new breeding opportunities and may be particularly important in migratory species, which generally have a limited period to gather information prior to autumn migration. The study demonstrates the need to investigate seasonal movements in different populations and the potential importance of prospecting post-breeding movements for long-distance migratory species. [ABSTRACT FROM AUTHOR]

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Context: Masked water snakes (Homalopsis buccata , Homalopsidae) thrive in the muddy edges of agricultural ponds and canals in densely populated areas of West Java, Indonesia, and are harvested by local farmers to protect fish stocks and to provide meat, skins, and medicines for commercial use. Aims: Here, we aimed to quantify sexual dimorphism and reproductive biology of H. buccata , so as to deepen our knowledge of the species' inherent ability to withstand commercial harvests. Methods: We examined carcasses of 4286 snakes at six processing sites to quantify biological attributes (e.g. sexual dimorphism in body size and shape, seasonality of reproduction, fecundity, reproductive frequency), with emphasis on traits that affect the ability of snake populations to withstand this intensive harvesting. Key results: The snakes we examined were primarily adults (<1% juvenile), with approximately equal numbers of males and females except in January (when females comprised >90% of specimens). Females grow larger than males, and they are more heavy-bodied but shorter-tailed than are males of the same snout–vent length. Reproduction is seasonal in both sexes, with testis volumes decreasing to a minimum over the period August to November (late dry season) when most adult-size females were gravid. Litter sizes ranged from 1 to 37 (mean 12), increasing with maternal body size, with ~75% of females reproducing each year. Conclusions: On the basis of these results, we infer that the life history of H. buccata (viviparity, high fecundity, frequent reproduction, rapid maturation) renders it inherently resilient to harvesting, especially because that offtake is based on males as well as females. Because a lack of sustainability is evident only in hindsight, regular monitoring of the trade could assure that any problems are detected rapidly. Implications: To further buffer these populations from the impact of harvest, hunting could be restricted during January (a time when gravid females are disproportionately vulnerable) and the largest snakes (females, with high fecundity and reproductive frequency) could be excluded from harvests. Although it is impossible to prove sustainability of any wildlife harvest, except in hindsight, studies of commercially exploited taxa can provide a basis for prediction. Our data on commercially harvested masked water snakes in Java, Indonesia, suggest that these snakes possess ecological and life-history attributes likely to make them resilient to harvesting, consistent with the species' continuing abundance, despite a long history of intense exploitation. Photograph by Alamsyah Herlambang. [ABSTRACT FROM AUTHOR]

Mountainous regions are very vulnerable to climate changes, as they experience higher temperature increases than the surrounding environments. A general movement of species toward higher altitudes, in search of suitable sites, is being observed. In the case of the Italian Alps, an expansion of the brown hare (Lepus europaeus) is possible within the zones occupied by the mountain hare (Lepus timidus), which frequents higher altitudes. The risk is an increase in the hybridization and a contraction of the mountain hare’s range. In this study, we analyzed the hunting bags (weighted by the number of active hunters each year) of brown and mountain hares from the period of 1980–2020, in the province of Sondrio (Central Alps) in northern Lombardy (N-Italy), with the aim of (i) highlighting any population trends in relation to climate change, (ii) identifying altitudinal changes in the distribution of the two species over the years, (iii) identifying the environmental variables that influence the distribution of the two species, and (iv) creating suitability maps in the study area. To study population trends, the hunting bag data were corrected by dividing the number of hare shot by the number of active hunters in that year. For both species, no population trends were found between 1980 and 2020. Weather variables do not seem to have influenced population trends. No significant trends in the altitudinal distribution of the two species were observed over the period investigated. The results indicate that the two species select different altitudes, with the exception of the belt between 1600 and 1800 m a.s.l. Both species select meadows. [ABSTRACT FROM AUTHOR]

Anthropogenic activities generate increasing disturbance in wildlife especially in extreme environments where species have to cope with rapid environmental changes. In Antarctica, while studies on human disturbance have mostly focused on stress response through physiological and behavioral changes, local variability in population dynamics has been addressed more scarcely. In addition, the mechanisms by which breeding communities are affected around research stations remain unclear. Our study aims at pointing out the fine-scale impact of human infrastructures on the spatial variability in Adélie penguin (Pygoscelis adeliae) colonies dynamics. Taking 24 years of population monitoring, we modeled colony breeding success and growth rate in response to both anthropic and land-based environmental variables. Building density around colonies was the second most important variable explaining spatial variability in breeding success after distance from skua nests, the main predators of penguins on land. Building density was positively associated with penguins breeding success. We discuss how buildings may protect penguins from avian predation and environmental conditions. The drivers of colony growth rate included topographical variables and the distance to human infrastructures. A strong correlation between 1-year lagged growth rate and colony breeding success was coherent with the use of public information by penguins to select their initial breeding site. Overall, our study brings new insights about the relative contribution and ecological implications of human presence on the local population dynamics of a sentinel species in Antarctica. [ABSTRACT FROM AUTHOR]

