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Simple Summary: In this study, we investigated the population size of Amur softshell turtles (Pelodiscus maackii) around Jewellery Island, a river island in the mid-stream of the Ussuri River using continuous-time capture–recapture methods, and analyzed the spatial distribution of Amur softshell turtles based on cage trapping results. The results revealed the disturbingly low population density of Amur softshell turtle in this area, highlighting the urgent need for targeted conservation efforts. Our spatial distribution study indicates that juvenile turtles predominantly inhabit still-water channels and vegetated shoreline areas, emphasizing the critical importance of these habitats. This study establishes a foundational framework for future population assessments and pinpoints vital conservation areas. Our results fill a gap in the knowledge of the natural history of this endangered species. Freshwater turtle species preservation relies on understanding their population dynamics and geographical distribution. Amur softshell turtles (ASTs [Pelodiscus maackii]) are poorly protected due to insufficient awareness and the population in Northeastern China has experienced a steep decline compared to previous years. This study aims to investigate the population density and structure of ASTs in the Jewellery Island area of the Ussuri River in Northeast China using continuous-time capture–recapture methods in closed populations. A three-month mark–recapture study was conducted in 2022, resulting in 35 juvenile captures, including 12 recaptures from 23 marked individuals. The estimated population size in the study area was 40.79 ± 9.75 (95% confidence interval, 95% CI = 27–65), translating to 0.663 ± 0.158 turtles/ha (95% CI = 0.44–1.06 individuals/ha). Approximately 35.4–85.2% of the estimated population was marked. Additionally, we explored the influence of environmental variables on turtle distribution by dividing the surveyed sites into seven sections based on their natural characteristics. The ASTs distribution inferred from trapping successes was considerably different among sections, with most turtles (91%) captured at the vegetated shoreline and in water channel 2. This research offers essential baseline data to support future assessments of ASTs population on a larger scale and to inform the development of conservation strategies. [ABSTRACT FROM AUTHOR]

The majority of attempts to enumerate the homeless population rely on point-in-time or shelter counts, which can be costly and inaccurate. As an alternative, we use electronic health records from the Vancouver Island Health Authority, British Columbia, Canada from 2013 to 2022 to identify adults contending with homelessness based on their self-reported housing status. We estimate the annual population size of this population using a flexible open-population capture–recapture model that takes into account (1) the age and gender structure of the population, including aging across detection occasions, (2) annual recruitment into the population, (3) behavioural-response, and (4) apparent survival in the population, including emigration and incorporating known deaths. With this model, we demonstrate how to perform model selection for the inclusion of covariates. We then compare our estimates of annual population size with reported point-in-time counts of homeless populations on Vancouver Island over the same time period, and find that using data extracts from electronic health records gives comparable estimates. We find similarly comparable results using only a subset of interaction data, when using only ER interactions, suggesting that even if cross-continuum data is not available, reasonable estimates of population size can still be found using our method. [ABSTRACT FROM AUTHOR]

Revealing the demographic structure of past societies forms the basis of archaeological demography and paleodemography studies. Archaeological demography is a field of study that examines the demographic structure and dynamics of past human societies in line with the traces of human activities and the remains of material culture in archaeological records. Research in this field is interdisciplinary and includes findings from fields such as anthropology, palaeogenetics and human ecology. Archaeological demography seeks answers to questions such as the development of methods for determining the demographic structure of past societies, the timing of the emergence of modern human demographic systems, demographic transitions, colonisation and demographic extinctions. Archaeological evidence, such as the size of settlements, the use and consumption of materials and artefacts, and quantities of waste, are traditional indicators used to estimate population size and density in the past. This evidence has been combined in recent years with an increasing number of data sets, supported by radiocarbon dating programmes. These datasets are being used to examine waves of demographic progress during periods of continental-wide colonisation and cultural change, and to detect periods of population decline, extinction and stagnation throughout settlement history. Palaeodemographic studies, which deal with the birth and death statistics of prehistoric and protohistoric societies, examine the skeletal remains of societies that lived in different times and places. The data obtained are evaluated together with the grave finds and cultural remains of those societies. Archaeological demography and paleodemography studies carried out to reveal the demographic structures of Anatolian societies, if supported by paleopathological, paleobotanical and paleoecological information, will provide clearer data on the biological and cultural changes that have occurred throughout human history. The aim of this article is to provide information about the methods of archaeological demography and paleodemographic research and to reveal the demographic structures of Anatolian societies in the light of this information. [ABSTRACT FROM AUTHOR]

Genome streamlining, i.e. genome size reduction, is observed in bacteria with very different life traits, including endosymbiotic bacteria and several marine bacteria, raising the question of its evolutionary origin. None of the hypotheses proposed in the literature is firmly established, mainly due to the many confounding factors related to the diverse habitats of species with streamlined genomes. Computational models may help overcome these difficulties and rigorously test hypotheses. In this work, we used Aevol, a platform designed to study the evolution of genome architecture, to test 2 main hypotheses: that an increase in population size (N) or mutation rate (μ) could cause genome reduction. In our experiments, both conditions lead to streamlining but have very different resulting genome structures. Under increased population sizes, genomes lose a significant fraction of noncoding sequences but maintain their coding size, resulting in densely packed genomes (akin to streamlined marine bacteria genomes). By contrast, under an increased mutation rate, genomes lose both coding and noncoding sequences (akin to endosymbiotic bacteria genomes). Hence, both factors lead to an overall reduction in genome size, but the coding density of the genome appears to be determined by N × μ ⁠. Thus, a broad range of genome size and density can be achieved by different combinations of N and μ. Our results suggest that genome size and coding density are determined by the interplay between selection for phenotypic adaptation and selection for robustness. [ABSTRACT FROM AUTHOR]

Assisted gene flow can restore genetic diversity when genetic drift has driven deleterious alleles to high frequencies in small, isolated populations. Previous crosses among 20 populations of Gymnadenia conopsea documented the strongest heterosis and the weakest inbreeding depression in sparse and small populations, consistent with fixation of mildly deleterious alleles by genetic drift. We genotyped the populations used for crosses, and used 1200–1728 SNPs to test the following predictions: (1) heterosis increases with genetic differentiation (FST) to donor populations and decreases with genetic diversity in the recipient population, (2) inbreeding depression increases with genetic diversity, and (3) genetic diversity increases, and mean FST to other populations decreases, with population size and density. Pairwise FST ranged from very low to moderate (0.005–0.20) and genetic diversity varied moderately among populations (proportion of polymorphic loci = 0.52–0.75). However, neither FST between populations, nor genetic diversity in the recipient population, were related to the strength of heterosis. There was also no association between genetic diversity and the strength of inbreeding depression. Genetic diversity increased and mean FST decreased with population size, consistent with reduced diversity and increased differentiation of small populations by genetic drift. The results indicate that the loci conferring heterosis are not mirrored by overall population differentiation, and limited additional information on potential source populations for genetic rescue is gained by the genetic data. Instead, the use of controlled crosses can directly reveal positive effects of introducing new genetic material, and is a simple method with high potential in conservation. [ABSTRACT FROM AUTHOR]

