The thesis is devoted to amateur ornithologists and their role in citizen science. In it's theoretical part it focuses mainly on citizen science, its features, history and present of ornithology and characterization of amateur ornithologist. The empirical part uses methods of qualitative research, which is based on semi-structured interviews with professional and amateur ornithologists who participate or deal with projects of citizen science. The research problem is formulated as follows: Amateur ornithologists, their role and involvement in civil science and cooperation with professional ornithologists from the perspective of both amateur and professional ornithologists. It uses a thematic analysis to process the interviews on which several topics are based, for example: amateur ornithologist and its concept, relationships between amateur and professional ornithologists and their cooperation, relationship of amateur ornithologists to nature, their self-education, citizen science from the perspective of amateur and professional ornithologists, data and their quality. Research suggests that the difference between amateurs and professionals lies mainly in their relationship to science, which affects other aspects of their relationship to each other and to citizen science.

No description available.

The thesis describes diversity of birds along a complete altitudinal gradient and in forest fragments in lowlands of Papua New Guinea. It focuses separately on the diversity of different feeding guilds, and discusses their links to habitat and food resources. More specifically, it focuses on forest insectivorous birds, their predation pressure on arthropods, feeding specializations and preferences, and some of the ways how insectivores search for food.