Paisaje acústico de arrecifes de coral costeros protegidos y desprotegidos del Atlántico tropical

Behavioural patterns and distributions of crustaceans, fish and mammals can be inferred from acoustic recordings of the extremely noisy marine acoustic environment. In this study, we determined the soundscape of protected and non-protected marine areas between January and April 2016. Sonobuoy (a device for sound monitoring) recordings began at sunset and lasted approximately 12 hours per day. The results show a complex soundscape dominated by biological sounds produced by crustaceans and fish. Six fish chorus-dominant frequencies between 200 and 1000 Hz occurred at a similar time each day, except for chorus I. The choruses consisted of high-energy callings after the last reef line within the protected area. However, fish choruses showed low energy levels in unprotected areas. The results show the importance of protected areas for fish populations and the usefulness of passive acoustics to monitor biodiversity of sounds of commercial fish in Brazilian tropical costal reefs.Los patrones de comportamiento y la distribución de crustáceos, peces y mamíferos pueden inferirse a partir de grabaciones acústicas del ambiente acústico marino extremadamente ruidoso. En este estudio, determinamos el paisaje sonoro de áreas marinas protegidas (AMP) y no protegidas entre enero y abril de 2016. Las grabaciones de “sonoboyas” (un dispositivo para monitoreo de sonido) comenzaron al atardecer y duraron aproximadamente 12 horas por día. Los resultados muestran un paisaje acústico complejo dominado por sonidos biológicos producidos por crustáceos y peces. Se encontraron seis frecuencias dominantes de coros de peces entre 200 y 1000 Hz, encontrados a la misma hora todos los días, excepto el coro I. Los coros consistían en llamadas de alta energía después de la última línea de arrecife dentro del área protegida. Sin embargo, los coros de pescado presentaron niveles de energía bajos en áreas desprotegidas. Los resultados muestran la importancia de las áreas protegidas para las poblaciones de peces y la utilidad de la acústica pasiva para monitorear la biodiversidad de los sonidos de los peces comerciales en los arrecifes costeros tropicales brasileños

Listening forward: approaching marine biodiversity assessments using acoustic methods

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Mooney, T. A., Di Iorio, L., Lammers, M., Lin, T., Nedelec, S. L., Parsons, M., Radford, C., Urban, E., & Stanley, J. Listening forward: approaching marine biodiversity assessments using acoustic methods. Royal Society Open Science, 7(8), (2020): 201287, doi:10.1098/rsos.201287.Ecosystems and the communities they support are changing at alarmingly rapid rates. Tracking species diversity is vital to managing these stressed habitats. Yet, quantifying and monitoring biodiversity is often challenging, especially in ocean habitats. Given that many animals make sounds, these cues travel efficiently under water, and emerging technologies are increasingly cost-effective, passive acoustics (a long-standing ocean observation method) is now a potential means of quantifying and monitoring marine biodiversity. Properly applying acoustics for biodiversity assessments is vital. Our goal here is to provide a timely consideration of emerging methods using passive acoustics to measure marine biodiversity. We provide a summary of the brief history of using passive acoustics to assess marine biodiversity and community structure, a critical assessment of the challenges faced, and outline recommended practices and considerations for acoustic biodiversity measurements. We focused on temperate and tropical seas, where much of the acoustic biodiversity work has been conducted. Overall, we suggest a cautious approach to applying current acoustic indices to assess marine biodiversity. Key needs are preliminary data and sampling sufficiently to capture the patterns and variability of a habitat. Yet with new analytical tools including source separation and supervised machine learning, there is substantial promise in marine acoustic diversity assessment methods.Funding for development of this article was provided by the collaboration of the Urban Coast Institute (Monmouth University, NJ, USA), the Program for the Human Environment (The Rockefeller University, New York, USA) and the Scientific Committee on Oceanic Research. Partial support was provided to T.A.M. from the National Science Foundation grant OCE-1536782

