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This article presents the results of the study of ecological and biological characteristics of common carp (Cyprinus carpio Linnaeus, 1758) from Kapchagay Reservoir on the Ili River in Kazakhstan. We studied size-weight indices, body condition (Fulton condition factor), age structure, fecundity, and body length. We also determined the gonadosomatic index (GSI) during the spawning period. Fish samples were caught using fixed nets with mesh diameters ranging from 16 to 90 mm. Total body length (TL) in mm and total body weight (TW) of fish in grams were measured. A logistic regression model was used to determine body size at first maturity for females and males. Fecundity was determined in mature females (stage IV maturity). Calculation of the GSI made it possible to clarify the duration of the spawning period. This study provides important information about the troubling status of the population of C. carpio in the area of study and suggests effective approaches to regulate fisheries in the reservoir and other water bodies of Kazakhstan. There is clearly a need to limit IUU (illegal, unreported and unregulated) fishing and otherwise regulate over-fishing. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Raptor Research is the property of Raptor Research Foundation 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.)

Individual recognition during fieldwork is necessary when estimating the size of a population for conservation or management purposes. We used a non-invasive method of individual photo identification based on dorsal color patterns. Our study aimed to estimate the size of two green toad Bufotes viridis populations in an urban habitat to provide input for conservation activities. The study was conducted in the two largest known breeding sites of the species in Poznań, Western Poland: Cytadela Park (PC) and Rataje Park (PR). We collected animals within each site's breeding habitat twice during the mating season. Dorsal pattern photographs and morphometric measurements were taken, after which the animals were released immediately. We analyzed the pictures by single-eye matching to estimate the population size using the Chapman estimator. Most individuals caught were males, and no females were recaptured. Therefore, we used only data for males and then estimated the total population size based on a calculation using the sex ratio known from the literature. The number of captured toads was higher at the PC site than at the PR site. Toads from the PC population were noticeably larger and had higher condition value indices than those from the PR population. This result is consistent with the management and history of both sites. We observed habitat transition and potential mortality due to park construction the year before our study at the PR site. In contrast, the PC site is a mature green area with more than 50 years of stable management. Despite some limitations, photo-identification may be an essential first step in estimating population size in community-based conservation initiatives for the green toad, enabling conservationists to enter the public discussion about urban conservation, providing a reference for the conservation value of urban breeding sites, and as a consequently, providing input for active conservation and habitat management (e.g., fish removal and mowing regime modifications). [ABSTRACT FROM AUTHOR]

Objective: The Atlantic blue crab Callinectes sapidus (hereafter, "blue crab") is an ecologically and economically important species that supports one of the highest valued commercial fisheries in coastal South Carolina, USA. Researchers at the South Carolina Department of Natural Resources conduct multiple surveys to monitor the status of the blue crab by using a variety of gear configurations. Demographic characterizations can often be influenced by sampling gear‐related biases. Methods: We compared blue crab sex ratios between passive, pot‐based sampling and active, trawl‐based sampling in the fall across three estuaries and for year‐round sampling in a single estuary (Ashley River, South Carolina). Result: During the fall, there was a difference of 20.1% between the percentage of males collected in pot‐based sampling (73.5%) and the percentage of males in trawl‐based sampling (53.4%). Furthermore, an overall male bias of 23.0% was observed for year‐round sampling in the Ashley River; however, this bias was only significant in certain months. Conclusion: Our findings suggest that although particular sampling gears may have specific advantages, such as greater suitability to effectively sample certain habitats, the resulting characterizations of blue crab population demographics can differ among gear types. Recognizing gear‐related biases is important for ensuring that field surveys are representative of population demographics, particularly when sex‐specific modeling approaches are used as part of stock assessments to determine population status. Impact statementIn this study, we found that fisheries‐independent, pot‐based sampling produced blue crab catches that in many cases were significantly biased toward males when compared to catches from trawl‐based sampling. This finding has implications for sex‐specific stock assessments of blue crabs using fisheries‐independent data. [ABSTRACT FROM AUTHOR]

Background: Prolonged disability resulting from road traffic injuries (RTIs) contributes significantly to morbidity and disease burden. A good understanding of the prevalence and the level of disability of orthopaedic injuries in developing countries is crucial for improvement; however, such data are currently lacking in Rwanda. Objectives: To determine the prevalence and levels of disability of 2 years post-road traffic orthopaedic injuries in Rwanda. Method: A multicentre, cross-sectional study from five Rwandan referral hospitals of 368 adult RTI victims' sustained from accidents in 2019. Between 02 June 2022, and 31 August 2022, two years after the injury, participants completed the World Health Organization Disability Assessment Schedule (WHODAS 2.0) Questionnaire for the degree of impairment and the Upper Extremity Functional Scale and Lower-Extremity Functional Scale forms for limb functional evaluation. Descriptive, inferential statistics Chi-square and multinomial regression models were analysed using R Studio. Results: The study's mean age of the RTOI victims was 37.5 (±11.26) years, with a sex ratio M: F:3: 1. The prevalence of disability following road traffic orthopedic injury (RTOI) after 2 years was 36.14%, with victims having WHODAS score > 25.0% and 36.31% were still unable to return to their usual activities. Age group, Severe Kampala Trauma Score and lack of rehabilitation contributed to disability. The most affected WHODAS domains were participation in society (33%) and life activities (28%). Conclusion: The prevalence and levels of disability because of RTOI in Rwanda are high, with mobility and participation in life being more affected than other WHODAS domains. Middle-aged and socio-economically underprivileged persons are the most affected. Contribution: This study showed that a good rehabilitation approach and economic support for the RTI victims would decrease their disabilities in Rwanda. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Accurate sex determination of an individual is essential for understanding the ecology of a species and to implement effective conservation measures. Molecular sexing is proving to be an effective tool to determine the sex ratio of difficult-to-sex species as well as for establishing breeding pairs in ex situ conservation programmes. In the last few decades, a putatively universal set of primers, based on the so-called intron A of the CHD1 gene, has been used to sex birds through PCR. Nevertheless, several issues have been reported in several taxa for which more specific alternative protocols are needed. In this paper we present a new pair of markers based on the so-called intron E of the CHD1 gene and designed for sexing difficult-to-sex Old World bunting Emberiza spp. individuals. This method was then used for supporting an ongoing Eastern Iberian Reed Bunting Emberiza schoeniclus witherbyi breeding programme and to estimate, for the first time, the sex ratio of this critically endangered passerine. Newly designed primers allowed for more rapid and accurate sex determination compared to other previously developed markers tested here, thanks to larger size differences between CHD1W and CHD1Z PCR products and lower allelic drop-out frequency. Our results suggest no significant sex bias in the Eastern Iberian Reed Bunting resident population (male:female ratio 0.8:1), as opposed to strongly female-biased estimates (up to male:female ratio 0.33:1) previously recorded in Spain for wintering populations. Differences in sex ratio estimates between resident and wintering populations could arise from a latitudinal sex segregation in Reed Buntings due to differential migration, and highlight the importance of using resident populations to obtain key demographic parameters. Future work should focus on sampling resident populations to better characterise local variations in sex ratio, to obtain relevant data for the management of threatened subspecies.—Alambiaga, I., Monrós, J.S. & Palero, F. (2024). New primers for sexing juvenile buntings and to assist ex-situ conservation of endangered Eastern Iberian Reed Bunting Emberiza schoeniclus witherbyi populations. Ardeola, 71: 119-130. La determinación precisa del sexo de un individuo es esencial para comprender la ecología de una especie y poder aplicar medidas de conservación eficaces. El sexado mediante técnicas moleculares proporciona una herramienta esencial en especies difíciles de sexar para determinar la proporción de sexos de poblaciones salvajes, así como para establecer parejas reproductoras en programas de conservación ex situ. En las últimas décadas, para el sexado de aves mediante PCR se ha utilizado ampliamente un par de cebadores, supuestamente universales, basados en el denominado intrón A del gen CHD1. No obstante, se han constatado problemas en su aplicación en diferentes taxones para los que se precisan protocolos alternativos más específicos. En este trabajo presentamos un nuevo par de cebadores basados en el intrón E del gen CHD1 diseñados para sexar muestras de escribanos Emberiza spp. de difícil sexado molecular. Este método ha sido utilizado para dar soporte a un programa de cría en cautividad del escribano palustre iberoriental Emberiza schoeniclus witherbyi y para estimar, por primera vez, la proporción de sexos en este paseriforme palustre en peligro de extinción. Los nuevos cebadores permitieron un sexado más eficaz que otros marcadores desarrollados previamente debido a las mayores diferencias de tamaño entre los productos de PCR de los alelos CHD1W y CHD1Z, y a la menor frecuencia en la presencia de alelos nulos. Nuestros resultados indican que no hay un sesgo sexual significativo en la población del residente escribano palustre iberoriental (proporción macho:hembra de 0,8:1), en contraste a las estimaciones fuertemente sesgadas hacia las hembras (hasta proporción macho:hembra de 0,33:1) previamente registradas en España para las poblaciones invernantes. Las diferencias en la proporción de sexos entre las poblaciones residentes e invernantes podrían deberse a una segregación latitudinal por sexos de la especie debido a la migración diferencial, y ponen de manifiesto la importancia de utilizar poblaciones residentes para conocer parámetros demográficos esenciales. Futuros trabajos deberían centrarse en el muestreo de poblaciones residentes para caracterizar mejor las variaciones locales en la proporción de sexos y obtener así información relevante para la gestión de subespecies amenazadas.—Alambiaga, I., Monrós, J.S. y Palero, F. (2024). Nuevos cebadores para sexar juveniles de escribano y asistir a la conservación ex-situ de poblaciones amenazadas del escribano palustre iberoriental Emberiza schoeniclus witherbyi. Ardeola, 71: 119-130. [ABSTRACT FROM AUTHOR]

