Charles Leopold Layard Biden was the son of William Henry Charles Biden and his wife Marion Jane, born Atmore, who was a niece of Edgar Leopold Layard*, a former director of the South African Museum. Charles was educated at the Grey Institute (a high school) in Port Elizabeth. He entered the civil service of the Cape Colony on 7 August 1901 as a clerk in the magistrate's office at Port Nolloth, as well as clerk and examining officer of customs at Hondeklip Bay. While holding these positions he sent many insects and reptiles from Namaqualand to the South African Museum.
After the formation of the Union of South Africa in 1910 Biden was transferred to Cape Town as third grade examining officer in the Statistical and Audit Office of the Department of Customs and Excise. Residing at Kalk Bay, he continued to contribute specimens to the South African Museum. In 1939 he was appointed as acting shipping master at Port Elizabeth. He was an enthusiastic fisherman and collector of fisherman's records and stories, and published a popular book, Sea-angling fishes of the Cape: A natural history of some of the principal fishes caught by sea-anglers and professional fishermen in Cape Waters (2nd ed., Cape Town, 1948; 3rd ed., 1954). However, his main interest was sharks, and he spent much time collecting measurements and information about the species found in South African waters. He continued this work even after being transferred to Johannesburg and, particularly after his retirement, regularly visited fishing centres all along the South African coast. Every shark specimen he met with was meticulously measured and photographed, showing its mouth, nostrils, gill-slits, mucous-pores and other details. Much of this information was sent to two shark specialists in the United States, Henry B. Bigelow and William C. Schroeder, who gave him every encouragement. His intention was to publish a book on South African sharks, but it was still incomplete at the time of his death. He was survived by his wife, May Lenton Barber, with whom he had two children.