Testing for Geographic Variation in Survival of Spectacled Eider (Somateria fischeri) Populations in Chukotka, Russia and the Yukon-Kuskokwim Delta, Alaska

Information on variation in survival among geographically distinct breeding populations can produce valuable insights about the population dynamics of a species. The Yukon-Kuskokwim Delta sub-population of Spectacled Eiders in Alaska decreased precipitously between the 1950s and 1990s. Causes for this decline are unknown but may be attributed to low female survival due to predation and lead exposure on the breeding grounds. From 2014 to 2015, we compared annual survival probabilities of Spectacled Eiders on Kigigak Island in the Yukon-Kuskokwim Delta, Alaska, and Ayopechan Island in the Chaun Delta, Chukotka, where similar field protocols were implemented. A Cormack-Jolly-Seber maximum likelihood approach was used to estimate apparent survival (φ) and recapture probability (p) from mark-resight data. We tested a) whether Russian and Alaskan sub-populations differed in their survival rates, b) whether survival varied annually, and c) whether survival followed an increasing or decreasing trend over time at either site. We found no evidence for differing survival between the two breeding areas when mean survival across years was compared, and we did not find strong evidence for a linear trend in survival over time at either site. Furthermore, our data supported models with annually varying survival at Kigigak Island and constant survival at Ayopechan Island. Sample size constraints precluded estimates of annual survival at Ayopechan Island. Our finding of no difference in mean survival between sites lends support to the idea that survival may be a function of conditions on the wintering grounds.Les données en matière de variations de survie chez des populations nicheuses géographiquement distinctes peuvent donner un précieux aperçu de la dynamique des populations d’une espèce. La sous-population d’eiders à lunettes du delta Yukon-Kuskokwim, en Alaska, a chuté abruptement entre les années 1950 et les années 1990. Nul ne connaît les causes de ce déclin, mais elles pourraient être attribuables au faible taux de survie des femelles en lien avec la prédation et l’exposition au plomb dans les aires de reproduction. De 2014 à 2015, nous avons comparé les probabilités de survie annuelle des eiders à lunettes sur l’île Kigigak, dans le delta Yukon-Kuskokwim, en Alaska, et sur l’île Ayopechan, dans le delta Chaun, au Tchoukotcha, où des protocoles d’étude similaires sur le terrain ont été adoptés. La méthode du maximum de vraisemblance Cormack-Jolly-Seber a servi à estimer la survie apparente (φ) et la probabilité de recapture (p) à partir de données de marquage et de relocalisation. Nous avons tenté de déterminer a) si les sous-populations de la Russie et de l’Alaska avaient des taux de survie différents, b) si les taux de survie variaient d’une année à l’autre et c) si le taux de survie affichait une tendance à la hausse ou à la baisse au fil des ans à l’un ou l’autre des sites. Nous n’avons trouvé aucune preuve justifiant le taux de survie différent aux deux aires de reproduction au moyen de la comparaison des moyennes de survie au fil des ans, et nous n’avons pas trouvé de preuve importante permettant de déceler une tendance linéaire au fil des ans en matière de survie à l’un ou l’autre des deux sites. De plus, nos données ont permis d’étayer des modèles ayant des taux de survie annuels variables à l’île Kigigak et des taux de survie constants à l’île Ayopechan. Des contraintes en matière de taille d’échantillons ont empêché de faire l’estimation des taux de survie annuels à l’île Ayopechan. Le fait que nous n’ayons pas trouvé de différence entre les moyennes de survie des deux sites soutient l’idée selon laquelle la survie peut être tributaire des conditions des aires d’hivernage.Данные об изменении выживаемости в географически обособленных гнездовых популяциях позволяют понять тенденции динамики популяций рассматриваемого вида. В период с 1950-х по 1990-е гг. наблюдалось резкое снижение численности гнездовой популяции очковой гаги в дельте рр. Юкон-Кускоквим, предположительно обусловленное низкой выживаемостью взрослых самок из-за сильного пресса хищников и отравления птиц свинцом в районах гнездования. Мы сравнивали показатели ежегодной выживаемости взрослых самок очковой гаги на о. Кигигак, дельта рр. Юкон-Кускоквим, Аляска, США и на о. Айопечан, дельта рр. Чаун-Пучевеем, Чукотка, Россия. Идентичные полевые протоколы были разработаны и применены в обоих районах исследования. Метод максимального правдоподобия Кормака-Джоли-Себера использовался для оценки ежегодной выживаемости (φ) и вероятности обнаружения (p) птиц по данным повторных отловов. Мы проверяли: а) существование статистически значимых различий в выживаемости самок очковой гаги чукотской и аляскинской популяций в период с 2002 по 2015 гг.; б) межгодовые колебания ежегодной выживаемости; в) наличие тенденций повышения или понижения выживаемости с течением времени в каждой из популяций. Мы не выявили статистически достоверных различий в выживаемости самок из двух районов гнездования, а так же не обнаружили тренда выживаемости со временем ни в одной из популяций. Данные, которыми мы располагаем, позволили оценить ежегодную выживаемость самок на о. Кигигак и, по причине недостатка данных, среднюю межгодовую выживаемость самок на о. Айопечан. Наши выводы о том, что выживаемость самок одинакова в обеих популяциях, позволяют предположить, что на выживаемость очковых гаг в меньшей степени влияют условия гнездовых территорий, чем комплексные условия акватории зимовки

