Fish Sounds Research Articles

Spatial mapping of the biophony of the fishes living in seagrass meadows

Passive acoustics is well suited to assess the diversity and/or activity of marine animals, particularly if cryptic or difficult to observe as in seagrass Posidonia oceanica meadows. The ability to locate the emitters allows not only to detect the presence of a specific sound or specie but also to estimate source levels, the communicative space with respect to ambient noise and anthropogenic impact, the density of vocalizing animals, their movements and potentially home ranges, etc. Here, we located fishes in seagrass meadows (Calvi, France). Two particular sounds dominated the acoustic scene of seagrass meadows: the: 300 Hz drums of Ophidion rochei and the ubiquitous 800Hz /kwa/ sound of unknown origin. The wavelengths of these fish sounds range from 5 m to 2 m. During six 48-hours period, we deployed a squared array of 4 hydrophones (20 x 50 x 50 m). Here, we describe the algorithm for automated fish sound detection and 3D localization of the sources and assess their performances on our real data. Over 1000 fish sounds were detected per night. These detections were used to create localization maps and study the spatial distribution of fish sound production, estimate source levels and the density of the vocalizing fishes within the meadow and their limits.

Identification of fish species in estuaries and rivers using recorded soundscape with supervised machine learning

Identification of various fish species in estuarine and riverine environments is an important ecological problem at the intersection of various disciplines, including underwater acoustics, signal processing, and fisheries. Advancements in this field can be made by applying machine learning and deep learning technologies. From the vast amount of existing work on machine learning techniques, of special relevance to this problem are those aiming at the detection and labeling of speakers on overlapping speech, where the existing literature is much more reduced. In this paper, we present a dataset collected with a passive recorder placed on a tripod in Delaware Bay estuary during summer 2013 to continuously measure environmental soundscapes for several weeks. By using a library of mid-Atlantic region fish sounds as prior knowledge, we adapt the aforementioned techniques to the detection and identification of various recorded sounds. This adaptation is challenging, as the statistical properties of fish sounds are not the same as those of speech, and requires careful research on how to perform data pre-processing, feature extraction, and model development. The application of the proposed machine learning techniques to future observations will enhance the potential for long-term autonomous ecological studies in bays and rivers.

Sounds from the Amazon: Piranha and prey

The underwater soundscape of an upper tributary of the Amazon River was studied in a four-week survey from 3 to 26 July 2012 within the Pacaya-Samiria National Reserve, Peru. Over 550 individuals representing over 70 species of fishes were auditioned for sound production. In addition, over 641 minutes of natural sounds from the river were recorded from 22 sites. We demonstrate that closely related species of piranha can be distinguished by their hand-held disturbance sounds. Similar piranha sounds were recorded in the wild at locations where piranha were known to be actively feeding. Sounds of catfishes and other fishes were significantly more frequent at piranha feeding sites. Thus, piranha sounds appear to be excellent indicators of local piranha feeding activity and suggest that passive acoustic monitoring (PAM) can be an effective tool for studies on piranha behavior, feeding activity, and impact on prey fishes.

Automatic fish sounds classification.

The work presented in this paper focuses on the use of acoustic systems for passive acoustic monitoring of ocean vitality for fish populations. Specifically, it focuses on the use of acoustic systems for passive acoustic monitoring of ocean vitality for fish populations. To this end, various indicators can be used to monitor marine areas such as both the geographical and temporal evolution of fish populations. A discriminative model is built using supervised machine learning (random-forest and support-vector machines). Each acquisition is represented in a feature space, in which the patterns belonging to different semantic classes are as separable as possible. The set of features proposed for describing the acquisitions come from an extensive state of the art in various domains in which classification of acoustic signals is performed, including speech, music, and environmental acoustics. Furthermore, this study proposes to extract features from three representations of the data (time, frequency, and cepstral domains). The proposed classification scheme is tested on real fish sounds recorded on several areas, and achieves 96.9% correct classification compared to 72.5% when using reference state of the art features as descriptors. The classification scheme is also validated on continuous underwater recordings, thereby illustrating that it can be used to both detect and classify fish sounds in operational scenarios.

Cataloging fish sounds in the wild using combined acoustic and video recordings.

Although many fish are soniferous, few of their sounds have been identified, making passive acoustic monitoring (PAM) ineffective. To start addressing this issue, a portable 6-hydrophone array combined with a video camera was assembled to catalog fish sounds in the wild. Sounds are detected automatically in the acoustic recordings and localized in three dimensions using time-difference of arrivals and linearized inversion. Localizations are then combined with the video to identify the species producing the sounds. Uncertainty analyses show that fish are localized near the array with uncertainties < 50 cm. The proposed system was deployed off Cape Cod, MA and used to identify sounds produced by tautog (Tautoga onitis), demonstrating that the methodology can be used to build up a catalog of fish sounds that could be used for PAM and fisheries management.