The article discusses the impact of population size, structure, fertilization success, and propagule dimorphism on sex allocation in simultaneous hermaphrodites, focusing on plant reproduction. The authors present a mathematical model that challenges classical sex allocation theory by showing that population size, pollen mortality, and fertilization success can influence sex allocation. The study reanalyzes the model and confirms the classical result of equal sex allocation under panmixia. The research highlights the importance of considering population structure and dispersal rates in understanding sex allocation evolution. [Extracted from the article]

A global, accurate estimation of the Southern Gelada (Theropithecus gelada obscurus, Heuglin 1863) population is poorly available. This study aimed to investigate the population size and structure of the Southern Gelada in the Abune Yosef Zigit Community Conservation Area. Population counts were done at six counting blocks covering both the dry and wet seasons in 2021. The total mean population size of the Southern Gelada in Abune Yosef Zigit Community Conservation Area was 929 (±8.46). The population comprised 9% (82±0.92) adult males, 34% (314±3.47) adult females, 11% (99 ±1.23) sub-adult males, 10% (95±1.30) sub-adult females, 24% (128±1.92) juveniles, and 13% (121±1.73) infants. However, all age groups of Southern Gelada showed insignificant seasonal variation in abundance, except for infants (P = 0.027). The mean age and sex ratio of males to females (χ² = 89.97, P ≤ 0.05), adult males to adult females (1:4.18, χ² = 135.92, P ≤ 0.05), and infants to adult females (1:3.04, χ² = 85.63, P ≤ 0.05), varied significantly between seasons. These age and sex ratios also exhibited notable differences between the dry and wet seasons in the area (P ≤ 0.05). Geladas exist in social groups ranging from the basic all-male unit (10.37 ±1.04) to complicated social bands (157.58±5.84). The population estimate is crucial and contributes to an accurate global population estimate and, consequently, better conservation of the species. [ABSTRACT FROM AUTHOR]

Limited water availability, population growth, and increasing water demand have resulted in freshwater crises in many countries, including China. In this paper, the water resource‐carrying capacity (WRCC) model simulated the trajectory of China's various systems, representing interactions among humans, water resources, and economics, among others. The results indicated that, at the national level, 700 billion m3 of available freshwater could support population sizes of 2.12, 1.96, and 1.85 billion, along with economic sizes of $40.65, $34.08, and $29.21 trillion, under high‐, moderate‐, and low‐development scenarios, respectively. And it also showed the population and economic size of each province across China under high‐, moderate‐, and low‐development scenarios. This study's WRCC‐based simulations can provide guidance for future policies related to water, population, and economics. Overall, contributions of this study include (1) a quantitative model related to freshwater security and water policies; (2) the model narratives that paint a better picture of China's future water security and socioeconomic development; (3) the conclusion that it is conducive to adjust water use rigid constraints with water policies; (4) an understanding that it is more intuitive to use population size and economic scale instead of dimensionless scores to characterize the state of WRCC. The WRCC model is instructive for the other counties or regions. [ABSTRACT FROM AUTHOR]

Any socio-economic processes occurring in the country and world have an impact on the standard of living of the population. There are many indicators that determine the standard of living of citizens, among which we can highlight the income of people as the main component of their financial well-being. In a period of global political and economic upheavals, the relevance of the topic of human quality of life is beyond doubt. During the economic war organised by the West against Russia, the countries participating in this war are of interest. These include New Zealand, although it is clear that due to the distance from Russia and weak economic ties between the countries, there will be no significant mutual influence of the sanctions restrictions. The study has analysed the income of the population of New Zealand over the past 10 to 15 years, considering differentiation by various categories, such as geographical location, qualification, and source of income. The analysis has showed a certain increase in the income and, accordingly, in the standard of living of the country’s population in the period under review. An insignificant impact on this indicator of restrictive measures during the COVID-19 pandemic is revealed, however, with the certain social policy of the state, fluctuations in the income of citizens during this period were hardly noticeable. Their assessment by sources has reflected the significant share of small businesses in the country’s economy, which shows a high degree of liberalisation of the national economy of the state. The analysis of the citizens’ incomes by geographic regions has revealed a significant impact of urbanisation on the standard of living of the New Zealand’s population, which is a global trend.

Mountain environments pose challenges for accurately assessing the population size of ungulates, which may hamper confidence in using abundance estimates for decision-making. Thus, evaluations of the accuracy of methods using known-size populations are valuable. Here, we tested the accuracy of direct counts and distance sampling to assess the size of a fenced population of Iberian ibex (Capra pyrenaica) of known size. We evaluated the influence of observer expertise (beginners and experts) on the detection error of female and male ibexes and whether training improved accuracy. The ibex population comprised 18 individuals (ten males and eight females) living in a 17-ha enclosure in northeastern Spain. After 27 surveys, experts detected 16% more ibexes than beginners. Male ibexes were ~ 13% easier to detect than females, and experts were more accurate than beginners in sexing individuals. Additionally, the detection error in absolute counts was similar among beginners but different among experts (> 10%). Despite reducing detection error over subsequent surveys, under-detection was > 50% in all events (> 85% and > 67% for beginners and experts, respectively). Our data indicate a systematic underestimation of direct counts of our mountain ungulate populations and the contribution of expertise to improving accuracy. Our results show that managers assessing mountain ungulate populations for management purposes should consider alternative methods. [ABSTRACT FROM AUTHOR]

Abstract Differential Evolution (DE) stands as a potent global optimization algorithm, renowned for its application in addressing a myriad of practical engineering issues. The efficacy of DE is profoundly influenced by its control parameters and mutation strategies. In light of this, we introduce a refined DE algorithm characterized by adaptive parameters and dual mutation strategies (APDSDE). APDSDE inaugurates an adaptive switching mechanism that alternates between two innovative mutation strategies: DE/current-to-pBest-w/1 and DE/current-to-Amean-w/1. Furthermore, a novel parameter adaptation technique rooted in cosine similarity is established, with the derivation of explicit calculation formulas for both the scaling factor weight and crossover rate weight. In pursuit of optimizing convergence speed whilst preserving population diversity, a sophisticated nonlinear population size reduction method is proposed. The robustness of each algorithm is rigorously evaluated against the CEC2017 benchmark functions, with empirical evidence underscoring the superior performance of APDSDE in comparison to a host of advanced DE variants.