When Ice Turns to Water: Forest Fires and Indigenous Settlements in the Republic of Sakha (Yakutia)

In recent years, forest fires have covered many parts of the Republic of Sakha (Yakutia). The fires often threaten populated areas and Indigenous communities as well. In 2020–2021, the fires caused enormous economic and environmental damage and the exact amount is yet to be fully calculated. Concerns about the sheer scale of carbon emissions into the atmosphere were widely discussed by world media. Social scientists of the Republic of Sakha (Yakutia) raised the following questions: how do Indigenous communities live in a condition of constant threat from annual forest fires? What environmental, social, and economic challenges do they face, what do they fear, and what are their expectations? We reviewed Indigenous traditional knowledge related to fire management and firefighting techniques and analyzed Indigenous peoples’ perceptions of changes in the ecological balance of water resources and permafrost. The authors also discuss the causes of forest fires, connections with industrial and transport development, and social consequences. The article is based on 2010–2021 field studies

When Ice Turns to Water: Forest Fires and Indigenous Settlements in the Republic of Sakha (Yakutia)

In recent years, forest fires have covered many parts of the Republic of Sakha (Yakutia). The fires often threaten populated areas and Indigenous communities as well. In 2020–2021, the fires caused enormous economic and environmental damage and the exact amount is yet to be fully calculated. Concerns about the sheer scale of carbon emissions into the atmosphere were widely discussed by world media. Social scientists of the Republic of Sakha (Yakutia) raised the following questions: how do Indigenous communities live in a condition of constant threat from annual forest fires? What environmental, social, and economic challenges do they face, what do they fear, and what are their expectations? We reviewed Indigenous traditional knowledge related to fire management and firefighting techniques and analyzed Indigenous peoples’ perceptions of changes in the ecological balance of water resources and permafrost. The authors also discuss the causes of forest fires, connections with industrial and transport development, and social consequences. The article is based on 2010–2021 field studies

Preparation and Selection of Best-Performing Fluorescent-Based Tracers for Oil and Gas Downhole Applications

Cost-efficient tracers with fast and simple detection and quantification methods at low detection limits via on-site detection is a current industrial target for state-of-the-art tracer tests. To bridge the gap between the desired tracer properties and detection limits, we developed a broad spectrum of robust and cost-efficient fluorescent tags to innovate the current reservoir management practices. We engineered new tracers and extended tracer test applications for on-site real-time well-drilling monitoring to label drill cuttings as they are made at the drill-bit face to improve drill-cuttings depth correlation. These developed fluorescent tracers not only have the low detection limits of fluorescent spectroscopy techniques but also allow for automated detection at minimal concentrations of 0.025–0.037 mol.%. These developed tracers allow us to detect the real-time drilling depth, thereby enhancing hydrocarbon recovery. Thus, the reported innovative fluorescent-based tracing approach would (1) reduce drilling depth correlation uncertainty, (2) optimize well placement, and (3) maximize oil production

Impact of natural fires on the vegetation cover of steppe and forest-steppe zones (European part of Russia, Middle Volga region)

The effect of natural fires on the vegetation cover of steppe and forest-steppe zones in the south-east of European Russia (the middle course of the Volga River) has been evaluated. The research used methods of studying biosystems at organism, species, population and cenotic levels. The study revealed the possibility of regrowth of aboveground plant parts after fires, changes in the population structure of species, and resistance of populations and zonal plant communities to the effects of natural fires. The most vulnerable among zonal vegetation types are pine forests, feather-grass and petrophytic steppes. Frequency, intensity and area of natural fires in the Middle Volga region cause significant changes in the structure of vegetation cover and reduction of biodiversity. The results obtained in the study of the impact of fires on vegetation can be used in the planning and implementation of environmental and reforestation measures

Additional file 2: of Karyotype features of trematode Himasthla elongata

Supplementary methods. (DOC 16 kb

Additional file 3: Figure S2. of Karyotype features of trematode Himasthla elongata

Ag-staining of H. elongata nuclei. Nuclei with more than two Ag-NORs detected are shown in B, C, E, F, G. Scale bar – 10 µm. (TIF 4102 kb

Additional file 1: Figure S1. of Karyotype features of trematode Himasthla elongata

Flow cytometry profile of 2C peaks for the species indicated. X axis - the relative pripidium iodide (PI) fluorescence intensity at FL3 channel; Y-axis, the number of events. (TIF 88 kb

Additional file 4: Figure S3. of Karyotype features of trematode Himasthla elongata

Correspondence of Ag-NOR-staining and rDNA FISH signals at aneuploid metaphase spread of H. elongata. A – metaphase spread. B – karyotype of the metaphase spread shown in A. Asterisks mark the correspondent chromosomes with rDNA FISH signals at (main text, Fig. 6). Scale bar – 10 µm. (TIF 481 kb

One-Pot Synthesis of Au@SiO₂ Catalysts: A Click Chemistry Approach

Using the copper-catalyzed azide–alkyne cycloaddition “click” reaction, a library of triazole amphiphiles with a variety of functional polar “heads” and hydrophobic or superhydrophobic “tails” was synthesized. The amphiphiles were evaluated for their ability to stabilize small Au nanoparticles, and, at the same time, serve as templates for nanocasting porous SiO₂. One of the Au@SiO₂ materials thus prepared was found to be a highly active catalyst for the Au nanoparticle-catalyzed regioselective hydroamination of alkynes