Urbanization increasingly causes alterations in prey diversity and abundance, land cover, and human disturbance, subsequently impacting populations of even the most adaptable species. American Kestrels are currently considered urban adapters, which may be veiling the influence of urbanization on their continental population decline. We quantified overwintering abundance and sex ratios of American Kestrels throughout the past three decades in a rapidly developing region of the species' wintering range in southeast Florida to study spatial and temporal population trends relative to degree of urbanization. We detected a significant negative correlation between annual building density and kestrel abundance. Sex ratios also significantly shifted from predominantly female to predominantly male over time and in association with increased residential development. This trend suggests that developed landscapes may represent lower quality territories, as females typically occupy better quality overwintering habitat than males. These results suggest that urbanization may negatively impact overwintering American Kestrel populations in this region and should be investigated as a possible factor contributing to the overall continental population decline, particularly in the eastern flyway where urbanization is prevalent. La urbanización causa cada vez más alteraciones en la diversidad y abundancia de presas, la cobertura del suelo y la perturbación humana, impactando posteriormente en las poblaciones incluso de las especies más adaptables. Falco sparverius es considerada actualmente como una especie adaptada a los ambientes urbanos, lo que podría estar enmascarando la influencia de la urbanización en su declive poblacional continental. Para estudiar las tendencias poblacionales espaciales y temporales en relación con el grado de urbanización, cuantificamos la abundancia invernal y las proporciones de sexos de F. sparverius a lo largo de las últimas tres décadas en una región de rápido desarrollo urbano dentro del área de invernada de la especie en el sureste de Florida. Detectamos una correlación negativa significativa entre la densidad anual de edificios y la abundancia de individuos de F. sparverius. Con el tiempo, la proporción de sexos también cambió significativamente, desde un predominio de hembras a un predominio de machos, en relación con un mayor desarrollo residencial. Esta tendencia sugiere que los paisajes urbanizados pueden representar territorios de menor calidad, ya que las hembras suelen ocupar hábitats de invernada de mejor calidad que los machos. Estos resultados sugieren que la urbanización podría afectar negativamente a las poblaciones invernantes de F. sparverius en esta región y se debería investigar como un posible factor que contribuye al declive poblacional continental general, especialmente en la ruta migratoria oriental donde la urbanización es prevalente. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Objective: Suckermouth armored catfishes (SACs; Loricariidae) have invaded water bodies outside their native range globally. Population control methods, including removals and genetic biocontrols, may be enhanced through greater knowledge of sex discrimination, sex ratios, and potential sex bias among control methods. Methods: We investigated sexual dimorphism and population sex ratio for an invasive SAC population of Hypostomus sp. in the upper San Marcos River, Texas, USA, as a means of advancing ongoing management of the population. Result: Among 385 specimens obtained at random during a planned dewatering of a 100‐m reach of the river, the sex ratio was biased toward females (proportion of females = 0.60). Morphometric analyses of 105 females and 108 males based on a generalized boosted classification model revealed elongated dorsal and anal fins in males correctly classified sex for 83% of individuals (95% CI = 77–88%). Seven independent observers used results from the generalized boosted classification model to assign sex to 30 fish, with average accuracy of 72% (range = 43–83%). The accuracy of the model and validation exercises were highest for fish >240 mm total length, the estimated length of reproductive maturity. Conclusion: Morphometrics based on dorsal‐ and anal‐fin sizes can be used to infer sex externally from hundreds of SACs removed per year to evaluate long‐term population management success. Impact statementSuckermouth armored catfish have invaded freshwater ecosystems globally, prompting increasing interest in control of nonnative populations. We provide a model for predicting sex of individuals based on external features as a means of advancing existing or future control programs. [ABSTRACT FROM AUTHOR]

Objective: We estimated the difference in mortality between mature male and female Vendace Coregonus albula based on a large data set of catch samples from 25 locations in Finland. We then used this estimate and age distribution data from Lake Etelä‐Konnevesi to illustrate how the sex ratio (females per one male) might decrease as the average age of spawners increases during a several‐year‐long period of recruitment failure. Methods: We estimated mortalities first from sex‐specific age–ln(catch) curves and second from the average age‐specific proportions of different sexes. Result: The estimate of the additional mortality of males was around 0.2–0.4, depending on the method of estimation, and assumed true proportions in the population at age 1 (two growing seasons), when Vendace reaches sexual maturity. When using the additional mortality estimate and age distribution data from Lake Etelä‐Konnevesi, the hypothetical sex ratio in the most extreme year was even as skewed as four females per one male. Conclusion: If the lack of males per female spawner during a population decline reduces the per capita recruitment success of females, this is a depensatory density‐dependent effect, the Allee effect. This phenomenon may partly explain the rapid population collapses and contribute to 2‐year cyclicity typical of the dynamics of Vendace populations. Impact statementIn the short‐lived coregonid fish Vendace, the mortality of males is considerably higher than that of females. During a period of low recruitment, this leads to a strongly skewed sex ratio, with female dominance in the spawning stock. Population decline accelerates if the increase in female dominance during stock decline reduces reproduction success (Allee effect). In stock assessment, attention should be paid to the sex ratio of the spawning stock, not just the spawner biomass. [ABSTRACT FROM AUTHOR]

