The Kamchatka Volcanoes Nature Park Network, together with scientists from the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences and the Vitus Bering KamSU, conducted research on salmon populations living in isolated mountain reservoirs of the Bystrinsky Park. In the mountains of the central Sredinny Range (middle range) of the Bystrinsky Park, cold lakes are located near the snow line in harsh climatic conditions. These reservoirs are covered with ice for most of the year (more than 9 months), and even in summer there are frosts. The shallow waters along the banks are practically lifeless, and the transparency of the dark blue water reaches 10 meters. As part of a comprehensive study of the ecosystems of the Bystrinsky Park, scientists continue to study lakes that have become inaccessible to river salmon due to isolation by rockfalls, lava flows, or rapids on the outflowing river. “Among the reservoirs of interest to us are such objects as Bolshoe Goltsovoe, Snezhnoe, Avotia, Galyamaki. The lakes vary in size, but they are all characterized by great depths, very low ecosystem productivity, and freezing of the littoral,” said Daria Panicheva, head of the laboratory at the Vitus Bering KamSU. Scientists have discovered that these isolated reservoirs were inhabited by Malma char before the barriers appeared. Despite the harsh conditions, the populations of these lake char are thriving. This became possible due to their evolutionary specialization. "All the populations under consideration are characterized by a slowdown in somatic growth while maintaining the rate of morphological differentiation and delayed sexual maturation. This phenomenon is called dwarfism," explained Grigory Markevich, an employee of the IEE RAS. The char from subnival lakes are similar in appearance to their large ancestors and do not have a morphological reduction. They live up to 9 years, but grow very slowly, rarely reaching 20 centimeters in length. Their metabolism is aimed at saving energy and accumulating fat for the maturation of reproductive materials. Spawning fish are distinguished by a very bright nuptial plumage, their fertility does not exceed 200 eggs. Due to their small size, they cannot bury their eggs in nests, but throw them into cracks between stones. "Dwarfism is widespread in vertebrates. Its possible cause is considered to be the inhibition of cellular signals during development due to a change in the structure of thyroid hormone receptors. This variant of the development of char seems interesting and requires verification in light of our discovery of the leading role of thyroid hormones in biological speciation in salmonids,” explained Evgeny Yesin, an employee of the Institute of Ecology and Evolution of the Russian Academy of Sciences.

From June 15 to June 25, 2024, a business trip of Arina Raldugina and Danila Sotnikov to the Buzuluksky Bor National Park took place within the framework of the cooperation agreement between the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences and the Buzuluksky Bor National Park. During the trip, Arina Olegovna and Danil Andreevich collected samples of microscopic crustaceans (Cladocera and Copepoda) and algae, as well as representatives of parasitic invertebrates localized in the eyes and intestines of fish from different types of water bodies in the Samara and Koltubanka river basins. All collected material will be analyzed using morphological and molecular genetic methods in accordance with modern standards adopted in the taxonomy of each studied group. In 2024, the main focus is planned to be on the qualitative determination of the species composition of algae and invertebrates in the samples and analyzing the most common groups (desmids and diatoms, cladocerans, copepods and shell crustaceans, larvae of some insect groups). Based on the data from the material processing, preliminary lists of species and a working collection of microscopic algae and invertebrates of the Buzuluksky Bor National Park will be prepared by December 2024. The results obtained will be presented in collaboration with the staff of the National Park at one of the conferences on the biodiversity of aquatic ecosystems held in Russia in 2025.

