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Terrestrial gastropods are keenly sensitive to changes in vegetation structure owing to their dependence on moisture. For this reason, low survivorship and recolonisation are to be expected after a fire. The fire described in this paper probably started as a result of the deliberate spring burning of vegetation that got out of control. Analysis of the data collected immediately after the fire does not reveal significant differences in the numbers of snails between habitats. This suggests that there are no refugia for this population: no vegetation-related refugium was confirmed. After the fire, snail numbers were found to have crashed, but the slight increase during the season could have been an indication of incipient recovery. Because the population of this species was consistently small, no differences in survivorship between habitats, regardless of their type, were discernible. The effects of the fire on this population in the River Nida Inland Delta were devastating: while it did survive the fire, its numbers fell sharply, by as much as two orders of magnitude.

This article reports a large‐scale die‐off of approximately one‐third of the unionid mussels inhabiting a shallow, naturally eutrophic, floodplain lake (Zalew Pinczowski), which took place within the space of just a few days. Mortality was the highest in Pseudanodonta complanata (81%), followed by Unio pictorum (58%), Anodonta cygnea (26%), Unio tumidus (15%), and Anodonta anatina (5%). It was significantly related to mussel size (age) only in A. cygnea, with the mortality rate higher in smaller (young) mussels. Pseudanodonta complanata was already the rarest species in the lake, and the number of survivors decreased to such an extent as to trigger a possible Allee effect. The most likely cause of the die‐off was a motor‐boating incident that had directly preceded the die‐off. Analysis of the water samples collected just after the die‐off revealed an extremely high concentration of phosphate (up to 0.5 mg dm⁻³) and nitrite (up to 0.06 mg dm⁻³). We suggest that the boat movements must have disturbed the lake sediments, thereby disrupting the mussels' physiology and causing mass mortality. The high sensitivity of P. complanata to environmental stress suggests that it may be an effective umbrella species for the protection of co‐occurring mussel species in eutrophic lakes.

The life cycle of unionids is characterized by a obligatory period of larval parasitism on a fish host, any disturbance of which might cause a large-scale decline in the mussel population. Because the probability of fish infestation is so important, we modelled what would happen to a population (in terms of population growth and probability of extinction), if the same number of glochidia were released in one or more separate spawning events, by a hypothetical mussel population living in conditions differing in the probability of fish infestation (a “neutral” scenario, a “good” one and three variants of a “bad” one). The single brood strategy was the best in the “good” scenario. However, when the frequency of unfavourable stochastic events increased (“bad” scenarios), all strategies led to population decline, the single brood strategy being the worst. In “good” and moderately “bad” conditions the double brood strategy performed better than the other multiple brood strategies, but as infestation conditions deteriorated, a greater number of spawning events ensured a slower population decline and longer persistence. Our model can facilitate a better understanding of this problem and set up a framework for further tests in other unionid species and their environmental conditions.

Despite the high taxonomic diversity, wide distribution and important ecosystem functions of snails, their ecology remains obscure, and this can hamper their conservation. Overwintering in the studied population of Vertigo moulinsiana is effective enough to allow the majority of it to survive. The population dynamics of V. moulinsiana is specific, where the summer boom in a suboptimal habitat covering a small area (wet patches of sweet grass) can determine the snail's range over much larger areas. Our results suggest that humidity could have been the major factor governing population increase. The summer boom is caused by juveniles appearing in very large numbers during this period, thus the peak height is mostly influenced by the considerable susceptibility of juveniles and eggs to desiccation. The limiting influence of humidity is evident in the unequal spatial distribution of individuals: the wetter the substrate, the greater the abundance of snails. As a consequence, the boom may be spatially regulated and only occurs in wet habitats, even though the snail actually occupies a much larger area. Our results indicate that this V. moulinsiana population does not follow typical models constructed for vertebrates or other animals with high dispersal abilities, like the Ideal Free Distribution (IFD) model, and requires a specific approach. Its specific spatiotemporal pattern should be taken into account during monitoring surveys and conservation actions.

Freshwater mussels of the order Unionida provide important ecosystem functions and services. Unfortunately, some previously widespread species are now seriously endangered. To restore the historical range of the population of Unio crassus in the Biala River, southern Poland, the species was reintroduced into a series of ‘stepping stones’ joining two remnant populations. During the first phase of the study, the relationships between the abundance of U. crassus, physical habitat, and water quality were studied to assess reintroduction potential. In general, chemical water quality improved upstream from the existing population, favouring the decision for reintroduction, whereas morphological variables worsened. Mussel abundance was correlated negatively with the elevation and slope of channel, organic matter contents, and pH (exceeding 8.0), but positively with silt presence, water conductivity, and concentrations of HCO3−, Ca2 +, and NO3−. During the second phase, adult individuals were introduced into one type of functional habitat—marginal channel sectors with still water and fine sediment. Despite the initial very high rate of reproduction in some parts of the upper reach of the river, the juveniles were ultimately recruited only in the lower part of the restored range, resulting in a very rapid change in recruitment at a channel slope of 1.8‰. Recruitment was positively related to silt content, conductivity, and Ca2 + and HCO3– ions, negatively to channel elevation and slope, and water pH. The host fish species showed no correlation with abiotic habitat features within the studied reach. These results imply that most of the habitat traits related to U. crassus occurrence depended on the river's longitudinal profile, not on the chemical water quality, and that final success of introduction should be evaluated after several years.