Soundscape maps of soniferous fishes observed from a mobile glider

Most passive acoustic studies of the soundscape rely on fixed recorders, which provide good temporal resolution of variation in the soundscape, but poor spatial coverage. In contrast, a mobile recording device can show variation in the soundscape over large spatial areas. We used a Liquid Robotics SV2 wave glider fitted with a tow body with a passive acoustic recorder and hydrophone, to survey and record the soundscape of the Atlantic Ocean off North Carolina (USA). Recordings were analyzed using power spectral band (PSB) sums in frequencies associated with soniferous fish species in the families Sciaenidae (drums and croakers), Ophidiidae (cusk-eels), Batrachoididae (toadfish), Triglidae (sea robins), and Serranidae (groupers). PSB sums were plotted as the wave glider moved offshore and along the coast, came back inshore, and circled artificial and natural reefs. The soundscape in water 120 dB re 1 �Pa2: a Sciaenidae mixed-species chorus, an unknown “grunt� chorus, an unknown “buzz� chorus, and an Ophidiidae chorus. The Ophidiidae and unknown “buzz� fish choruses dominated in the range of 1600 Hz to 3200 Hz and were similar in sound pressure level (SPL) to the US Navy recordings made at Cape Lookout (136 dB in 2017 vs 131 dB in 1943). In deeper water (27 m to 30 m), we recorded Triglidae “honks�, oyster toadfish “boat whistles�, Sciaenidae “booms� and “clucks�, and grouper “growls�. We recorded a nocturnal 5600-Hz signal while the glider was passing near known live bottom reefs and artificial reefs. Vessel noise (100 Hz to 200 Hz) was part of the soundscape in shipping lanes as large cargo vessels passed by the glider. Rainfall and thunder were also part of the soundscape. The maximum SPL observed (148 dB re 1 µPa) occurred during a mixed-species Sciaenidae fish chorus near Cape Lookout that was dominated by unknown “grunt� calls. Passive acoustic monitoring from mobile platforms can be used to discover and map the locations of fish choruses, identify areas of their habitat use, and locate previously unknown locations of reefs and fish spawning areas during ocean surveys.ECU Open Access Publishing Support Fun

Southern right whale vocalisations, and the “spot” call in Australian waters: characteristics; spatial and temporal patterns; and a potential source - the southern right whale

Passive acoustic recordings collected in Australian temperate waters were used to provide the first summary of southern right whale (Eubalaena australis) vocalisations in Australia, and to document the characteristics, and temporal and spatial patterns of an as yet unattributed whale sound, referred to as the “spot” call, which is suggested to be produced by the southern right whale

Passive acoustic monitoring for assessment of natural and anthropogenic sound sources in the marine environment using automatic recognition

In the marine environment, sound can be an efficient source of information. Indeed, several marine species, including fish, use sound to navigate, select habitats, detect predators and prey, and to attract mates. Therefore, all the abiotic, biotic and manmade sounds that comprise the soundscape, have the potential to be used to assess and monitor species and marine environments. Passive acoustic monitoring (PAM) involves the use of acoustic sensors to record sound in the environment, from which relevant ecological information can be inferred. This thesis studied marine soundscapes, with special attention on fish communities, anthropogenic noise, and applied several methods to analyse acoustic recordings. Most of the focus was on the Tagus estuary, where the presence of two highly vocal species is known: the Lusitanian toadfish (Halobatrachus didactylus) and the meagre (Argyrosomus regius). Azorean and Mozambique soundscapes were also analysed. Several methods were applied to extract information and to visualize soundscape characteristics, including sound recognition systems based on hidden Markov models to recognize fish sounds and boat passages. Analysis of several types of marine environments and time scales showed several advantages and disadvantages of different methods. The use of sound pressure level on different frequency bands allowed the quantification of daily and seasonal patterns. Ecoacoustic indices appear to be cost-effective tools to monitor biodiversity in some marine environments. Using automatic recognition, vocal rhythms (diel and seasonal patterns) and vocal interactions among individuals were also characterized. Furthermore, boat noise effects on fish were studied: we encountered impacts on the audition, vocal behaviour and reproduction. Overall, we used PAM as a tool to remotely assess and monitor soundscapes, biodiversity, fish communities’ seasonal patterns, fish behaviour, species presence, and the effect of anthropogenic noise aiming to contribute for the management and conservation of marine ecosystems

Fish sounds and boat noise are prominent soundscape contributors in an urban European estuary

