In 1960 it was rated the all-time best seller in Australian natural history and remains a classic birding reference to this day.
Cayley's family moved to Sydney in the mid-1890s, where he studied art and was a pivotal member in the Cronulla Surf Life Saving Club.
[2] His paintings were regularly published in the Royal Australasian Ornithologists’ Union's quarterly journal The Emu,[3] and he wrote popular articles on birds for the weekly Sydney Mail.
From about 1918 until the time of his death in 1950, Cayley was painting subspecies, plumage stages and eggs (now lost) for the entire range of known Australian birds.
In 1984, noted ornithologist Terence Lindsey picked up where Cayley had left off, incorporating these illustrations into a revised and expanded edition of What Bird is That?
[7] Cayley was long associated with the Gould League of Bird Lovers of New South Wales and was made an Honorary Life Member in 1935.
The scholarship was eventually extended to post-graduate students involved in wildlife study or management relating to birds from universities around Australia.