Биологическое разнообразие бухты Круглой и перспективы создания орнитологического заказника (юго-западный Крым, Чёрное море)

Актуальность изучения гидрофильных птиц в городских зонах черноморского побережья обусловлена их важной ролью в структуре прибрежных биоценозов и необходимостью сохранения биоразнообразия в условиях антропогенной трансформации береговой зоны Крыма. Исследована динамика видового состава и численности птиц бухты Круглая (Севастополь). Материал собран в 1995 и 2005–2016 гг. В бухте Круглая установлено пребывание 51 вида водных и околоводных птиц из 8 отрядов. Зимний орнитокомплекс наиболее разнообразен и многочислен (32 вида: 14 Anseriformes, 7 Charadriiformes, 5 Podicipediformes, 3 Gruiformes, 2 Pelecaniformes, 1 Gaviiformes). Регулярно зимуют и количественно доминируют 8 видов – Cygnus olor, Anas platyrhynchos, Aythya ferina, Aythya fuligula, Fulica atra, Larus ridibundus, Larus cachinnans и Larus canus. Определены численность всех видов птиц, возрастной состав Cygnus olor и половой состав Anas platyrhynchos, Aythya ferina и Aythya fuligula. Основу орнитокомплекса составляли бентофаги (не менее 13 видов), ихтиофаги (5) и эврифаги (4). Отмечено 30 пролётных и кочующих видов, преимущественно Charadriiformes (11), Anseriformes (7) и Ciconiiformes (5). Гнездовой орнитокомплекс отсутствовал, только в 2016 г. зарегистрировано гнездование Ixobrychus minutus. Весенний пролёт проходил с конца февраля до мая, осенний –– с августа до первой декады ноября. Для сохранения данной бухты как ценного природного и эколого-воспитательного объекта целесообразно придание ей статуса природного парка.

Актуальность исследования загрязнения бухты Круглая обусловлена неблагоприятной обстановкой в её акватории в сезоны с усиленным антропогенным прессом и условиями среды, благоприятными для активизации процессов роста биологических объектов. Особенно это касается загрязнения органическими веществами, как от аварийных источников, так и при естественных процессах жизнедеятельности населяющих биотопы организмов. Конечным пунктом миграции и осаждения этих веществ являются донные осадки, анализ которых даёт возможность представить устойчивую картину загрязнения. Поэтому целью работы стала оценка многолетних изменений состояния донных осадков в бухте Круглая. Материалом для исследования послужили пробы донных осадков, отобранные в бухте Круглая дночерпателем Петерсена. В подготовленных соответствующим образом воздушно-сухих пробах находили общее количество хлороформ-экстрагируемых веществ ― весовым методом, нефтяных углеводородов ― методом инфракрасной спектрометрии. В результате анализа многолетней динамики загрязнения органическими веществами донных осадков бухты Круглая (Севастополь, Чёрное море) в период 2006–2015 гг. выявлены его неравномерное распределение по акватории бухты и явная приуроченность к источникам загрязнения. Наиболее чистой является центральная часть акватории, а наиболее загрязнённой ― вершина бухты, где на отдельных точках степень загрязнения достигает IV уровня. Об интенсивном накоплении загрязняющих веществ на станции 01 свидетельствую высокие концентрации хлороформ-экстрагируемых веществ (на самой станции ― 900, в прибрежных наносах вблизи станции ― 620 мг·100 г−1 воздушно-сухого донного осадка). Таким образом, отмечено общее снижение концентрации хлороформ-экстрагируемых веществ за весь период исследований, за исключением станции 02, но доля нефтяных углеводородов выше по всей акватории вершины б. Круглой.

