Prof Les Underhill has been Director of the Animal Demography Unit (ADU) at the University of Cape Town since it started in 1991. Although citizen science in biology is Les’s passion, his academic background is in mathematical statistics. He was awarded his PhD in abstract multivariate analyses in 1973 at UCT and what he likes to say about his PhD is that he solved a problem that no one has ever had. He soon grasped that this was not the field to which he wanted to devote his life, so he retrained himself as an applied statistician, solving real-world problems. He climbed the academic ladder from Lecturer to Professor in the Department of Statistical Sciences at UCT. Since his retirement, he has been a Senior Research Scholar. Gradually the application of his statistics narrowed down to data analysis problems in biodiversity and took him into the field of statistical ecology. The initial research focus of the ADU was on birds, starting with the first bird atlas project; it rapidly broadened to cover other groups such as mammals, butterflies, frogs, fish, reptiles and dragonflies. This millennium, Les has supervised or co-supervised 22 MScs and 30 PhDs, and mentored 17 post-doctoral fellows. The word cloud shows that he is the most prolific author of papers on birds in Africa for the period 1990–2016 (Colin Beale, Ostrich, 2018). He has a collection of four gold medals: Herschell Medal of the Royal Society of South Africa (1999), SANCOR Gilchrist Memorial Medal for contributions to marine science (2002), Oppenheimer Memorial Fellowship (2012) and BirdLife South Africa’s Gill Memorial Medal for a lifetime of outstanding service to ornithology (2017).