My Fellowship in 1987 examined the problem of acid rain in North America, at that time a major pollution concern. Inspired to address similar issues elsewhere, I have since published over 300 scientific papers on global change effects on freshwater ecosystems. Recognition for my work includes Fellowships of the Chartered Institute of Ecology and Environmental Management (CIEEM), Learned Society of Wales, Royal Society of Biology and the Freshwater Biological Association, while my Marsh Award for Marine and Freshwater Conservation from the Zoological Society of London described me as "one of the leading applied freshwater ecologists of his generation".

My public service has included roles as Chairman and Vice-President of the Royal Society for the Protection of Birds (RSPB), Chairman of Science Development for the UK Centre for Ecology and Hydrology, Chairman of Welsh Water's Environment Advisory Panel, Chairman of the invertebrate charity Buglife, Deputy Chairman of Natural Resources Wales, member of the UK Joint Nature Conservation Committee, President of CIEEM, and board roles with several environmental charities.

I am currently professor of ecology at Cardiff University where I have spent over 40 years.