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Methods and goals Until the beginning of this study in 1995 the movements of wild mammals in Germany were exclusively investigated terrestrially using radio
telemetry or in exceptional cases from a plane.
Worldwide, however, the spatial orientation, choice of habitat, and behaviour of many animal species was already being investigated with the Argos Satellite System.
The Argos System is particularly suited to locating far ranging animal species, since the localization need not be more accurate than 100 m. In Germany satellite telemetry had only been used for bird
species at that time, for example, BERTHOLD et al. (1992) and KAATZ (1995) investigated the flight behaviour of storks using the Argos System.
This pilot project should provide the first test of whether the technically involved telemetry using the Global Positioning System (GPS) is practically applicable to wild
animal research (for our purposes the lack of precision in localization of the Argos System was too great). In addition the localization of one female and two male animals in the Harz were to be ascertained at
regular intervals using GPS collars, and the data transmitted via the experimatal satellilte TUBSAT-A to the ground station in Berlin.
Fig. 1: TUBSAT-A (=Technical University Berlin Satellite)
The TUBSAT-A was constructed by the working group of Prof. U. Renner at the TU Berlin and
measures only 38 x 38 x 38 cm in size with a weight of 35 kg. In 1991 together with the Ariane V44 it was put into orbit and synchronized with the sun. It was under observation from the
ground station at the TU Berlin, specifically at the Institute for Air and Space Flight where the data were also received and transformed. Data transmission occurred at the frequency of
143,075 Mhz. For one orbit around the earth the TUBSAT-A needs 100 minutes. In relation to Europe this results in two to three usable overflights, one at noon between 11.00 and 14.00
and one in the evening between 21.00 andmidnight, which successfully transmit data (all data according to RENNER, 1991).
This project is a pilot project particularly, because according to our knowledge, it was the first
telemetric investigation using GPS on wild animals in Europe. We wanted to know whether the GPS collars provide usable position coordinates of the red deer studied, even under the
difficult conditions found in the Harz, and whether these data could be transferred smoothly via TUBSAT-A to the ground station. The longevity of the batteries as well as the
functionability of the GPS collars also had to be tested.
The study was conducted in the Westharz. During three winter feedings in the evenings in
February/March 1995 two adult male red deer (Nr. 1 and Nr. 2) and a two year old female red deer (Nr. 3) were immobilized with a tranquilizing gun using injection projectiles of the system
TELEINJECT and provided with GPS collars.
The investigations were conducted in collaboration with Dr H. Woelfel from the Institute of
Wildlife Biology and Hunting Science at the University of Goettingen and R. Schulte from the Institute of Air and Space Flightat the TU Berlin (now VECTRONIC Aerospace).
Results The prior investigations resulted in an average error in localization of 100 m (n =52) using GPS
collars. A total of 373 valid localizations were obtained for the three investigated animals, of which 298 were from animal Nr. 3, a juvenile female red deer (Fig. 3).
Neither of the male red deer roamed very far; Nr. 1 used the area surrounding the winter
feeding area as his home territory from April until June 1995, Nr. 2 the same area from February until May 1995. The female red deer Nr. 3 only strayed in the area around its winter
feeding place from March 24 until April 23, 1995, and then moved to an area 8 km northwest where it stayed until August.
Fig. 3: Localization points of 1 female and 2 male red deer in the Harz, GPS Pilot Study 1995
Telemetry using GPS collars is shown to be an applicable method to investigate the spatial and
temporal behaviour of red deer in difficult terrain as the determination of the position coordinates and the transmission of data via TUBSAT-A were successful. The design and
functional life of the GPS collars should be improved for future studies.
The investigations were financed by the German Agency for Space Flight (DARA)and from
hunting research funds of the Ministries of Nutrition, Agriculture, and Forestry of Lower Saxony and Saxony-Anhalt.
Reference Berthold P., Nowak E., Querner U., 1992: Satellite telemetry for white storks (Ciconia ciconia) during migration, a pilot study. J. Orn., 133 (Heft 2):155-163.
Kaatz M., 1995: Revision, evaluation, and documentation of aerial and satellite data on the migratory behaviour of white storks. Dipl. Thesis, Institute for Geodesy and Geoinformatics,
University of Rostock. Renner U., 1991: TUBSAT-A, an experimental satellite of the TU Berlin. Z. Flugwiss Weltraumforsch. 15: 349-357.
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