Todd Nicole Rose Eileen, Kavanagh Ailbhe Sarah, Rogan Emer, Jessopp Mark John
MaREI Centre Environmental Research Institute, University College Cork Cork Ireland.
School of Biological, Earth & Environmental Sciences (BEES) University College Cork Cork Ireland.
Ecol Evol. 2023 Jun 9;13(6):e10186. doi: 10.1002/ece3.10186. eCollection 2023 Jun.
Passive acoustic monitoring (PAM) is a cost-effective method for monitoring cetacean populations compared with techniques such as aerial and ship-based surveys. The Cetacean POrpoise Detector (C-POD) has become an integral tool in monitoring programs globally for over a decade, providing standardized metrics of occurrence that can be compared across time and space. However, the phasing out of C-PODs following the development of the new Full waveform capture POD (F-POD) with increased sensitivity, improved train detection, and reduced false-positive rates represents an important methodological change in data collection, particularly when being introduced into existing monitoring programs. Here, we compare the performance of the C-POD with that of its successor, the F-POD, co-deployed in a field setting for 15 months, to monitor harbor porpoise (). While similar temporal trends in detections were found for both devices, the C-POD detected only 58% of the detection-positive minutes (DPM), recorded by the F-POD. Differences in detection rates were not consistent through time making it difficult to apply a correction factor or directly compare results obtained from the two PODs. Generalized additive models (GAMs) were used to test whether these differences in detection rates would have an effect on analyses of temporal patterns and environmental drivers of occurrence. No differences were found in seasonal patterns or the environmental correlates of porpoise occurrence (month, diel period, temperature, environmental noise, and tide). However, the C-POD failed to detect sufficient foraging rates to identify temporal patterns in foraging behavior, which were shown by the F-POD. Our results suggest that the switch to F-PODs will have little effect on determining broad-scale seasonal patterns of occurrence but may improve our understanding of fine-scale behaviors such as foraging. We highlight how care must be taken interpreting F-POD results as indicative of increased occurrence when used in time-series analysis.
与空中和船舶调查等技术相比，被动声学监测（PAM）是一种监测鲸类种群的经济有效方法。十多年来，鲸类鼠海豚探测器（C-POD）已成为全球监测计划中不可或缺的工具，提供可在时间和空间上进行比较的标准化出现指标。然而，随着新型全波形捕获POD（F-POD）的开发，其灵敏度提高、列车检测得到改善且误报率降低，C-POD逐步淘汰，这代表了数据收集方面的一项重要方法变革，特别是在引入现有监测计划时。在此，我们将C-POD与其继任者F-POD的性能进行比较，二者在野外环境中共部署了15个月，以监测港湾鼠海豚。虽然两种设备检测到的时间趋势相似，但C-POD仅检测到F-POD记录的检测阳性分钟数（DPM）的58%。检测率的差异在不同时间并不一致，因此难以应用校正因子或直接比较从两个POD获得的结果。广义相加模型（GAMs）用于测试这些检测率差异是否会对时间模式分析和出现的环境驱动因素产生影响。在季节性模式或鼠海豚出现的环境相关性（月份、昼夜时段、温度、环境噪声和潮汐）方面未发现差异。然而，C-POD未能检测到足够的觅食率以识别觅食行为的时间模式，而F-POD则显示出了这种模式。我们的结果表明，改用F-POD对确定大范围的季节性出现模式影响不大，但可能会改善我们对觅食等精细行为的理解。我们强调，在时间序列分析中使用F-POD结果来指示出现增加时，必须谨慎解释。
