He held posts at the
University of British Columbia and the
University College of North Wales, before returning to Oxford as a University Lecturer in Zoology, with a fellowship at
Wolfson College, Oxford, then Pembroke. He was elected a Fellow of the
Royal Society in 1984. From 2000 to 2005 he was the first chairman of the British
Food Standards Agency. On 15 February 2007, the
House of Lords Appointments Commission announced that he was to become a non-party political (
cross-bench) life peer. The peerage was gazetted on 28 March 2007 as
Baron Krebs, of
Wytham in the County of Oxfordshire. In 2005, Lord Krebs accepted the role of principal of
Jesus College, Oxford, a post he held until 2015. His speciality is
ornithology. His publications include more than 130 refereed papers, 5 books, and 130 book chapters, reviews, or popular pieces. They have introduced new methods to the science of ornithology, including the use of
optimality models to predict foraging behaviour, and, more recently, techniques from
neurobiology and
experimental psychology to assess the mental capacities of birds and to relate these to particular regions of the brain. In 2000, during his chairmanship of the Food Standards Agency, Krebs criticised the
organic food movement, saying that people buying such food were "not getting value for money, in my opinion and in the opinion of the Food Standards Agency, if they think they're buying food with extra nutritional quality or extra safety. We don't have the evidence to support those claims." Having led the Randomised
Badger Culling Trials, Krebs became one of the UK's leading experts on
bovine tuberculosis. The findings of the trials led him to oppose further badger culling in 2012 and he contributed to a paper on the subject written by centre-right think tank The
Bow Group. From 2006 to 2007, Krebs was a member of the
Nuffield Council on Bioethics, where he chaired the Working Party on
Public Health. He took up the chairmanship of the
National Network of Science Learning Centres in 2007. ==Lectures==