Photo by IEE RAS A team of experts left Severo-Kurilsk on a yacht and headed to the northwest of the Sea of ​​Okhotsk in the Shelikhov Bay area. The specialists will study the summer habitats and possible wintering grounds of bowhead whales. Studying habitats and monitoring are the main tasks of the expedition. The vessel will move along the coast, carefully examining all the bays and inlets along its way. The fact is that to date, there are isolated and scattered results of studies of bowhead whales of the Sea of ​​Okhotsk in this water area. In 2021-2023, scientists conducted expeditions in the bays of the Shantar region, where the key summer habitats of whales known today are located. Based on the results, recommendations were prepared to minimize anthropogenic impact on animals. Last year, for the first time in many years, data was collected on whales in the Shelikhov Bay area. In order to develop and implement effective measures to protect the species, it is necessary to obtain complete data on the condition of animals in these areas. Photo by IEE RAS Another important task for scientists will be taking biopsy samples from marine mammals. Genetic analysis will help to understand the whales' "registration" - whether scientists have encountered them before, this is how isolated the Shelikhov Bay group is. Taking a piece of skin from whales (biopsy) is carried out by certified specialists using a special crossbow and is safe for the animal. The expedition participants plan to assess the whales' food supply in this area. To do this, they will use a plankton net to collect samples of invertebrates, which will be delivered to Moscow for further analysis. The expedition will end in mid-August in Magadan. The data will then be analyzed. The project to preserve bowhead whales in the Sea of ​​Okhotsk is being implemented by the Nature and People Foundation in partnership with the Institute of Ecology and Evolution of the Russian Academy of Sciences, the Siberian Wellness Company Foundation “The World Around You”, the company JSC “UTLC ERA” and the Ilya Trukhanov Clinic “KIT”. Photo by Ilya Trukhanov About the Okhotsk Sea population of bowhead whales The Okhotsk Sea bowhead whales occupy the southernmost part of the range of this species. Their entire life cycle takes place in Russian waters. Predatory whaling in the 19th century almost completely exterminated this population; in the mid-20th century, they were considered extinct for a decade. Today, their numbers do not exceed 400 individuals. The Okhotsk Sea population of bowhead whales is listed in the Red Book of the Russian Federation, where it is assigned the highest priority of urgency and priority of environmental measures taken and planned for being implemented. The bowhead whale is one of the focus species of the federal project "Conservation of biological diversity and development of ecological tourism" of the national project "Ecology". The population of bowhead whales in the Sea of ​​Okhotsk is declining and is under threat of extinction. Due to climate change and the shortening of the ice season, whales in the summer mainly go to the shallow bays of the coldest Shantar region in the western part of the Sea of ​​Okhotsk, while  a small number also enter Shelikhov Bay in the northeast. Here they are protected from killer whales, but in shallow waters they face a potentially even more serious threat - the economic activity, the intensity of which is constantly growing.

Fig. 1. Yulia Davydova and her students defending their diploma theses. On June 14, 2024, the Federal State Budgetary Educational Institution of Higher Education "Kozma Minin Nizhny Novgorod State Pedagogical University" held the defense of diploma theses completed by bachelors of the Biology and Chemistry profile under the supervision of PhD in Biology, Associate Professor of the Department of Biology, Chemistry, Ecology and Teaching Methods Yulia Davydova (Fig. 1). The scientific consultant of student projects from the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences was PhD in Biology, Senior Researcher of the Laboratory of Ecology of Aquatic Communities and Invasions Anna Neretina. And the muse that inspired students throughout the academic year was the cladocera Daphnia. Artist Alexey Litvinov prepared comics that humorously play out the process of hunting for this species (Fig. 2). In essence, comics are a didactic development aimed at increasing the cognitive motivation of schoolchildren to study microscopic water bodies and to develop an interest in research activities in general. Fig. 2. Comics by Alexey Litvinov. Another biology student also showed a creative approach to studying these Cladocera: poet and musician Vladislav Vorobyov dedicated a song to daphnia, performed by Kristina Chukhnina. Песнь дафнии: Взгляни скорей в глаза мои: В глазок простой и сложный… А сердце рвется из груди Прозрачно-невозможное. Ты сеть планктонную бросай В мой омут чисто-черный! Ты душу мне свою отдай, Отдай и будь покорным… Ты покорись красе моей, Красе прозрачно-нежной. Взгляни же на меня скорей, Не стой на побережье! Возляг с сачком со мной во мхах Навстречу бурной страсти: Ведь торакальных ножек взмах - Твой путь к мечте и счастью! Song of The  Daphnia is available in Russian as a standard