A new large population of the Asian clam Corbicula fluminea (O. F. Müller, 1774) was found within a reach (ca 210 km long) of one of the largest European rivers, the Vistula. The largest population and the largest individuals were found at the outlet of a channel collecting heated water from the cooling process at the Połaniec power station and adjacent parts of the river. In the northern part of the study area, bivalves occurred at the channel margins, in groyne fields, and in the shallows of sand banks or sandbars. The clams were less numerous in places where the river was regulated with straightened banks and stone ripraps. Twenty-five other taxa of mollusks were found altogether at the sampling stations where Corbicula was observed, including other non-indigenous mollusk species.

Although eutrophication of freshwaters is a natural process, the human impact often leads to inland waters becoming overloaded with nutrients, impoverishing many valuable and vanishing habitats, such as floodplain lakes. These changes need to be reversed if the occurrence of endangered aquatic species is to be restored. In this paper we analyse the impact of a change in the water regime of a naturally eutrophic floodplain lake, which harbours a large diversity of Unionidae (large freshwater mussels), a globally threatened taxonomic group that provides important ecosystem functions and services. We found that a slight increase in the discharge from this waterbody, following the construction of an additional outflow pipe, positively influenced recruitment in three of the five mussel species inhabiting the lake. We also found that, after the construction of this additional outflow, the niches of juveniles of Anodonta cygnea and Unio spp. changed, revealing differences in their hydrological requirements. Our results suggest that, as in lotic habitats, complex hydraulic parameters are highly significant to unionid mussels in lentic conditions.

This article discusses the influence of phenology-related intraseasonal asynchrony on metapopulation dynamics and stability. As the part played by intraseasonal asynchrony is as yet unclear and poorly described, greater account of it should be taken in both metapopulation research and conservation practice. The subpopulations of the Parnassius mnemosyne metapopulation studied here are strongly isolated because of the phenological shift between them, despite the relatively small physical distances between them. This isolation is the result of a significant temporal shift in the species' flight periods in the main metapopulation centers: in some seasons its flight times in the different subpopulations did not overlap at all. The predicted results of such strong intraseasonal asynchrony are not altogether clear. On the one hand, they reduce the vulnerability of the entire metapopulation to the effects of short-term random disasters. On the other, the ever-greater isolation of subpopulations may cause the metapopulation to become a nonequilibrium one, which will have a serious impact on its long-term survival.

Lymphoedema is a serious problem in patients treated for malignant neoplasm. The removal of regional lymph nodes – lymphadenectomy – is an inherent consequence of the surgical treatment of malignant neoplasm of breasts, genitals, prostate, skin cancer, salivary glands cancer and many others. The basic methods of conservative treatment of this chronic disease include complex methods of physiotherapy. The aim of this study is to present the rules of rehabilitation of patients treated for lymphoedema, which have been adopted by the team of the Department of Rehabilitation in the Holycross Cancer Centre in Kielce. This paper presents complex methods of physiotherapeutic management and discusses their availability and practical application in Polish health care institutions.

Goląb M.J., Lipinska A.M., Cmiel A.M.: The consequences of water release from a dam reservoir for freshwater mussel survival: recommendations for improved management. ekologia (Bratislava), vol. 29, no. 4, p. 454–459, 2010. dam reservoirs may play an important role in threatened freshwater mussel conservation. However, the restoration works on a dam and their consequences can threaten whole mussel populations. This study investigates the consequences of water release in the Czorsztyn reservoir in order to improve management of dam reservoirs. The analysis shows that the reservoir’s water releases caused massive death of freshwater mussels. The main threat for mussel survival was probably flat slopes that disturbed both their ability to perceive slope gradient and the possibility to escape. in order to decrease the losses of freshwater mussel populations, it is necessary to remodel a part of the reservoir bowl’s shore and to create a refugium for the mussels. if terracing across the slopes is necessary, the steps should not be entirely plain, but tilted towards the water.

The experiment on adult Roman snails (Helix pomatia L.) and their offspring showed a positive correlation between the mean egg size and the parent body size. There was no correlation between the parent size and the number of eggs. A trade-off between the egg size and the clutch size was observed. The body size of juveniles at early growth stages was correlated with the parent size; later (offspring aged 2 and 3 months) there was no such correlation, suggesting maternal effect. The results are relevant to estimating the reproductive success and offspring survival rate at early stages.

Large freshwater mussels (Unionoida) are declining throughout the world. The European bitterling Rhodeus amarus (Bloch, 1782) female spawns its eggs inside the unionids’ shells, where fertilisation and further embryonic development take place; thus its reproduction depends fully on the presence of large freshwater mussels. Unio crassus, previously regarded as one of the most numerous unionids in Europe, is now listed in the IUCN Red Data List as being globally endangered. Despite its previous prevalence, it was never reported as a host for the bitterling. A large population of U. crassus was studied in small river at the Świetokrzyskie Mts (Poland), where also electrofishing was conducted. In each bitterling territory located on the study plots, we found individuals of U. crassus, with the bitterling eggs or larvae developing on mussel’s gills. That proves that this species can be also used by the bitterling for reproduction. We suggest that this relationship has not been reported to date due to the mussels’ rarity and ongoing decline. However, it is also possible that the endangered mussel is a novel host for the bitterling, which is expanding its range throughout Europe.