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The new DST compass measures additionally to temperature and depth, relative directional movements of the DST, with reference to the magnetic north. The measuring parameters are measuring the magnetic field in two directions:
The picture shows the measuring range of the sensor relative to the DST housing.
The compass has +/-1° accuracy, the user can program it to show directions in eight, sixsteen point compass, or in degrees.
The DST compass allows the scientist to take frequent sampling of the direction of the fish, or the subject using different sampling intervals.
The performance of the DST compass is optimum when positioned in a horizontal plan.
Click here for product overview and technical specifications for the DST Compass Logger
Data storage tags (DST) from the Star-Oddi company have been used in Iceland for several years for tagging fish. Star-Oddi has started production of the DST-micro tag, that allows tagging of large smolts (80 - 100g). The DST-micro measures temperature and depth at selected time intervals and makes it possible to use temperate measurement for geolocation as well.
The aims of using DST micro tags are to increase knowledge on the whole marine life cycle of the salmon, from the time the smolts migrate from freshwater to the estuary, to the time they return as adults to the home river. Further it is important to get information on the temperature regime during the first and second year in the sea, temperature preferences at different times of the year and by using information on sea surface temperatures (SST) from satellites it may be possible to map migratory routes and the geographic distribution of salmon in the sea.
Knowledge on migratory routes and feeding areas of salmon allows scientists to monitor closely environmental changes in particular areas of the Atlantic Ocean. These can be used to explain changes in growth and mortality rates of the species and to build models that predict changes in population size. Information from the tags also yield information on vertical distribution of salmon in relation to temperature and diurnal temperature/growth relationships that can be very valuable in assessing the potential of salmon being intercepted by pelagic fisheries.
The first DST micro tags are being delivered.
Here you can read more about the DST micro fish tag.
Star-Oddi is pleased to announce a new feature in the DST series, called DST logic. The new feature allows scientists to choose a depth limit when the DST logger shall start recording. This means, while above the predetermined depth, the logger is not storing the measurements, saving the memory and battery life. As soon as the logger gets below certain depth it is triggered to begin storing the measurements in its memory. Therefore, the whole memory can be used for measurements within the specified depth range, and not wasted on recordings above surface.
This is particularly useful for scientist conducting research on fishing gear, where the logger spends considerable time on the deck, or on marine animals that spend much of their time above water as on seals and seabirds to name a few.
This feature is available for DST centi (depth-temp) series and DST CTD (depth-temp-salinity).
Visit DST centi temperature and depth logger site or the DST CTD site for further information about the loggers.
The effects of tagging large salmon smolt with DST micro tags have now been investigated in a rearing experiment. Scientists at the Institute of Freshwater Fisheries in Iceland conducted the experiment in November 2004 through February 2005. Dummy DST micro tags were used but they are identical to real DST micro tags in size and weight, but without electronics inside.
The aim of the study was to find out the influence of tagging with DST micro tags inserted into the fish body cavity. The outer shell of the tags was made of ceramic, but for comparison one group was tagged with plastic tags. 
The tags were placed into the body cavity with a surgery and after recovery the fish were reared in tank for about 3 months. The fish were individually tagged with serial coded micro tags, which make it possible to register the influences of the tagging on each individual.
The mortality of the experimental fish indicates that the antibiotic and vitamin have positive impacts on the tagged fish. This also indicates the importance of sewing the tagged fish. The results are now being analysed further and the result will be published on Star-Oddi website.
Click here to read the preliminary result!! (PDF document)
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