He has been director of Southern Cross University National Marine Science Centre since 2009.
During his research studies, where he first worked as a CSIRO post-doctoral fellow and then as the recipient of Queen Elizabeth II fellowship, he demonstrated that 4500 species of the world's songbirds had its origin in Australia.
[2] Les Christidis was Senior Curator of Ornithology at the Museum Victoria from 1987 to 1996.
Les Christidis was author or co-author of over 100 scientific papers and books on the taxonomy and evolutionary genetics of birds, bats, marsupials, bryozoans and more recently on cultural intangible heritage.
Together with Richard Schodde he described Amytornis barbatus diamantina, a subspecies of the grey grasswren, in 1987.