Southern rockhopper penguin eye. The rockhopper penguin complex is confusing. Many taxonomists consider all three rockhopper penguin forms subspecies. Some split the northern subspecies ("moseleyi") from the southern forms ("chrysocome" and "filholi"). Still others consider all three distinct. The subspecies recognized for the southern rockhopper penguin complex are: The northern rockhopper penguin lives in a different water mass than the western and eastern rockhopper penguin, separated by the Subtropical Front, and they are genetically different. Therefore, northern birds are sometimes separated as "E. moseleyi". The rockhopper penguins are closely related to the macaroni penguin ("E. chrysolophus") and the royal penguin ("E. schlegeli"), which
What Bird is That? all-time best seller in Australian natural history and is still in print today. While sales and stature of Cayley’s original collection continued to grow, the prolific artist and ornothologist Cayley was working on a much more ambitious project – his so-called “big bird book”. From about 1918, he was creating illustrations of subspecies, plumage stages and eggs (now lost) of all known Australian birds. The project was incomplete at the time of his death in 1950, although the illustrations were all but finished. The ornithologist Terence Lindsey revived Cayley’s plans in the 1980s, creating the last and most significant revision