The Continuous Plankton Recorder Survey of the North Pacific
  • Acronym: CPR
  • Term: summer 1997 - current
  • Co-ordinator Pacific CPR Survey: 2020-present, Clare Ostle (MBA,
  • Past Co-ordinator Pacific CPR Survey: 2000-2019, Sonia Batten (MBA/PICES,
The Continuous Plankton Recorder (CPR) was first deployed in the north Pacific in summer 1997 as a feasibility study carried out by the Sir Alister Hardy Foundation for Ocean Science (SAHFOS). Now CPR is a part of the Marine Biological Association of the UK (MBA). CPRs had been deployed for over 70 years in the north Atlantic from Ships-of-Opportunity, currently managed by SAHFOS, providing a wealth of time series data (Reid et al., 2003). In contrast, the open ocean areas of the north Pacific have been historically poorly sampled. Presentations were made at the 1998 annual North Pacific Marine Science Organisation (PICES) meeting and from this followed a recommendation that the CPR be used to address the lack of open ocean plankton data. The cost-effectiveness of ship-of-opportunity sampling, the tried-and-tested nature of the CPR and the growing recognition that zooplankton respond rapidly to climate change and also provide the link between changes in the atmosphere and important upper trophic level populations all provided the impetus for support for CPR sampling.

The first proposal was funded by the North Pacific Marine Research program to collect plankton samples in 2000 and 2001 and a third year, supported by the North Pacific Research Board (NPRB), followed on from this. Funding was also obtained in 2002 from the Exxon Valdez Oil Spill Trustee Council (EVOS TC) for the transect in the Gulf of Alaska and since then the NPRB has supported the ~6,500km transect running east-west across the north Pacific and the EVOS TC has supported the ~2,500 km north-south Gulf of Alaska transect. From 2000 to 2003 the north-south transect ran from Prince William Sound to California but was modified in 2004, when that ship was withdrawn, to a new transect from 2004 between Cook Inlet and Puget Sound. This transect is now in its 4th year of sampling.

Sampling on the east-west transect was enhanced in 2002 through collaborations with the Point Reyes Bird Observatory Conservation Science (Dr Bill Sydeman) and the Canadian Wildlife Service (Dr Ken Morgan) to make simultaneous observations of marine bird and mammal distributions. In 2004 a CTD was fitted to the CPR to additionally sample the physical environment (temperature, salinity and chlorophyll a as fluorescence).

In 2003 collaborative agreements were set up with the Prince William Sound Science Centre in Valdez and Fisheries and Oceans, Canada (the Institute of Ocean Sciences in Sidney, BC) to service and unload the CPRs locally. Initial sample processing is now carried out at IOS and a subset of samples are analysed within a few weeks of the ship’s return so that some data can be available quickly, to give an idea of current conditions. Full, quality controlled data are available within a year of collection. Although long term funding has not been secured the program is now in its 8th year of sampling and many studies have resulted from the data (see below). The program is overseen by the PICES CPR Advisory Panel and interest and enthusiasm to continue and extend the program is ongoing. The initial support from PICES and the NPMR program has therefore firmly set the foundations of a large scale monitoring program for the north Pacific.
Current status

The aim of these pages is to present some of the most recent data to show the current status of the plankton populations in regions of the North Pacific that are sampled by the CPR. These regions are (see map):

  1. the shelf waters west of British Columbia [BC Shelf];
  2. the offshore waters west of British Columbia [Oceanic NE Pacific];
  3. the Northern oceanic Gulf of Alaska [NGoA];
  4. the Western oceanic Gulf of Alaska [WGoA];
  5. the shelf waters southeast of Cook Inlet and including the mid and lower waters of Cook Inlet [Alaskan Shelf];
  6. the shelf waters through Unimak Pass in the Aleutian Islands [Aleutian Shelf];
  7. and the southern deep-water Bering Sea [S Bering Sea].

Data for the current year are presented as monthly means, superimposed on the long-term monthly mean and minimum/maximum monthly values found in the time series to date (for most regions since 2000). Open circles are PROVISIONAL data, based on 25% of the samples to be analysed, and numbers will change as more samples are processed and quality-controlled.
Filled circles are finalized data when all samples have been finalized and QCd.

Four variables have been selected
  • Total Diatom abundance
  • Mesozooplankton abundance
  • Estimated Mesozooplankton biomass (dry weight) and
  • Average Copepod Community Size (based on Richardson et al., 2006 where the published length of the adult female represents all individuals of the species).