In this paper, we investigate the determinants of contact between citizens and Members of Parliament (MPs) in Africa by combining theories of contact developed in advanced Western democracies with theories of clientelism developed in the Global South. Based on Afrobarometer data matched with constituency‐level electoral data, we provide a first analysis of the determinants of citizen–MP contact in 32 African countries, encompassing a broad range of regime types. We find that smaller districts and single‐member districts strengthen contact across regime types, while electoral competitiveness is only positively associated with contact in more democratic settings. In line with clientelist theories of public resource access, district links to national ruling coalitions are positively associated with contact, but we find little evidence of partisan bias. Overall, we find that contact theories travel remarkably well across regions and regime types, and we caution against interpreting clientelistic contacts as harmful for democracy. [ABSTRACT FROM AUTHOR]

The western capercaillie Tetrao urogallus, hereafter capercaillie, is the largest galliform bird present in the boreal and montane forests of the Western Palearctic. Precise and accurate methods for estimating the number of individuals and/or their densities are crucial for the proper management of its free‐ranging populations. However, obtaining reliable estimates of the abundance of populations of wild species and, particularly, of birds is not a simple task. In the case of lek‐mating birds such as capercaillie, surveys are traditionally based on lek counts, that is, counts of calling males present in their mating areas: the leks. This study was carried out on the Pyrenees at six capercaillie leks where two different lek counting approaches were performed: hide‐based and walk‐based. The results were compared with those obtained from an estimate of minimum population size (MPE) derived from genotyping all faeces samples found in the lek area, and with a population size estimate derived from a genetic mark‐recapture model (N^o) of each capercaillie lek. The results of N^o were used to estimate the detection rate (D) of both lek count approaches. Our results show that traditional lek counts do not detect all male capercaillies since the detection rate was 0.34 (95% CI: 0.26–0.43) for hide‐ and 0.56 (95% CI: 0.43–0.68) for walk‐based lek counts. Our results suggest that the walk‐based lek counts were more efficient than the hide‐based ones, providing more accurate results compared to the N^o estimate. The combination of non‐invasive sampling with genetic mark‐recapture model was found to be the most reliable method for obtaining the N^o of leks given that traditional lek counts underestimate the number of capercaillie and, furthermore, can cause disturbance to the species at these sites. [ABSTRACT FROM AUTHOR]

Conservation initiatives such as the Key Biodiversity Areas (KBA) Programme use standardized criteria based on estimates of species abundance to identify critical habitats. They therefore depend on accurate estimates of population sizes for target species. It is essential that the metrics used to measure abundance at a candidate site are consistent with those used to estimate total abundance at national or global scales, because only then can it be determined whether abundance at a site meets threshold criteria. Imagery gathered by remotely piloted aircraft systems (RPAS, or drones) has rapidly become a tool for determining abundance of surface-nesting seabirds and, therefore, can assist with the designation of KBAs. However, abundance data derived from drone imagery are often in different units, such as numbers of birds or numbers of incubating adults visible on photographs, than data derived from in-person counts, which generally measure the number of nests or breeding pairs. Therefore, drone data may not be directly comparable to data that have been historically collected to estimate overall breeding-population sizes. This study considered a candidate colony of Glaucous-winged Gulls Larus glaucescens located in the Salish Sea in southwestern Canada, which has been surveyed both by drone and by traditional ground surveys. We developed a conversion factor that at least partially translates counts of incubating Glaucous-winged Gulls detected on drone imagery to an estimate of breeding pairs. Compensating for only nests without incubating adults, results suggest that numbers of incubating adults detected by drone likely represent between 63% and 84% of the total number of breeding pairs. Applying this conversion increased the population estimate for the colony and changed former conclusions about whether the site met recommended criteria for designation as a national or global KBA for Glaucous-winged Gulls. [ABSTRACT FROM AUTHOR]

The blue-tailed bee-eater (Merops philippinus) migrates from Southeast Asia and South Asia to China for breeding every year from April to July. Previous studies have indicated that the blue-tailed bee-eater prefered to nest on the bare sandy slopes with a gradient of 30° to 90°. However, in recent years, the blue-tailed bee-eater in Raoping County Guang-dong Province has been found nesting on flat and open ground. To understand the characteristics of the nests and habitat factors of the blue-tailed bee-eater's the flat-ground nesting, we conducted a survey on the population size, nest characteristics, and nesting habitat factors of the ground-nesting blue-ailed bee-eater in Raoping County, Guangdong Province from April to July 2023. The results showed that: the population size of the flat-ground nesting blue-tailed bee-eaters in Raoping Guangdong Province ranged from 128 to 224 individuals; there were statistically significant difference in length, depth, horizontal length, and inclination angle between breeding nests and abandoned nests (P ≤ 0. 005); the nests mainly faced north, east, and northwest; the breeding nests had the narrowest daily temperature range at the bottom of the nest; the average minimum distance between adjacent nests was 3. 8 meters; the degree of exposure in the nesting area was (35. 08 ± 10. 77) %. The distance from the nests to the water source was (107. 92 ± 40. 41) meters; the soil of the nesting site was sandy, with a sand content of (92. 0 ± 3. 4) %, and the soil particle size was mainly concentrated between (0. 125 ~ 0. 250) mm. The research could provide a scientific basis for the conservation of the blue-tailed bee-eater's population and habitat. [ABSTRACT FROM AUTHOR]

Habitat destruction, land conversion, and forest fragmentation over the past several decades have resulted in major declines and local extirpation of wild animal and plant species. The gray snub-nosed monkey (Rhinopithecus brelichi) is currently listed among the 25 most endangered primate species in the world, with an estimated remaining wild population of less than 400 individuals. Given the potential negative effects of small population size on genetic diversity, we investigated how factors, such as climate, inbreeding, kinship, population structure, and effective population size, have contributed to their genetic status. We extracted DNA from 307 fecal samples and analyzed microsatellite diversity, sex-identifying genes, and the mtDNA control region in 179 wild individuals. Our analyses suggest that gray snub-nosed monkeys experienced an initial population decline during the Last Glacial Maximum, some 20,000 years ago. During the past 70 years, this species experienced a second, steeper population decline, coinciding with human activities. Their current effective population size (± SD) of 675 ± 292 exceeds the remaining number of individuals in the population and has declined by 93.9%—96.7% over the past 20,000 years. Our findings highlight the need for immediate conservation and management strategies to protect this endemic and Critically Endangered primate species. [ABSTRACT FROM AUTHOR]

The size and shape of an animal's breeding territory are dynamic features influenced by multiple intrinsic and extrinsic factors and can have important implications for survival and reproduction. Quantitative studies of variation in these territory features can generate deeper insights into animal ecology and behavior. We explored the effect of age, breeding strategy, population density, and number of neighbors on the size and shape of breeding territories in an island population of Passerculus sandwichensis (Savannah Sparrow). Our dataset consisted of 407 breeding territories belonging to 225 males sampled over 11 years. We compared territory sizes to the age of the male territorial holder, the male's reproductive strategy (monogamy vs. polygyny), the number of birds in the study population (population density), and the number of immediate territorial neighbors (local density). We found substantial variation in territory size, with territories ranging over two orders of magnitude from 57 to 5,727 m2 (0.0057–0.57 ha). Older males had larger territories, polygynous males had larger territories, territories were smaller in years with higher population density, and larger territories were associated with more immediate territorial neighbors. We also found substantial variation in territory shape, from near-circular to irregularly shaped territories. Males with more neighbors had irregularly shaped territories, but shape did not vary with male age, breeding strategy, or population density. For males that lived 2 years or longer, we found strong consistent individual differences in territory size across years, but weaker individual differences in territory shape, suggesting that size has high repeatability whereas shape has low repeatability. Our work provides evidence that songbird territories are highly dynamic, and that their size and shape reflect both intrinsic factors (age and number of breeding partners) and extrinsic factors (population density and number of territorial neighbors). [ABSTRACT FROM AUTHOR]

