卷 7, 编号 2 (2016)

The questions of woody invasive plant introductions into natural communities of the Upper Volga region are considered. It is established that, of 798 alien species of the region, 119 (14.9%) are woody plants, 27 tree and shrub species successfully naturalized and intruded into natural communities of various degrees of disturbance, and 7 species are included in the Black Book of Central Part of European Russia. The majority of invasive woody plants are species of Northern American origin. Examples of invasive woody species introduced into plant communities of the region, including the specially protected natural territories, are given.

Bidens frondosa L. populations are studied in the Republic of Mordovia. The density of individuals of invasive species is high and it fluctuates on average from 78 to 202 individuals per 1 m². A comparison of the seed mass, the number of seeds per calathidium, the seed germination, and the area of torus of calathidium of alien B. frondosa with those for native B. tripartita L. is carried out. Seed germination of B. tripartita (on average from 32.3 to 41.7% depending on conditions of germination) is considerably higher than that for B. frondosa (from 1.7 to 8.0% depending on conditions of germination and the sites of seeds harvesting). The number of seeds per calathidium and seed mass are higher in population of native species. Invasive activity of B. frondosa is explained by a more rapid development during ontogeny, but it is not explained by features of the reproductive biology of this alien species.

The literature sources and collection materials providing evidence of the repeated penetration of the land mollusk Cryptomphalus aspersa into the territory of Eastern Europe are analyzed. In the second half of the 19th century and the beginning of the 20th century, mollusks of this species were found in the Crimea (Feodosia), Northern Black Sea coastal region (Odessa, Kherson), and even in the forest-steppe zone of Ukraine (in the vicinity of Vinnitsa). The latter finding is verified by a shell from the malacological collection of the State Museum of Natural History, the National Academy of Sciences of Ukraine. Apparently, the intentional or accidental introduction of C. aspersa into the territory of Eastern Europe continued, but there are still no data confirming the formation of stable colonies. The finding of two specimens in the town of Vinogradov (Transcarpathian region of Ukraine) made by one of the authors of this paper in 2014 is an example of unintentional delivery of this species.

To date, 22 alien fish species are known in the Ob River basin. Of them, nine species—Pike-perch Sander lucioperca, Freshwater bream Abramis brama, common carp Cyprinus carpio, belica Leucaspius delineatus, bleak Alburnus alburnus, Stone moroko Pseudorasbora parva, Amur sleeper Perccottus glenii, Nikolsky’s loach Misgurnus nikolskyi, and southern ninespine stickleback Pungitius platygaster—formed self-reproducing populations and started self-spreading in natural waterbodies. This paper summarizes the data on invasion of alien fish species in the Ob River basin. The data on history, rate of spread, modern distribution, and relative abundance are given. It is shown that water temperature is the main environmental factor which limits the expansion of introduced species in the Ob basin.

Two alien polychaete species of genus Marenzelleria Mesnil, 1896 (fam. Spionidae) were recorded in the monitoring studies in the Don River delta and Taganrog Bay. The species of this genus as a rule occur in marine biotopes varying in the extent of desalination and were not recorded previously in the Azov-Black Sea basin. Adult specimens were collected in March–April and November 2014. In addition, high abundances of spionid nectochaetes supposedly belonging to these species were recorded in February 2014 in Taganrog Bay. Descriptions of sampled adult and larval specimens are given; two morphological groups are distinguished, followed by a discussion on their identity and possible consequences of their introduction. Presumably, transfer of pelagic larval stages in ballast water tanks from the Baltic Sea or North Sea was the main vector of their penetration into the study region.

The paper presents data on the findings of Brazilian elodea Egeria densa, an alien species, in two cooling ponds of the Verkhnii Tagil Power Plant (Middle Urals). The most probable reason for the appearance of E. densa in the cooling ponds is invasion from aquarium culture.

Data on the finding of Apophallus müehlingi (Jägerskiöld, 1899) Lühe, 1909 in gulls of Lake Ladoga and its morphological characteristics are provided for the first time. In common gull (Larus canus), this parasite occurred more often. In little gull (L. minutus), trematodes were single specimens. Mature A. müehlingi are registered only in these gull species during the spring period, immediately after their return from the wintering areas. Detection of the parasite indicates a potential environmental threat. To date, A. müehlingi is found only in the definitive host. However, the penetration of gastropods Lithoglyphus naticoides Pfeiffer, 1828, the parasite’s first intermediate host, into Lake Ladoga will form favorable conditions for the life cycle of the parasite. This may lead to the epizooty of fish by A. müehlingi.