Danube name meaning "strong, swift" (akin to Sanskrit "iṣiras" "swift"). In Latin, the Danube was variously known as ' or as '. The Dacian/Thracian name was "Donaris" for the upper Danube and "Istros" for the lower Danube. The Thraco-Phrygian name was "Matoas", "the bringer of luck". The Latin name is masculine, as are all its Slavic names, except Slovenian, (the name of the Rhine is also masculine in Latin, most of the Slavic languages, as well as in German). The German "Donau" (Early Modern German "Donaw, Tonaw", Middle High German "Tuonowe") is feminine, as it has been re-interpreted as containing the
Birds of the Danube Delta and mixed form of colonial nesting. Such an observation and interpretation of the colonial nesting origin in the Danube Delta may constitute an argument for properly explaining the colonial nesting phenomenon in different regions or the globe. Birds of the Danube Delta Following an almost two-decade (1951–1970) research of the Danube Delta territory, 274 bird species were identified of which 176 were brooding (sedentary and migratory) and 98 non-brooding ones (winter, passage, erratic, and accidental birds). The species of brooding birds occurring in the Danube Delta were classified into 12 main biotopes, the classification criterion being represented by the nesting