Continuous Plankton Recorder


The Continuous Plankton Recorder is a device developed by Sir Alister Hardy in 1931. Since then, his effort has been standardized and continued by the Sir Alister Hardy Foundation for Ocean Science. Research and merchant ships are equiped with a planton recording device that is towed near-surface for up to 300 nautical miles. During the traul, plankton is sieved out of the water and stored by a silk cloth that is then analysed for plankton biomass and species at SAHFOS. The plankton recorders are now widely availbale and in use providing an extremely large, and 'continuous' data set for the Atlantic Ocean.


Dataset Location: OBIS Continuous Plankton Recorder (Phytoplankton); OBIS Continuous Plankton Recorder (Zooplankton)

Full species lists:

Green-ness values and Calanus finmarchius abundance per region:

Temperature data:

Site Location: northern Atlantic Ocean
Site(s) Georeferenced: Yes

Timespan: 1946 - 2011

Sampling Frequency: Continuous towing data is summarized by month.

Data collection summary/Methods: Data is collected on a network of shipping routes from merchant or research vessels that tow a plankton sampling device about 10m in depth. The device includes a 270 micron mesh silk cloth that collects and stores plankton during a 10 - 500 nautical mile tow. The silk is then removed from the towing device and sent to the laboratory. At the lab, the silk is cut into 'blocks' that represent 10 nauthical miles of towing. Each block is then analysed for 'green-ness', 'plankton field analysis', 'zooplankton transverse analysis', and 'zooplankton eye count analysis'. For more information see: 

'Green-ness' is a value determined by comparing the silk to a color chart (0, no green; 1, very pale green; 2, pale green; 6.5, green).

'Plankton Field Analysis' is the identification and count of phytoplankton under high power magnification for 0.001 of the silk block.

'Zooplankton Transverse Analysis' is the identification and count of zooplankton at low magnification for 0.02 of the silk block.

'Zooplankton Eye Count Analysis' is the identification and count of zooplankton > 2mm for the whole silk block.

Data collected: silk green-ness, species id, species count, location, temperature, salinity, nitrate, oxygen, phosphate, silicate

Known Issues: The sname and tname columns are not the same as in other OBIS datasets.

depth == 7.5 for every record.
Best Practices: Download the datasets seperately, as the dowloader software is overloaded with the combined datasets.

Conditions for use: Data Policy Statement:

First, they say:

This policy recognises the benefits of providing free and open access to good quality data...The aim of the new policy is to encourage the widest possible use of SAHFOS data and products, in order to best realise their potential value.

Then, in the 'Open Access' section:

Enquiries for access... should... be made to the SAHFOS Data Manager [to sign] terms and conditions [contract]. Access to CPR data and samples are free.

Charges levied for non commercial applications will be restricted to bench fees and costs involved in processing requests.

Applications from commercial organisations will be levied service charges... and royalties...

It is intended that processed data and some new near real-time data will be made freely available on the web... but access to the whole dataset will only be available to scientists coming to work at SAHFOS.

And, in the 'Licencing' section:

To gain access to SAHFOS data or products all researchers will be required to complete and sign a SAHFOS Data Licence Agreement.

And, yet it's 'freely available' and 'open-access' on OBIS:

Citation/ Distributing Author: Continuous Plankton Recorder (CPR) data (phytoplankton / zooplankton) from the Sir Alister Hardy Foundation for Ocean Science (SAHFOS). Available from [Accessed DATE]
Supplemental resources: 

Batten, S.D. and Clarke, R. and Flinkman, J. and Hays, G. and John, E. and John, A.W.G. and Jonas, T.D. and Lindley, J.A. and Stevens, D. and Walne, A. (2003) CPR sampling: the technical background, materials and methods, and issues of consistency and comparability. Progress in Oceanography, 58. pp. 193-215. ISSN 0079-6611

Reid, P.C. and Colebrook, J.M. and Matthews, J.B.L. and Aiken, J. (2003) The Continuous Plankton Recorder: concepts and history, from Plankton Indicators to undulating recorders. Progress in Oceanography, 58. pp. 117-173. ISSN 0079-6611

Richardson, A.J. and Walne, A.W. and John, A.W.G. and Jonas, T.D. and Lindley, J.A. and Sims, D.W. and Stevens, D. and Witt, M. (2006) Using continuous plankton recorder data.
Progress in Oceanography
, 68 (1). pp. 27-74. ISSN 0079-6611

Available via the EcoData Retriever: No

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