A painter of birds and animals in watercolours; draughtsman, wood-engraver, etcher and illustrator, Tunnicliffe studied at Macclesfield and Manchester Art Schools, winning a Royal Exhibition Scholarship to the Royal College of Art (1921-5). He then returned to Cheshire, moving to Anglesey in 1947. He exhibited at the Royal Academy, first as an engraver, then as a painter, becoming ARA in 1944 and RA in 1954. His work also appeared at the RE, in London and provincial galleries and abroad, and is represented in public collections. He illustrated more than 80 full-length books, published his own books and produced a variety of commercial work. He drew many post-mortem measured studies of birds which were exhibited at the RA in 1974. He was the Vice-President of the RSPB and their Gold Medal winner, and he received an OBE in 1978.