The bays of the northern coast of the Heraclean Peninsula including the Kruglaya Bay are characterized by the abundance and diversity of the winter hydrophilic ornithocomplex, which is one of the largest in Crimea. To date, the bird list of the Kruglaya Bay includes 75 species. Its coast and water areas are suitable for the wintering of hydrophilic birds, of which 8 species winter annually and 20 - periodically. The total number of birds was 0.99-1.38 thousand individuals during the main wintering period (December-January) in different years, with a significant dominance (55-72%) of the coot and black-headed gull. The protected species include 13 bird species listed in the Red Data Books (RDB) of various ranks, of which 10 species are represented in the RDB of the Russian Federation, 4 in the RDB of Sevastopol and 4 in the IUCN List of Threatened Species. In addition to the diverse and numerous hydrophilic ornithocomplex, a significant species richness of aquatic organisms and a variety of benthic biotopes were observed in the Bay. The ichthyofauna is represented by 60 species (2 of them are protected), the macrophyte flora includes 41 species (4 protected), the macrozoobenthos - 124 species (7 protected), and 43 species of the epiphyton are registered. 90 vascular plant species have been identified in the coastal zone, of which 12 species are protected. Large regular and seasonal accumulations of hydrophilic birds, a high degree of biota diversity, the presence of many protected species and diverse biotopes testify to the nature conservation value of the Bay. They are the basis to establish an ornithological reserve in its water area with a protection regime in winter, as one of the largest avifauna reserves in Southern Crimea.

Recent studies on climate change have reported serious impacts on winter forest birds in Western Europe. However, in areas where climate change has caused milder winters and more stable conditions in summer, one would expect resident bird populations to increase, rather than to decrease in winter. The aim of this study was to investigate the impact of climate change on the population dynamics of ten species of Passeriformes in the Tartarstan Republic, Russia. Ravkin's transect method was used to census fixed randomly selected plots spread over a large geographic area at least once every month for the past 26 years. Observers remained the same over the whole period. The abundance of nine species in the first half of the winter and four species in the second half of the winter showed significant increases during the study period. Unlike studies from countries in Western Europe, there were no significant decreases in these species. Significant changes in winter conditions, as well as during the breeding season, and an overall increase in annual temperatures are likely reasons for a significant increase in the number of birds in winter. Greater winter survival, an increase in the survival rate of fledglings and juveniles during the summer, and later onset of winter, are very important determinants of the winter population. Our findings show that numbers of birds in late winter are related to the severity of winter conditions. Our data do not support conclusions that the populations of forest bird species have decreased due to climate change.

Sea level oscillations spectra of a shallow coastal bay: Cost-effective measurements and numerical modelling in Kruglaya Bay

Актуальность изучения экологических и поведенческих адаптаций гидрофильных птиц в городских зонах Крыма обусловлена необходимостью сохранения биоразнообразия в условиях антропогенного преобразования внутренних водоёмов и морских берегов полуострова. Целью исследования было выявление условий, определяющих эффективность размножения волчков в биотопе с высокой антропогенной нагрузкой; задачами исследования — определение пищевого спектра, поведенческих реакций и сроков пребывания птиц в биотопе. Впервые в городской зоне черноморского побережья Крыма (бухта Круглая, Севастополь) зарегистрировано гнездование малой выпи (волчка) Ixobrychus minutus (Linnaeus, 1766). Визуальное наблюдение, фото- и видеосъёмку проводили не менее пяти раз в неделю. Пару взрослых особей наблюдали с 3 июля до 2 августа, трёх молодых особей — с 24 июля до 7 сентября 2016 г. в вершине бухты. Успешному размножению волчков способствовали наличие естественных укрытий (зарослей тростника) и хорошая кормовая база. Основной добычей птиц была молодь кефалей, также отмечены случаи поимки глазчатой зеленушки, морской собачки-павлина и различных беспозвоночных. Птицы проявляли нетипичное для своего вида синантропное поведение. Результаты исследования свидетельствуют о достаточно высоком адаптивном потенциале волчка к различным факторам беспокойства в городской зоне черноморского побережья Крыма. Предполагается возможность «возвратной урбанизации» волчка — заселения им исходных местообитаний (зарослей околоводной растительности в вершинах некоторых бухт городской зоны Крыма).

