ABSTRACT
Many aspects of the biology of perch species Perca spp. can be productively studied by relatively short investigations, but the reproductive biology and longevity of these species are such that studies of their population biology and associated interactions require much longer-term observations. Even the three-year durations typical of many research studentships are too short for the collection of meaningful data in this context, leaving such studies to fi sheries organisations, research institutes or university groups that can facilitate much longer programmes of research. Although the benefi ts of longterm ecological studies in an era of major environmental change are now appreciated by scientists and managers alike and inform much current freshwater environmental management (Maberly and Elliott 2012), such value was not so readily apparent a few decades ago when there was a paucity of long-term data sets in the environmental sciences (Elliott 1990). Furthermore, not all have subsequently survived, making those that do persist even more valuable.