Harlequin Duck (Histrionicus histrionicus) is a small sea duck that winters in coastal waters and breeds on fast-moving mountain streams in western North America. Because of its dependency on streams and coastal near-shore habitat with healthy macroinvertebrate populations, population trends of this species can be used as an indication of healthy freshwater and marine ecosystems. From 1995 to 2020 we conducted roadside surveys for Harlequin Ducks on the Bow River in Banff National Park, Alberta. We calculated the population's trend by modelling maximum annual count, which showed a population decline over the 25 years of 3.3% per year. The trajectory varied over time: a relatively stable population from 1995 to 2005, a steep decline until 2011, then stabilising at a much lower level with a slight rebound in recent years. The predicted number of ducks from our state-space model closely tracked the maximum number of ducks observed in annual counts. During stable or slightly increasing population estimates the male:female (M:F) ratio fluctuated considerably but stayed high (1.4:1 and 1.3:1, respectively), and during the period of steep population decline the M:F ratio was at its lowest (1.1:1). This declining population trend is concerning because it is occurring in a protected area, but it is similar to data from other studies in the Rocky Mountains and at the coastal wintering area, suggesting that causes may not be solely due to issues on the breeding streams. [ABSTRACT FROM AUTHOR]

The goal was to compare fissurectomy with mucosal advancement flap anoplasty to fissurectomy alone in the surgical treatment of anal fissure. This study included patients who underwent surgery in 2019 for solitary, idiopathic, non-infected, posterior anal fissure, after failure of medical treatment. The choice to perform advancement flap anoplasty was based on surgeon preference and did not depend on the fissure itself. The main endpoint was the time to relief of pain. Of 599 fissurectomies performed during the study period, 226 patients (37.6% women, mean age 41.7 ± 12.0 years old) underwent fissurectomy alone (n = 182) or associated with advancement flap anoplasty (n = 44). The two groups differed as to their sex ratio (33.5 vs. 54.5% women, P = 0.01), body mass index (25.3 ± 4.0 vs. 23.6 ± 3.9, P = 0.013) and Bristol score (3.2 vs. 3.4, P = 0.038). Time to relief of pain, time to disappearance of bleeding and time to healing were 1.1 (0.5–2.3), 1.0 (0.5–2.1) and 2.0 (1.1–3.6) months, respectively. The rate of healing was 93.8% and the complication rate was 6.2%. The differences between the two groups for these outcomes were not statistically significant. The risk factors associated with absence of healing were age ≥ 40 years (Odds ratio (OR): 3.84; 95% CI, 1.12–17.68) and pre-surgical duration of fissure < 35.6 weeks (OR: 6.54; 95% CI: 1.69–43.21). Mucosal advancement flap anoplasty does not provide any added value to fissurectomy alone. [ABSTRACT FROM AUTHOR]

This study aims to investigate the gonadal growth and gonads qualitative color assessment of the sea urchin Paracentrotus lividus in the Southeastern (SE) Mediterranean coast off Egypt. A total of 1895 sea urchins were collected between 2017 and 2018, and their reproductive biology parameters were determined. The gonadosomatic index with the histological analysis revealed that P. lividus has two spawning seasons (spring – autumn). Females and males have four maturity stages; recovery, growing, mature, and spent. Mature oocytes and sperms were observed during autumn, winter, and spring, while nutritive phagocytes dominated the tissue of both ovaries and testes in the summer season. The sex ratio (F: M) was male-biased (1: 1.2). The smallest observed size of mature males was 19.10 mm TD (test diameter), whereas the calculated L 50 was 26.2 mm. In females, the smallest observed size of a mature individual was 22.70 mm TD, and the calculated L 50 was 33.5 mm TD. The qualitative color assessment of the gonads revealed the dominance of excellent and acceptable color throughout the year (83.93%), with maximum value during the resting and recovery periods, while, the occurrence of unacceptable color was linked to the maturation and spawning periods. The present findings would assist the decision makers to propose management strategies and regulations on the harvesting of P. lividus off the Egyptian Mediterranean coast. [ABSTRACT FROM AUTHOR]

Copyright of Economic History Research / Investigaciones de Historia Económica is the property of Asociacion Espanola de Historia Economica 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 Trivers-Willard hypothesis predicts that parents in good condition are positively biased towards sons, while parents in poor condition are positively biased towards daughters. An extensive literature testing this hypothesis has accumulated in the last five decades. We take stock of results concerning humans in a systematic review, which yielded 87 articles, reporting a total of 821 hypothesis tests. A p-curving analysis did not reveal a pattern of p -values consistent with p-hacking. Effects are consistent with the Trivers-Willard hypothesis overall. We then went on to check whether there was a difference between sex ratio and post-birth investment. Theoretical work suggests that, the conditions under which the Trivers-Willard hypothesis is verified should be more restrictive in the case of post-birth investment than for sex ratio. We explored this question in two ways and obtained mixed results. We put forward recommendations for future studies that aim to further assess the validity of the Trivers-Willard hypothesis or mechanisms subtending it, and we discuss the implications of different ways of measuring parental status and investment. [ABSTRACT FROM AUTHOR]

A total of 300 freshwater mussels Lamellidens marginalis were sampled from the Ratargul Freshwater Swamp between December 2020 and November 2021 to investigate the relationships between length, weight, soft tissue wet parameters, sex ratio, condition indices, gonadal histology, and hydrological features of swamp forest habitat. The shell length and shell weight varied between 5.00 and 9.50 cm and 12.26–78.96 g respectively. The length at maturity L m was recorded as 5.98 cm and the calculated value of χ2 suggested a dominant female stock at the study site (P < 0.05). The relationship between different morphometrics of Lamellidens marginalis and environmental parameters exhibits a very weak regression coefficient value (P < 0.05), suggesting a weak effect of seasonality on the growth metrics. Previtellogenic and vitellogenic oocytes were observed in the ovary, and mature spermatids were found in the testes in samples collected in the rainy season. [ABSTRACT FROM AUTHOR]

The objective of this research was to determine the degree of use of the natural resource (blue crab-Callinectes sapidus) in the Ciénaga Grande of Santa Marta (CGSM), in order to generate biological information of interest for the responsible management of the natural resource. A quantitative study was developed. Data is processed through frequency and percentage measurements for each variable (sex, shell length- Lca, shell width- Abel, maturation), The data is processed through frequency measurements and percentages for each variable, regression graphs, frequency tables to know the size structure. 2346 specimens collected, presenting 47% of the catches below the average size at maturity. In 2018 there were increases in catches with a ratio of 9:2; while in 2021 the largest Abel (9.55cm), carapace length in centimeters-Lca (5.74cm) and weight (106gr) were recorded, that they probably present a moderate risk of exploitation. [ABSTRACT FROM AUTHOR]