performance, rock, adaptation for schools, lyrical, and pop. Стандарт, в рок-стиле, адаптированную версию для школьников, лирическую, в поп-стиле. They even filmed a music video with the participation of Yulia Davydova and Polina Tyutyaeva. The song, the video and the comics are parts of a single whole: they served as multimedia tools for teaching biology for the school educational master class "The World through the Lens of a Microscope: Cladocera and Methods of Studying Them". The master class was held by a creative team of students during the summer natural science school "Wake the Einstein within You" at the Pedagogical Technopark "M.V. Lomonosov Quantorium" of Minin University (Fig. 3). Fig.3. Schoolchildren and students at the master class "The World through a Microscope Lens: Cladocera and Methods of Studying Them". The story did not end there, and the creative team working on the artistic rethinking of methodological approaches to involving schoolchildren in science has expanded! The lyrics of the song about daphnia were revised by Ivan Rogozhkin, editor-in-chief of the Energovector.com Portal. Взгляни скорей в глаза мои Сквозь окуляр Олимпус, А сердце рвется из груди Прозрачное, как импульс. Ты сеть планктонную бросай В мой омут чисто-черный Ты душу мне свою отдай И будь судьбе покорный. Ты удивись красе моей, Красе прозрачно-нежной. Взгляни-ка на меня скорей На отмели прибрежной. С сачком приди-ка в камыши Открытиям навстречу, Болотным газом подыши, А я тебя здесь встречу. Ты удивись красе моей, Красе прозрачно-нежной. Взгляни-ка на меня скорей На отмели прибрежной. Взгляни скорей в глаза мои. Ты сеть планктонную бросай. Ты душу мне свою отдай И будь судьбе покорный. Here are the links to the newer versions: first, second, third, fourth, fifth. The team of the Laboratory of Ecology of Aquatic Communities and Invasions congratulates the graduates of Minin University on the successful defense of their diploma theses, and wishes patience and inspiration to Yulia Yuryevna Davydova in the difficult task of integrating science and education, as well as popularizing scientific knowledge! You too can join the art of hunting for Daphnia! To do this, just take a scoop-net and other inventory for collecting samples from the Laboratory of Ecology of Aquatic Communities and Invasions and, following the instructions, go in search of adventure! Summer has just begun! Fig. 4. Making the next version of a net for catching Daphnia (July 2022 – Yes, Alexey Alekseevich hasn’t made nets himself in a long time)). P.S. By the way, some scoop-nets were made personally by the Corresponding Member of the Russian Academy of Sciences, Chief Researcher Alexey Alekseevich Kotov, and the construction of scoop-nets is a process as exciting and creative as writing musical or artistic compositions. Create, dream, dare!

Fig.1. Nanofluids, i.e. liquids containing nanoparticles, have unique properties, in particular significantly increased thermal conductivity, but their widespread use is still limited due to the poor study of their properties. Photo taken from the site: https://www.azonano.com/article.aspx?ArticleID=6268 Nanofluids are liquids that contain particles (or agglomerates of particles) up to 100 nm in size. Nanofluids have unique physical and chemical properties, such as significantly increased thermal conductivity compared to the carrier liquid. Currently, nanofluids are actively used in engineering, biology, pharmacology and other industries. Nanofluids are actively used in heat removal and temperature regulation in various devices, including laboratory devices used in biological experiments. Along with the experimental study of nanofluids in the laboratory, mathematical and computer modeling plays a significant role. It allows testing various hydrophysical and temperature regimes for a wide range of parameters without using expensive experimental equipment. In this scientific work, researchers from the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences and Al-Joufa University (Saudi Arabia) used mathematical modeling to study the spatial distribution of velocities and temperatures of a nanofluid when the flow is excited by rotating a smooth disk. Mathematically, the original Navier-Stokes equations, which are usually used in modeling fluid dynamics, were simplified using similarity transformations (von Karman transformations). Then, the corresponding simplified equations of steady flows were solved numerically, i.e. using computer modeling. Copper nanoparticles were considered as colloidal particles forming the nanofluid. It was found that the most important parameter regulating the temperature regime is the proportion of copper nanoparticles in the liquid. It is hoped that the temperature and velocity fields found on the basis of calculations will soon improve the operation of various laboratory installations used in both biological and physical experiments, for example, to maintain the temperature regime of the experiment and the ability to quickly switch from one temperature regime to another. The results were published in the journal: Alkuhayli, N.A.M. and Morozov, A., 2024. Analysis of Heat Transfer for the Copper–Water Nanofluid Flow through a Uniform Porous Medium Generated by a Rotating Rigid Disk. Mathematics, 12(10), p.1555.

