MARE - Marine and Environmental Sciences Centre / ARNET - Aquatic Research Network, ISPA-Instituto Universitário, Lisbon, Portugal; Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.
Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal; IMBRSEA Master Programme, Ghent University, Ghent, Belgium.
Mar Environ Res. 2023 Jun;188:106017. doi: 10.1016/j.marenvres.2023.106017. Epub 2023 May 4.
Invasive alien species have been rising exponentially in the last decades impacting biodiversity and ecosystem functioning. The soniferous weakfish, Cynoscion regalis, is a recent invasive sciaenid species in the Iberian Peninsula and was first reported in the Tagus estuary in 2015. There is concern about its possible impacts on native species, namely the confamiliar meagre, Argyrosomus regius, as there is overlap in their feeding regime, habitat use, and breeding behaviour. Here, we characterised the sciaenid-like sounds recently recorded in the Tagus estuary and showed that they are made by weakfish as they have similar numbers of pulses and pulse periods to the sounds made by captive breeding weakfish. We further demonstrate that breeding grunts from weakfish and the native sciaenid, recorded either in captivity or Tagus estuary, differ markedly in sound duration, number of pulses and pulse period in the two species, but overlap in their spectral features. Importantly, these differences are easily detected through visual and aural inspections of the recordings, making acoustic recognition easy even for the non-trained person. We propose that passive acoustic monitoring can be a cost-effective tool for in situ mapping of weakfish outside its natural distribution and an invaluable tool for early detection and to monitor its expansion.
在过去几十年中，入侵的外来物种呈指数级增长，对生物多样性和生态系统功能产生了影响。发声鲈 Cynoscion regalis 是伊比利亚半岛最近入侵的拟石首鱼科物种，于 2015 年首次在塔霍河口被报道。人们担心它可能对本地物种产生影响，特别是亲缘关系密切的银无须鳕 Argyrosomus regius，因为它们的摄食方式、栖息地利用和繁殖行为存在重叠。在这里，我们对塔霍河口最近记录到的拟石首鱼样声音进行了特征描述，结果表明这些声音是由发声鲈发出的，因为它们的脉冲数和脉冲周期与人工养殖的发声鲈发出的声音相似。我们进一步证明，无论是在人工养殖还是在塔霍河口记录的来自发声鲈和本地拟石首鱼的繁殖呼噜声，在声音持续时间、脉冲数和脉冲周期方面在两个物种之间有明显的差异，但在它们的频谱特征上有重叠。重要的是，这些差异可以通过对录音的视觉和听觉检查轻松检测到，即使是非专业人员也很容易进行声学识别。我们提出，被动声学监测可以成为在其自然分布范围之外对发声鲈进行原位测绘的一种具有成本效益的工具，也是早期检测和监测其扩张的宝贵工具。