Adult mortality is often the most sensitive vital rate affecting at‐risk wildlife populations. Therefore, road ecology studies often focus on adult mortality despite the possibility for roads to be hazardous to juvenile individuals during natal dispersal. Failure to quantify concurrent variation in mortality risk and population sensitivity across demographic states can mislead the efforts to understand and mitigate the effects of population threats. To compare relative population impacts from road mortality among demographic classes, we weighted mortality observations by applying reproductive value analysis to quantify expected stage‐specific contributions to population growth. We demonstrate this approach for snapping turtles (Chelydra serpentina) observed on roads at two focal sites in Ontario, Canada, where we collected data for both live and dead individuals observed on roads. We estimated reproductive values using stage‐classified matrix models to compare relative population‐level impacts of adult and juvenile mortality. Reproductive value analysis is a tractable approach to assessing demographically variable effects for applications covering large spatial scales, nondiscrete populations, or where abundance data are lacking. For one site with long‐term life‐history data, we compared demographic frequency on roads to expected general population frequencies predicted by the matrix model. Our application of reproductive value is sex specific but, as juvenile snapping turtles lack external secondary sex characters, we estimated the sex ratio of road‐crossing juveniles after dissecting and sexing carcasses collected on roads at five sites across central Ontario, Canada. Juveniles were more abundant on roads than expected, suggesting a substantial dispersal contribution, and the road‐killed juvenile sex ratio approached 1:1. A higher proportion of juveniles were also found dead compared with adults, and cumulative juvenile mortality had similar population‐level importance as adult mortality. This suggests that the impact of roads needs to be considered across all life stages, even in wildlife species with slow life histories, such as snapping turtles, that are particularly sensitive to adult mortality. [ABSTRACT FROM AUTHOR]

Unusual wildlife mortality events provide a unique opportunity to collect information on demographics, disease, and body condition in affected wildlife, which may be useful for informing oil spill damage assessments and future spill responses. In November 2007, the Cosco Busan Oil Spill occurred in San Francisco Bay, California, a globally important wintering area for waterfowl. The spill resulted in the mortality of scoters Melanitta spp. and scaups Aythya spp., species that have declined significantly over recent decades. We examined the demography (sex and age ratios) and prevalence of grossly apparent disease (acanthocephalan parasite infection and mycotic disease) in 288 Surf Scoters M. perspicillata, White-winged Scoters M. deglandi, Greater Scaup A. marila, and Lesser Scaup A. affinis killed in the oil spill. The proportions of females and juveniles in examined Surf Scoters was unexpectedly high (0.98:1, females:males, 0.73:1 juveniles:adults) for this species with normally strong male- and adult-biased populations. This disproportionate mortality of female Surf Scoters could result in a greater population impact on this female-limited species, suggesting a mechanism for steep declines in San Francisco Bay scoter numbers in the years after the Cosco Busan oil spill. Significantly greater rates of acanthocephalan infection in juvenile vs. adult Surf Scoters indicated a possible interaction between acanthocephalan parasitism and juvenile-biased mortality in our sample. Birds that died during rehabilitation had significantly greater rates of mycotic disease (10% infected) than birds found dead in the field (3%), indicating that infections began or worsened during rehabilitation. Greater Scaup had proportionally greater rates of infection with mycotic disease (26% of individuals) than other species, indicating that they may be particularly susceptible to the disease. We encourage the documentation of demographics and disease as a regular part of future responses to oil spills, or other mortality events, to gain insight into population impacts and improve rehabilitation efforts of affected populations. [ABSTRACT FROM AUTHOR]

Cisco (Coregonus artedi) support an evolving commercial roe fishery in Wisconsin waters of Lake Superior. To monitor trends in spawning cisco abundance, fishery managers recently began estimating adult biomass and exploitation using fall hydroacoustic surveys, which were combined with gill net surveys to inform apportionments of acoustic data. The gill net survey design consisted of paired top-suspended and bottom-set gill nets, but only the sex ratios from top nets are currently used with the hydroacoustic surveys due to an assumption that cisco in Lake Superior are pelagic spawners. However, the vertical sex distribution of cisco during spawning aggregations has been described as dynamic, with males becoming more bottom-oriented throughout the spawning season. We used multilevel aggregated binomial regressions to: 1) determine if there is bias between top and bottom gill net catches of cisco for either sex and if it changes throughout the spawning season, 2) evaluate how the vertical distribution of males and females may create bias in sex ratios used to estimate exploitation, and 3) explore the effect that maturity (i.e., gonadal development) has on vertical distribution during spawning aggregations. We identified sex-specific bias in vertical catch location that has the potential to bias estimates of sex ratio, and the source of this bias may be attributable to maturity driven changes in behavior. These findings highlight a need for caution when relying on gill nets to apportion cisco sex ratios during spawning aggregations and provide support for a non-pelagic alternative hypothesis of spawning behavior. [ABSTRACT FROM AUTHOR]

There are multiple sources of microplastic contamination in freshwater aquaculture areas, such as water inputs, use of plastic farming tools and weathering of discarded plastics, leading to microplastic contamination of aquaculture environments, but microplastics in freshwater aquaculture areas are still limited. In our study, we investigated the distribution of microplastics (MPs) in the aquaculture water, sediments and crabs during the growth cycle of crabs with different culture modes. The results show that from May to October, MPs in surface water first increased and then decreased, which is related to water evaporation and river water recharge caused by local hot and sunny weather. The concentration of microplastics in surface water reached a maximum of 9.25 items/L in September and 0.34 items/g-dry weight in sediment in June. The MPs in the sediments, although relatively stable, fluctuated due to river water replenishment. The number of detected MPs in male crabs was higher than that in female crabs, 17.96 ± 6.23 and 16.71 ± 4.45 items/individual, respectively. Crabs of different sexes were not selective for the color of MPs. The abundance of microplastics in different tissues of river crabs was in the order of foregut > hindgut > gill > hepatopancreas, whereas they were not detected in muscles. There were microplastic uptake and excretion behaviors during the growth culture cycle of river crabs. The microplastic amount was higher in the early stage and then showed a dynamic change of decreasing and then increasing. The number of MPs was higher in culture modes with different sex ratios, especially in male-dominated culture modes, which may be related to the more frequent activities of male crabs when the male ratio is high. This study provides useful information to understand the accumulation of microplastics in cultured hairy crabs and the source sinks and transportation of microplastics in artificial freshwater aquaculture in China. • The abundance of MPs in crabs increased with the increase of male crabs. • During the life cycle, the abundance of MPs in water increases and then decreases. • Local weather and human activities can affect microplastic abundance in ponds. • The abundance of MPs in male crabs was higher than t in female crabs. [ABSTRACT FROM AUTHOR]