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

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Passive integrated transponder (PIT) telemetry is commonly used to monitor fish movements and behavior. To reduce inferential bias in PIT telemetry studies, it is important to quantify the effects of tagging procedures on fish survival. To this end, we conducted a controlled experiment to test the hypothesis that intraperitoneal injection of 23‐mm PIT tags would have no effect on the survival of adult Blueback Herring Alosa aestivalis. Methods: We compared mortality rates of tagged and untagged Blueback Herring (n = 174; size range 202–277 cm) that were retained in experimental tanks for 14 days. Result: We observed no difference in the probability of survival between tagged (50% survival) and untagged (42%) groups. Conclusion: These results suggest that intraperitoneal tag injection is a safe and effective method of PIT tagging adult Blueback Herring and supports the use of this technique in field telemetry studies. Impact statementWhile PIT telemetry is frequently used to monitor fish movements and behavior, few studies have evaluated the effect of tagging procedures on fish survival. By comparing the survival of control and treatment groups retained in experimental tanks for 14 days, this study found that intraperitoneal injection of 23‐mm PIT tags had a negligible effect on the survival of Blueback Herring. [ABSTRACT FROM AUTHOR]

Introduction: Diadromous fish populations have strongly declined over decades, and many species are protected through national and international regulations. They account for less than 1% of fish biodiversity worldwide, but they are among the most perceptible linkages between freshwater and marine ecosystems. During their migration back and forth, diadromous fish species are subjected to many anthropogenic threats, among which river damming can severely limit access to vital freshwater habitats and jeopardize population sustainability. Here, we developed a method based on a double-observer modeling approach for estimating the abundance of diadromous fish during their migration in rivers. Methods: The method relies on two independent and synchronous records of fish counts that were analyzed jointly thanks to a hierarchical Bayesian model to estimate detection efficiencies and daily fish passage. We used simulated data to test model robustness and identify conditions under which the developed approach can be used. The approach was then applied to empirical data to estimate the annual silver eel run in the Touques River, France. Results: The analysis of simulated datasets and the study case gives evidence that the model can provide robust,accurate, and precise estimates of detection probabilities and total fish abundance in a set of conditions dependent on the information provided in the data (annual distribution of fish passage, annual number of observation, pairing period, etc.). Discussion: Then, the method can be applied to various species and counting systems, including nomad acoustic camera devices. We discuss its relevance for programs on river continuity restoration, notably to quantify population restoration associated with dam removals. [ABSTRACT FROM AUTHOR]

Because healthy psychosocial development in the first years of life is critical to lifelong well‐being, governmental, and nongovernmental organizations are increasingly interested in monitoring psychosocial behaviors among populations of children. In response, the World Health Organization is developing the Global Scales of Early Development Psychosocial Form (GSED PF) to facilitate population‐level psychosocial monitoring. Once validated, the GSED PF will be an open‐access, caregiver‐reported measure of children's psychosocial behaviors that is appropriate for infants and young children. This study examines the psychometric validity evidence from 45 items under consideration for inclusion in the GSED PF. Using data from N = 836 Nebraskan (USA) children aged 180 days to 71 months, results indicate that scores from 44 of the 45 (98%) items exhibit positive evidence of validity and reliability. A bifactor model with one general factor and five specific factors best fit the data, exhibited strong reliability, and acceptable model fit. Criterion associations with known predictors of children's psychosocial behaviors were in the expected direction. These findings suggest that measurement of children's psychosocial behaviors may be feasible, at least in the United States. Data from more culturally and linguistically diverse settings is needed to assess these items for global monitoring. [ABSTRACT FROM AUTHOR]

