卷 104, 编号 7 (2025)

The morphological variability of metacercariae of the digenean, Diplostomum numericum from the vitreous eye body of the roach was studied from three water bodies in Karelia, northwestern European Russia: Lake Kamennoye (a protected natural lake), Lake Kostomukshskoye and Lake Okunyovoye (both latter contaminated by mineral wastes). Qualitative variations were revealed in the major morphological traits (shape of the body, suckers, pharynx, and holdfast organ). A high phenotypic diversity of D. numericum populations was observed, these being expressed in numerous variations in traits and a wide range of their combinations. The intra-­population variation range of these traits was much wider than inter-­population differences. The population-­level structure of the variability in D. numericum was similar in the protected lake and in the contaminated ones. The dominant trait variations were consistent across the D. numericum populations: oval and elongate body shape, rounded and oval oral sucker shape, rounded pharynx shape, broad and rounded ventral sucker shape, broad holdfast organ. However, samples from contaminated water bodies showed novel, rare variations, as well as an altered and more uniform distribution of their variation frequencies. The plasticity of the traits and the dynamic phenotypic diversity in lakes with different levels of contamination indicate the wide adaptive capacity of D. numericum intraspecific diversity, this ensuring the resilience of this species under anthropogenic pollution.

The roles the passerine birds play in the feeding of tick larvae and nymphs in the Gomselga Field Station area located in the middle taiga subzone of southern Karelia (N62.07°, E33.96°) were studied. A total of 235 birds belonging to 29 species of 12 families were examined, from which 19 larvae and 69 nymphs of Ixodes persulcatus (Schulze, 1930) were collected. Ticks were detected on 14 bird species (Anthus trivalis, Emberizia citrinella, Erithacus rubecula, Fringilla coelebs, Parus major, Phoenicurus phoenicurus, Pica pica, Prunella modularis, Pyrrhula pyrrhula, Troglodytes troglodytes, Turdus iliacus, T. merula, T. philomelos and T. pilaris), with the highest infestation rates found for P. modularis and T. iliacus. We used the division of birds into ecological groups proposed by R. L. Naumov (1961). The highest prevalence of I. persulcatus, both larvae (8.5%) and nymphs (21.7%), was typical of the birds of the first ecological group, those that collect food from the ground. The estimates of the total numbers of parasitic I. persulcatus larvae and nymphs during the season suggest that birds are important hosts in the life cycle of ticks in the study region.

We examined data on white-­fronted geese breeding performance in 1998–2007, 2012 and 2014–2020, and on bean geese in 2003, 2006 and 2016 in the vicinities of the Medusa Bay (73°21ʹ N, 80°32ʹ E), northwestern area of Taimyr Peninsula. In 2015–2017, 2021 and 2023 we collected data at the “Pura” stationary (72°17ʹ N, 85°45ʹ E), central Taimyr Peninsula, as well. White-fronted goose distribution pattern was analyzed for a number of habitats: 1) the flat mainland tundra; 2) the rocky banks of the large tundra rivers and rocky cliffs of the seashore; 3) the flat tundra on a river island. White-fronted goose breeding possibility positively related to the lemming number score. In years with high arctic fox activity, these geese nest preferably on the steep rocky riverbanks, practically every time under the protection of the patron predators: peregrine falcons and snow owls. In the flat tundra of the northwestern Taimyr Peninsula, white-­fronted geese breed sparser than in the tundra of the central Taimyr, as well as on rocky riverbanks and river islands. In their choice of nest sites within the homogenous tundra these geese, although not in great extent, focus at the relatively permanent subareas of the tundra where geese breeding took place in previous years. One of the unclear questions related to the white-­fronted goose population social structure is the existence of so-called “accompanying pairs” near some nests. These pairs do not breed and breeding pair allow them to stay very close to their nest. Suggestively, these accompanying pairs are originated from the previous year offspring of the breeding pair. Parts of the tundra where white-­fronted goose nests appeared from year to year do not apparently differ from the areas without every year nests. Nevertheless, geese settle in the same restricted areas through years, in spite of seemingly the same kind of tundra nearby. Being aware about the type of geese nest distribution in different parts of tundra, one can calculate the probability to find another nest of the same species in the sequential seasons within the limits of the some given distance from the found nest. Bean geese appeared to be a species that is more attached to river streams than white-­fronts. Nests of these geese were never found far away from rivers or creeks.

In 2023–2024, new habitats of the Giant Noctule, Nyctalus lasiopterus, were located in the North-­West of the Caucasus (Anapa District, Krasnodar Region: N44°45ʹ16.5ʺ, E037°27ʹ26.5ʺ; N44°48ʹ19.8ʺ, E037°26ʹ02.5ʺ; N44°48ʹ11ʺ, E037°25ʹ48ʺ). A total of 50 individuals (7 adult females, 25 females and 18 males young) were captured. The newly identified local group of N. lasiopterus (47 individuals) is the largest known yet in Russia. All animals are caught in areas of broad-­leaved old-growth forests near water bodies. The Giant Noctule belongs to the group of long-distance migrants, which over most of their distribution range carry out seasonal flights (more than 300–400 km) from areas of summer habitats and breeding to and from wintering grounds. In terms of age and sex, among the N. lasiopteru captured, there were only adult females with signs of post-lactation and young, while adult males were absent, this being characteristic of a breeding area. In the Anapa District of the Krasnodar Region, in the territory of the Utrish Nature Reserve and its environs, the Giant Noctule is a common species. In terms of relative abundance (7.5%), among the 667 bats of 16 species captured, N. lasiopterus is subordinate only to Leisler’s Bat, N. leisleri (48.1%) and the Serotine, E. serotinus (7.8%). New records confirm that the northwestern Caucasus is a breeding area for N. lasiopterus, as well as a transit territory for migratory individuals. These records are the basis for future monitoring studies. To preserve the population of N. lasiopterus, it is necessary to study the regional ecology of the species, the distribution and protection of deciduous forests as key habitats, as well as to manufacture and hang artificial shelters for bats at forest edges and near water bodies.

Special studies were carried out in the territory of the Priladozhsky Theriological Research Centre (Karkku village, Pitkyaranta District, Karelia) in 1986–1997, supplemented by periodic visits between 1998–2015. By using tagging and live trapping we traced territorial relationships of 193 field voles. The number of recaptured voles amounted to 833. Adult animals of this species were found to often form microcolonies during their life, living in small family groups. Each group included 2–3 broods obtained from one pair of animals and settled in closely located habitats 10–20 m² in area. At the northern periphery of the distribution range, characteristic differences in spatial groupings of certain age and sex groups were established. Adult (overwintering) females adhered mainly to certain individual territories with an average area of 880 m², with fluctuations from 300 to 2200 m². Males were considerably more mobile compared to females and occupied areas that overlapped with other males’ territories. The territorial behavior of juvenile individuals of was heterogeneous and depended on their participation in reproduction. Breeding young individuals occupied relatively smaller areas. Non-breeding individuals were mush more mobile and did not adhere to any certain territory.