mute swan, gygnus olor is sitting on her nest in the park in spring.

adult along animal anseriformes aquatic australis avian bank beak beast biology bird breed breeding brood brooding common construction cygnus day during eggs face fauna flora gygnus hatch hatching her holland lake mute nest nesting netherlands olor orange ornithology park period phragmites pond pool reed shore single sitting spring structure sunny swan village water zuidland