02122nas a2200229 4500008004100000022001400041245007300055210006900128260001600197300001000213490000700223520144400230653001701674653002601691653001501717653002201732653002201754100001701776700001801793700002701811856005401838 2020 eng d a0046-507000aSix steps towards operationalising freshwater ecoacoustic monitoring0 aSix steps towards operationalising freshwater ecoacoustic monito cFeb-01-2021 a1 - 60 v653 a

1. Applications in bioacoustics and its sister discipline ecoacoustics have increased exponentially over the last decade. However, despite knowledge about aquatic bioacoustics dating back to the times of Aristotle and a vast amount of background literature to draw upon, freshwater applications of ecoacoustics have been lagging to date.

2.In this special issue, we present nine studies that deal with underwater acoustics, plus three acoustic studies on water‐dependent birds and frogs. Topics include automatic detection of freshwater organisms by their calls, quantifying habitat change by analysing entire soundscapes, and detecting change in behaviour when organisms are exposed to noise.

3.We identify six major challenges and review progress through this special issue. Challenges include characterisation of sounds, accessibility of archived sounds as well as improving automated analysis methods. Study design considerations include characterisation analysis challenges of spatial and temporal variation. The final key challenge is the so far largely understudied link between ecological condition and underwater sound.

4.We hope that this special issue will raise awareness about underwater soundscapes as a survey tool. With a diverse array of field and analysis tools, this issue can act as a manual for future monitoring applications that will hopefully foster further advances in the field.

10aecoacoustics10aEcological Monitoring10afreshwater10apassive acoustics10aunderwater sounds1 aLinke, Simon1 aGifford, Toby1 aDesjonquères, Camille uhttps://onlinelibrary.wiley.com/toc/13652427/65/102251nas a2200313 4500008004100000245009200041210006900133520124800202653002801450653001701478653003201495653001501527100002701542700002801569700001801597700002301615700003001638700002201668700002101690700002801711700002201739700002101761700001701782700002801799700002601827700002201853700001901875856004301894 2018 eng d00aIt's time to listen: there is much to be learned from the sounds of tropical ecosystems0 aIts time to listen there is much to be learned from the sounds o3 a

Knowledge that can be gained from acoustic data collection in tropical ecosystems is low-hanging fruit. There is every reason to recordand with every day, there are fewer excuses not to do it. In recent years, the cost of acoustic recorders has decreased substantially(some can be purchased for under US$50, e.g., Hillet  al.2018) and the technology needed to store and analyze acoustic data is contin-uously improving (e.g., Corrada Bravoet  al.2017, Xieet  al.2017). Soundscape recordings provide a permanent record of a site at agiven time and contain a wealth of invaluable and irreplaceable information. Although challenges remain, failure to collect acoustic datanow in tropical ecosystems would represent a failure to future generations of tropical researchers and the citizens that benefit fromecological research. In this commentary, we (1) argue for the need to increase acoustic monitoring in tropical systems; (2) describe thetypes of research questions and conservation issues that can be addressed with passive acoustic monitoring (PAM) using both short-and long-term data in terrestrial and freshwater habitats; and (3) present an initial plan for establishing a global repository of tropical recordings.

10aconservation technology10aecoacoustics10apassive acoustic monitoring10aSoundscape1 aDeichmann, Jessica, L.1 aAcevedo-Charry, Orlando1 aBarclay, Leah1 aBurivalova, Zuzana1 aCampos-Cerqueira, Marconi1 ad'Horta, Fernando1 aGame, Edward, T.1 aGottesman, Benjamin, L.1 aHart, Patrick, J.1 aKalan, Ammie, K.1 aLinke, Simon1 aNascimento, Leandro, Do1 aPijanowski, Bryan, C.1 aStaaterman, Erica1 aAide, Mitchell uhttp://doi.wiley.com/10.1111/btp.12593