The study is part of hydromycological investigations of man-affected water bodies in Olsztyn. Our results show that yeast-like fungi are permanent components in three selected lakes (lakes Tursko, Długie and Skanda). Their abundance and species composition depend on the trophic state of each lake.

Yeasts are a distinctive group of microfungi, but compared to other microorganisms, their ecological function and biodiversity are poorly known. This is especially so where polar ecosystems are concerned. With climate changes and increasing pollution levels in the Arctic, it can be anticipated that there will be an increase in the prevalence and diversity of fungi colonizing live organisms. With these changes, it is crucial to investigate and monitor species diversity and prevalence of fungi in this fragile environment. In this study, yeasts were examined from throat and cloaca of a small colonial seabird, the little auk (Alle alle), a keystone species in the Arctic ecosystem. Samples were collected from 94 adults and 17 nestlings in breeding colony in Magdalenefjorden (NW Spitsbergen) in 2009. In total, twelve species of yeast from eight genera were found in 12 % of the samples, with the Dipodascus genus being the most prevalent. All yeast species were found in the adults, but only one species, Cryptococcus macerans, was found in a single nestling. In individuals where fungus was isolated, it was only isolated from either the throat or the cloaca, except for two cases, where fungus was found in both throat and cloaca. The presence of yeast was not related to sex but age of the birds, with adults being more prone to colonization by yeasts than the nestlings. The relatively low prevalence and diversity of yeast in little auks suggest that these birds are random carriers of fungi, with minor health impacts.

The paper presents mycological studies conducted jointly with ornithologists on the epidemiology of mycoses and the taxonomic diversity and prevalence of fungi that colonise the selected onthocenoses in healthy, wild migratory birds. Aquatic ecosystem populations of healthy birds include a percentage of carriers of potential zoo-and anthropopathogens, and this study's purpose was to determine the percentage. The studies were performed on swabs sampled in vivo (during spring and autumn migrations) from the beak and cloaca of nine species of Charadriiformes in two age categories. Macro-and microcultures of fungi were prepared according to the standards for diagnostic mycological laboratories. From the 450 birds examined, fungi were isolated from 130 (26.5%) individuals. The sampling yielded 272 yeast isolates: 170 (62.5%) from the beak and 102 (37.5%) from the cloaca. The isolates represented 23 species, among which C. albicans, C. neoformans, and R. rubra were predominant. In both onthocenoses in young and adult birds, more fungi were recorded in autumn than in spring. As many as 15 species are included in the biosafety level classification, of which seven are categorised as category 2 and one as category 3.

The aim of the study was to determine the species composition of fungi occurring on wall surfaces and in the air in school buildings. Fungi isolated from the air using the sedimentation method and from the walls using the surface swab technique constituted the study material. Types of finish materials on wall surfaces were identified and used in the analysis. Samples were collected in selected areas in two schools: classrooms, corridors, men's toilets and women's toilets, cloakrooms, sports changing rooms and shower. Examinations were conducted in May 2005 after the heating season was over. Fungi were incubated on Czapek-Dox medium at three parallel temperatures: 25, 37 and 40°C, for at least three weeks. A total of 379 isolates of fungi belonging to 32 genera of moulds, yeasts and yeast-like fungi were obtained from 321 samples in the school environment. The following genera were isolated most frequently: <em>Aspergillus, Penicillium</em> and <em>Cladosporium</em>. Of the 72 determined species, <em>Cladosporium herbarum, Aspergillus fumigatus</em> and <em>Penicillium chrysogenum</em> occurred most frequently in the school buildings. Wall surfaces were characterised by an increased prevalence of mycobiota in comparison with the air in the buildings, with a slightly greater species diversity. A certain species specificity for rough and smooth wall surfaces was demonstrated. Fungi of the genera <em>Cladosporium</em> and <em>Emericella</em> with large spores adhered better to smooth surfaces while those of the genus <em>Aspergillus</em> with smaller conidia adhered better to rough surfaces. The application of three incubation temperatures helped provide a fuller picture of the mycobiota in the school environment.

Fungi of the genus Trichosporon are widespread in the biosphere and are a frequent component of the skin mycobiota. They are opportunistic organisms that adopt a commensal lifestyle on the skin in healthy humans but can cause pathological changes (trichosporonosis) of various intensity and range in immunocompromised persons. The species recorded in our study (T. asahii, T. capitatum, T. cutaneum, T. inkin, T. pullulans) are potential anthropopathogens. T. asahii, T. cutaneum and T. inkin are classed as BSL-2 in the biosafety classification.