Mating calls of three prochilodontid fish species from Brazil

Passive acoustic monitoring (PAM) of fish sounds has been used as a means of detecting the presence and abundance of fishes. Prior to PAM, bioacoustical analyses of sounds are needed to characterize species-specific characteristics of calls. With hydrophones placed in outdoor ponds, we recorded the mating calls of three species of prochilodontid fishes (Prochilodus argenteus, P. costatus, P. lineatus). Fish were induced to spawn and call by injection of carp (Cyprinus carpio) pituitary gland extract. We recorded a total of 394 pulse train calls and additional single pulse calls that were not associated with trains. The trains of all three species were similar in nature - series of low frequency pulses that lasted from 1 to 11 s, often with an initial rapid rise followed by a slow tapering of pulse amplitude. Dominant frequency of single pulses and trains was greatest in P. lineatus, with P. costatus and P. argenteus exhibiting lower single pulse dominant frequencies, and P. costatus having lower train dominant frequency. With data from the three species combined, the dominant frequency of pulses significantly increased with fish standard length. There was also a significant linear relationship between the dominant frequency of pulses and trains. Discriminant function analysis showed that differences in train dominant frequency, pulse duration, and pulse period between the three species were significant enough to discriminate between them. This study was the first to fully characterize the sounds of these three Prochilodus species, and should assist fisheries biologists monitoring spawning behavior in these species.

Diversity of fish sound types in the Pearl River Estuary, China.

BackgroundRepetitive species-specific sound enables the identification of the presence and behavior of soniferous species by acoustic means. Passive acoustic monitoring has been widely applied to monitor the spatial and temporal occurrence and behavior of calling species.MethodsUnderwater biological sounds in the Pearl River Estuary, China, were collected using passive acoustic monitoring, with special attention paid to fish sounds. A total of 1,408 suspected fish calls comprising 18,942 pulses were qualitatively analyzed using a customized acoustic analysis routine.ResultsWe identified a diversity of 66 types of fish sounds. In addition to single pulse, the sounds tended to have a pulse train structure. The pulses were characterized by an approximate 8 ms duration, with a peak frequency from 500 to 2,600 Hz and a majority of the energy below 4,000 Hz. The median inter-pulsepeak interval (IPPI) of most call types was 9 or 10 ms. Most call types with median IPPIs of 9 ms and 10 ms were observed at times that were exclusive from each other, suggesting that they might be produced by different species. According to the literature, the two section signal types of 1 + 1 and 1 + N10 might belong to big-snout croaker (Johnius macrorhynus), and 1 + N19 might be produced by Belanger’s croaker (J. belangerii).DiscussionCategorization of the baseline ambient biological sound is an important first step in mapping the spatial and temporal patterns of soniferous fishes. The next step is the identification of the species producing each sound. The distribution pattern of soniferous fishes will be helpful for the protection and management of local fishery resources and in marine environmental impact assessment. Since the local vulnerable Indo-Pacific humpback dolphin (Sousa chinensis) mainly preys on soniferous fishes, the fine-scale distribution pattern of soniferous fishes can aid in the conservation of this species. Additionally, prey and predator relationships can be observed when a database of species-identified sounds is completed.

Fish sound production in freshwater habitats of New England: Widespread occurrence of air movements sounds

We conducted a roving survey of five major river systems and adjacent, creek, lake, and pond habitats located within the northeastern United States. Fish sounds were recorded in 49% of 175 locations. Air movement sounds, including fast repetitive tick (FRT), occurred at 41% of the locations. Sluggish creeks had the highest occurrence of fish sounds (71%). Although highly variable, creeks and brooks had the lowest noise levels and rivers the highest. Fish sounds were more frequent in low noise habitats than high noise habitats, but the effect of masking on detection is not clear. Within main-stem river habitats, fish sound diversity tended to increase along a gradient from high elevation to the sea. Follow-up studies validated air movement sounds produced by alewife, white sucker, and brook, brown and rainbow trout through direct observation or in observations where only single species were present. Sounds produced by all five species are of the “air movement” type which is poorly understood but occurs widely in freshwater habitats. Although air movement sounds are likely incidental to physiological processes, they appear to be uniquely identifiable to species and, hence, hold promise for passive acoustic studies of freshwater soundscapes and fish behavior.

