She was accompanied by her mother whose presence was necessary to satisfy the requirements of David Anstey , chief warden . He was concerned for their safety ; Tanzania was `` Tanganyika '' at that time and a British protectorate . She was accompanied by her mother whose presence was necessary to satisfy the requirements of David Anstey , chief warden , who was concerned for their safety ; Tanzania was `` Tanganyika '' at that time and a British protectorate .