State of the pacific oyster Crassostrea gigas (Thunberg, 1793) population in the Losos Bight (Sakhalin Island) in 2013–2020

The state of the aggregation of Pacific oyster Crassostrea gigas (Thunberg, 1793) in the Losos Bight (Aniva Bay) in 2013–2020 was assessed. For now, this aggregation has been in depression as a result of intense fishing. The abundance of the aggregation of commercial individuals (shell height >120 mm) was poor two recent years. The total stock estimated is 31.5 t; the commercial stock – 4.7 t.

Anton Chekhov’s Sakhalin Island: An Ongoing Commentary

A study of the currently existing translations of Anton Chekhovs Sakhalin Island (From Travel Notes) (Luba and Michael Terpak - 1967, Brian Reeve - 1993) shows that the reason for some errors in translated texts is not always due to the negligence of translators, which is so clearly noticeable in the first translation, but rather in the incomprehensibi- lity for foreigners of some realia in the original text. Reference to two available Сommentaries on Sakhalin Island, by M.L. Semanova (1985) and M.S. Vysokov (2010), as well as to the works of other Chekhov scholars, did not give the sought-after explanations of certain vague excerpts from the book. Those obscure excerpts are also poorly understood by the Russian readership. In particular, we are talking about Chekhovs mention of the use of a naval rope in the surgical department (Chapter VII) and the perception of the status of a class feldscher/paramedic (Chapter XII). The author of the article offers her own commentary on difficult-to-understand passages and thus fills the gap that has arisen. Conclusions are drawn about the need to continue to provide Chekhovs Sakhalin Island with commentaries and notes. Such commentary should serve two purposes. Its linguistic and cultural character should help to clarify the realias not only for representatives of a foreign linguistic culture - in order to prevent gross errors in translations, but also for the present-day Russian reader, separated from the time when A.P. Chekhovs book was written by almost one hundred and thirty years.

Body condition of gray whales (Eschrichtius robustus) feeding on the Pacific Coast reflects local and basin-wide environmental drivers

A small subset of the Eastern North Pacific gray whale population does not make the full migration from wintering grounds in Mexico to feeding grounds in the Bering, Chukchi and Beaufort seas and instead feed along the Pacific Coast between northern California and northern British Columbia – this group is known as the Pacific Coast Feeding Group (PCFG). We evaluated the body condition of PCFG whales observed in northern Washington and along Vancouver Island to evaluate how body condition of gray whales changes within and between years. We found that PCFG gray whales improve body condition through the feeding season and at varying rates by year and that they have variability in their body condition at the start and end of each feeding season. The inclusion of environmental factors, particularly the Pacific Decadal Oscillation (lagged two years) and September kelp canopy cover along the Washington coast (lagged one year), drastically improved the ability of a multiple regression model to predict average whale body condition for a given year as compared to models without environmental factors included. A comparison of our findings to a previously published study on body condition of gray whales at Sakhalin Island, Russia highlight the differences of life history strategy between a group of whales with a long migration (Sakhalin whales) and those with a short migration. Whales feeding at Sakhalin Island gain body condition quicker and more predictably to a good body condition by the end of the feeding season than the whales we studied in the PCFG. Photogrammetry may be an effective method for monitoring the effects of climate change on PCFG gray whales.

Biodiversity of the flora of vascular plants of the Makarovsky Nature Reserve on Sakhalin Island

The article is devoted to the research results concerning the flora of vascular plants of the Makarovsky Nature Reserve situated in the middle part of Sakhalin Island. Nowadays, 407 species of vascular plants have been identified on its territory, and 26.8 % of the total number of taxa known on the island. Among them, 13 species of rare plants included in the Red Data Book of the Sakhalin Region have been identified. The structure of the leading families and genera is indicated, the flora is analyzed by life forms, geographical elements and ecological-cenotic groups.

Recreational resources of the coasts of the southern part of Sakhalin Island and the southern part of the Crimean Peninsula (problems and solutions)

The possibilities of recreational-oriented use of the coast are studied on the basis of the trend analysis in the development of the coasts and regional features of the exploitation of the coasts of Sakhalin Island and the Crimean Peninsula. It is shown that the loss of recreational capacity of coastal territories is the result of both man-made and natural components of development. The conclusion is made about the degradation of a significant part of the recreational resources of the coasts. The concept of a model of integrated use and sustainable development of natural mineral resources, hydrogeological and recreational resources is proposed.

