Greenland shark tagging:

As part of a project studying the biology of the Greenland shark (Somniosus microcephalus) several specimens have tagged tagged with Floy tags as well as satellite pop-up tags in different areas:

1: Disko bay in the vicinity of University of Copenhagen's Arctic Station - from R/V Porsild in May 2011 and May 2014.

2: Ammassalik Fjord in South Eastern Greenland during a cruise with DTU-Aqua's R/V Dana in September 2012.

3: The area from Scoresbysund Fjord to Danmarkshavn from Univ. of Tromsø's R/V Helmer Hansen in August 2013.

4: The area from Uumanaaq to north of Upernavik  during a cruise with R/V Sanna in August/September 2014.

WE WILL PAY YOU A REWARD OF 500,- Danish Kr. if you find one of our sattelite or Floyd tags on a Greenland shark and return the tag to us.

NEWS: On January 2015 one of our sattelite pop-up tag was found on Fistral Beach, Newquay, Cornwall, England by Fiona Knight. The tag that was attached to a shark close to Ammassalik on September 2012. It was programmed to release 9 months later in june 2013 and did so approximately half-way between Iceland and Greenland. When it surfaced it uploaded data via the Argos sattelite until the battery ran out a week later. Since then the tag drifted with the currents in the North Atlantic - most likely along this route. It is extremely good news that the tag was discovered as there are still lots of storred data that can we can access. 

Link to YouTube video from the research cruise in September 2012 - tagging a shark in foul weather.

We used Floy Tags model FH-69

If you find one of these tags, please contact me with information concerning when and where and how you caught the shark, and if possible please add information concerning total length, girth, body mass (which may be an impossible task), and if the shark had parasites on one or both eyes.

    John Fleng Steffensen, Professor

    University of Copenhagen, Marine Biological Section

    Strandpromenaden 5, DK-3000 Helsingør, Denmark

    Phone: +45 353 21 950; Cell phone: +45 60770490; e-mail:

    In return we will inform you concerning where and when the shark was tagged.

   You will get a reward of 500,- Danish Kr. when we receive the original tag and the above information.

None of the approximately 50 sharks we have relased so far have been recaptured yet.

Some sharks were also tagged with a Wildlife Computers, or Desert Star satellite pop-up tags i all 4 areas.

These tags  record temperatue and depth as well as ligth levels (=> sunrise and sunset = proxy for geo-coordinates) and can be programmed to release from the animal and pop-up at a specific date. When floating at the surface the tag will start transmitting the stored data via the Argos satellite, and forward the data to us. The battery will last for about a week, which normally is plenty for transmitting all the data, after which the tag goes silent and is lost. We have programmed tags to release after 3, 6 and 12 months.

4 sharks relesed in Disko bay in may 2011 all poped up about a 1000 km furtner north close to Thule 3 months later.

1 shark released in Ammassalik Fjord September 2012 popped up in March 2013 no more than about 100 km from where it was released. Another tag supposed to pop up as well never reported back, possibly because it has been trapped under the ice. Link to more info.

One of the tags from Ammassalik Fjord September 2012 popped as scheduled about 6 month later in an area north of the polar circle and transmitted most of the data. About 1,5 years later a beachcomber in Cornwall, UK found the tag on the bach after a long jorney drifting south along the Greenland easy coast, then up along the west side of Greenland to the Baffib Bay, then south along Baffin Island, Canada and down to maybe Virginia before it was caught by the Gulf Current that brought it to the beach in Cornwall. When we got the tags we could download the remaing data. 

Update January 2019: During the last 7 years we have tagged more than 100 Greenland sharks with Floyd ID-sphagetti tags, but have no returns yet! Wonder where they are!

The project is financially supported by National Geographic Society, Save Our Seas Foundation, the Carlsberg Foundation, the Danish Centre for Marine Research, The Commission for Scientific Research in Greenland, TUNU-Mafig (Marine Fishes of North East Greenland) and the Danish Council for Independent Research (Old And Cold).

This page:

January 2019