Simple Summary: Shiqu County, in Sichuan Province, is the eastern edge of the distribution area of the kiang (Equus kiang) on the Tibetan Plateau. However, there is a lack of understanding about the kiang population and its habitat in this region. This study aims to assess the population and habitat status of kiangs. The results showed that the area of suitable habitat for kiangs is 3402.45 km2, with an estimated population of 1395.00 ± 272.20, and a population density of 0.41 ± 0.08/km2. These findings provide a scientific reference for the conservation of the kiang population and its habitat in the region. Shiqu County, Sichuan Province, forms the eastern edge of the distribution area of the kiang (Equus kiang). It is important to assess the population and habitat status of peripheral populations, as these play a significant role in the development of conservation strategies for kiangs. Based on field transect data collected from July to August 2023, this study predicted the suitable habitat distribution of kiangs in Shiqu County using a MaxEnt model and estimated the population size and density using the 'Distance' package. Additionally, it analyzed the responses of the group size of kiangs to environmental factors in Shiqu County. The results showed that the area of suitable habitat for kiangs is 3402.45 km2, accounting for 13.51% of the total area of Shiqu County. The estimated population was 1395.00 ± 272.20, with a population density of 0.41 ± 0.08/km2. Additionally, the group size of kiangs was significantly positively correlated with the distance from the road and grazing site. The distance from the grazing site, elevation, and temperature annual range are the main environmental factors affecting the distribution of kiangs. This study initially revealed the peripheral population Status and suitable habitat of the kiang on the eastern Tibetan Plateau, and the potential threat of grazing interference and road obstruction. The research results can provide a scientific reference for the population and habitat protection of kiangs in this area. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales 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.)

One of the big challenges in machine learning is difficulty of achieving high accuracy in a short completion time. A more difficulties appeared when the algorithm needs to be used for solving real dataset from the survey-based data collection. Imbalance dataset, insufficient strength of correlations, and outliers are common problems in real dataset. To accelerate the modelling processes, automated machine learning based on meta-heuristics optimization such as genetic programming (GP) has started to emerge and is gaining popularity. However, identifying the best hyper-parameters of the meta-heuristics' algorithm is the critical issue. This paper demonstrates the evaluation of GP hyper-parameters in modeling machine learning on house affordability dataset. The important hyper-parameters of GP are population size (PS), that has been observed with different setting in this research. The machine learning with GP was used to predict house affordability among employers with transport expenditure and job mobility as some of the attributes. The results from testing that run on hold-out samples show that GP machine learning can reach to 70% accuracy with split ratio 0.2 and GP PS 30. This research contributes to the advancement of automated machine learning techniques, offering potential for faster and more accurate real survey-based datasets. [ABSTRACT FROM AUTHOR]

To optimize the operational availability of the series-parallel system and provide useful insights for maintenance planning, the study attempts to investigate the availability of a ball mill unit. These four different components make up the ball mill production system: "drum," "ring-gear," "gearbox," and "electric motor." There is a chain mechanism connecting all four components. The "ring gear" and "electric motor" components are composed of two independent units, one of which serves the desired purpose and the other is maintained in cold standby. The "drum" and "gearbox" of the components each contain only one unit. Therefore, a novel mathematical model is designed and implemented in this work by assuming arbitrary repair rates and exponentially distributed failure rates using the Markov process and Chapman-Kolmogorov equations. This study explored the availability with a normalization method and used genetic algorithm techniques to optimize ball mill availability. Putting this article into practice is of great benefit when developing an appropriate maintenance program. Through this, the study achieves maximum production. To investigate the behavior of several performance characteristics of the ball mill production system, numerical results and corresponding graphs are also specifically created for specific values of subsystem parameters, such as failure rate, and repair rate to increase the system's overall efficiency. [ABSTRACT FROM AUTHOR]

The issue of population disparity is a subject of interest for researchers, as the study of population distribution is related to the place and society, and their demographic movement according to administrative units. The research aimed to identify the nature of the demographic balance of the population variables in the study area and their population characteristics, including their distribution and the geographic factors affecting this distribution. However, this study relied on both theoretical and practical aspects, which addressed the development of the population and its relationship to natural and human factors. The result was that geographic factors have a clear impact on the distribution of the population of the district and the difference in their demographic balance, and the varying degree of influence of these factors in drawing the geographic distribution of the population. We note that the population of the district increased from (85,952 people) in 1997 to (172,116 people) in 2022, as these numbers varied according to the administrative unit and the environment. The urban environment recorded the highest population of (129,490 people), while in the rural environment, the population reached (42,626 people) in 2022. The district center represents the highest distribution in the urban environment, with a population of (101,493 people), while the lowest distribution of the population is in the Al-Khayr district, with a population of (9,682 people). This is due to the difference in the demographic balance of the population of the study area at the level of the two environments due to the availability of services and the high economic level, and the presence of administrative institutions in the urban environment, which made the district center a center for attracting the population and migration to it from other areas, while the rural environment suffers from low economic and service levels, dry climatic conditions, lack of job opportunities, and weak community services, which encouraged migration towards urban centers in general and the district center in particular. The population density recorded (105.9 people/km²) in 2022, after it was (35 people/km²) in 1997, due to the small area of the district compared to the size of its population. This density was not evenly distributed among its administrative units due to the variation in the distribution of geographic factors between the parts of the district, as the highest level was recorded in the district center, reaching (241.8 people/km²) due to the small area of (506 km²), which contributed to the high population density, and the lowest level was in the Al-Khayr district, with a rate of (36 people/km²) due to the large area of the district, which is (729 km²), in addition to being a repulsive environment for the population. [ABSTRACT FROM AUTHOR]

In capture–recapture experiments, the presence of overdispersion and heterogeneity necessitates the use of the negative binomial regression model for inferring population sizes. However, within this model, existing methods based on likelihood and ratio regression for estimating the dispersion parameter often face boundary and nonidentifiability issues. These problems can result in nonsensically large point estimates and unbounded upper limits of confidence intervals for the population size. We present a penalized empirical likelihood technique for solving these two problems by imposing a half-normal prior on the population size. Based on the proposed approach, a maximum penalized empirical likelihood estimator with asymptotic normality and a penalized empirical likelihood ratio statistic with asymptotic chi-square distribution are derived. To improve numerical performance, we present an effective expectation-maximization (EM) algorithm. In the M-step, optimization for the model parameters could be achieved by fitting a standard negative binomial regression model via the R basic function glm.nb(). This approach ensures the convergence and reliability of the numerical algorithm. Using simulations, we analyze several synthetic datasets to illustrate three advantages of our methods in finite-sample cases: complete mitigation of the boundary problem, more efficient maximum penalized empirical likelihood estimates, and more precise penalized empirical likelihood ratio interval estimates compared to the estimates obtained without penalty. These advantages are further demonstrated in a case study estimating the abundance of black bears (Ursus americanus) at the U.S. Army's Fort Drum Military Installation in northern New York. [ABSTRACT FROM AUTHOR]