Auditioning fish for sound production in captivity to contribute to a catalogue of known fish sounds to inform regional passive acoustic studies

Passive Acoustic Monitoring (PAM) is increasingly used as a method to characterize underwater soundscapes and the impacts of noise on marine ecosystems. The natural sounds produced by marine mammals have been widely studied, enabling the use of PAM as an effective conservation tool. However, much less is known about fish sound production, particularly in the northeast Pacific. This lack of information makes it difficult to identify fish sounds that are present in long-term recordings and thus precluding accurate determination of fish species composition and evaluation of the effects of noise on fishes. In order to identify fish sounds in British Columbia soundscapes, we need catalogues of validated fish sounds from Pacific species. These catalogs will help in comparing validated examples to unknown sounds found in long-term autonomous recordings. Our goal is to contribute to building such catalogues and to fill knowledge gaps in fish acoustic behaviour to support studies on the impact of anthropogenic noise on Pacific fishes. We are collaborating with aquaria, ocean-based aquaculture facilities and commercial fisheries to monitor, audition, and record the acoustic behavior of captive and semi-captive fish species. Here, we will present the results of these studies.

Bioacoustic monitoring station in underwater sculpture

In the waters surrounding Cancun, pressures from development, tourism, and shipping threaten the second largest coral reef system in the world. Passive bioacoustic monitoring provides information about presence and activity of marine life and other environmental information, including during the night and inclement weather. The development and deployment of underwater reef-forming art structures provided a unique opportunity to listen to the stages of growth. Starting in 2012, an Ecological Acoustic Recorder was used to sample sounds at “The Listener” sculpture site in the Punta Nizuc Marine Protected Area in Quintana Roo, Mexico. Snapping shrimp and fish sounds were prevalent as well as sounds from boat motors. Diel patterns were characterized to inform management practices and assess efficacy of nighttime noise restrictions.

Comparative analysis of /kwa/ fish sounds recorded during an early ecoacoustics experiment in a Posidonia oceanica seagrass meadow (Ustica Island, 1999)

Passive acoustics enables studying marine habitats thanks to the sound production of their inhabitants. A key question is: “Can fish sounds be used as environmental proxies?” Posidonia oceanica (L.) Delile 1813 seagrass meadows constitute an important ecosystem of the Mediterranean Sea which protects many species of invertebrates and fishes, some of which producing sounds with distinctive features. An arched frequency modulation centred at 747 Hz which aurally sounds like /kwa/ is being investigated as an environmental proxy (Raick et al. 2017). Remarkably, these sounds were already noted as a distinctive feature of the soundscape recorded during an early acoustic ecology experiment, USTICA 99, which measured simultaneously photosynthetic gaseous exchange and fish migration at the scale of a Posidonia meadow (Hermand 2003). We revisit that dataset to describe the specific characteristics and variability of the early recorded /kwa/ sounds and make a comparison with our recent study carried out in France ab...

Do bioacoustic conditions reflect species diversity? A case study from four tropical marine habitats

New tools, such as passive acoustic monitoring, can be helpful for measuring levels of biodiversity in habitats that are otherwise difficult to sample. Here, we tested the utility of acoustic measurements in shallow coastal waters by conducting simultaneous bioacoustic and biodiversity surveys in four habitat types in Panama: mangrove, reef, seagrass, and sand. We found that acoustic measurements in the “low band” (&amp;lt;1000 Hz) were positively correlated with cryptic fish species richness. However, our 24-h acoustic recordings revealed a clear toadfish chorus at dusk, which masked other fish sounds and confounded results from newer acoustic indices such as acoustic entropy and acoustic complexity. Band level in the “high band” (3,000-10,000 Hz) did not differ across habitat types and was not significantly correlated to biodiversity measurements. Our study demonstrates that bioacoustic surveys can help scientists to identify certain cryptic, soniferous species, and should be used in tandem with traditional biodiversity surveys. Additional research is needed in the marine environment to validate the utility of the newer acoustic indices.