New data on the distribution of the bar-tailed godwit Limosa lapponica (Linnaeus, 1758) and red-throated diver Gavia stellata (Pontoppidan, 1763) on the Crimean Peninsula are presented. Against the backdrop of aquatic and coastal ecosystems’ transformation under natural and anthropogenic impact, even single finds of hydrophilic avifauna representatives in atypical spatiotemporal conditions are of interest for the analysis of emerging trends in migration phenology and abundance of both separate species and taxonomic and ecological groups of birds. The aim of the study was to clarify the distribution boundaries and terms of stay on the Crimean Peninsula of two hydrophilic bird species: semiaquatic species, bar-tailed godwit, and true water bird, red-throated diver. Bird observations were carried out during scheduled accountings on the Isthmus of Ak-Monay (March 2012) and in the Kruglaya Bay (Sevastopol) (July 2019). The bar-tailed godwit is registered in Crimea during spring and autumn migration periods. For the first time, it was found in the north of the Crimean Peninsula in 1972; later, there were an increase in its abundance and expansion of a distribution area. Recent records of this species in southern Crimea significantly expanded the known boundaries of its distribution on the peninsula during the migration period. The observation of the bar-tailed godwit in eastern Crimea on 14 March, 2012, specified the date its spring migration begins; the observation in Sevastopol (western foothill) on 27 July, 2019, was the first one in Mountain Crimea. Off the Crimean coast, the red-throated diver is a rare overwintering and migratory bird. The find of the red-throated diver individual in the Kruglaya Bay on 19 January, 2020, was the third reliable record of this species overwintering in Crimea and the first one in Sevastopol area. The registration of the red-throated diver at a considerable distance from its usual overwintering areas (off the southwestern coast of the Black Sea), along with numerous facts of the expansion of nesting or winter ranges of different bird species northward, confirms the ongoing climatic and ecological changes. Particular attention should be focused on the problem, associated with low ecological culture of the use and disposal of fishing tackles, which have a detrimental effect on hydrophilic birds. Measures have to be developed to regulate fishing with nets, hooks, and line tackles in the areas of bird mass overwintering and seasonal migrations.

