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Study 2004
Introduction
Fig. 1: Location of the investigation area in Germany (red symbol)
The GPS receivers are programmed to take fixings every 2-4 hours and to send the data by SMS immediately after 7 fixings are taken via the mobile phone system directly to our groundstation at the office. The animals were caught in a corral and fitted with GPS-GSM collars (figure 2 and 3).
Three of the collars were already used last year and equipped with new batteries. All collars are state of the art:
If a collar is out of GSM coverage the GPS fix data will be immediately transmitted when GSM coverage is available. This is the most secure option to get the maximum of GPS data via GSM network. Tab. 1: Data of the collared red deer, 2004
Fig. 4: Location points of 6 red deer (legend: age in bracket; n=8678 fixes) connected in chronological order, after
leaving the winter enclosure, May 13 - December 1, 2004
Study 2003
The GPS receivers are programmed to take fixings every 2-4 hours and to send the data by SMS immediately after 7 fixings are taken via the mobile phone system directly to our groundstation at the office. The animals were caught in a corral and fitted with GPS-GSM collars (figure 2 and 3). Tab. 1: Data of the collared red deer, 2003
Fig. 4: Location points of 3 male red deer connected in chronological order, after leaving the winter enclosure, May 13 - October 6, 2003
Fig. 5: Location points of 3 female red deer connected in chronological order, after leaving the winter enclosure, May 13 - October 6, 2003 (n= 959, 1442 and 1229)
The activity of the tracked red deer has been monitored by a two axis activity logger. By this, the acceleration of the collar will be estimated 6-8 times every second and the overall mean value has been stored every 5 minutes. The complete GPS data sets and the activity and temperature data sets from the tracking period 2003 have been stored on board of the GPS GSM collar and were outried by computer via Link Manager. The activity of hint 452 are shown in figure 6.
Fig. 6: Activity data of female 452 in x- and y direction (blue and green symbols) and temperature data (red line), April 30 2003 to March 24, 2004
Study 2002 Investigations on the use of habitat of red deer in the Bavarian forest are part of a cooperative pilot project between the Management of the Bavarian Forest National Park and Environmental Studies. The GPS collars are constructed by Vectronic Aerospace, Berlin. The company has financed a part of the project costs. The Project
Fig. 2: Location points of 3 red deer connected in chronological order, after leaving the winter enclosure, May 8, 2002 - January 4, 2003 In August the female red deer and the stag spent their time in higher regions, probably because of the
disturbance by mushroom seekers in the lower areas. On September 7, the stag moved across the border to the
Czech Republic, expanding his home range. From September 24 to October 23 no data was transmitted. Probably
the animal lived in an area without GSM coverage. Since October 23 the data arrived as usual. The stag moved back to the border. Fig. 3: Location points of the 3 red deer from December 1, 2002 - January 4, 2003 In the last two weeks of September the female red deer moved down from the higher mountain areas and stayed in the first weeks of October in or nearby the winter enclosure. Whereas the young stag moved at this time into the higher mountain regions and expands his home range into Czech territory, travelled 9 km to the east, visited the winter enclosure and travelled back to the higher mountain regions. At the time the female red deer are dwelling in the winter-enclosure with 65 others, the two stags are still moving in higher mountain regions, close to the border of the Czech Republic. This is unusual behaviour, because normally red deer pass the winter in the winter-enclosure or stays in the lower foothills. But this winter, until the first week of January, the mountains were nearly free of snow and obviously food was still available.
Whereas the collar of the female red deer has a good efficiency (88%), the data transmission of the stag’s collars is less (57% and 64%). It depends on the bad GSM coverage in the border area of the Czech Republic, where the stags spend a lot of time in the higher mountain regions.
In April 2001 5 female red deer from two different winter enclosures in the Bavarian Forest National Park were outfitted with GPS-Plus collars. At present one collar has been retrieved by recapturing one of the animals. The collar contained recordings of 6500 localizations from April 2001 to March 2002, whereby positions were recordedhourly. The migratory paths of the animal are shown in Fig. 5.
Fig. 5: Location points of a female red deer connected in chronological order, The 3 year old female red deer showed a conspicuous migratory pattern. It only wandered to the periphery of its range from the central area to which it quickly returned. Longer treks or excursions over several days outside of its home range did not occur.The animal was very homebound in choosing its winter quarters. It spent the winter in the same winter enclosure as the previous year. The female red deer first remained in the vicinity of this enclosure upon its release on May 15, 2001. Later it moved to an area 5 km to the north. The animal often moved back and forth through a small corridor between these two ranges. The upper range encompassed an area of 843 ha, the lower an area of 900 ha (calculated by the convex polygon method, see also first introduction to our work with satellite telemetry).
More information about the project After the establishment of the Bavarian Forest as a national park attempts were made to develop solutions for the management of red deer in such a setting. On the one hand the high population density of the red deer was reduced and on the other unfenced feeding stations were removed in favour of 3 enclosed ones for the winter (“winter enclosures”), where the animals could overwinter. This management concept greatly helped reduce browsing and stripping damage to trees and saplings. This winter enclosure management method has been proved successful since the 1970’ and `80`. An investigation conducted in 1984 showed that extensive areas in the Bavarian Forest National Park were not used by the red deer. The majority of the red deer in this park overwintered in the enclosures and had their summer ranges on Czech territory between the national border and the farther border fence. In the past few years several changes have occurred to influence the habitat and behaviour of the red deer:
Fig. 4: View from the village of St. Oswald towards the Rachel.Behind the mountain range lies the National Park Sumava in the Czech Republic. The red deer management system effectively practiced for years must now be adapted to the changed conditions.For this purpose, an exact analysis of the above mentioned changes and an evaluation of alternative solutions is necessary. The present investigation is the first step in obtaining basic data on the actual use of habitat by red deer in the Bavarian Forest National Park and in the Sumava National Park.The following questions must be answered:
Author's e-mail address: Dr Marco Heurich, Dr Uli Fielitz,
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