Barbara Promberger-Fuerpass, Christoph Promberger, Munich Wildlife Society, Linderhof 2, D-82488 Ettal, Germany

Wolves are known to use howling and scent marking to advertise a pack's territory. However, different hypothesis exist about the spatial distribution of both, scent marks and the location of howling sessions, within the home range. In this study we tried to find out whether the intensity of territorial behavior shown by wolves is related to the importance of certain areas for the territorial pack.

Four individuals (3 females, 1 male) from different packs were radio-collared and monitored for up to three years. To define four zones of ascending importance in each territory we used the Kernel analysis to highlight areas of concentrated activity. Since for all packs 40% of the locations were on less than 10% of the total range, the area within the 40% Isoline was determined as the center of the territory. During winter 1997/98 we mapped four different types of scent-marks (RLU, SQU, Scats, and Scratching) along 86 km of snow-tracks. Howling was simulated to measure the response rate and the reaction (leaving, staying, approaching) of radio-marked wolves to potential intruders.

There was no significant difference in the distribution of scent-marks. Wolves in neither pack used to mark the periphery more than any other place in the territory. However, along roads or trails we found a significantly higher deposition rate (5.4 scents/km; n=36) than along tracks in the forest (2.0 scents/km; n=19; p<0,058).

All together, 26 % of the howling experiments were answered (n=174). While the wolves rarely responded in the first two months after the young were born, they answered almost 50 % of the simulations in the period from July to October. Compared to other locations, response rates were always higher on rendezvous-sites (58% vs. 19,6%; p<0,001), and the probability of getting an answer increased with the distance between the pack and the border of the territory (log. Regression; p=0,05, n=174). Was the 'intruder' too close (within 300 m) to the radio-collared wolves, the response rate was lower (12,9% vs. 31,1%; p<0,05). Instead of answering, the wolves tended to approach. Whereas scent marks were distributed evenly, response rate to simulated howling was significantly higher in the center of the territory.