Where did the water come from and where does it go?

These are the main questions we are trying to answer to help us better understand near-surface ocean circulation. Being able to answer these questions has applications in navigation, pollution monitoring and abatement, search and rescue, and plankton and clam larvae drift.

One way to better understand near-surface ocean circulation is to deploy surface drifters - these come in various designs and are placed in the ocean with their location tracked as they drift along with the prevailing surface currents, wind, and waves. Drifters of various kinds have been deployed by Fisheries and Oceans Canada in the Pacific Ocean since the 1950's. One of those early drifters - a simple message in a bottle - was recently found in 2016. More pictures of this bottle are here and here. This was drift bottle No. 25263, one of 33449 bottles released over a four year period, detailed in this report. Finders of the drift bottles were guaranteed a reward of $1.00 no matter where the card inside the bottle was sent from, and some recoveries were made as far as 1500 km away.

Here we document a drifter program that began in 2014 that has involved drifter deployments throughout the Northeast Pacific Ocean, but has also included a few in the Northwest Atlantic Ocean, Western Arctic Ocean, Norway, Taiwan, and the Southern Ocean.

Found a Drifter?

Have you found a drifter? Does it look like this?

Surface Circulation Tracker (SCT)
Surface Circulation Tracker (SCT)
OSKER with drogue

If the drifter is floating freely in the ocean, please LEAVE IT ALONE. It is probably collecting data and reporting its location back to us via satellite. If you can, please take a picture and send it to us, along with where and when you saw it to spongiam.oceanus@gmail.com.

If the drifter is floating in the ocean but tangled up in flotsam, please untangle it, (reshape the round aluminum tubes below the waterline if necessary in the case of an SCT drifter,) and put it back in the water. If you can, please take a picture and send it to us, along with where and when you saw it to spongiam.oceanus@gmail.com.

If the drifter is washed up on the shore, please recover it so we can recycle it. If you can, please take a picture and send it to us, along with where and when you recovered it to spongiam.oceanus@gmail.com. We will send you a prepaid envelope so you can send the drifter back to us. (In the case of an SCT drifter, we only wish to recover the SPOT Trace and plastic bracket that holds it. These are the black plastic parts on top of the spring on top of the drifter. The rest of the drifter can be disposed of in the municipal waste.)

Many thanks for your help!

For more information on the program you can see this news story: https://www.saanichnews.com/news/hundreds-of-floating-sponge-bobs-help-track-ocean-currents/

Drifter Recoveries

Drifter recoveries in the news:

On the Powell River story, above, see also:

Drifter Tracks

You can search and display drifter tracks (and access the data) here: https://dmapps.waterproperties.ca/en/drifter/.

You can also access the drifter track data through the Water Properties website: https://www.waterproperties.ca/data/. Select Data, Search Data Holdings, and from the Metadata panel, select Metadata Name=Data Description, Value=Drifting Buoy. Note that you will need an account to access the data and the data are not available in real-time.

Below are shown annual summaries of drifter tracks.

Drifter Tracks in Google Earth

Drifter tracks can also be displayed in Google Earth. Tracks have been separated by year into kmz files, and are displayed in three different ways:

  1. As simple tracks with each track a different colour.
  2. As above with but beginning, ending, and possible found locations also indicated.
  3. As animated gx tracks.

Drifter Publications

Frequently Asked Questions


Plotting software courtesy of R. Pawlowicz:
Pawlowicz, R., 2020. "M_Map: A mapping package for MATLAB", version 1.4m, [Computer software], available online at https://www.eoas.ubc.ca/~rich/map.html.

Drifter data processed using drifteval software provided by R.Pawlowicz, see:
Pawlowicz, R., Hannah, C. and Rosenberger, A., 2019. Lagrangian observations of estuarine residence times, dispersion, and trapping in the Salish Sea. Estuarine, Coastal and Shelf Science 225, p.106246.


Roy Hourston
Drifter Program Coordinator - Pacific Region
Fisheries and Oceans Canada
Institute of Ocean Sciences
9860 West Saanich Road, P.O. Box 6000
Sidney, B.C., V8L 4B2
Email: spongiam.oceanus@gmail.com or Roy.Hourston@dfo-mpo.gc.ca
Web: http://www.pac.dfo-mpo.gc.ca/science/facilities-installations/index-eng.html#ios

Page last updated: May 3, 2023.