These variables are believed to provide a useful summary of the plankton, but there are some caveats and limitations:

  • The CPR only semi-quantitatively captures diatoms, and is biased towards the larger, chain forming varieties, therefore this may only be a small portion of the phytoplankton community.
  • The number of samples that the provisional data are based on is small, especially for the smaller regions.
  • Regions with the best sample density are: Oceanic NE Pacific, Alaskan Shelf, and S. Bering Sea Three regions are sampled by the east-west transect only, which runs only three times a year in spring, summer and fall (W. GoA, Aleutian Shelf and S Bering Sea). It is difficult to study the seasonal cycle within the current year with just 3 data points (although comparisons with the long term monthly means are still valid).
Data will be updated several times a year - check back regularly for the latest information.
Time Series Data

[Data Analysis | Plankton Abundance | Species List | Zooplankton Biomass | Phytoplankton Colour Index | CTD Data]

Ten regions which reflect the different oceanographic provinces that are sampled by the two transects have been delineated (e.g. oceanic areas and shelf regions around the north Pacific rim, see Figure). Monthly averages of plankton indices can be calculated for each region, though it should be noted that not all regions have the same intensity of sampling. Data from the current or most recent year are provisional and have not yet been quality controlled – expect these data to change once sample analysis is complete . The following publications contain information on CPR sampling and sample analysis:

Batten, S.D., Clarke, R.A., Flinkman, J., Hays, G.C., John, E.H., John, A.W.G., Jonas, T.J., Lindley, J.A., Stevens, D.P., Walne, A.W. (2003) CPR sampling – The technical background, materials and methods, consistency and comparability. Progress in Oceanography 58, 193-215
Richardson, A.J., Walne, A.W., John, A.W.G., Jonas, T.D., Lindley, J.A., Sims, D.W., Stevens, D., and Witt, M. (2006). Using continuous plankton recorder data. Progr. Oceanogr. 68, 27-74

These web pages do not include all available CPR data – presence/absence data are not included, nor are data from samples in between these 10 regions. All Pacific CPR data are freely available however; for other data enquiries please contact Sonia Batten,

AKsh = Alaskan Shelf
AleutSh = Aleutian Shelf
CoastBC = Coastal British Columbia
CookIn = Cook Inlet
NEJap = North East Japan Shelf
NGoA = Northen Gulf of Alaska
Offshore BC = Offshore British Columbia
SouthBerSea = Southern Bering Sea
WGoA = Western Gulf of Alaska
WNPacific = Western North Pacific

CPR Methods

Espinasse, B., Hunt, B.P.V., Batten, S.D., and Pakhomov, E. (2019). Defining isoscapes in the Northeast Pacific as an index of ocean productivity. Global Ecology and Biogeography.

Stern, R., Trainer, V.L., Moore, S.K. and Batten, S.D. (2018) Spatial patterns of Pseudo-nitzschia genetic diversity in the North Pacific from Continuous Plankton Recorder surveys. Marine Ecology Progress Series.

Batten, S.D., Ruggerone, G.T. and Ortiz, I. (2018). Pink Salmon induce a trophic cascade in plankton populations in the southern Bering Sea and around the Aleutian Islands. Fisheries Oceanography.

Batten, S.D., Raitsos, D.E., Danielson, S.,Hopcroft, R.R., Coyle, K. and McQuatters-Gollop, A. (2018). Interannual variability in lower trophic levels on the Alaskan Shelf. Deep Sea Research II, 147, 58-68.

Fu, C., Olsen, N., Taylor, N., Grűss, A., Batten, S., Liu, H., Verley, P., and Shin, Y.-J. (2017) Spatial and temporal dynamics of predator-prey species interactions off western Canada. - ICES Journal of Marine Science.

Batten, S.D., Chiba, S., Edwards, M., Hall, J., Hosie, G., Melrose, C., Muxagata, E., Richardson, A.J., Verheye, H. M., Helaouet, P., Rochester, W., and Stevens, D. (2016). The Status of Zooplankton Populations. In: UNESCO IOC and UNEP. The Open Ocean: Status and Trends. United Nations Environment Programme (UNEP), Nairobi.

Batten, S.D., Moffitt, S., Pegau, W.S., and Campbell, R. (2016). Plankton indices explain interannual variability in Prince William Sound herring first year growth. Fisheries Oceanography 25, 420-432.

Yoshiki T, S Chiba, H Sugisaki, T Ichikawa, S Batten (2015) Northerly shift of warm-water copepods in the western subarctic North Pacific: Continuous Plankton Recorder samples (2001-2010), Fisheries Oceanography 24, 414-429.

Chiba S., Batten, S., Yoshiki, T., Sasaki, Y., Sasaoka, K., Sugisaki, H., and Ichikawa, T. (2014) Temperature and zooplankton size structure: climate control and basin-scale comparison in the North Pacific. Ecology and Evolution.

Batten, S.D., and Gower, J.F.R. (2014). Did the iron fertilization near Haida Gwaii in 2012 affect the pelagic lower trophic level ecosystem? Journal of Plankton Research, 39, 925-932.

Batten, S.D. (2013). Euphausiids in North Pacific Continuous Plankton Recorder sampling. Chapter 4 in: Report of Working Group 23 on Comparative ecology of krill in coastal and oceanic waters around the Pacific rim. Eds. Shaw, C.T., Peterson, W.T and Sun, S. PICES Scientific Report, 43, 100 pp.

Yoshiki, T.M., Chiba, S., Sugisaki, H., Sasaoka, K., Ono, T. and Batten, S. (2013) Interannual and regional variations in abundance patterns and developmental timing in mesozooplankton of the western North Pacific Ocean based on Continuous Plankton Recorder during 2001–2009. Journal of Plankton Research 35, 993-1008.