Passive acoustic monitoring is a valuable tool for non-intrusive monitoring of marine environments, also allowing the assessment of underwater noise that can negatively affect marine organisms. Here we provide for the first time, an assessment of noise levels and temporal soundscape patterns for a European estuary. We used several eco-acoustics methodologies to characterize the data collected over six weeks within May 2016 - July 2017 from Tagus estuary. Biophony was the major contributor dominated by fish vocalizations and the main driver for seasonal patterns. Maritime traffic was the major source of anthropogenic noise, with daily patterns monitored using 1584 Hz third-octave band level. This indicator avoided biophony and geophony, unlike other indicators proposed for the EU Marine Strategy Framework Directive. Furthermore, the frequency overlap between anthropophony and biophony demands precautionary actions and calls for further research. This study provides an assessment that will be useful for future monitoring and management strategies.Fundação para a Ciência e Tecnologia - FCTinfo:eu-repo/semantics/publishedVersio

Acoustic impact of a wave energy converter in Mediterranean shallow waters

In this study, underwater noise from a full-scale wave energy converter system (ISWEC), installed on the coast of Pantelleria Island (central Mediterranean Sea), was characterized. The noise was measured using an autonomous acoustic recorder anchored to the sea bottom 40 m from the ISWEC hull. Acoustic monitoring continued for 15 months, starting 7 months before (PRE), 2 months during (INST) and 6 months after the ISWEC installation (POST). The levels of noise, assessed with power spectrum density and octave and third-octave band sound pressure levels (BSPLs), were higher during the POST period than during the PRE period at lower frequencies up to 4 kHz and increased with wave height. During the ISWEC activation for energy production (POST_ON) in the wave height range 1–2.9 m, the BSPLs increased much more at lower frequencies up to 4 kHz (the median BSPLs at 63 Hz for the PRE, POST, and POST_ON conditions were 73, 106, and 126 dB re 1μPa, respectively). Considering the biophonies that make up the soundscape of the area, we examined the possible masking of fish choruses due to ISWEC noise and highlighted that at a distance of 1000 m, the 800 Hz peak frequency was 10 dB above the ISWEC signal. Within this distance from ISWEC, a possible masking effect is supposed

MARINE ECOSYSTEMS THROUGH THE LENS OF SOUNDSCAPE ECOLOGY: HOW BIOLOGICAL PROCESSES, LANDSCAPE STRUCTURE, AND ANTHROPOGENIC ACTIVITY AFFECT SPATIOTEMPORAL SOUNDSCAPE PATTERNS

Marine soundscapes, or the collection of all sounds across a landscape, consist of dynamic patterns resulting from natural and anthropogenic sound-producing processes. Soundscape ecology is focused on understanding how these processes interact with environmental variables and landscape structure to create dynamic soundscape patterns across space and time. As the field develops, there has been rising interest in using soundscapes as a tool to assess biodiversity and inform conservation and management decisions. However, understanding spatiotemporal soundscape patterns and their associations with ecological and environmental covariates is needed for passive acoustic monitoring to be informative. My dissertation addresses this need through two focal questions: (1) how do soundscapes vary across marine landscapes and is this variation explained by ecological metrics; and (2) how can soundscapes, or passive acoustic monitoring, be used to inform conservation and management priorities? To understand soundscape variation, I first compared the soundscapes of natural and artificial offshore reefs, finding that their temporal patterns were similar but spectral content differed. Following these results, I evaluated soundscape spatial variation across a range of estuarine habitat mosaics to explore whether soundscape differences between habitat types were associated with environmental metrics. I observed four distinct soundscape types that were associated with patch- and landscape-scale habitat metrics. Variation in all soundscape metrics summarized was explained by landscape-scale habitat metrics, while patch-scale metrics also explained sound levels, and abiotic metrics explained species-specific call rates. To evaluate how passive acoustic monitoring can be applied to conservation and management questions, I assessed whether soundscape monitoring was a useful complement to traditional video monitoring for tracking community development following deployment of an artificial reef. Comparing the soundscape of a newly deployed artificial reef to that of a nearby established reef revealed the colonization of multiple cryptic species that were not available from video monitoring. Lastly, I used multiple passive acoustic monitoring technologies to assess the spawning-associated grunt dynamics of Atlantic cod in a region with imminent offshore wind energy development. Elucidating the peak spawning period and aggregation site revealed that interactions between Atlantic cod spawning and offshore wind energy construction are likely. This dissertation advances understanding of soundscape variability in multiple ecosystems and demonstrates the benefit of passive acoustic monitoring for addressing applied ecological questions. By focusing on periods of peak acoustic activity and exploring variation across marine landscapes, my research explained previously undescribed soundscape variation and identified the relevance of landscape context in understanding marine soundscape variability. In applied contexts, my findings demonstrate that species-specific results are the most ecologically informative, but the current application of passive acoustic monitoring is limited by a lack of reliable identification of species-specific call types and associated call detectors. Advances in call detection will facilitate more nuanced ecological questions to be asked of marine soundscape and expand its relevance for addressing conservation and management priorities.Doctor of Philosoph