Contents of an Early Byzantine Amphora from Kruglaya Bay, the Black Sea

The article provides summarized data of species composition, abundance, biomass, occurrence and trophic structure of invertebrate macrozoobenthos associated with red-book algae Сystoseira crinitа Duby, 1830 in the coastal waters of the Crimea (Cape Tarkhankut, Kruglaia Bay, Simeiz, «Cape Martyan» Reserve, Dvuyakornaya Bay) and the Caucasus (in the area of «Utrish Nature Reserve») in August-September 2012–2017 at the depth of 1, 3 and 5 m. A total of 46 samples were taken (42 quantitative and 4 qualitative). In the area of Utrish, such studies were carried out for the first time. In the algae communities of the Black Sea coast of Crimea and the Caucasus 56 species belonging to the types Annelida, Platyhelminthes, Mollusca and Arthropoda were identified. Ten species are common to all areas. The abundance and biomass near the Caucasus coast were 1432 ind. kg-1 and 9,52 g∙kg-1, near the coast of Crimea these values varied from 2506 to 6085 ind. kg-1 and from 23,9 to 43 g∙kg-1 respectively. Mollusks and crustaceans dominated in values of abundance, mollusks dominated in values of biomass. The highest quantitative indicators were recorded in the waters of Simeiz, the lowest – in the area of the «Utrish» Nature Reserve. Molluscs, in particular, Mytilaster lineatus Gmelin, 1791, make a significant contribution to the formation of macrozoobenthos abundance in the Simeiz area, while in the water area of Utrish the peaks of abundance have been defined due to crustaceans Ericthonius difformis M.-Edwards, 1830 and Ampithoe ramondi Audouin, 1826. Gastropods Rissoa splendida Eichwald, 1830, Bittium reticulatum (da Costa, 1778) and bivalve M. lineatus make the greatest contribution to the biomass of macrozoobenthos both in the waters of Simeiz and in the Utrish Reserve area. The high abundance and biomass of these molluscs allow them to form a macrozoobenthos nucleus in the studied water areas. Comparison of species composition of macrozoobenthos by the Chekanovsky-Sörensen community index showed high fauna similarity in all areas (the coefficient ranged from 0,4 to 0,76), as they are bound by the same biotope. The fauna of the Kruglaya Bay and Cape Tarkhankut are the most similar to each other. The areas in Dvuyakornaya Bay and Cape Martyan are the least similar to each other. The results of the cluster analysis confirm that the most similar areas in terms of presence/absence of species are Kruglaya Bay and Cape Tarkhankut, and also Dvuyakornaya Bay and Utrish area. The functional abundance index determined the communities of gastropod molluscs R. splendida (in the Tarkhankut, Simeiz and Utrish areas), B. reticulatum (in Kruglaya Bay) and bivalve M. lineatus (in Cape Martian and Dvuyakornaya Bay). It has been shown that the R. splendidа communities are more attracted to open coasts. In the R. splendida community from 16 to 25 species have been recorded in different areas, in the M. lineatus community in the water areas of the Cape Martian and Dvuyakornaya Bay (only quantitative samples were taken into calculation) 16 and 17 species were identified, in the B. reticulatum community – 25. In the majority of communities the guiding species were predominated. Their proportion was between from 32 to 56 % of the total number of species. Characteristic species dominate only near Utrish. Their share is 36 %. The number of rare species in communities varies from 3 to 9. The dominance-diversity curves indicate a more stable state of the epiphyton community in the water areas adjacent to the Utrish Reserve and Kruglaya Bay. Shannon index values also indicate high biodiversity in the studied water areas. The maximum Shannon Index value in terms of abundance was recorded in the B. reticulatum community (2,66) in Kruglaia Bay and a high value in terms of biomass (2,34) was marked in the R. splendida community in the Simeiz area. Five trophic groups have been identified. Phyto- and polyphages dominate by the number of species. Phyto- and sestonophages dominate in values of abundance, phytophages – in values of biomass.

Fungi in marine environments, including yeasts, are far less studied than fungi in terrestrial environments, not only in Black Sea but also all over the world. The data about the biochemical activity of marine yeasts are presented. Yeast strains were able to be isolated from bottom sediments of three Sevastopol bays (Karantinnaya bay, Kruglaya Bay, and Yuzhnaya bay) during a sanitary-ecological survey of department of marine sanitary hydrobiology IBSS. We have showed hydrochemical characteristic of the studied area based on the literature review. The isolates grew well in a medium composed of sugars (glucose, lactose), in vitro ability to degrade starch and peptone. In addition, they used oil and petroleum hydrocarbons as the only source of carbon and energy actively. The indigenous microflora in heavily polluted environments faces a regular threat from pollutants and has therefore evolved the necessary enzymatic setup for their detoxification.

For the first time in the Kruglaya Bay of the Black Sea, 25 taxa of Bacillariophyta from 17 genera were found, three of them were new for the Crimea and the Black Sea Halamphora tenerrima, Amphora tenuissima, and Navicula antonii. Marine (40%), coastalbrackish (32%) and boreal-tropical (32%), arctic-boreal-tropical (24%), boreal and cosmopolitan (20% and 16%, respectively) prevailed. The morphological characteristics of the species in the SEM (scanning electronic microscope) and LM (light microscope), as well as the occurrence, ecology, phytogeography, and general distribution in various regions of the World Ocean are given.