BACKGROUND Age misreporting affects population estimates at older ages. In Brazil, every citizen must be registered and show an identity document to vaccinate against COVID-19. This requirement to present proof of age provides a unique opportunity for measuring the oldest-old population using novel administrative data. OBJECTIVES To offer critically assessed estimates of the Brazilian population aged 80 and older based on data from the vaccination registration system (VRS). To uncover discrepancies between the number of vaccinated oldest-old people and the projections used to estimate target populations for COVID-19 vaccination. METHODS We calculate data quality indicators based on data from the VRS - namely, 100+/80+ and 90+/80+ population proportions, sex ratios, and the Myers blended index - and compare them to those based on data on target populations from Brazilian censuses and demographic projections, and from Sweden - a country with high-quality data. We also estimate vaccination coverage ratios using population projections adjusted to excess deaths as the denominators. RESULTS Requiring documentation reduces age heaping, age exaggeration, and sex ratios marginally. However, it cannot solve the problem of the misreporting of birth dates due to the absence of long-standing birth registration systems in Brazil, particularly in the northern and central regions. In addition, we find a mismatch between the projected populations and numbers of vaccinated people across regions. CONCLUSIONS Despite improvements in data quality in Brazil, we are still not confident about the accuracy of age reporting among the oldest old in the less advantaged Brazilian regions. The postponement of the 2020 census reduced the ability of authorities to define the target populations for vaccinations against COVID-19 and other diseases. CONTRIBUTIONS This is the first study to compare population estimates for the oldest old in administrative data and census data in Brazil. Age misreporting resulted in discrepancies that may have compromised the efficacy of the COVID-19 vaccination campaign. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Field-Naturalist is the property of Ottawa Field Naturalists' Club 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: The Lake Superior Kiyi Coregonus kiyi is an understudied species being considered for reintroduction into Laurentian Great Lakes where it no longer occurs. Herein, we provide descriptions of Kiyi reproductive biology with the intention of guiding potential gamete collections for propagation. Methods: Data were collected on Kiyi spawning timing, spawning locations, spawning season catch rates, length at sexual maturity, sex ratios, fecundity, egg size, and larval occurrences in Lake Superior from 1996–2021. These data were compared to observations made a century prior in Lakes Michigan, Ontario, and Superior. Result: Contemporary Kiyi spawning occurred between late December and late January when surface water temperatures cooled to <4°C. Spawning Kiyi were caught almost exclusively in 38.1‐mm stretch mesh, as compared to larger meshes (50.8–76.2 mm). Capture depths for developing, ripe, running, and spent female Kiyi were similar and ranged from 82 to 221 m. Fifty percent of female and male Kiyi were classified as sexually mature at ~150 mm total length. Fecundity estimates ranged from 1,578 to 6,720 eggs/female. Mean diameter of unfertilized eggs was 1.7 mm. Recently hatched larval Kiyi were collected at the surface during May–July at 62 of the 113 locations sampled throughout the lake in 2019. Conclusion: Our work suggests that Kiyi gamete collection efforts from mid‐December through January using 38.1‐mm gill‐net panels set at bathymetric depths of at least 100 m would maximize the collection of spawning Kiyi and reduce the bycatch of other Coregonus species. Future research questions include the following: (1) "Do Kiyi form spawning aggregations at specific spawning areas, or do they spawn indiscriminately across the lake?"; (2) "Do Kiyi spawn near the bottom or up in the water column?"; (3) "What is the relationship between fall lake overturn and Kiyi spawn timing?"; and (4) "Could summer larval and age‐0 Kiyi collections provide an opportunity for establishing a captive broodstock?" Impact Statement: Kiyi historically occurred in Lakes Huron, Michigan, Ontario, and Superior. Today it occurs only in Lake Superior. This study provides contemporary information on Kiyi reproductive biology with respect to where, when, and how to collect spawning Kiyi in Lake Superior for potential use in propagation and reintroduction programs. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Many ecological questions can be answered only with data from hundreds or even thousands of individuals. In some taxonomic groups, such as snakes, the availability of those data is rare due to low population densities and/or the difficulties in collecting them. Hence, studies on the population structure of snakes are still relatively scarce compared to other zoological groups. In this study, we had the opportunity to analyze the population structure from an unusually large sample of the Pampean water snake Helicops infrataeniatus. The specimens were collected through a flood event caused by excessive rainfall related to an El Niño period in southern Brazil. Although H. infrataeniatus is a common species in the study area, no ecological data regarding its population structure are available so far. Therefore, the main goals of this study were to (1) determine sex ratios, (2) test for sexual dimorphism, and (3) identify the ventral polymorphism in this population. We analyzed 672 individuals (46.4% females, 53.6% males; 50.2% were classified as adults, 48.6% juveniles, and 1.3% hatchlings). The total body length (ToL) ranged from 18.4-77.4 cm for females, and 19.7-67.0 cm for males, tail length (TaL) was 4.5-21.9 cm and 5.8-21.5 cm; sub-caudal scales were 55-73, 74-92, and weight was 2.2-191.0 g, 2.3-93.3 g. Highly significant differences were detected in the number of sub-caudal scales and the TaL:ToL ratios between females vs. males tested via analysis of covariance (ANCOVA), suggesting the presence of sexual dimorphism. Regarding the ventral spotting patterns, 38.0% of individuals had trilinear, 36.0% - intermediate, and 26.0% - checkered color patterns. Besides this, 63.0% of the individuals had a reddish ventral coloration, 25.0% - yellowish, and 12.0% - both colors. No correlation was found between ventral polymorphism and sex or age class. The results presented herein offer the first robust snapshot of the population structure of H. infrataeniatus. [ABSTRACT FROM AUTHOR]

Brook Trout Salvelinus fontinalis have been introduced across the western USA, where the species competes with and often replaces native salmonids. Nonnative Brook Trout are difficult to eradicate; thus, new removal strategies are needed. One novel methodology couples the partial suppression of wild Brook Trout with the replacement of MYY Brook Trout (males with two Y chromosomes). If MYY fish survive to reproduce with wild female Brook Trout, their progeny will be 100% male, which eventually shifts the sex ratio and theoretically extirpates the population. However, the effectiveness of this approach depends on survival and reproduction of MYY fish relative to the surviving wild conspecifics. From 2018 to 2020, we annually removed an estimated 45.7% of wild Brook Trout from three streams in New Mexico and stocked fingerling MYY Brook Trout (mean TL = 94 mm; range = 61–123 mm) targeting 50.0% of wild annual abundance estimates. Annual survival for MYY and wild Brook Trout was similar in Leandro Creek (MYY = 0.63 and wild = 0.63) and Rito de los Piños (MYY = 0.37 and wild = 0.46) but differed in Placer Creek (MYY = 0.28 and wild = 0.75). During spawning, we evaluated the reproductive potential of MYY Brook Trout by comparing the percentage of sexually mature male Brook Trout comprised of MYY fish to the percentage of hybrid (MYY × wild) F1 progeny. By the second spawning season (2019), MYY fish comprised 59.8, 50.4, and 34.5% of milt‐producing Brook Trout, which resulted in 55.1, 33.3, and 0% hybrid progeny in Leandro Creek, Rito de los Piños, and Placer Creek, respectively. We demonstrated that MYY fish exhibit similar vital rates compared with wild conspecifics in two of three streams; however, differences among streams highlights unforeseen variables that influence MYY survival and reproduction. The study offers promising results of the MYY approach for potentially eradicating unwanted Brook Trout populations. [ABSTRACT FROM AUTHOR]

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico 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.)

