The golden jackal (Canis aureus) is a species that has arisen more often in the recent years in Slovenia and is also expanding outside its known habitat to new areas around Europe. One of the methods of monitoring the population of the jackal is provoking the sound of the jackals by playing a recording of the jackal howling (i.e. the acoustic method). The research assesses some of the influences on the detection of the territorial groups’ responses in the Republic of Slovenia and in the Republic of Croatia. It also tries to evaluate the influence of the season, diurnal activity, the distance between the responsive jackals and the listeners, vegetation, habituation of the jackals on the past provoking and the characteristics of recordings on our detection of the sounds of the territorial groups, which was poorly researched until now. Within our work with the field colleagues, we surveyed approximately 86 km2 of area in the Bela krajina region, 33 km2 of surface in the Ljubljansko barje regional park and 135 km2 at Lonjsko polje in Croatia, with several repetitions of surveys in the Slovene part of the researched area. Our work tries to point to certain improvements of the basic method and propose some aspects for the future researches in the field of acoustic characteristics of this species. The results confirm the suppositions on the territorial function of the response and its dynamics considering the season, the use of the recording and the frequency of plays. Some influences of the vegetation on our ability to detect the response was also studied, the error of human assessment of the distance (and direction) was evaluated and the guidelines for future use of this method were proposed as well. Where it is possible and required, we propose a technologically perfected solution for detection with recorders or the so called passive acoustic method upgraded with analyses of the acoustic spectrograms for more detailed studies.
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