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Tracking storks with satellite transmitters
  • Who can we track?
  • Two new taggs
  • How does the transmitter work?

Who can we track?

At this moment we can track 3 White storks with a satellite transmitter. One male Pumba and two females, Germaine and anonymus. You can look for information on these birds by clicking on the left column, you will find their recent location and the diary of the birds.

Pumba and Germaine were breeding in Mechelen, Belgium in Animal Parc Planckendael.

A fourth Stork Rene (a female) is still wearing its transmitter but it is not signalling anymore.


Two new taggs

In August 2006 we can tagg two new storks with a transmitter. We use 25 gram satellite transmitters with solar panle and manifactured by North Star (www.northstarst.com).

How does the transmitter work?

The storks are equipped with 25 or 35 g solar powered satellite transmitters. The transmitter is placed on the back of the stork with nylon and teflon  ropes. The transmitters are PTT-100s constructed by Microwave Telemetry (http://www.microwavetelemetry.com) and North Star (http://www.northstarst.com).

The biggest advantage of using satellite transmitters is that data on the behaviour and the migration route can be collected for individual birds. From a ringed individual you will only get information about the time and place where the bird is ringed and where it is recaptured or found. Because storks are very conspicuous birds there is a recovery rate of 20 to 25 %, which is high for a bird. From a tagged stork can we collect hundreds to thousands of locations and follow it from day to day for an important part of its life. From a German stork we collected thanks to the satellite in 10 months about 1.400 locations (data Vogelwarte Radolfzell). This is of course a enormous amount of information.

Every 50 seconds is the transmitter sending a signal that can be picked up by a satellite. These are NOAA-satellites that follow a polar orbit and can receive and store all information. When the satellites are in contact with the ground station they will transmit all the data. The data are then analysed in the ground station in Toulouse, France. The localisation of the stork is measured using the Doppler-effect, by comparing the received frequencies several times with the standard frequency.

Every day the transmitter can give up to 8 locations.

The locations and information of the sensors in the transmitter are send to us as follows :

14559 Date : 30.07.99 19:30:38 LC : 1  IQ : 50
Lat1 : 51.003N Lon1 : 4.483 E  Lat2 : 45.733 N Lon2 : 23.114 W
Nb mes : 006 Nb mes >-120 dB : 000  Best level : -126 dB
Pass duration : 379s  NOPC : 3
Calcul freq : 401 653408.1 Hz  Altitude : 80 m
00 06 61 01

First line : number of the transmitter, date, hour (GMT), accuracy of the location  (LC), quality of the receipt (IQ)
Second line : two locations that are calculated using Doppler effect, in this example the first location is the right one (Mechelen, Planckendael)
Third line : number of received signals, number of signals > –120dB and the best reception in dB.
Fourth line : contact period between transmitter and satellite, number of tests (how longer the contact is, the better the locations can be).
Fifth line : calculated frequency of the transmitter, altitude.
Sixth line : sensor data : temperature (coded), battery level, counter, activity counter (0 to 255)

We use the locations provided by the satellite to produce the maps with the migratory movements of the storks. With these coordinats and a GPS (Global Positioning System) is it possible to go to a certain place and observe the bird.