Russian scientists, under the leadership of Corresponding Member of the Russian Academy of Sciences Alexei Kotov, sequenced the mitogen of the Abrau sprat, a unique endemic fish of Lake Abrau (Krasnodar Territory). “Sausage fish” (as the original describer S. Myalatsky called it in 1928), or Abrau sprat, is a unique representative of freshwater herring, living only in Lake Abrau. The Abrau sprat differs from its closest relative, the Black Sea-Caspian sprat, in body proportions and some biological features. Until recently, it was believed (IUCN Red List, 2008) that this species had disappeared from the fish community of Lake Abrau and there was no data on its existence in recent decades (Red Book of the Russian Federation, 2021). When studying the zooplankton of the lake in 2019, several small herring fish, identified as Clupeonella abrau, were found in the plankton net as bycatch. To verify the accuracy of the definition, historical material from the collection of the Zoological Museum of the Zoological Institute of the Russian Academy of Sciences (collection 1938) was analyzed. DNA barcoding showed the identity of modern and historical samples of sprat from Lake Abrau. To clarify the phylogenetic relationships, the complete mitochondrial genome of the sprat was sequenced and annotated, which showed significant similarity with other Clupeonella. The “sausage fish” is a unique component of the ichthyofauna of the Lake Abrau natural monument, and at present this species has not disappeared from the fish community of the reservoir and is able to reproduce under current conditions. The study was attended by employees of the I.D. Papanin Institute of Inland Water Biology  RAS and the A.N. Severtsov Institute of Ecology and Evolution RAS. The work was published in the July issue of the journal Doklady Biological Sciences.

Photo: PJSC Lukoil A hundred years ago, hundreds of thousands of saigas lived in the Russian steppes, but by the early 2020s, only thousands remained. Over the 20th century, this species has become one of the most vulnerable on the planet. The Kommersant newspaper published a large article about how in recent years they have managed to stop the extinction of this amazing relict animal. Anna Yachmennikova, senior researcher at the Laboratory of Behavior and Behavioral Ecology of Mammals, A. N. Severtsov Institute of Ecology and Evolution RAS, told reporters about how animal monitoring occurs and about the implementation of the program. Part of the modern range of the relict antelope in Russia has been given protected status. Thus, in the habitat of the population of the North-Western Caspian Sea, the state natural biosphere reserve “Chyornye zemli” (Republic of Kalmykia) and the state natural reserve of regional significance “Stepnoy” were formed. “In the 50–60s, the number of saigas in the North-Western Caspian region reached almost 800 thousand animals, but in the last decades of the 20th century it rapidly declined. In 1998, it was about 150 thousand animals, in 2006 - 14-16 thousand, in the spring of 2011 it no longer exceeded 7 thousand individuals, and in the summer of 2019 it decreased to a catastrophic 5 thousand,” says the director of the state reserve “Chyornye zemli" Bataar Ubushaev. Prized trophy Photo: PJSC Lukoil The reason for the rapid decline in the population was both intensive economic activity and the increasing scale of hunting for this animal. “The prevailing view is that the main reason was the massive illegal hunting of saigas for the very profitable trade in horns,” says Bataar Ubushaev. In Soviet times, saiga hunting was so popular that the Saiga family of hunting rifles was named after the animal. They were developed in the 1970s specifically for shooting saigas - it was believed that the antelope should be fought because it destroys steppe crops. At one time, until about the mid-1990s, saiga hunting was also encouraged by global conservation groups: its horns served as an alternative to rhinoceros horn. Habitat area There are currently five saiga populations in the world. Two of them live in Russia - in the North-Western Caspian region in the Chyornozemelsky, Yustinsky and Yashkulsky regions of the Republic of Kalmykia, as well as in the Limansky district of the Astrakhan region. Another population, the Ural one, is transboundary: these animals move between Kazakhstan and the Left Bank of the Volga - Astrakhan, Volgograd, Saratov, and Orenburg regions. Natural causes also had their influence. “Saiga as a species is characterized by sharp fluctuations in numbers. During the 20th century, the saiga population of the North-Western Caspian region was on the verge of extinction three times. The fact is that if during the natural period of depression in the number of this antelope there is a powerful anthropogenic pressure, then the species may disappear completely,” says a senior researcher at the Laboratory of Behavior and Behavioral Ecology of Mammals at the A. N. Severtsov Institute of Ecology and Evolution (IEE) RAS Anna Yachmennikova. Disturbance of balance Photo: PJSC Lukoil The disappearance of the saiga also poses a threat to unique steppe and semi-desert ecosystems. The fact is that their sustainability depends on maintaining natural balance. “Steppes and semi-deserts are extremely complex ecosystems, consisting of a huge number of interconnected components. If you remove one from it, the others will also suffer. Thus, we can say that the saiga is one of the edificatory species for steppe and semi-desert ecosystems,” explains Bataar Ubushaev, director of the Black Lands Nature Reserve. The problems of preserving the biodiversity of certain biomes cannot be solved without preserving key species that play an important role in the functioning of ecosystems, adds Galina Kalmykova, state inspector of the