Smith Bethany R, Bru Elisabeth, Faur Mihaela, Kershenbaum Arik
School of Animal, Rural and Environmental Sciences Nottingham Trent University Southwell UK.
Institute of Zoology Zoological Society of London London UK.
Ecol Evol. 2025 Mar 4;15(3):e71041. doi: 10.1002/ece3.71041. eCollection 2025 Mar.
Golden jackals () have rapidly expanded their range across Europe, raising ecological and socioeconomic concerns. As a highly vocal species, jackals can be monitored using howl surveys or passive acoustic monitoring (PAM) to estimate population sizes and habitat preferences. A recent advancement in PAM is acoustic localisation, which estimates the source of sounds by measuring the time differences of their arrival at multiple synchronised recorders. This technique can improve the accuracy of population and density estimates by more precisely calculating distances between vocalising animals and recorders. However, GPS-synchronised acoustic recorders are costly, which limits their broader use. In this study, we tested the efficacy of a low-cost recorder, the CARACAL, for acoustic localisation of golden jackals. We deployed 10 CARACALs over a 10 km area of the Lunca Mureşului Natural Park, Romania, for seven nights. Alongside passively recording jackal howls, we also conducted howl surveys. We recorded jackal howls every night of the survey and successfully localised 27 jackal and 16 human howls, with human howls localised to within an average of 41 m of their actual location. The average distance between the recorders and estimated positions of vocalising jackals was just under 1 km, with howls detected from as far as 2.5 km away. However, some jackal howls were not detected clearly, or at all, on active recorders that were as little as 0.9 km away. Based on these results, we recommend a conservative spacing of 0.8-1 km between recorders in future deployments, though this will depend on local environmental conditions. Overall, this study highlights acoustic localisation as a valuable tool for improving monitoring efforts and gathering more detailed data on jackal ecology. This information could significantly contribute to understanding their expanding range across Europe while informing the development of effective monitoring and management strategies for golden jackals.
金豺（）在欧洲迅速扩大了其活动范围，引发了生态和社会经济方面的担忧。作为一种发声频繁的物种，可以通过嚎叫调查或被动声学监测（PAM）来监测金豺，以估计其种群规模和栖息地偏好。PAM的一项最新进展是声学定位，它通过测量声音到达多个同步记录仪的时间差来估计声源。这项技术可以通过更精确地计算发声动物与记录仪之间的距离，提高种群和密度估计的准确性。然而，GPS同步声学记录仪成本高昂，这限制了它们的更广泛应用。在本研究中，我们测试了一种低成本记录仪CARACAL对金豺进行声学定位的效果。我们在罗马尼亚伦卡穆列舒卢伊自然公园10公里的区域内部署了10台CARACAL，持续了七个晚上。在被动记录金豺嚎叫的同时，我们还进行了嚎叫调查。在调查的每个晚上我们都记录到了金豺的嚎叫，并成功定位了27次金豺嚎叫和16次人类嚎叫，人类嚎叫的定位平均距离其实际位置在41米以内。记录仪与发声金豺估计位置之间的平均距离略低于1公里，最远能检测到2.5公里外的嚎叫。然而，在距离仅0.9公里的有源记录仪上，一些金豺嚎叫没有被清晰检测到，甚至根本没有检测到。基于这些结果，我们建议在未来的部署中，记录仪之间保守的间距为0.8至1公里，不过这将取决于当地的环境条件。总体而言，本研究强调了声学定位是一种有价值的工具，可用于改进监测工作并收集有关金豺生态的更详细数据。这些信息对于理解它们在欧洲不断扩大的活动范围具有重要意义，同时也为制定有效的金豺监测和管理策略提供依据。