Superabundant microbes (SAMs), such as marine phytoplankton, are extremely important in Earth's ecosystems. Evolutionary processes have been mainly studied in much smaller populations, and it is poorly understood how evolution works in the huge populations of SAMs. The standard tools of evolutionary genetics were developed for populations of smaller sizes, and many of these tools may not be suitable to study evolution in astronomically large SAM populations. Nucleotide sequence polymorphism is surprisingly low in SAMs, corresponding to a population of a few million individuals, but the reasons for this lack of diversity are unclear. Marine phytoplankton play crucial roles in the Earth's ecological, chemical, and geological processes. They are responsible for about half of global primary production and drive the ocean biological carbon pump. Understanding how plankton species may adapt to the Earth's rapidly changing environments is evidently an urgent priority. This problem requires evolutionary genetic approaches as evolution occurs at the level of allele frequency change within populations driven by genetic drift and natural selection (microevolution). Plankters such as the coccolithophore Gephyrocapsa huxleyi and the cyanobacterium Prochlorococcus 'marinus' are among Earth's most abundant organisms. In this opinion paper we discuss how evolution in astronomically large populations of superabundant microbes (SAMs) may act fundamentally differently than it does in the populations of more modest size found in well-studied organisms. This offers exciting opportunities to study evolution in the conditions that have yet to be explored and also leads to unique challenges. Exploring these opportunities and challenges is the goal of this article. [ABSTRACT FROM AUTHOR]

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The state of the invasive species Dreissena polymorpha (Pallas) was studied in Ivan'kovskoe (Ivan'kovo) Water Reservoir in 2018–2022 to obtain the quantitative parameters of the mollusk development at the larval and definitive stages in all pleses (moderately wide stretches of a water body that is deeper compared to the surrounding waters) of the water reservoir during different seasons, as well as to show the interannual dynamics of their population size and spatial distribution. In the Ivan'kovo Water Reservoir, the southern invasive species Dreissena polymorpha (Pallas) has adapted rather successfully and has occurred continuously in the subsaline water conditions with a persistent lack of dissolved oxygen in summer in the near-bottom waters, which caused a shift in the mollusk niche down to a depth of 4 m; the mussel did not occur in silty biotopes. Range expansion of the southern immigrant D. polymorpha to the northern regional water bodies is influenced by climate warming, which prolongs the reproductive process of this mollusk. Currently, the end dates of mussel spawning in the Upper Volga water reservoirs approach those in southern water bodies. Eutrophication enhancement due to climate changes may pose a serious threat to Ivan'kovo Water Reservoir. Overall, the mussel population (adult mollusks + veligers) play a significant role in the process of self-purification of the water reservoir. [ABSTRACT FROM AUTHOR]

Missing covariates are not uncommon in capture–recapture studies. When covariate information is missing at random in capture–recapture data, an empirical full likelihood method has been demonstrated to outperform conditional-likelihood-based methods in abundance estimation. However, the fully observed covariates must be discrete, and the method is not directly applicable to continuous-time capture–recapture data. Based on the Binomial and Poisson regression models, we propose a two-step semiparametric empirical likelihood approach for abundance estimation in the presence of missing covariates, regardless of whether the fully observed covariates are discrete or continuous. We show that the maximum semiparametric empirical likelihood estimators for the underlying parameters and the abundance are asymptotically normal, and more efficient than the counterpart for a completely known non-missingness probability. After scaling, the empirical likelihood ratio test statistic for abundance follows a limiting chi-square distribution with one degree of freedom. The proposed approach is further extended to one-inflated count regression models, and a score-like test is constructed to assess whether one-inflation exists among the number of captures. Our simulation shows that, compared with the previous method, the proposed method not only performs better in correcting bias, but also has a more accurate coverage in the presence of fully observed continuous covariates, although there may be a slight efficiency loss when the fully observed covariates are only discrete. The performance of the new method is illustrated by analyses of the yellow-bellied prinia data and the rana pretiosa data. [ABSTRACT FROM AUTHOR]

Differential Evolution (DE) stands as a potent global optimization algorithm, renowned for its application in addressing a myriad of practical engineering issues. The efficacy of DE is profoundly influenced by its control parameters and mutation strategies. In light of this, we introduce a refined DE algorithm characterized by adaptive parameters and dual mutation strategies (APDSDE). APDSDE inaugurates an adaptive switching mechanism that alternates between two innovative mutation strategies: DE/current-to-pBest-w/1 and DE/current-to-Amean-w/1. Furthermore, a novel parameter adaptation technique rooted in cosine similarity is established, with the derivation of explicit calculation formulas for both the scaling factor weight and crossover rate weight. In pursuit of optimizing convergence speed whilst preserving population diversity, a sophisticated nonlinear population size reduction method is proposed. The robustness of each algorithm is rigorously evaluated against the CEC2017 benchmark functions, with empirical evidence underscoring the superior performance of APDSDE in comparison to a host of advanced DE variants. [ABSTRACT FROM AUTHOR]

Despite the high diversity of elasmobranch fishes in the Balearic Islands, knowledge of their biology and population dynamics is still scarce. A recent mark-and-recapture experiment off the Balearic Islands tagged 3738 individuals of 23 shark and batoid species during MEDITS and CANAL bottom trawl scientific surveys from June 2021 to August 2023. Retrieval was reported for the sharks Scyliorhinus canicula and Mustelus mustelus, revealing relatively small home ranges for these species (0.2–38.5 km and 7.8–15.3 km for S. canicula and M. mustelus, respectively). Recapture efficiency was higher from scientific surveys than from commercial catches, highlighting potential challenges in collaboration with fishermen and recapture reports. Density estimates obtained from the MEDITS bottom trawl survey suggest a much larger population for S. canicula than estimates from the mark–recapture data, indicating MEDITS density estimates for this species may be overestimated due to its scavenger behavior perhaps favoring individuals searching for discards aggregated in the fishing grounds. This study emphasizes the importance of monitoring, collaborative efforts, and improved reporting mechanisms to enhance our understanding of elasmobranch populations and provide support for sustainable management of these vulnerable marine species. [ABSTRACT FROM AUTHOR]

Reef manta rays (Mobula alfredi) face threats from human exploitation and activity in several regions of the world and crucial information on the ecology of the species is needed. The species is observed at several sites in all parts of the archipelago of New Caledonia where anthropogenic influence is presumed to be minimal. This study is the first to investigate the population of New Caledonia and focuses on its characteristics and its habitat use. Photographs of reef manta rays were collected directly from the authors (14.4%) between 2017 and 2020 and gathered from recreational divers and snorkelers (85.6%) from 11 sites around New Caledonia. The authors used the unique ventral coloration patterns of the manta rays that were clearly identifiable from 1741 of these photographs to identify 391 individuals and record their physical characteristics (sex, injuries, and colour morph) and resighting rates. These results highlight the widespread distribution of the species in the archipelago (11 sites) with little connectivity between all aggregations sites, with only 5.4% of the individuals observed at more than one site. Strong and long-term site fidelity was recorded at all studied sites through re-sighting rates (52.2% overall) and residency analysis. The population also records the world highest known proportion of melanistic manta rays (43%) to date, and a balanced male: female ratio (1.0:1.15). The analysis of injuries reported that 44.8% of all reef manta rays identified (n = 391) had noticeable wounds or injuries with no significant difference in the proportions of males and females injured. From these injured individuals only 9.8% of injuries judged to be of anthropogenic origin and 29.7% from attempted predation. Our study complements and correlates previous findings on this population that revealed strong site fidelity and low connectivity. The different characteristics of this population of reef manta rays also emphasize that concerns about species in New Caledonia are limited and that such favourable context needs to be preserved as reference for conservation. [ABSTRACT FROM AUTHOR]