Stepnoy nature reserve. “The saiga antelope is an important component of the biodiversity of the arid landscapes of Eurasia and the only antelope species found in Europe. In the biocenoses of the steppes and deserts of Russia, the saiga population plays a significant role, and its loss from the structure of ecosystems not only reduces the level of biodiversity, but also leads to their degradation,” she emphasizes. Renovating water sources and fighting steppe fires Photo: PJSC Lukoil Today, in Chyornye Zemli and Stepnoye, the conservation and reintroduction of saiga is carried out as part of LUKOIL’s corporate program for the conservation of biological diversity. It is part of the federal project “Preservation of biological diversity and development of ecological tourism” of the national project “Ecology”. An agreement on cooperation between LUKOIL and the Russian Ministry of Natural Resources was concluded in March 2020. The company developed an action plan for 2020–2024 with the assistance of the management of Chyornye Zemli and Stepnoye, together with the expert environmental and scientific community. “LUKOIL’s help cannot be overestimated. The funds that are allocated to the Stepnoy nature reserve starting in 2020 allow us to increase the number of security raids, carry out measures to prevent fires, and clear water sources,” states Galina Kalmykova, state inspector of the Stepnoy nature reserve. Over five years, as part of the implementation of the plan, large-scale work has been carried out: water carriers have appeared for rapid response in case of fires, old artesian wells have been cleared to organize water sources for wild animals. Fire-fighting equipment was purchased and monitoring towers were built. With the help of machinery and special attachments, the territories of the reserves were cleared of dry vegetation. Using plows, mineralized firebreaks were laid, which divided the protected areas into sectors. The roads have been leveled and cleared, which allows inspectors not only to move quickly when conducting security raids, but also to quickly arrive at places of possible fire. “The measures made it possible to reduce the dangerous impact of fires, one of the most negative factors for the saigas’ habitat,” emphasizes Galina Kalmykova. Saiga Day Photo: PJSC Lukoil The plan also includes the purchase of equipment - copters, binoculars, thermal imagers, camera traps, protective clothing for government inspectors, radio stations and cellular amplifiers, vehicles for patrolling the territory. This allows to quickly respond and prevent cases of poaching, and is also used for scientific purposes of monitoring and recording saigas. In addition, scientific and educational events are held as part of Saiga Day. “Thanks to funding, we can work closely with the local population, hold conversations with farmers about the need to comply with environmental legislation and explain their role in preserving both the saiga and the entire biodiversity of their native land,” notes Galina Kalmykova. Particular attention is paid to working with the younger generation: competitions, excursions are held, and volunteer events are organized. “Today, poaching has been completely eliminated in the reserve,” states Galina Kalmykova. How to count saigas Photo: PJSC Lukoil The positive effect of the four-year program is evidenced by the intensive growth of the saiga population - in December 2022 it amounted to 26.6 thousand individuals, which is more than five times higher than the data for 2018–2019. The assessment was carried out at the Institute of Ecology and Evolution of the Russian Academy of Sciences, calculations were carried out using satellite images using a neural network. “This is our first experience of using artificial intelligence to count animals in space images,” shares senior researcher at the institute Anna Yachmennikova. According to her, previously, counts were carried out from cars or small aircrafts, which had an extremely negative impact on saigas: cars violated the cover of vulnerable steppe ecosystems, and aircrafts sent animals into a panicked flight - there were cases of death from exhaustion. Moreover, such methods are not adequate for covering large areas at once. “We have been using satellite images to count saigas since 2012, but until now this has been done manually. Saigas are graceful antelopes, they are much smaller than an elephant or a walrus; manual counting of them is very difficult and takes a lot of time. Artificial intelligence has made it possible to carry out this work much faster, and the results can be used not only for statistics, but also for making operational decisions,” says Anna Yachmennikova. Stopping the depression Photo: PJSC Lukoil Even more impressive figures for the restoration of the saiga population are provided by the director of the Chyornye Zemli Nature Reserve, Bataar Ubushaev. According to him, at the end of 2023, the number of saigas in Russia was estimated at no less than 26–28 thousand individuals. For May 2024, taking into account young animals, the preliminary estimate is already 40 thousand individuals. “Thanks to the timely financial support of LUKOIL, we were able to stop the depression in the number of saigas, stabilize the situation and achieve a sustainable increase in the number of this unique animal,” sums up Bataar Ubushaev. Harmonious coexistence 2024 is the final year in LUKOIL’s current plan for the conservation and reintroduction of the saiga, but not the last in the history of this species’ struggle for survival. According to Anna Yachmennikova, it is now almost impossible to completely return the relict antelope’s entire historical range - most of it has long been occupied by humans. Therefore, the task for the future is to ensure the harmonious coexistence of the two species.