Caribbean Sea Soundscapes: Monitoring Humpback Whales, Biological Sounds, Geological Events, and Anthropogenic Impacts of Vessel Noise

Assessing marine soundscapes provides an understanding of the biological, geological and anthropogenic composition of a habitat, including species diversity, community composition, and human impacts. For this study, nine acoustic recorders were deployed between December 2016 and June 2017 off six Caribbean islands in several Marine Parks: the Dominican Republic (DR), St. Martin (SM), Guadeloupe east and west (GE, GW), Martinique (MA), Aruba (AR), and Bonaire (BO). Humpback whale song was recorded at five sites on four islands (DR, SM, GE, GW, and MA) and occurred on 49–93% of recording days. Song appeared first at the DR site and began 4–6 weeks later at GE, GW, and MA. No song was heard in AR and BO, the southernmost islands. A 2-week period was examined for the hourly presence of vessel noise and the number and duration of ship passages. Hourly vessel presence ranged from low (20% – DR, 30% – SM), medium (52% – MA, 54% – BO, 77% – GE) to near continuous (99% – GW; 100% – AR). Diurnal patterns were observed at BO, GE, and MA with few to no vessels present during night time hours, possibly reflecting the activity of recreational craft and fishing vessels. At the DR and GW sites, vessel traffic was ubiquitous for most of the day, likely reflecting heavy cruise ship and container ship presence. Soundscapes were diverse across islands with persistent fish choruses, sporadic sperm whale (Physeter macrocephalus) and dolphin (Delphinidae) presence at BO, minke whales (Balaenoptera acutorostrata) from late December to late February at MA and an earthquake recorded across all sites. These analyses provide an important first step in characterizing the health and species richness in Caribbean marine parks and demonstrate a surprising high anthropogenic foot print. Vessel traffic in particular contributes adversely to marine soundscapes, masking marine mammal sounds, potentially changing typical animal behavior and raising the risk of ship strike

The effects of physical, biological and anthropogenic noise on the occurrence of dolphins in the Pacific region of the Panama Canal

The main aim of this thesis was to investigate the occurrence of dolphins in Pacific waters adjacent to the Panama Canal in the context of biological, temporal and spatial factors. Acoustic data were collected at 101 sites at a range of distances and depths from the shipping region. Data were collected between March 2010 and April 2011 in a diurnal cycle over a total of 114 recording days. Received sound levels were split into 1/3 Octave bandwidths to study variation in sound pressure levels and then converted to spectrum density levels to show the sound components of the background noise in this region. Generalised Linear Models were used to relate dolphin whistle detections to temporal, spatial, environmental and acoustic variables. The major sources of background noise were biological noise from soniferous fish and snapping shrimp and anthropogenic noise from vessels characterised by mid to high frequencies produced by artisanal fishing boats. There was monthly and diurnal variation with some locations characterised by loud sounds in the mid to high frequencies at night. Whistle characteristics analysis revealed that the frequencies and range of the whistles were different to those previously reported under similar conditions. Whistles varied diurnally and in the presence of fish chorus and fishing boats. The study highlights a strong correlation between fish choruses and whistle detection. Temporal and spatial models showed that whistle detections varied monthly and in relation to fish noise and small vessel engine noise. Dolphins were distributed throughout most of the study area; however, whistle detections varied with distance from the coast. The results provide new knowledge about background noise composition in this region and provide the first information on the ecology of dolphin whistles in relation to this background noise, especially to fish chorus