Growing awareness has been raised to minimize the misuse of pesticides by searching for alternative pest control methods including insect parasitoids. The use of the egg parasitoid belonging to the genus Trichogramma to beat economic insect pests is gaining increasing attention, however, there are multiple factors can have a substantial influence on the performance and the efficacy of parasitoid wasps. The current study was created to evaluate the impact of host egg age on some biological parameters for Trichogramma evanescens wasps. Thirteen ages of Sitotroga cerealella eggs with six hours intervals were affirmed; the youngest age was zero hr (newly laid eggs) and the oldest one was 72 hrs. The % emergence, sex ratio, longevity, and the emergence of first generation (F1) of the T. evanescens were investigated. The obtained data showed that as the age of S. cerealella eggs proceed, a drastic reduction in adults emergence occurred. Females emerged from newly laid host eggs lived for the longest time when females were still alive 94.00 hrs representing eight hours more longevity compared to females emerged from 72 hrs eggs. The female percentage also was influenced by the host egg age, it declined from 62.54% in fresh eggs to 59.25% in 72 hrs old eggs. In F1 progeny, fewer emerged parasitoid wasps were recorded with the aging of host eggs. It could be concluded that the % emergence, longevity, sex ratio, and F1 progeny fitness of T. evanescens were largely hosted egg age-dependent. For effective and commercial mass production, newly laid eggs were recommended to obtain the maximum % adults' emergence can live a long time. [ABSTRACT FROM AUTHOR]

As most organisms, humans and other apes compete for access to fitness-determining resources and competition is expected to increase with the competitor-to-resource ratio. We use 23 years of behavioural data on five wild groups from the two gorilla species which live in different socioecological environments, to test if female gorillas compete simultaneously for food, mates and/or protectors. Females were more aggressive to each other in medium-sized groups (∩ − shaped relationship) and when the groups contained more females but fewer males (lower sex ratio). Contrarily, female-female aggression was not influenced by the operational sex ratio and female mating activity. Hence, our results support the competition for food and protectors hypotheses but cast doubt on the competition for mates hypothesis. Yet, despite female western gorillas (Gorilla gorilla gorilla) experiencing higher monopolization potential of food and a lower abundance of food and males, they did not exhibit higher aggression rates than female mountain gorillas (Gorilla beringei beringei). Altogether, these results suggest that female competition for males outside the mating context is not unique to humans and might have common evolutionary origins in humans and other apes. [ABSTRACT FROM AUTHOR]

BACKGROUND In China, a key feature of demographic transition is the abnormally high sex ratio, resulting in a shortage of brides. In addition, depressive symptoms among Chinese adolescents have risen sharply in the last decade, and among these adolescents, boys in rural areas are most likely to be depressed. OBJECTIVE In this study, we investigate the phenomenon of depression in a large number of rural boys. We hypothesize that upon perceiving the strong competition in the local marriage market, rural parents tend to increase educational investment to improve their sons' relative standing in the market, thereby leading to high pressure and depression among rural boys. METHODS By leveraging variations across counties and cohorts, we constructed a difference-indifferences model featuring rich fixed effects to absorb invariant confounding factors and cohort trends across provinces. To ensure the exogeneity of sex ratios, we studied the first children in families, in cognition of the randomness of the first child's gender. CONCLUSIONS Empirical evidence suggests that high sex ratios motivate rural parents to elevate their educational expectations of and tangible and intangible investments in their sons, invariably increasing performance pressure and lowering academic performance, thereby deepening mental depression. CONTRIBUTION Our study contributes to multidisciplinary theories, such as son preference, competitive motive, and tiger parenting theory. Moreover, our findings have relevant implications: (1) A population control policy combined with a son-preference culture induces several unanticipated negative consequences. (2) The unrestrained educational investment is in disagreement with human capital outcomes. [ABSTRACT FROM AUTHOR]

The veined Rapa whelk, Rapana venosa (Valenciennes, 1846), have a significant commercial value in Turkey. This study was carried out between December 2013 and November 2014 in the Black Sea. R. venosa was collected to determine the reproductive cycle, the gonadosomatic index, gonad index. Monthly variation in gonad development stages revealed that R. venosa has an annual reproductive cycle and long gonadal activity period. Spawning occurred mainly between May and July and peaked in July and in September. The gonad development stages of males and females differed significantly (P<0.05) between months. In November, 1 out of 30 samples were found as a hermaphrodite, containing both sperm and eggs in the same area. Male individuals were dominant during the study period (1.0:2.4 female: male). [ABSTRACT FROM AUTHOR]

INDIA IS THE FOURTH BIGGEST TYRE MAKER GLOBALLY AFTER CHINA, EUROPE AND THE UNITED STATES. GROWING DEMAND FOR AUTOMOBILES HAS MADE THE INDIAN TYRE INDUSTRY FUNDAMENTALLY STRONG. EQUITY INVESTORS ARE ALSO INVESTING THEIR MONEY IN THE TYRE SECTOR STOCKS. HOWEVER, MANY SECTORS ARE UNDERPERFORMING DUE TO THE GLOBAL PANDEMIC AND ECONOMIC SLOWDOWN. THIS STUDY USES RATIO ANALYSIS TO EXAMINE THE PERFORMANCE OF TYRE SECTOR COMPANIES IN INDIA. FROM THE ANALYSIS, WE FOUND THAT IN THE YEAR 2020, BECAUSE OF COVID-19 PANDEMIC, THE PERFORMANCE OF MANY COMPANIES HAS AFFECTED, AND THE INDUSTRY'S DEBT INCREASED. DEBT EQUITY RATIOS OF ALL COMPANIES EXCEPT BALAKRISHNA ARE LESS THAN ONE, WHICH IS A GOOD SIGN. THE NET PROFIT AND OPERATING PROFIT RATIO OF BALAKRISHNA COMPANY ARE VERY HIGH COMPARED TO OTHER SELECTED COMPANIES. HOWEVER, THE ASSET TURNOVER AND FIXED ASSET TURNOVER RATIOS OF GOODYEAR COMPANY ARE BETTER THAN ALL OTHER SELECTED COMPANIES. REGARDING WORKING CAPITAL, THE INVENTORY TURNOVER OF RUBFILA AND THE DEBTOR TURNOVER RATIO OF APOLLO COMPANY ARE BETTER THAN OTHER COMPANIES. [ABSTRACT FROM AUTHOR]

The paper proposes using the sex ratio at birth (SRB) as a "population test" to study the impact of extreme exogenous shocks on demographic status of historical populations. 53,355 baptismal records from the years of 1801-1920 for Detva population, located in the Upper Hungary, contemporary Slovakia, were examined for the purpose of the study. The sex ratios at birth were calculated as the proportion of the number of male live births to the number of female live births. Our results show a decline in the values of SRB in the years when the population was exposed to wars, including Napoleonic wars, civil wars, and the First World War, and economic crises caused by natural disasters and crop failures. These events could have contributed to poverty, deterioration of living conditions, insecurity, social and psychological instability, loss of property and family members, and could have been the source of psychological stress to which pregnant mothers were exposed. [ABSTRACT FROM AUTHOR]

Double diapering may help to maintain a baby's hips in flexion and abduction posture, but the efficacy in facilitating hip maturation has never been verified. We investigated whether double diapering results in greater improvement of the alpha angle in newborn babies. This prospective study enrolled newborns with Graf type IIa immature hips and assigned them to the double-diaper or single-diaper group by the day of birth in a week. Parents were instructed on proper hip positioning, except for diapering. Change in the alpha angle from newborn to 1 month after birth, rate of improvement to bilateral Graf type I hips in 1 month, and number of ultrasound examinations and orthopaedic clinic visits in the first year were compared between the two groups. Seventy newborns with 102 type IIa hips were included from January to December 2017. They were allocated to the double-diaper group (n = 33) and single-diaper group (n = 37). With a comparable sex ratio, gestational age, and newborn alpha angle, the double-diaper group had a greater increase of alpha angles in 1 month than the single-diaper group (+7.9° vs. +5.2°, t-test, p = 0.011). Twenty-eight babies in the double-diaper group (84.8%) and 20 babies in the single-diaper group (54.1%) improved to having bilateral Graf type I hips (chi-square test, p = 0.006). Under the same clinical management pathway, subsequent clinical visits and hip ultrasounds before 1 year were significantly reduced in the double-diaper group. Double diapering enhances hip maturation and reduces clinical costs in newborns with physiological immature hips, but the therapeutic role for hip dysplasia requires further study. [ABSTRACT FROM AUTHOR]

