He moved from Cape Town to Durban shortly before the outbreak of the Boer War and travelled to England in 1899 to oversee the printing of the first volume of his ornithological work, "The Birds of South Africa". The completed series was meant to form part of a wider project under the editorship of William Sclater, director of the South African Museum, describing the fauna of southern Africa. Stark returned to the Colony of Natal in September, 1899, where he volunteered as medical officer for the British forces when the Boer War broke out.