The first results of the seismic monitoring system of the Solntsevsky open pit coal mine area (on Sakhalin Island)

In 2021, work began as a part of the implementation of the decision of the protocol of the Sakhalin branch of the Russian Expert Council on earthquake prediction, seismic hazard and risk assessment dated October 6, 2020 on detailed monitoring in the area of active coal mining at the Solntsevsky open pit coal mine (Sakhalin Island). New points of seismic monitoring were installed directly in the area of the open pit coal mine. Integration of real-time data received from the points in real time into a unified seismic monitoring system in the Sakhalin Region was ensured. The results of registration of seismic events of various origins since the commissioning of the stations are presented. A significant increase in the accuracy of the determined epicenters and the possibilities of determining earthquakes and industrial explosions has been noted. The results of the monitoring system for studying the landslide process in the area of the open pit coal mine, as well as the probable factors that caused the landslide, are shown. The developed monitoring system allows for representative registration of seismic events with ML ≥ 0.8 in the immediate vicinity of open pit coal mine, which makes it possible to control blasting operations with increased accuracy, as well as weak and possible induced seismicity formed as a result of a constant technogenic impact on the subsoil.

Temperature regime of the Daginsky thermal springs (Sakhalin Island) during their reconstruction in 2019-2021

The article presents the results of studies of the temperature regime of the Daginsky thermal springs. Daginsky thermal springs are the most famous and visited on Sakhalin Island (Russia). In the fall of 2019, their reconstruction and arrangement of the surrounding landscape began. As a result of the reconstruction of the main thermal springs, their hydrological and temperature regime was violated, the water temperature dropped. In 2020, in the springs most popular with visitors (Aleksandrovsky, Tsentralny, Mechta), the temperature became several degrees lower, which led to the termination of their use. In 2021, after the completion of the design of the spring bath and the surrounding area, the temperatures increased. In April 2021, the temperature of the Patriot spring was 40.5 °C, the Partizan spring 38–39 °C, the Central spring 36–39 °C, the Aleksandrovsky spring 34.6–36.0 °C, the Mechta spring 34.4 °C (at the bottom up to 45.5 °C), Molodost spring 35 °C (at the bottom up to 37–41.3 °C).

Identification of disjunctive dislocations as one of the parameters for estimating a territory seismicity of North Sakhalin

The north of Sakhalin Island is characterized by frequent earthquakes and many disjunctive dislocations. One of the catastrophic earthquakes occurred in the settlement of Neftegorsk. The level of modern technologies makes it possible to track the change in environmental parameters accompanying dangerous natural processes with a high degree of certainty. The article proposes an interpretating technology for disjunctive dislocations detecting, which differs from the existing ones with the complex use and summation of satellite image data using image processing methods widely applied in “computer vision”. The study aims to compile and describe a map of discontinuous faults of the village of Neftegorsk, located in the northern part of Sakhalin Island, using the developed decoding technology and geophysical data. Methods: Identification methods used in the work: 1) methods of primary image processing (correction, transformation, resolution change, cropping, visualization); 2) a set of “contextual” and “autonomous” methods of lineament analysis, with the help of which a series of images is processed (canny, erosion, Hough’s algorithm); 3) methods for constructing maps of discontinuous faults (summation, sequential linking). Results. Using the developed technology, a map of discontinuous faults in the area of the Neftegorsk earthquake was constructed. The implementation of the technology makes it possible to provide the monitoring data on discontinuous faults to organizations that are engaged in seismic zoning, construction and operation of objects for various purposes, including mineral deposits.

A new species of the genus Proctogastrolaelaps McGraw & Farrier (Acari: Melicharidae) from the Far East of Russia, and contributions to knowledge of this genus

We describe a new mite species from the Far East of Russia—Proctogastrolaelaps subsolanus Joharchi & Marchenko sp. nov. (Acari: Melicharidae). The new species was collected from soil-litter on the shores of the Tunaycha Lake and Sea of Okhotsk in Sakhalin Island. The important morphological characteristics of the genus Proctogastrolaelaps are revised.