Jahn Olaf, Ganchev Todor D, Marques Marinez I, Schuchmann Karl-L
National Institute for Science and Technology in Wetlands (INAU), Science without Borders Program, Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso, Brazil.
Zoological Research Museum A. Koenig (ZFMK), Bonn, North Rhine-Westphalia, Germany.
PLoS One. 2017 Jan 13;12(1):e0169041. doi: 10.1371/journal.pone.0169041. eCollection 2017.
Computer-assisted species recognition facilitates the analysis of relevant biological information in continuous audio recordings. In the present study, we assess the suitability of this approach for determining distinct life-cycle phases of the Southern Lapwing Vanellus chilensis lampronotus based on adult vocal activity. For this purpose we use passive 14-min and 30-min soundscape recordings (n = 33 201) collected in 24/7 mode between November 2012 and October 2013 in Brazil's Pantanal wetlands. Time-stamped detections of V. chilensis call events (n = 62 292) were obtained with a species-specific sound recognizer. We demonstrate that the breeding season fell in a three-month period from mid-May to early August 2013, between the end of the flood cycle and the height of the dry season. Several phases of the lapwing's life history were identified with presumed error margins of a few days: pre-breeding, territory establishment and egg-laying, incubation, hatching, parental defense of chicks, and post-breeding. Diurnal time budgets confirm high acoustic activity levels during midday hours in June and July, indicative of adults defending young. By August, activity patterns had reverted to nonbreeding mode, with peaks around dawn and dusk and low call frequency during midday heat. We assess the current technological limitations of the V. chilensis recognizer through a comprehensive performance assessment and scrutinize the usefulness of automated acoustic recognizers in studies on the distribution pattern, ecology, life history, and conservation status of sound-producing animal species.
计算机辅助物种识别有助于分析连续音频记录中的相关生物信息。在本研究中，我们评估了这种方法基于成年南方麦鸡（Vanellus chilensis lampronotus）的发声活动来确定其不同生命周期阶段的适用性。为此，我们使用了在2012年11月至2013年10月期间以全天候模式在巴西潘塔纳尔湿地收集的14分钟和30分钟的被动声景记录（n = 33201）。通过特定物种的声音识别器获得了带时间戳的南方麦鸡鸣叫事件检测结果（n = 62292）。我们证明繁殖季节在2013年5月中旬至8月初的三个月期间，处于洪水周期结束和旱季高峰期之间。确定了麦鸡生活史的几个阶段，推测误差范围为几天：繁殖前、领地建立和产卵、孵化、育雏、雏鸟的亲代防御以及繁殖后。昼夜时间分配证实了6月和7月中午时段的高声学活动水平，表明成年麦鸡在保护幼雏。到8月，活动模式已恢复到非繁殖模式，黎明和黄昏前后出现高峰，中午炎热时段鸣叫频率较低。我们通过全面的性能评估评估了南方麦鸡识别器当前的技术局限性，并审视了自动声学识别器在研究发声动物物种的分布模式、生态学、生活史和保护状况方面的有用性。
