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In October 2001 the Institute of Marine Research in Norway started an extensive tagging of deepwater Greenland halibut in the Barents Sea, mostly using conventional tags (Floy tags). Data Storage Tags (DST) were also used in some occasions. All in all 300 Greenland halibut tagged with DSTs were released on the shelf slope at the opening of the Barents Sea to the Norwegian Sea during autumn and winter in 2001, 2002 and 2003.
Until now 12 of these have been recaptured, the two tags with the longest recording periods had records for 23 and 11 months respectively.
The DST centi tags were programmed to record temperature and depth once an hour during the day, but one hour each day every tenth minute was recorded. The two longest data series were from intermediate sized females. The two tags showed a consistent seasonal pattern of activity in the depth-temperature field, and for the tag recording two years the second year was more or less an exact replica of the first year.
This Greenland halibut seemed to have relatively stable behaviour during the winter and spring with relatively small variation in depth and temperature (except long term).
Here you can download a PDF file with more information about the Greenland halibut project and other interesting findings from the DST archival tags from Star-Oddi.
Little is known about the behaviour of sea turtles in their foraging areas because they spend most of the time submerged and hidden from sight. This lack of information makes it difficult to devise measures to protect threatened and endangered turtles from collisions with boats, although boat strikes cause significant turtle mortality in some coastal areas. 
A research project conducted by Julia Hazel, a PhD candidate at James Cook University in Townsville, Australia, seeks to alleviate this problem. Julia has started investigating the daily activity of individual green turtles (Chelonia mydas) using data storage tags from Star-Oddi (DST milli) and ultrasonic transmitters (CHP-87-L) from Sonotronics.
Operating from a small boat, Julia searches for ultrasonic signals with a directional hydrophone. On detecting a signal she identifies the unique frequency/code combination of each transmitter and then determines the location of the submerged turtle by triangulation of compass bearings taken in quick succession from two different observation points.
Each data storage tag automatically records the turtle's depth and surrounding water temperature at 15-second intervals, but before Julia can download the archived data she faces the challenge of recovering each recorder without recapturing the turtle. She has designed custom floats that rise to the sea surface after being released by a fast-corroding metal link (photo above). Thereafter recovery depends on the small float being found either by the researcher or by a member of the public - luck is an essential element!
The Icelandic Fisheries Exhibition is the largest product and service show held in Iceland, there were nearly 800 exhibitors coming from more than 35 countries worldwide attending the 4 day show. Star-Oddi was presented with an award "Outstanding Icelandic Supplier". The awards were set up to recognise achievement both within the Icelandic fishing industry and internationally. Among the 13 winners were Simrad from Norway, Marel from Iceland, Hampidjan from Iceland, Baader from Germany and Nesco Weighing from UK.
Meet us in London!
-Oceanology International 2006
# Boot 926

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