Long-tailed duck / Eisente (Clangula hyemalis)

Wikipedia: Long-tailed duck Source: OTHER Long-tailed-duck.jpg
Classification: Genus Clangula (Clangula); Subfamily Dabbling ducks plus extinct (Anatinae); Family Waterfowl (Anatidae)
This bird appears across the great seas in the following continents: Europe, North America.
Deutschland: Zugvogel, Wintergast
Vocalization: Very vocal and distinct. Male: a pleasant resonant melodic "ahh-aaooee" in a yodeling, breaking triad. Starting with an accented first note (ahh), then gliding from first through second and third note (-aaoooeee). Far carrying. [Link]
Calls: Female: calls often, but less musical and distinct than male. [Link]
Physical details: length=40-47 cm, wingspan=40-47 cm, weight=550-900 g
Habitats: River and lake

🔍 No documented observation