The forest musk deer (Moschus berezovskii) is a national Class I protected wild animal in China, and the IUCN Red list classifies it as globally endangered. It has significant value in traditional Chinese medicine and spices. However, wild M. berezovskii has faced a severe population decline due to human hunting, habitat loss, and fragmentation. Thus, studying its population size and distribution pattern is of great importance to develop effective conservation measures. Here, we determined the optimal MaxEnt model and used stratified sampling and the fecal pile counting method to predict the population size and potential habitat distribution of wild M. berezovskii in Chongqing using 133 species distribution points and 28 environmental variables. The results were as follows: (1) When the optimal model parameters were RM = 3.5 and FC = LQHPT, it had high model prediction accuracy (AUC = 0.909 ± 0.010, TSS = 0.663). (2) Under various climatic, topographic, vegetation, and anthropogenic disturbance scenarios, M. berezovskii was primarily distributed in northern, eastern, southwestern regions of Chongqing, covering an area of approximately 5562.80 km2. (3) The key environmental factors affecting the potential habitat distribution of M. berezovskii were elevation (36.5%), normalized difference vegetation index (NDVI, 16.6%), slope (11.8%), and land-use type (7.6%), whereas climate and anthropogenic disturbance factors had relatively little influence. (4) A population estimation for M. berezovskii identified approximately 928 ± 109 individuals in Chongqing. We recommend prioritizing the preservation of high-altitude habitats and native vegetation to mitigate human interference and minimize road damage. In summary, our results can enhance the understanding of M. berezovskii distribution and provide a basis for effective conservation and management initiatives. [ABSTRACT FROM AUTHOR]

AbstractNumerous studies have attempted to identify potential risk-factors associated with COVID-19 infection, including inter alia: age, diet, higher population density, and the quality and availability of health services. The objective of the current study is to analyze the weight of four covariates on a daily infection rate from SARS-COV2 virus. The method used is regression analysis, where each variable is converted to the standard normal distribution function. Results demonstrate that of the four investigated covariates, vaccination and population size have the highest weights. Given the empirical analysis, the most efficient way to achieve a reduction in the spread of the pandemic is via appropriate vaccination programs.

The suburban zone of Wroclaw is characterised by dynamic population changes and increased construction traffic. However, the pace of the changes taking place is not fully reflected in official population statistics, based on registration data, presenting a much lower population than actually resides in the suburban municipalities. The purpose of the article is to estimate the actual population of the Wroclaw suburban zone for data from 2012/13 and 2020, and to show the degree of the differentiation of the population transition taking place in individual reference units. The estimation of the population size was made on the basis of the author’s method, based on the aggregation and comparison of statistical data on registrations from the register of the General Electronic System of Population Registration (PESEL) and vector spatial data from the Database of Topographic Objects (BDOT10k). From 2012/13 to 2020, the population of suburban zone of Wrocław almost doubled compared to official statistics data. The highest level of the underestimation of the actual population was observed in villages located near main communication routes and in the closet vicinity to Wrocław city. Those are places where the suburbanistion processes were observed the earliest.

Introduction: Quantitative assessment of fish abundance is the basis of scientific research andmanagement of their population. Demographic studies of stream-dwelling salmonids haveshown that variation in their abundance on a spatio-temporal scale is common, and troutpopulations are no exception. Understanding this variation is crucial for several reasons,including designing and interpreting environmental impact assessment studies and monitoringfishery management strategies. The present study aimed to estimate the spatial and temporalvariations in the density of Caspian Sea trout in some of the Lar National Park streams andinvestigate the relationship between the density of fish in these streams and the density ofbenthic invertebrates as their primary food sources.Material and Methods: Fish densities were calculated using the Le Cren depletion method toachieve reliable population estimates. After two removal steps, the total number of fish caughtwas standardized and expressed as density per 100 m2 of the river channel. To investigate thetemporal changes of fish abundance, the study results in 2009 were qualitatively compared withthe results of another study in 2017.Results and Discussion: According to the 2009 results, the highest Caspian Sea trout densitywas recorded in the Delichay (44 per 100 m2), Lar (43.2 per 100 m2), and Siah Palas sites (33.4per 100 m2), respectively, and the lowest densities were recorded in the Lar (Kharsang, 10.5per 100 m2) and Lar (Sorkhak, 11.5 per 100 m2). In 2017, the highest density of trout wasdocumented in Siah Palas (175 per 100 m2), Delichay (Vararo, 118 per 100 m2), and Elam (112per 100 m2) streams, and the lowest density was recorded in the Delichay (downstream, 48 per100 m2) and Absefid (49 per 100 m2) streams.The distribution and abundance of stream-dwelling salmons are primarily regulated by food andspace. The abundance of Caspian Sea trout on a local scale indicates variety in quality and habitataccess for Caspian Sea trout in the Lar National Park. We speculated that habitat diversity hasinfluenced the density of Caspian Sea trout in various streams in the region by affecting theabundance of aquatic invertebrates, which are the main prey source. However, the results ofregression (R2= 0.02, p value = 0.72) and correlation (Spearman, r = 0.24) analyses showed nosignificant relationship between the density of fish and benthic invertebrates in the Lar National Parkstreams. Despite the enough abundance of prey in Lar streams, the fish were low in density. Thecause of this incongruence is probably related to the salmon fishing in Lar National Park in the past.Comparing fish densities in 2009 and 2017 showed that the trout density in 2017 was higherthan the trout density in 2009.Conclusion: Considering that in 2014, the Department of Environment stopped issuing fishinglicenses in this area, one of the reasons for the increase in fish density is probably a positiveeffect of the fishing prohibition on this species. Since Caspian Sea trout abundances in the LarNational Park streams are spatio-temporally variable, it is necessary to provide reasonablemanagement strategies and continuous monitoring to prevent them from global warming andconserve them in the streams of the Lar National Park. Furthermore, due to climate change andbeing at risk of other populations of Caspian Sea trout in different habitats in Iran, thispopulation should be protected as a support population.

