Issue_20March07

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NEWSLETTER ISSUE 1/07 March 2007


Increased memory size for temp-depth DST logger!

Star-Oddi introduces DST milli-F, a small temperature and depth recording Data Storage Tag (DST) with large memory size. The new type has a FLASH memory, where number of stored measurements is total 700,000 measurements (or 350,000 meaqsurements of paired temp-depth). Resolution is 12 bit, or 0.032°C and 0.03% of selected depth range.

Using FLASH memory instead of EEPROM memory in data tags has advantages and disadvantages.
- Advantage: Larger memory capacity.
- Disadvantage: Shorter battery life, because of higher current consumption.

The DST milli-F has a battery lifetime of two years, but this can vary with sampling interval used. The user sets the sampling interval when starting the logger. The temp-depth logging tag can be reused multiple times for shorter recording periods, as long as the battery lasts. When not measuring, the tag is kept in sleep mode, saving the battery life.

Tests of the DST milli-F have been completed at Star-Oddi development department, and is being transferred to production. Please contact Star-Oddi to place an an order or request for quotation.

Star-Oddi will continue delivering standard DST milli with low power non-volatile EEPROM memory, as before. 



Lobster tagging with DST micro 

In 2006 the Ogasawara Fishery Institute performed lobster tagging, using DST micro, recording depth and temperature with date-time.

Ogasawara Islands are located far southern Tokyo Prefecture.  Among many kinds of fish offshore Ogasawara, endemic species of lobster (academic name, Panulirus brunneiflagellum ) are habitant, as one of the most important resource.

The lobster growns up to weigh over 3kg, and its length can get over 40 cm.

On the mature pregnant female berry, a particular feature of black coloring, pigment spot,  is observed. The hypothesis is that the color depth is related with water temperature, as the tendency has been seen during a long year actual fishing.

In order to prove the hypothesis, tagging with DST micro was scheduled. Before sea trial a laboratory test was done. During the laboratory test some of DST micros  were  half eaten or bitten off by other lobsters. It is likely that the white color of the tag housing attracted the lobsters, for it is well known that the lobster is fond of eating a white shellfish, a kind of oyster.

Cod tagging project at UNH

The goal of the project is to study the activity and fine scale distribution of spawning cod in the western Gulf of Maine (Ipswich Bay) using a combination of data storage tags (DSTs) and acoustic telemetry.

Between April 21st and May 17th, 2006, two hundred cod were captured on the spawning grounds and externally tagged with DST milli from Star Oddi.  Thirty of the same fish also had an acoustic transmitter surgically implanted.  The DSTs were programmed to record both water temperature and depth of each fish at 12-minute intervals for approximately six months, and each was imprinted with information on how to report the recapture of a DST-tagged fish. Fishermen have returned twenty-one DSTs so far (10.5% recapture rate). Recapture locations have ranged from Platts Bank (90 km to the northeast of the tagging location) to Stellwagen Bank (80km to the southeast).

Data analyses are just beginning, but preliminary results suggests that spawning cod in Ipswich Bay occupy relatively uniform and consistent depths in May and early June, sometimes punctuated by brief ascents to much shallower depths, which may reflect spawning events.  There is typically a dramatic shift to deeper depths in mid-June, showing that individuals have moved out of the study area.  This depth change coincides with the initiation of a wide range of vertical movement in the water column, indicating a change in behavior as well as location. Read the full article here.

Monitoring fishing gear!  

With increased selection of sensor, the DST loggers have become popular for use on various fishing gear, studying its behavior.  Improve fishing efficiency by collecting data as depth, temperature, salinity, pitch & roll and compass. The DSTs are available with a protective housing.




Click here
and have a closer look at our products on our website.

Temperature Data Loggers - suitable for various projects!

Temperature Recorder

Starmon mini Underwater Temperature Recorders: Accurate, reliable and robust temperature recorders with large memory size and long battery life for environmental studies.

Click here for more information


Visit our website and view other products and scientific papers related to your field. If you would like to receive a price quote, know more about the company or the products please contact us.



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Star-Oddi | Vatnagardar 14 | 104 Reykjavik | Iceland | Tel: +354 533 6060 | Fax: +354 533 6069 |

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