Fig. 1. Appearance of the Arctic alligatorfish from the Kara Sea: a) top view, b) bottom view, c) side view The Arctic alligatorfish Aspidophoroides olrikii is a member of the family Agonidae (Fig. 1) with a nearly circumpolar range. It is found in Arctic waters from the White Sea and the eastern part of the Barents Sea to the Beaufort Sea, in the adjacent North Atlantic off the coasts of western Greenland, the USA and Canada, and in the northern part of the Pacific Ocean from the Bering Strait south to Cape Navarin along the Asian coast and to mouth of the Yukon according to American. Despite its wide geographical distribution and the fact that this species is considered quite common, the available information on its ecology is extremely limited and fragmentary. Fig. 2. Density distribution of the Arctic alligatorfish in the Kara Sea in September 2019 depending on: a) depth, b) bottom temperature. Scientists from the P.P. Shirshov  Institute of Oceanology RAS, A.N. Severtsov Institute of Ecology and Evolution RAS, the Kamchatka branch of the Pacific Institute of Geography FEB RAS and the All-Russian Research Institute of Fisheries and Oceanography obtained new data on the spatial and vertical distribution, temperature characteristics of the habitat, size-age and size-sex structure, age and growth rate, size and age of puberty, fertility and food composition of the Arctic alligatorfish in the Kara Sea. Fig. 3. Typical catch of the Arctic alligatorfish in the Kara Sea in September 2019. Maximum catches of this species were recorded north of the Yamal Peninsula at depths of 18-21 m in the temperature range at the bottom from -1.49 to -0.96°C (Fig. 2). In trawl catches (Fig. 3), individuals aged 2-6 years with a total length of 39-76 mm with a body weight of 0.25-2.91 g were recorded, but fish up to 50 mm in length with a body weight of less than 0.5 g predominated. The proportion of females increased sharply among individuals with a length of more than 68 mm, reaching 100% with a length of over 75 mm. Males and females of the species in question begin to mature in the third year of life at a length of 47-48 mm and 52-58 mm, respectively. Sexual maturity of half of the males and females occurs in the fourth year of life when they reach a length of 52-58 mm and 61-63 mm, respectively. The Arctic alligatorfish is a mesobenthophage, the main food of which is amphipods, which make up about 95% of the diet, but as A. olrikii individuals grow, the number and size of amphipods they consume increases. Along with other small representatives of the benthic high-latitude ichthyofauna, the Arctic alligatorfish can be considered as an indicator species of the state of Arctic ecosystems. Therefore, obtaining new data on the ecology of such species will not only contribute to a better understanding of the functioning of marine coastal ecosystems at high latitudes, but will also make it possible to monitor their condition in the modern period, characterized by sudden climate changes and increased anthropogenic pressure (shipping, mining, fishing, tourism and etc.). Article imprint: Tokranov A.M., Emelin P.O., Orlov A.M. 2024. Armored fish in cold polar waters: new information on the Arctic alligatorfish Aspidophoroides olrikii (Agonidae, Perciformes, Teleostei) from the Kara Sea (Siberian Arctic) // Polar Biology. https://doi.org/10.1007/s00300-024-03280-7

The 5th school-conference "Systematics and faunistics of cladocera crustaceans (Cladocera)" was held from July 1 to July 10 at the Hydrobiological Station "Glubokoye lake" by IEE RAS in the Ruzsky district of the Moscow region 12 students and staff from various cities and institutions of Russia (Irkutsk, Krasnoyarsk, Yekaterinburg, Nizhny Novgorod, Vologda, Yaroslavl region, St. Petersburg and Moscow) took part in the school-conference as listeners in lectures and practical classes. They were given lectures on issues of morphology, taxonomy, biogeography, reproduction and development of cladocerans by employees of the Institute of Ecology and Evolution of the Russian Academy of Sciences N.M. Korovchinsky, O.S. Boykova, A.A. Kotov, A.N. Neretina, A.A. Zharov, P.G. Gharibyan. Associate Professor of the Faculty of