To contribute to more balanced perspectives on sub-municipal population change in sparsely populated areas (SPAs), this paper closely examines a local pocket of growth in a shrinking Northern Swedish municipality. Integrating Swedish register data with in-depth qualitative insights, the geographic study examines patterns and processes of uneven local population dynamics linked to life course migration. This is done through a socio-spatial cluster analysis containing, first, 15 aggregate socioeconomic variables for sub-municipal areas, and then individual characteristics like birth countries, age groups, sex ratios, educational attainment, and employment status. A Foresight approach and interviews with locals, municipal officials, and incoming lifestyle migrants complement this. Studying these individuals' practical compromises regarding housing, income, and leisure at sub-municipal levels helps in overcoming fallacies in population change research at broader regional levels, and illustrates the limits of relying solely on quantitative demographic change indicators. The paper shows that urban traits in the municipal centre and rural natural amenities around a dogsledding trail combine to attract and retain different population groups. This adds to population change studies and shows that municipal administrative centres in SPAs are not necessarily growing while other villages are declining, and that population redistribution at the municipal level does not automatically imply the movement of people to municipal centres from a municipality's minor villages. • This paper analyses migration flows at sub-municipal levels. • We integrate quantitative and qualitative approaches. • Microurbanisation in SPAs is connected with various migration flows. • Population redistribution did occur in places' immediate context. • People make practical compromises between urban and rural traits. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

This study aimed to evaluate and compare seasonal variations of Hippocampus reidi population structures in two Brazilian coastal areas. Samples were collected from the rocky shores of Urca and Duas Irmãs Island by freediving along fixed transects. All seahorses observed in the study were recorded, measured, and identified by sex and reproductive stage. Seahorse behavior and fish depth were also registered. All individuals were photo-identified to estimate recapture rates. Holdfast used by seahorses was also recorded. Results showed low densities at both sites; sex ratio and juvenile/adult proportion did not appear to vary with season. The seahorse height differed between the two areas but did not vary with season nor sex. Seahorses in both sites were found in shallow waters (i.e. up to 4 meters), and the depth did not vary by season nor sex. Males were more frequently recaptured than females in both areas. All seahorses were reproductively active year-round, peaking at rainy periods in both areas. The seahorses were more often recorded while resting and seemed to anchor on seaweed. Though in different bays, seahorse population structure and seasonality appeared similar. These data provide useful baseline data for future population assessments. [ABSTRACT FROM AUTHOR]

The present study examined reproduction biologies of 336 and 384 individuals of native Pagellus erythrinus and non-native Nemipterus randalli species captured using trammel nets in Marmaris Bay on a monthly basis from January to December 2018. Total length, weight and sex ratios in N. randalli obtained by trammel net were 9.2-21.2 cm (mean±SD; 16.2±2.43), 9.15-142.63 g (mean±SD; 61.23±29.12), 1:0.41, respectively. First maturity lengths for female and male individuals of N. randalli were 13.11 cm and 15.55 cm, respectively. Linear relationship between total length and fecundity of the species whose fecundity was 37785-55200 (mean±SD; 46172±7450) was calculated as F=1445.1TL+34612 (R²=0.75). For P. erythrinus species, total length and weight and sex ratios were 10.2-28.5 cm (mean±SD; 18.50±3.37), 10.27-307.14 g (mean±SD; 88.53±48.57) and 1:0.64, respectively. The first maturity lengths of P. erythrinus were 12.69 cm in females and 14.83 cm in males, respectively. The fecundity of the species was found to be 34503-125102 eggs (mean±SD; 65863±25258). Linear relationship between total length and fecundity was F=10289TL-179 788 (R²= 0.76). [ABSTRACT FROM AUTHOR]

Sex is an important parameter to consider when studying population dynamics and movement ecology, for example, though sex determination is often difficult in young birds of sexually monomorphic species, with large biometric overlap between sexes. We aimed at determining the sex of first-calendar-year (1cy) Carrion Crows, in order to study temporal trends in sex ratio. We performed molecular sexing of a sample of 48 females and 45 males, creating a statistical framework to confidently discriminate sexes using four morphometric variables. Although biometrics overlapped between sexes, we developed a discriminant function which separated the sexes with high accuracy (88%). Then we applied this discriminant function to biometrics obtained from all 1cy individuals captured, to determine their sex. We found a female-biased overall sex ratio of the captures: female Carrion Crows might therefore be more numerous than males, or more prone to enter traps. There were significant variations in sex ratio between years, but not between months. [ABSTRACT FROM AUTHOR]

The Laurentian Great Lakes of North America support a large and profitable freshwater fishery, but one continuously beset by parasitism from the invasive sea lamprey (Petromyzon marinus). Despite being the life stage that inflicts damage to the fishery, therefore necessitating a bi-national control program, our knowledge of juvenile sea lamprey ecology is poor and their response to control efforts are not assessed. Incidental capture of juvenile sea lamprey by commercial fishers is one means to collect data on this enigmatic life stage, and in Lake Huron such data have been collated since 1967. Here, we explore incidental captures of juvenile sea lamprey and their hosts from northern Lake Huron between 1987 and 2017 (n = 33,246 observations) to address four objectives. Firstly, we document collection efforts by fishers to provide historical context to the dataset. Secondly, we pose and test a series of questions related to fishery encounter, host selection, growth, distribution, and sex ratio to highlight how these types of data can be informative regarding juvenile sea lamprey ecology. Results presented here could be used to develop biological hypotheses to be addressed in future work. Thirdly, we directly assessed whether juvenile sea lamprey capture data could be useful in corroborating trends observed in adult sea lamprey abundance and wounding, as well as in identifying abundance and wounding hotspots. Lastly, we summarize research and outreach efforts that have benefited from the capture of juvenile sea lamprey in recent years. [ABSTRACT FROM AUTHOR]

