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In October 2003, 200 Sebastes mentella were tagged with the Underwater Tagging Equipment (UTE) made by Star-Oddi, about 150 nautical miles Southwest of Reykjanes-Ridge, on the research vessel Bjarni Sæmundsson by the Marine Research Institute in Iceland (MRI). By now, 2 fishes have been recaptured, the first only 4 days after tagging. As the first tag was observed during processing of the fish, no information about the recapture place or the condition of the fish is available.
On January 21 a second fish was recaptured only 2.2 nautical miles from the area where it was tagged. According to Thorsteinn Sigurdsson the project manager from MRI the fish was tagged on October 25 at a depth of 504 meters. When recaptured, the fish was 40 cm in length and 830 grams in weight. It was a mature female with developed ovary, and would probably have spawned in March if it had not been caught now. When investigating the fish, nothing visibly indicated that the fish was any different from untagged fish of this size and time of the year. Therefore we conclude that the tagging did not affect its life expectancy much compared with untagged ones. Injuries due to the tagging had started to heal and there were no indications of swelling around the wound. Furthermore, no indications of internal damages due to the tagging were observed. 
The main reason for MRI's interest is associated with the unknown stock structure of Sebastes mentella redfish, stock components in the Irminger Sea and along the shelf and slopes of Iceland, Greenland and the Faeroe Islands. As long as the stock structure and possible interrelation between possible stock components remain unknown, it will always be difficult to assess the status of the stock(s) and to give reliable advice on how to manage this important resource.
The UTE is made by Star-Oddi in cooperation with the MRI in Iceland and altogether, the tagging equipment definitely seems to work as expected. In June 2004, a 2-week cruise is planned for further tagging.
Learn more about the Underwater Tagging Equipment
Star-Oddi has developed a pressure (depth) sensor for measuring ocean depths down to 2000 m (200 bar), DST centi-hp. The intention is to further develop the sensor for greater depths! The high pressure sensor DST centi HP (high pressure), records temperature in addition to the depth. The sensor is a result of Star-Oddi expertise with in the field of material technology.
The memory size can be extended to 262,000 measurements (131,000 paired measurements of temperature and depth). Battery typically lasts 4-5 years. The DST is available with a protective polyurethane plastic housing for harsh conditions (see picture).
The new high pressure sensor DST centi HP will be used as a fish tag on Greenland Halibut later this month, a fish specie that spends most of its time at depths larger than 1000 m.
Examples of studies where the high pressure sensor can play a major role:
- Tagging of deepwater fish and marine animals that migrate to large depths
- Monitor fishing gear
- Monitor research equipment
- Stand alone monitoring instrument
- Industrial monitoring:
- Hydrolic
- Pressure tanks
- Following pressure and temperature of samples at high pressure
The DST centi-hp is 48 mm in length and 16 mm in diameter.
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