The Continuous Plankton Recorder:concepts and history, from Plankton Indicator to undulating recorders

• Published in: Progress in Oceanography
• Main Authors: Reid, P. C., Colebrook, J. M., Matthews, J B L, Aiken, J
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2003
• Subjects: GEOGRAPHICAL-DISTRIBUTION; POPULATION-DYNAMICS; ZOOPLANKTON ABUNDANCE; LARGE-SCALE PATTERNS; Oceanography; TIME-SERIES; CALANUS-FINMARCHICUS; DIEL VERTICAL MIGRATION; LONG-TERM CHANGES; DECAPOD CRUSTACEAN LARVAE; EASTERN NORTH-ATLANTIC; Calanus finmarchicus; North Atlantic
• Online Access: https://pure.uhi.ac.uk/en/publications/702280a9-1ecc-47d2-a7b7-94e10183d42c; https://doi.org/10.1016/j.pocean.2003.08.002

Alister Hardy conceived the Continuous Plankton Recorder (CPR) survey in the 1920s as a means of mapping near-surface plankton in space and time, interpreting the changing fortunes of the fisheries and relating plankton changes to hydrometeorology and climatic change. The seed he planted has grown to become the most extensive long-term survey of marine organisms in the world and the breadth of his vision becomes ever more apparent. The survey has now run for over 70 years and its value increases with every passing decade. Operating from 'ships of opportunity' the machines used are robust, reliable and easy to handle. Wherever possible, all the sampling and analytical methods have not been changed to maintain the consistency of the time series. Computerisation and the development of new statistical approaches have increased our ability to handle the large quantities of information generated and enhance the sensitivity of the data analyses. This overview, based on almost 900 papers, recounts the various phases in the history of the survey. It starts with the Indicator Survey (1921-1934), the deployment of the first CPR on the Discovery Expedition (1924-1927) and the early CPR survey in the North Sea (1931-1939). The survey reopened in 1946 after the Second World War and expanded across the North Atlantic to North America from 1959. Taxonomic studies were initiated and an emphasis was placed on patterns of distribution, which were seen to reflect the varying oceanographic conditions. The years 1968-1976 saw further expansion with operations even in the American Great Lakes, publication of a Plankton Atlas and initial evidence for a downward trend in plankton biomass. At about this time electronic instrumentation was attached to CPRs to make additional measurements and work was started on the development of a new generation of undulating Continuous Plankton and Environmental Recorders (CPERs). In 1976 the survey moved to Plymouth. Scientific priorities in the UK changed in the subsequent decade and funding became ...