From an early age Gustav joined his father on outdoor trips collecting specimens of birds and small mammals.
Their home on Ziegelfeldstrasse known as the "Haus von Burg" became a centre for bird research, and the headquarters of the "Federal Ornithological Commission in Ölten".
He was a founding president of the Swiss Society for Ornithology and Bird Protection from 1909 but resigned from the position in 1913 when he was succeeded by Albert Hess.
He became a president of the health insurance company that his father had helped found and he supported a federal old-age and disability pension.
He also wrote on political topics and he criticized the German Wehrmacht and their actions in Belgium during the First World War.