Background. Today, the black-headed gull inhabits man-made areas of wastewater treatment facilities (WTF) to comensate for the the reduction of natural aquatic and wetland habitats. Over the last decade, a nearly tenfold increase in its population has been recorded, despite a low reproduction rate. This fact indicates the lack of stability in the bird population, necessitating thorough research. Materials and Methods. The analysis of the population size and biological charac­teristics of black-headed gulls involved censuses and observations at the WTF of the city of Kharkiv using conventional methods during the spring-summer periods of 2020–2021 and 2023. Results. The population of the black-headed gull reached its peak in the third decade of May 2020 (2637 individuals) and 2023 (2124 individuals), as well as in the second decade of May 2021 (3949 individuals). The maximum nesting density was observed on sludge sites (SS) of wastewater treatment facilities that are most similar to natural habitats, where dried mud alternates with water patches and vegetation at the bottom and around the perimeter (Type V): 236.7±26.7 pairs/ha in 2020 and 242.9±28.5 pairs/ha in 2021. The majority of nests were found in the first decade of May 2021 and the third decade of May 2020. The black-headed gull forms mixed-species, occasionally monospecific subcolonies. Nesting in association with it were: Sterna hirundo, Anas platyrhynchos, Spatula clypeata, Vanellus vanellus, Charadrius dubius, Himantopus himantopus, Fulica atra, Gallinula chloropus, and Aythya ferina. The size of the complete black-headed gull clutch was 3.1±0.4 eggs (n = 190). The egg dimensions were 50.9±2.1 ´ 36.2±1.1, with a mass of 34.6±2.8 g. Regarding shell coloration, five types of background colors were identified. Mass egg laying occurred from the third decade of April to the first decade of May, constituting 40.3 % (n = 993) in 2020 and 62.3 % (n = 1757) in 2021. The egg-laying period extended from April to July, with the latest non-incubated clutches recorded in the first decade of July (3.07.2020). The first chicks were found in nests in the first decade of May, while mass hatching occurred in the second half of May. The latest registration dates of the birds on nesting territories were in the second decade of July for 2020 and 2023, and the first decade of August for 2022. The nesting season duration varied from 125 to 140 days in different years. Autumn migration commenced with summer relocations and concluded from late October to early November. The reproductive success – the percentage of nestlings that fledged and successfully achieved flight – constituted 29.2 % (n = 2404 of laid eggs) in 2020, and 15.5 % (n = 6138) in 2021. The majority of offspring perished due to changes in water levels (prolonged rainfall or industrial wastewater discharge), predation, disturbance factors, etc. Conclusion. The colonial nesting of the black-headed gull creates favorable conditions for the habitation and reproduction of various bird species, including rare ones, which is essential for their conservation.

This study investigates how language‐internal constraints regulate the future temporal reference (FTR) alternation across nine varieties of English around the world. We specifically marshal Variation‐Based Distance & Similarity Modeling (VADIS) to calculate distances between the varieties under study as a function of the non‐correspondence of the ways in which language users choose between FTR variants. Our linguistic data come from the spoken component of the International Corpus of English: the dataset covers 500 future marker observations per variety of English (Ntotal = 4500), richly annotated for seven language‐internal constraints (such as polarity and sentence type). VADIS uncovers a number of probabilistic grammar differences between the varieties of English under study, which are subsequently correlated with four language‐external distance measures: geographical distance, travel time distance, population size and GDP per capita. Mantel correlation analysis shows that language‐internal distances do not correlate with language‐external distances. [ABSTRACT FROM AUTHOR]

Lately, 2 species of lepidopteran insects, Ostrinia nubilalis and Helicoverpa armigera, are very common in corn crops in the west of the country. They have the status of a pest in the larval stage and are a big problem for the phases after the formation of the cob when the attack itself is manifested. Recent studies as well as the opinions of farmers speak of an increase in the size of the adult populations and implicitly of the reproductive capacity and the number of harmful larvae in the crops. The present work comes with recognition information and comparison between the 2 species, both at the adult and larval levels, but also at other important stages in identification (pupa and egg). Among others already known, the identification of adults is easier because those of Helicoverpa are larger, with a more pronounced coloration than those of Ostrinia which are thinner in body, small in wingspan and lighter in color, more uniform. Our studies of corn crops in Palota locality (Bihor County) showed that the larvae are also differentiated by size and coloration in the same trend as the adult. The damage phenophases are somewhat staggered but concentrated especially during the cob formation period. While Ostrinia is specific to corn, Helicoverpa can attack various plants. The analysis of the size of the populations from the last 2 years highlighted a preponderance of the Helicoverpa species at the expense of Ostrinia. These differences are useful in identifying the species more quickly and taking appropriate measures for effective control. [ABSTRACT FROM AUTHOR]

This study focuses on the wild Asian elephant (Elephas maximus) that appeared in the Wild Elephant Valley, Mengyang, Xishuangbanna. The imaging data collected from 2002 to 2023 were used to carry out individual identification of Asian elephants based on morphological features, and a total of 152 individuals were identified. The quantitative characteristics of the population were also analyzed. The number of Asian elephant population in this area increased from 36 in 2002 to 112 in 2023, and the main increase was from birth rather than migration, with an average annual birth rate of 8. 29% and an average annual population growth rate of 5. 78%. The majority of individuals in this population are minors, making it a growing population. For the population in 2023, the proportion of males was slightly higher than females at the young age, but as the age increased, the male ratio decreased and eventually adult females outnumbered adult males. Analysis of some reproductive parameters for wild female Asian elephants revealed that this wild population was in good reproductive condition. The results of this study show that Asian elephants in Mengyang area of Xishuangbanna, Yunnan, China have been effectively protected against global Asian elephant population decline. [ABSTRACT FROM AUTHOR]

In order to understand the population abundance and dynamic of crab-eating frog (Fejervarya cancrivora)in the mangrove of Hainan Dongzhaigang National Nature Reserve, 34 line transects were investigated in tidal ditches of mangrove from 2020 to 2022. Further, the risk factors affecting the frog population in the reserve were analyzed, and some suggestions on protection and management were informed. The results showed that crab-eating frogs mainly distributed in the regions of Management Bureau, Daoxue and Sanjiang, but absent in Tashi and Bodu. The population density of crab-eating frog was highest in Sanjiang, then in Daoxue and lowest in Management Bureau. The population density of Sanjiang, Daoxue, Management Bureau were 221. 6 individuals/hm², 164. 7 individuals/hm², 137. 4 individuals/hm² respectively in 2020, which was significantly higher than that in 2022 (151. 2 individuals/hm² in Sanjiang, 144. 8 individuals/hm² in Daoxue and 116. 3 individuals/hm² in Management Bureau) and 2021 (113. 2 individuals/hm² in Sanjiang, 99. 6 individuals/ hm² in Daoxue and 51. 9 individuals/hm² in Management Bureau). The total population of Sanjiang, Daoxue and Management Bureau were 6, 498, 3, 357, 4, 847 respectively from 2020 to 2022. Higher salinity, water pollution, epiphytic oyster and small tidal bare beach area were the main factors leading to the absence of crab-eating frog in Tashi and Bodu. The illegal capture, reduction of breeding habitats and pollution caused by aquaculture ponds are threatening factors to the populations of crab-eating frog. [ABSTRACT FROM AUTHOR]

Juvenile survival is critical to population persistence and evolutionary change. However, the survival of juvenile plants from emergence to reproductive maturity is rarely quantified. This is especially true for long‐lived perennials with extended pre‐reproductive periods. Furthermore, studies rarely have the replication necessary to account for variation among populations and cohorts. We estimated juvenile survival and its relationship to population size, density of conspecifics, distance to the maternal plant, age, year, and cohort for Echinacea angustifolia, a long‐lived herbaceous perennial. In 14 remnant prairie populations over seven sampling years, 2007–2013, we identified 886 seedlings. We then monitored these individuals annually until 2021 (8–15 years). Overall, juvenile mortality was very high; for almost all cohorts fewer than 10% of seedlings survived to age 8 or to year 2021. Only two of the seedlings reached reproductive maturity within the study period. Juvenile survival increased with distance from the maternal plant and varied more among the study years than it did by age or cohort. Juvenile survival did not vary with population size or local density of conspecific neighbors. Our results suggest that low juvenile survival could contribute to projected population declines. [ABSTRACT FROM AUTHOR]