Bat swarming in Siberia and the Russian Far East has not yet been studied. Therefore, the purpose of the present research was to obtain information about bat swarming (species composition, sex ratio and age structure) as it relates to mating at several sites in Siberia. The study of bat swarming was carried out in July–September 2015, 2016 and 2017 in the eastern Palaearctic at the entrances to three large karstic caves: Okhotnichya, Mechta and Dolganskaya Yama, located in the Baikal rift zone. We captured 1,604 bats belonging to seven species: Plecotus ognevi, Murina hilgendorfi, Myotis petax, Myotis sibirica, Myotis ikonnikovi, Myotis [frater] longicaudatus and Eptesicus nilssonii. In all swarming sites P. ognevi predominated (40–85%). The second most abundant species was M. hilgendorfi (except for Mechta Cave, where high numbers of M. petax were observed). In all the caves, males predominated (70–88%), except for Dolganskaya Yama Cave in September where the sex ratio was close to 1:1. Adult individuals were more numerous than juveniles, which reached the maximum proportion (30%) in Dolganskaya Yama Cave in September due to the inflow of juvenile females of P. ognevi. The maximum body mass and BCIvp (body condition index taking into account observed to expected body mass) of adult males of dominant species were recorded in September for P. ognevi in Dolganskaya Yama Cave and M. hilgendorfi in Dolganskaya Yama and Okhotnichya caves. Based on the observations, it appears that the peak of mating of P. ognevi and M. hilgendorfi occurs in mid-August, when the ratio of males and females was 7:3. Moreover, in the case of P. ognevi the peak of mating is apparently more dependent on climatic conditions than in M. hilgendorfi. The abundance of species during the swarming season and hibernation in the same caves differed — P. ognevi and M. hilgendorfi occurred as singletons in winter, and Myotis spp. (mostly M. sibirica) predominated. Our results support the hypothesis that swarming is typical for bats of the temperate zone throughout the entire Holarctic (Europe, North America and Asia). [ABSTRACT FROM AUTHOR]

[Display omitted] • Pareumenes quadrispinosus is a common species using trap nests in North Vietnam. • The nests are built from mid-April to last October. • The number of provisioned cells in a nest is one to four. • Brood cells were provisioned with caterpillars. • It is multivoltine, with two alternative life histories and overlapping generations. Nests of Pareumenes quadrispinosus (de Saussure, 1855) were obtained at Me Linh Station for Biodiversity (323 nests) and Tam Dao Town (283 nests), Vinh Phuc Province, as well as at Phu Luong, Thai Nguyen Province (9 nests) and Kim Boi, Hoa Binh Province (62 nests). The wasps nested in segments of bamboo canes and reed stems, 5 to 18 mm in internal diameter. Each nest consisted of a linear series of one to four cells, separated by mud partitions. Brood cells were provisioned with caterpillars and eggs were attached to the ceiling of the cells by thin threads. The life history and sex ratio of this species nesting in trap nests in North Vietnam were recorded from mid-April to last October. The species is multivoltine, with likely up to four generations per year. It has two alternative life histories (diapause and direct development) and overlapping generations. The sex ratio is strongly female-biased. Only 46% of the provisioned cells were successful; the others were damaged by nine parasitoid species or died during development for unknown reasons. [ABSTRACT FROM AUTHOR]

Rainbow Smelt Osmerus mordax are a small anadromous species that is native to the northwest Atlantic Ocean, and their populations have declined rangewide. A small, mid‐channel survey fyke net is annually deployed to collect demographic information on Rainbow Smelt in several rivers in Massachusetts. Understanding the effectiveness of this fyke net for providing representative data on the spring spawning run is essential for accurate population assessment. To evaluate this effectiveness, we deployed an experimental fyke net that spanned the river channel concurrently with the survey fyke net in the Fore River, Massachusetts, from 2009 to 2012. The survey net CPUE increased as the total number of fish increased, but survey net catches are highly variable at lower daily abundances. The differences in the size distributions were slight and only significant for females in 1 of 4 years. The sex ratios were generally the same between both nets. These findings suggest that while fyke nets might not be ideal for monitoring rivers with very small populations and/or in wide river reaches, catches in larger populations should generally reflect the overall population demographics. [ABSTRACT FROM AUTHOR]

Plant production under climate changes requires unique treatments to overcome the detrimental effects of abiotic stress, such as water deficiency stress. Silicon (Si) has many beneficial effects, especially in plants subjected to different types of stress. Hence, Si foliar application was used to study its potential effects on boosting osmolytes content, activity of antioxidant enzymes, growth of vegetative and flowering organs, and yield of squash plants (Cucurbita pepo L.) under deficit irrigation. Two field experiments were conducted during the winter seasons of 2019 and 2020 at the Experimental Farm, Faculty of Agriculture, Ain Shams University, Egypt. Three concentrations of Si at 0, 2000 and 4000 ppm in the form of monosilicic acid (H 4 SiO 4) under two levels of water irrigation at 80% of water holding capacity (WHC) as control and 50% of WHC as drought treatment. Drought treatment significantly reduced the growth parameters: shoot height, shoot fresh and dry weights, leaves number/plant, average leaf area, fruit setting and yield traits, and the physiological attributes: leaf relative water content (LRWC), total chlorophylls (SPAD), total soluble proteins (TSP) and catalase (CAT) activity. Meanwhile, significant increases in the concentrations of stress indicators (total free amino acids and proline) were observed compared to the control plants (80% WHC). Both rates of Si achieved marked increases in the vegetative growth, flowering, chlorophylls, LRWC, TSP, superoxide dismutase (SOD), CAT, peroxidase (POD) and polyphenol oxidase (PPO) activity, which in turn reflects on improving fruit setting %, total fruits, and yield of squash plants under well or deficit irrigation. Spraying the high level of Si (4000 ppm) was the most effective treatment that emended the adverse effects of drought. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effects of a newly synthesized sulfonamide compound, a phar-\maceutical raw material (2a), which has been found to inhibit carbonic anhydrase I and II isoenzymes, on some developmental properties of Drosophila melanogaster. The administration of substance 2a to D. melanogaster was carried out by feeding, based on the value of Ki and using three different doses (2.12 (j.1, 4.25 (j.1 and 8.5 JJ.1). The data were obtained from Fi and F2 generations. However, the substance was only applied to the parental individuals of the Fi generation, which did not lead to a toxic effect in the Fi generation but caused a decrease in the number of adult individuals and an increase in the number of abnormal individuals of the F2 generation at the highest dose (8.5 JJ.1). The substance was only administered to parental individuals, which prevented direct contact of the F2 generation with the substance. Therefore, the effects on the F2 generation at the highest dose may be related to hereditary mutations. There was no deviation in the sex ratio in both generations, which can be interpreted as evidence of the absence of a sex-related effect of substance 2a. An unexpected result was the increase in the number of adult individuals in the positive control group (10 mM NaAsCh) of the F2 generation. All these results are indicative that this new sulfonamide may be a promising therapeutic agent in the future. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology 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 quest for spouses among rural men in China has become increasingly arduous, resulting in a growing number of older bachelors. However, the mechanisms driving the marriage squeeze in underdeveloped rural areas remain poorly understood. This study analyzes time-series data from 70 marital unions across 58 households in two geographically distinct villages in the Loess Plateau Region of China. The results indicate that marriage expenses and the subsequent financial burden on the bridegroom's household increased substantially from 1969 to 2018, particularly in the most recent decade, while the bride's household received the majority of marriage-related income. There has been an overall increasing trend in economic pressure induced by marriage expenses in both villages since 1979. A cohort of older bachelors has emerged in the hilly village, where rural males traditionally marry women from more remote, underdeveloped areas. Conversely, rural males in the tableland village can consistently find spouses from comparable geographical settings and have not yet emerged as older bachelors. This study concludes that the marriage squeeze manifests as dual pressures from economic and living conditions, and excludes economically disadvantaged males in harsh environments from the marriage market within the context of rural out-migration and the sex ratio imbalance. • Marriage expenses have increased substantially over the past five decades. • Poor rural males in harsh environments are susceptible to the marriage squeeze. • Marriage squeeze manifests as dual pressures from economic and living conditions. [ABSTRACT FROM AUTHOR]

Copyright of Clio. Femmes, Genre, Histoire is the property of Belin Editeur 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.)