whooper swan (cygnus cygnus) came to the nest

arctic area big bird birding birds boreal breed breeding brood brooder brooding build clocking clucking clutch cygnus ecology education egg eggs forest forests four hatcher hen incubation island lake landscape lapland laying make marsh moss nature nest nesting nestle nidificate nidify nidus ornithology poultry reproduction sitter sitting students swan taiga tour tundra watching water whistling