We examine whether electoral preferences depend on a community's population size by studying post-Second World War Baden-Württemberg in Southwest Germany. Our identification strategy exploits the fact that the French administration zone prohibited German expellees from entering, contrary to the contiguous American zone. Population size positively predicts voting for the Social Democrats (the party advocating substantial government involvement in practically all domains) and negatively for the Christian Democrats (the small-government party advocating free-market policies). Results are neither driven by pre-existing voting patterns, religious compositions, and location- and time-specific unobservables, nor other measurable cultural, demographic, economic, or political characteristics. Alternative explanations pertaining to expellee voting behaviour or a backlash of natives against expellees appear unlikely – population size prevails as a predominant voting predictor. [ABSTRACT FROM AUTHOR]

This paper summarizes a two-year (2021 and 2022) survey which sought to determine the breeding population of White-backed Woodpecker (Dendrocopos leucotos) in Hungary. The survey was initiated by the Hungarian Woodpecker Group of MME/BirdLife Hungary and was the first to be conducted nationwide on this species. All hill ranges where the species was historically known to occur were visited. A total of 31 observers were involved, and 102 UTM squares in which White-backed Woodpeckers were known to breed, or potentially breed, were visited. The results suggest that the Hungarian breeding population of this endangered species ranges between 480 and 800 pairs. [ABSTRACT FROM AUTHOR]

Introduction: Quantitative assessment of fish abundance is the basis of scientific research and management of their population. Demographic studies of stream-dwelling salmonids have shown that variation in their abundance on a spatio-temporal scale is common, and trout populations are no exception. Understanding this variation is crucial for several reasons, including designing and interpreting environmental impact assessment studies and monitoring fishery management strategies. The present study aimed to estimate the spatial and temporal variations in the density of Caspian Sea trout in some of the Lar National Park streams and investigate the relationship between the density of fish in these streams and the density of benthic invertebrates as their primary food sources. Material and Methods: Fish densities were calculated using the Le Cren depletion method to achieve reliable population estimates. After two removal steps, the total number of fish caught was standardized and expressed as density per 100 m² of the river channel. To investigate the temporal changes of fish abundance, the study results in 2009 were qualitatively compared with the results of another study in 2017. Results and Discussion: According to the 2009 results, the highest Caspian Sea trout density was recorded in the Delichay (44 per 100 m² ), Lar (43.2 per 100 m² ), and Siah Palas sites (33.4 per 100 m² ), respectively, and the lowest densities were recorded in the Lar (Kharsang, 10.5 per 100 m² ) and Lar (Sorkhak, 11.5 per 100 m² ). In 2017, the highest density of trout was documented in Siah Palas (175 per 100 m² ), Delichay (Vararo, 118 per 100 m² ), and Elam (112 per 100 m² ) streams, and the lowest density was recorded in the Delichay (downstream, 48 per 100 m² ) and Absefid (49 per 100 m² ) streams. The distribution and abundance of stream-dwelling salmons are primarily regulated by food and space. The abundance of Caspian Sea trout on a local scale indicates variety in quality and habitat access for Caspian Sea trout in the Lar National Park. We speculated that habitat diversity has influenced the density of Caspian Sea trout in various streams in the region by affecting the abundance of aquatic invertebrates, which are the main prey source. However, the results of regression (R²= 0.02, p value = 0.72) and correlation (Spearman, r = 0.24) analyses showed no significant relationship between the density of fish and benthic invertebrates in the Lar National Park streams. Despite the enough abundance of prey in Lar streams, the fish were low in density. The cause of this incongruence is probably related to the salmon fishing in Lar National Park in the past. Comparing fish densities in 2009 and 2017 showed that the trout density in 2017 was higher than the trout density in 2009. Conclusion: Considering that in 2014, the Department of Environment stopped issuing fishing licenses in this area, one of the reasons for the increase in fish density is probably a positive effect of the fishing prohibition on this species. Since Caspian Sea trout abundances in the Lar National Park streams are spatio-temporally variable, it is necessary to provide reasonable management strategies and continuous monitoring to prevent them from global warming and conserve them in the streams of the Lar National Park. Furthermore, due to climate change and being at risk of other populations of Caspian Sea trout in different habitats in Iran, this population should be protected as a support population. [ABSTRACT FROM AUTHOR]

The Santa Cruz black salamander Aneides niger is a priority 3 California species of special concern with a restricted geographic range confined to the Santa Cruz Mountains. Anecdotal observations suggest that the species was relatively abundant in the early 1900s, but it has become more difficult to find in the past few decades. To better understand if the species has undergone population size fluctuations, we analyzed mitochondrial and nuclear sequence data to examine levels of genetic variation and phylogeographic structure, and test for signatures of population size change. We then reconstructed the climatic suitability for the species to 1) determine if past climate fluctuations could have influenced range size and genetic diversity, and 2) estimate the effects of future climate change on geographic range suitability as a proxy for possible future population size change. Genetic analyses detected low levels of genetic variation and a general lack of genetic structuring, suggesting a recent genetic bottleneck. While neutrality tests of individual loci were nonsignificant, skyline plot and isolation-with-migration analyses detected a relatively recent reduction in population size. Interpretation of these genetic results should consider the limited number of localities and individuals sampled for this species. Climatic suitability for Santa Cruz black salamanders was much lower during the last glacial maximum, which could be the cause of the detected historical change in population size. Future projections of climatic suitability under a high-emission scenario suggest a dramatic geographic range restriction to coastal areas. These projections highlight the need for the protection of coastal habitat patches to preserve existing coastal populations, and to maintain connectivity between coastal and inland habitats to allow the westward movement of populations and genes in response to climate change. [ABSTRACT FROM AUTHOR]

There has been a limited number of studies on the effects of harmful algal blooms (HABs) on natural rocky intertidal ecosystems. From mid-September to early November 2021, an unprecedented HAB caused by Karenia selliformis hit the Pacific coast of southeast Hokkaido, Japan, for the first time, causing massive mortalities among marine organisms. To clarify the immediate impacts of the HAB on the abundance of 10 rocky intertidal species in four functional groups (macroalgae, sessile invertebrates, molluscan grazers, and molluscan carnivores), we focused on two questions: (1) How did the HAB affect the abundance of each species differently at the regional scale? and (2) How did the impacts of the HAB on the abundance of each functional groups vary spatially, and was the spatial variation of the HAB impacts related to the spatial distribution of the cell density of HAB species? To study these issues, we compared census data for 17 years before the HAB and within one month after it for five shores on the southeast coast of Hokkaido. The results showed that two macroalgae species and all three molluscan grazer species declined significantly after the HAB. Moreover, the decrease in molluscan grazers was significantly correlated with cell density. These results suggest that the impacts of the HAB in southeast Hokkaido on the abundance of rocky intertidal organisms are highly variable depending on species and locality, presumably because of differences in species-specific tolerances to HAB toxins and the spatial variation in the density of the HAB organisms. [ABSTRACT FROM AUTHOR]