silhouette of a gray heron (ardea cinerea) on the banks of the rhine at dusk

serene glow peaceful biology gloaming sundown twilight art sunset dark animal dawn bird ecology walking aquatic sunlight themes water zoology environment nature scenery fishing wading ornithology tranquil scene swamp heron wetland beauty silhouette gray ardea cinerea banks rhine dusk dusk sasbach kaiserstuhl emmendingen fribourg-en-brisgau bade-wurtemberg allemagne