Crunchant Anne-Sophie, Stewart Fiona A, Piel Alex K
School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom.
Department of Anthropology, University College London, London, United Kingdom.
PeerJ. 2021 Oct 19;9:e12326. doi: 10.7717/peerj.12326. eCollection 2021.
Patterns of vocal communication have implications for species conservation: a change in calling behaviour can, for instance, reflect a disturbed habitat. More importantly, call rate is a parameter that allows conservation planners to convert call density into animal density, when detecting calls with a passive acoustic monitoring system (PAM).
We investigated chimpanzee () call rate during the late dry season in the Issa Valley, western Tanzania by conducting focal follows. We examined the socio-ecological factors that influence call production rate of savanna woodland chimpanzees.
We found that sex, proportion of time spent in a vegetation type, proportion of time spent travelling, time of the day, party size and swollen parous female presence had a significant effect on the call rate. Call rate differed among the different demographic classes with subadult and adult males vocalising twice as often as the subadult and adult females and three times as often as the juveniles.
The use of PAM and recent statistical developments to estimate animal density is promising but relies on our knowing individual call rate, often not available for many species. With the improvement in automatic call detection, we anticipate that PAM will increasingly be broadly applied to primates but also across taxa, for conservation.
声音交流模式对物种保护具有重要意义：例如，叫声行为的变化可能反映栖息地受到干扰。更重要的是，在使用被动声学监测系统（PAM）检测叫声时，叫声频率是一个参数，它能让保护规划者将叫声密度转换为动物密度。
我们通过进行焦点跟踪，研究了坦桑尼亚西部伊萨山谷旱季后期黑猩猩的叫声频率。我们考察了影响稀树草原林地黑猩猩叫声产生频率的社会生态因素。
我们发现，性别、在某种植被类型中花费的时间比例、旅行时间比例、一天中的时间、群体规模以及怀有身孕的雌性的存在对叫声频率有显著影响。不同人口统计学类别之间的叫声频率存在差异，亚成年和成年雄性的叫声频率是亚成年和成年雌性的两倍，是幼年黑猩猩的三倍。
使用PAM以及近期的统计进展来估计动物密度很有前景，但这依赖于我们了解个体叫声频率，而许多物种往往无法获得这一信息。随着自动叫声检测技术的改进，我们预计PAM将越来越广泛地应用于灵长类动物，也会跨分类群应用于保护工作。
