About Heinz Sielmann
Heinz Sielmann was a German wildlife photographer, biologist, zoologist and documentary filmmaker. Sielmann's first film, in 1938, was the silent movie Vögel über Haff und Wiesen (Birds over Curonian Lagoon and meadows), partially made in the Memelland which at the time was under Lithuanian control. Sielmann was awarded the Royal Geographical Society's Cherry Kearton Medal and Award in 1973.
Biography source: Wikipedia. The profile adds birthday-specific historical context from the Celebs Birthday Today editorial database.