Chiba, S., Batten, S., Sasaoka, K., Sasai, Y., and Sugisaki, H. (2012). Influence of the Pacific Decadal Oscillation on phytoplankton phenology and community structure in the western North Pacific. Geophysical Research Letters 39, L15603.

Rooper, C.N., J.L. Boldt, S.D. Batten & C. Gburski. (2012). Growth and production of Pacific ocean perch (Sebastes alutus) in nursery habitats of the Gulf of Alaska. Fisheries Oceanography 21, 415-429.

Batten, S.D. and Walne, A.W. (2011) Variability in northwards extension of warm water copepods in the NE Pacific. Journal of Plankton Research 33, 1643-1653

Bond, A.L., Jones, I.L., Williams, J.C., and Byrd, V. (2011). Diet of auklet chicks in the Aleutian Islands, Alaska: similarity among islands, interspecies overlap, and relationships to ocean climate. Journal of Ornithology, volume 153, pages 115–129 (2012).

Batten, S.D. (2011) Continuous Plankton Recorders in the North Pacific Ocean, McGraw-Hill Yearbook of Science and Technology 2011.

W.J. Sydeman, S.A. Thompson, J.A. Santora, M.F. Henry, Morgan, K.H. and Batten, S.D. Macro-Ecology of Plankton-Seabird Associations in the North Pacific Ocean (2010). Journal of Plankton Research. 32(12): 1697-1713

Roberta C. Hamme, R.C., Webley, P.W., Crawford, W.R, Whitney, F.A., DeGrandpre, M.E., Emerson, S.R., Eriksen, C.C., Giesbrecht, K.E., Gower, J.F.R, Kavanaugh, M.T., Peña, M.A., Sabine, C.L., Batten, S.D., Coogan, L.A., Grundle, D.S., Lockwood, D. (2010). Volcanic ash fuels anomalous plankton bloom in subarctic Northeast Pacific. Geophysical Research Letters, VOL. 37, L19604, a href="" target="_blank">, 2010.

Batten, S., Chen, X., Flint, E.N., Freeland, H.J., Holmes, J., Howell, E., Ichii, T., Kaeriyama, M., Landry, M., Lunsford, C., Mackas, D.L., Mate, B., Matsuda, K., McKinnell, S.M., Miller, L., Morgan, K., Peña, A., Polovina, J.J., Robert, M., Seki, M.P., Sydeman, W.J., Thompson, S.A., Whitney, F.A., Woodworth, P., Yamaguchi, A. 2010. Status and trends of the North Pacific oceanic region, 2003-2008, pp. 56-105 In S.M. McKinnell and M.J. Dagg. [Eds.] Marine Ecosystems of the North Pacific Ocean, 2003-2008. PICES Special Publication 4, 393 p.

Batten, S.D., and Mackas, D.L. (2009) Shortened duration of the annual Neocalanus plumchrus biomass peak in the Northeast Pacific. Marine Ecology Progress Series. 393, 189-198.

Lindley, J.A., and Batten, S.D. (2008) Distribution and seasonal cycles of decapod crustacean larvae in Continuous Plankton Records from the North Pacific Ocean. Journal of the Marine Biological Association of the United Kingdom. Vol. 88 (03) 443-451.

Mackas, D.L., Batten, S.D., and Trudel, M., (2007) Effects on zooplankton of a warming ocean: recent evidence from the Northeast Pacific. Progress in Oceanography, 75, 223-252

Batten, S.D. and Freeland, H.J. (2007). Plankton populations at the bifurcation of the North Pacific Current. Fisheries Oceanography, 16, 536-646.

Kirby, R.R., Lindley, J.A., and Batten, S.D. (2007). Spatial heterogeneity and genetic variation in the copepod Neocalanus cristatus along two transects in the North Pacific sampled by the Continuous Plankton Recorder. Journal of Plankton Research 29, 97-106

Batten, S.D., Hyrenbach, K.D., Sydeman, W.J., Morgan, K.H., Henry, M.F., Yen, P.Y. and Welch, D.W. (2006). Characterising Meso-Marine Ecosystems of the North Pacific. Deep Sea Research II, 53, 270-290.

Batten, S.D and Crawford, W.R. (2005). The influence of coastal origin eddies on oceanic plankton distributions in the eastern Gulf of Alaska. Deep Sea Research II, 52, 991-1009.

Lindley, J.A., Batten, S.D., Coyle, K.O and Pinchuk, A.I. (2004). Regular occurrence of Thysanoessa inspinata (Crustacea: Euphausiacea) in the Gulf of Alaska. Journal of the Marine Biological Association of the UK, 84, 1033-1037.

Batten, S.D. and Welch, D.W. (2004). Changes in oceanic zooplankton populations in the North-east Pacific associated with the possible climatic regime shift of 1998/1999. Deep Sea Research II, 51, 863-873.

Batten, S.D., Welch, D.W., and Jonas, T. (2003). Latitudinal differences in the duration of development of Neocalanus plumchrus copepodites. Fisheries Oceanography, 12 (3), 201-208.