Biology of Moscow State University A.Yu. Sinev, currently located at the White Sea Biological Station of Moscow State University, also joined the company of lecturers online. During the school, practical classes were conducted on identifying cladocera crustaceans, both living in Glubokoye Lake and from samples that the participants brought with them. On the last day, a Conference was held, at which students made reports on the materials of their research in the organizations in which they directly work. Some reports aroused keen interest and heated discussion. At the end of the school-conference, students received certificates of participation in it. Fig.2. Practical exercises on identifying cladoceran crustaceans. By now, holding such conference schools on Glubokoye Lake has become a tradition. Unfortunately, the Biological Station is relatively small and cannot accommodate a large number of students, but it can now be considered as a key facility for improving the level of qualifications of hydrobiologists in the study of certain groups of invertebrate animals (in previous years it hosted schools on Copepoda, Ostracoda and freshwater meiobenthic animals generally). Such schools will undoubtedly continue; in particular, a school on paleolimnology is planned for September this year. Fig. 3. Listener conference on the last day of the event. Fig.4. Testing light traps for collecting microscopic crustaceans with positive phototaxis.

Fig.1. Landscapes of the Kalarsky district (photo by E.D. Varakina) From June 12 to June 27, 2024, a junior researcher at the Laboratory of Ecology of Aquatic Communities and Invasions, Elizaveta Dmitrievna Varakina, took a trip to the Kalarsky district of the Trans-Baikal Territory as part of work under the Russian Science Foundation project No. 22-14-00258 and a cooperation agreement between the A. .N. Severtsov Institute of Ecology and Evolution RAS and the Sokhondinsky State Natural Biosphere Reserve. During the business trip, Elizaveta Dmitrievna collected samples of microscopic crustaceans (Cladocera and Copepoda) from different types of reservoirs in the Chara and Middle Sakukan river basins. Particular attention was paid to sampling microscopic crustaceans from Lake Bolshoye Leprindo and forest reservoirs located in its vicinity. Bolshoye Leprindo is the largest lake in the group of reservoirs of the Udokan-Chara watershed, characterized by high transparency and low mineralization. The ice from this lake melts only at the end of May - beginning of June. The microscopic crustaceans of this lake have never before been the object of special faunal studies. Due to its hydrological features, it is expected that this lake will contain a number of rare and interesting species of cladocerans and copepods, valuable for taxonomy and biogeography. Fig. 2 Lake Bolshoye Leprindo (photo by E.D. Varakina) In total, during the trip E.D. Varakina collected 45 samples containing planktonic and benthic-phytophilic crustaceans. All material has been delivered to Moscow and is in the initial stages of processing. At this stage, 15 species of cladocerans and 4 species of copepods have been identified in the collected material. The first interesting find was Ilyocryptus spinifer Herrick, 1882 (Cladocera), traditionally classified as a thermophilic species with a circumtropical distribution. In addition, Elizaveta Dmitrievna got to know the work of the Kodar National Park from the inside and tried her hand at environmental volunteering, taking part in a project to clean the shores of Lake Bolshoye Leprindo from garbage. Work by E.D. Varakina in the Kodar National Park became possible thanks to the comprehensive assistance and support of its employees. The Laboratory of Ecology of Aquatic Communities and Invasions expresses sincere gratitude to all employees of the national park for their assistance in organizing research. As part of the concluded cooperation agreement, the Kodar National Park invites all interested scientists from the Institute of Ecology and Evolution of the Russian Academy of Sciences involved in research into the biota of aquatic and terrestrial ecosystems to cooperate, and is waiting for them in the next field season.