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

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

Capercaillie Tetrao urogallus abundance was estimated from genetic and field methods in a forest in Strathspey, Scotland. Genetic methods prior to application of capture-mark-recapture techniques over-represented males by 6–15% relative to lek attendance, gave contrasting results between years relative to males seen on brood counts, and under-represented females by 82% and 173% at leks and on brood counts, respectively. A CMR genetic-based model for males only estimated about twice as many males as on lek or brood counts. Of the 33 males identified by genetic methods in 2014, only four (12%) were detected 2 years later. We conclude that our genetic sampling effort needed doubling to provide accurate population estimates. [ABSTRACT FROM AUTHOR]

The leafhopper, Orosanga japonicus )Melichar( upon sucking sap from the plant deposits a lot of honeydew on the leaves, attracts sooty mold, and blackens the leaves, fruits and branches. The use of monitoring and control methods is an urgent need because of lack of knowledge on the behavior of O. japonicus. Therefore, during the years 2021 and 2022, the attraction of this leafhopper was investigated to the sticky cards with various colors including white, yellow, red, blue, and green. Similarly, the light traps equipped with energy-efficient lamps of different spectrums such as UV, white, yellow, red, and green light was also considered for this investigation. The experiments were performed from the onset up to the end of this insect’s activity in citrus orchards. According to the results, O. japonicus adults were attracted and captured mostly by the UV light traps with means of 1437.3±89.7 and 299.6±18.2 in the first and second years of survey, respectively in comparison with other lamp colors used. On the other hand, the attraction of the leafhopper to the cards showed that the white and blue cards attracted more insects with means of 24.5±5.3 and 17.1±2.1 respectively in two-year of survey, compared to green, red, and yellow cards used. This preliminary information on population monitoring of this pest may pave the path for future management of O. japonicus. [ABSTRACT FROM AUTHOR]

Single Nucleotide Polymorphisms (SNPs) are variations that occur at single nucleotides in the genome and are present at an appreciable level in a population. SNPs can be linked to phenotypes of interest, for example diseases, recent adaptations, or species hybridization. They can also be used to study phylogeny and evolutionary history. Technologies that rapidly identify and catalog the presence of SNPs in a DNA sample are known as SNP genotyping panels, and they continue to undergo rapid development. Such methods have great utility across the agricultural sciences in diverse areas such as plant and animal breeding, pathogen and pesticide resistance identification, outbreak tracing, and hybridization detection. Here, we provide an overview of 14 different SNP genotyping technologies and weigh some of the pros and cons associated with each platform. This review is not comprehensive or technical, nor does it aim to be. Rather, the objective is to provide an introduction to the landscape of genotyping technologies for researchers who do not have experience with these methods. Three classes of SNP genotyping methods are Polymerase Chain Reaction (PCR)-based (nine different methods), microarray-based (one method), and Next-Generation Sequencing (NGS)-based (four different methods). We discuss how each genotyping class is suited for different niches; PCR-based has a low SNP count and high sample number, microarray-based has a very high SNP count and a moderate sample number, and Next-Generation Sequencing-based has a moderate SNP count and moderate number of samples. Included are basics about how the methods function and example use cases of each method. Additionally, we introduce and discuss the potential for the MinION sequencer in SNP genotyping. For each technology, we provide insights into cost, equipment needs, labor costs, experimental complexity, data output complexity, and accessibility. These considerations address the feasibility of deploying the technologies in an agricultural science environment. [ABSTRACT FROM AUTHOR]

Geoffroy’s spider monkeys, an endangered, fast-moving arboreal primate species with a large home range and a high degree of fission–fusion dynamics, are challenging to survey in their natural habitats. Our objective was to evaluate how different flight parameters affect the detectability of spider monkeys in videos recorded by a drone equipped with a thermal infrared camera and examine the level of agreement between coders. We used generalized linear mixed models to evaluate the impact of flight speed (2, 4, 6 m/s), flight height (40, 50 m above ground level), and camera angle (−45°, −90°) on spider monkey counts in a closed-canopy forest in the Yucatan Peninsula, Mexico. Our results indicate that none of the three flight parameters affected the number of detected spider monkeys. Agreement between coders was “substantial” (Fleiss’ kappa coefficient = 0.61–0.80) in most cases for high thermal-contrast zones. Our study contributes to the development of standardized flight protocols, which are essential to obtain accurate data on the presence and abundance of wild populations. Based on our results, we recommend performing drone surveys for spider monkeys and other medium-sized arboreal mammals with a small commercial drone at a 4 m/s speed, 15 m above canopy height, and with a −90° camera angle. However, these recommendations may vary depending on the size and noise level produced by the drone model.