Aim. Study of a group of biochemical parameters of the hepatopancreas and gills of the Black Sea mussel Mytilus galloprovincialis Lam. and the functional indicator of cardiac system adaptivity of mussels from Sevastopol bays with different levels of recreational and anthropogenic impact.Methods. Mussels were collected from four Sevastopol water areas (Kruglaya Bay, Kazachya Bay, Matyushenko Bay and Cape Khrustalnii) in autumn 2018. The bioindication methods used were based on application of functional (cardiac system adaptability) and biochemical indicators (antioxidant enzymes activity [AEA], aminotransferases, the alkaline phosphatase [AP], and products of the lipid peroxidation [LPO] and protein oxidation [PO]) of mussel tissues. The hydrochemical parameters of the investigated areas were determined.Results. The anthropogenic impact on a complex of biochemical indicators of mussels at the sampling sites was shown. At the same time, low values of mussel heart rate (HR) recovery time (Trec) (less than 60 min.) in all sampling sites demonstrated the efficiency of biochemical changes in mussels and the possible use of all tested bays as recreational areas.Conclusion. Results of the present research allow the characterization of the ecological status of these Sevastopol sea water areas and to make recommendations about their rational use. Matyushenko and Kazachya Bays are most suitable for beach recreation and recreational fishery. Kazachya Bay also has favourable conditions for the development of water sports. Kruglaya Bay and Cape Khrustalnii are less ecologically safe and require a series of actions to improve water quality.

Two species of sessile ciliates from subclass Peritrichia, Vorticella pyriforme and Zoothamnium sinense, new for Black Sea, were found in the Kruglaya Bay (the Black Sea) on algae Cystoseira crinita and Cladophora sericea. The article provides a description, systematic position and data on the distribution of the collected species.

Хищный брюхоногий моллюск-вселенец Rapana venosa (Valenciennes, 1846) в настоящее время является важным звеном экосистемы бентали Чёрного моря. Систематический мониторинг его популяций –– неотъемлемый элемент мониторинга Чёрного моря. В летний период 2015 г. проведено исследование популяций R. venosa в четырёх бухтах Севастополя: Голубой, Казачьей, Круглой, Стрелецкой. Определены и сопоставлены основные популяционные характеристики R. venosa. Проанализирован размерный, массовый, возрастной и половой состав популяций рапаны исследованных бухт. На основе полученных сведений дана оценка современного состояния и перспектив развития локальных популяций рапаны этих бухт. Наиболее сбалансирована по структурным показателям локальная популяция рапаны бухты Круглая, которая находится в относительно устойчивом состоянии. Локальные популяции R. venosa в остальных бухтах в разной степени квазиустойчивы. Предполагается, что основным фактором, определяющим структурные особенности популяций рапаны бухт Севастополя, является кормовая база.

Ichthyofauna monitoring of the Crimean coastal water area is one of the most important parts in the research of the current condition of the Black Sea ecosystem. In last 10 years of XX century anthropogenic impact caused significant critical changes, resulted in essential degradation of phyto- and zoocenoses. Similar situation was observed in fish populations. The article presents a schematic chart with the detailed bottom relief description, features of underwater landscape of the Kruglaya Bay and adjacent open water areas. The paper deals with spatial distribution and seasonal dynamics of three ecological groups of fish: pelagic, benthopelagic and benthic, that inhabits pelagic, solid and soft grounds. 57 species that belong to 36 families were found during the research period. In the ichthiocen of solid ground the benthopelagic fishes prevailed, presented by 14 species of 7 families (Labridae, Syngnathidae and Sparidae). Benthic fishes were presented by 8 species from 5 families. Among 20 species from the soft ground area 6 were benthopelagic species and 14 – benthic species. The most diversity was observed in Gobiidae family. It should be noted appearance of Sarpa salpa (L., 1758) in June 2005 in the bay water area. The results may give an assessment of current condition of sea fish populations of sea coast of Crimea and may be useful at comparison with other parts of water areas of the Black Sea.