Daniel Pauly Lecture

17 May 2018


Daniel Pauly by Alison Barrat

Fish Must Breathe!

A public lecture by Professor Daniel Pauly, Institute for the Oceans and Fisheries, University of British Columbia and 2018 UWA Institute of Advanced Studies Visiting Fellow.

One of the expected responses of marine fishes to ocean warming is decrease in body size, as supported by evidence from empirical data and theoretical modelling. The theoretical underpinning for fish shrinking is that the oxygen supply to large fish size cannot be met by their gills, whose surface area cannot keep up with the oxygen demand by their three-dimensional bodies. Although this logic has been recently challenged, it will be shown, in the context of Gill-Oxygen Limitation Theory (GOLT) that gills, because they must retain the properties of open surfaces, cannot avoid being limiting for fish growth. Also, besides explaining (1) the growth patterns of fish, a wide range of biological features of fish and other water-breathing organisms can be understood only when gill area limitation is used as an explanation, including (2) the decline of food conversion efficiency with size; (3) the size at which they reproduce; (4) the phenomenon known as ‘abortive maturation’; (5) why the fish of a given species are larger at the cold end of their distribution ranges; (6) why fish move into deeper/colder waters when they grow bigger; (7) why the growth and food conversion efficiency of farmed fish declines when oxygen supply is reduced; (8) why fish perform temperature-driven seasonal migrations (9) why global warming induces poleward migrations; (10) why the flesh of tuna that have fought for a long time at the end of a fishing line becomes inedible; (11) why the otoliths of fish and the statoliths of invertebrates form clear daily rings in larvae and juveniles, but in adults; (12) many other phenomena that are never ben elucidated before, or even perceived as requiring an explanation. The GOLT thus appears to have the potential of a powerful theory capable of acceleration progress in marine biology and limnology and the corresponding applied discipline, ie, fishery science and aquaculture. 

Professor Daniel Pauly is an internationally renowned fisheries expert and marine conservationist. Professor Pauly acquired a doctorate (1979) in Fisheries Biology from the University of Kiel. In 1994, after many years at the International Center for Living Aquatic Resources Management in Manila, Dr Pauly became Professor at the Fisheries Centre of the University of British Columbia, where he served as Director (2003-2008). In 1999, he became Principal Investigator of the Sea Around Us project, which is devoted to studying, documenting and promoting policies to mitigate the impact of fisheries on the world’s marine ecosystems. Professor Pauly is the author or co-author of over 1,000 scientific and other articles, books and book chapters on fish, fisheries and related topics. He is also co-founder of FishBase.org, the online encyclopedia of more than 30,000 fish species. 

Professor Pauly has received global recognition for his work. Most recently, Professor Pauly was appointed Chevalier de la Legion d’Honneur, France’s highest honour. His many other awards include the 2001 Murray Newman Award for Excellence in Marine Conservation Research, 2003 election as a Fellow of the Royal Society of Canada (Academy of Science) and in the same year, Scientific American listed him as one of the year’s “50 Research Leaders.” In 2004, he received the American Fisheries Society Award of Excellence, the Roger Revelle Medal from IOC/ UNESCO, and the Edward T. LaRoe III Memorial Award of the Society of Conservation Biology. In 2005, he received the International Cosmos Prize, from the Expo '90 Foundation, Japan, and in 2006, the Volvo Environment Prize (shared). In 2007, he received the Excellence in Ecology Prize from Inter-Research, Germany, the Ted Danson Ocean Hero Award from Oceana, and, in 2012, he received the Grand Prix 2011 of the French Ecological Society, and the Nierenberg Award for Science in the Public Interest for the Scripps Institution for Oceanography. He is the recipient of five honorary doctorates.