Hans Christian Cornelius Mortensen

Who was Hans Christian Cornelius Mortensen?

Hans Christian Cornelius Mortensen was a Danish teacher and ornithologist. He was the first to employ bird ringing for scientific purposes.

Mortensen was born in Jonstrup on the island of Zealand, Denmark. After completing secondary school in 1874 he began studies in first theology and later in medicine and zoology at the University of Copenhagen without finishing any of these studies. He then worked as a schoolteacher at different schools in the Copenhagen area before, in 1888 and despite the lack of a university degree, became a master at the High School of Viborg in Jutland where he stayed for the rest of his life. From 1909 he held the post as a senior master. In 1891 he married Ingeborg Lemming, a fellow teacher and feminist who assisted him with his bird ringing. The couple had no children.

Mortensen's first successful experiments with bird ringing took place in 1899 with Common Starlings. Most were caught in nest boxes with an automatic closing mechanism. Later he also ringed White Storks, herons, gulls and various species of duck. It is said that he personally ringed more than 6000 birds during his lifetime.