Passive acoustic localization of fish using a compact hydrophone array

Passive acoustic monitoring of fish in their natural environment is a research field of growing interest and importance. Although many fish species are soniferous, the characterization and biological understanding of their sounds are largely unknown. Many underwater acoustic recordings contain sounds likely produced by fish, but little information can be extracted from them due to the lack of fundamental knowledge about the behaviors they represent. Deploying small hydrophone arrays can help fill some of these knowledge gaps. Passive acoustic localization using fish calls received on multiple hydrophones can be used to estimate swimming speed, calling rate of individual fish, and source level of their calls. This paper focuses on the three-dimensional localization of fish using a compact array of 6 hydrophones using both simulated and measured data. Fish sounds were detected manually on one of the hydrophones. Time difference of arrivals (TDOAs) were then defined by cross correlating the detected signal with signals from the other hydrophones. Linearized Bayesian inversion was employed to localize fish sounds from the measured TDOAs. Localization uncertainties were below 10 cm inside the hydrophone array. Simulated annealing optimization was used to define the hydrophone configuration that could provide the smallest localization uncertainties.

Acoustic signaling in fish: Does it contribute to increased fitness?

Animals often use acoustic signals when competing for limited resources. However, knowledge on how vocal behavior contributes to individual fitness in fish lags considerably behind that for terrestrial taxa. Here, I provide examples on how fish acoustic signals may confer an advantage in gaining access to food and mates. Fish sounds provide information on fish motivation and quality which is relevant for mutual assessment during agonistic interactions, such as competitive feeding, and during mate choice. Fish sounds also play a role in synchronizing the reproductive behavior and gamete release to maximize external fertilization. Considering that anthropogenic noise is increasingly changing the natural soundscape that have shaped fish acoustic signals, there is an urgent demand to better understand the importance of acoustic communication for fish survival and fitness.

Comparison between the marine soundscape of recreational boat mooring areas with that of a pristine area in the Mediterranean: Evidence that such acoustic hot-spots are detrimental to ecologically sensitive habitats

We investigated the potential to use passive acoustics to access the impact of recreational boat mooring areas on ecologically sensitive habitats in the Western Mediterranean. One important consequence of the tourist industry in the region is that it targets the most pristine and ecologically sensitive habitats. Underwater sounds were recorded in mooring areas in Ibiza, Formentera and Tabarca harbors during high use and low use seasons and compared to recordings in the Tabarca Marine Protected area. At each location, we recorded sounds during 20 min at three different sites, for three random sampling times during the day. The percent of time occupied by selected biological (drums and croaks) and anthropogenic sounds (boat and mooring chain noises), and call rates of selected fish sounds were measured and compared among sites and seasons. Biological sounds contributed significantly less to the soundscape in mooring areas during the tourist season, and to the reserve in both seasons. Our study demonstrates ...

Designing a scalable passive acoustics network

To realize the potential of passive acoustics to study animal distribution and behavior over large spatial and temporal scales, systems capable of processing acoustic data remotely and transmitting those results to cloud systems are needed. Passive acoustic recorders have been important for allowing researchers to collect large amounts of data over long time periods, but they allow the decision of how to analyze the data to be delayed until after it is collected. Given the availability of inexpensive computing and cloud connectivity, one key challenge in developing a scalable passive acoustics network is deciding what is important to know. A prototype scalable passive acoustics node to detect dolphin whistles and measure sound levels corresponding to fish sounds, boat noise, and snapping shrimp has been developed. The decision was made to bin data over 10 minute periods (e.g., whistles per 10 minutes), and store only small amounts of raw data for quality control. The system takes advantage of recent developments in consumer level Internet of Things (IoT) tools so that the hardware is inexpensive and the cloud system can handle very large numbers of nodes.

Passive acoustic monitoring of nocturnal fish sounds in Quintana Roo, Mexico

The Mesoamerican Reef (MAR) system has major ecological and economic importance, yet faces threats to ecosystem health and is understudied. Current methods for monitoring marine life in the northern MAR system off the state of Quintana Roo, Mexico, are inadequate for assessing the nocturnal biology and ecology of fishes, including quantification of abundance and diversity. In the present study, a marine passive acoustic monitoring (MPAM) approach was initiated at a site within the MAR system to characterize localized temporal patterns in fish acoustic behavior. This is the first study to collect data on fish sound production at night in this region. Pulsed fish sounds were a major contributor to the nighttime soundscape and were persistent and low frequency (50–1000 Hz), with a wide range of pulse rates. Fish sounds were more frequent, more persistent, and more diverse at night than during the day. Nocturnally-active fish are a more important part of the local ecosystem than had previously been recognized. Implementation of MPAM in this area has great potential as a long-term fish monitoring technique.

Passive acoustic recording of Ophidion rochei calling activity in Calvi Bay (France)

AbstractPassive acoustic recording (PAR) systems are non‐invasive and allow researchers to collect data over large spatial and/or temporal scales. As fish sounds are species‐specific and repetitive, PAR can provide a large amount of data about spatio‐temporal variation in fish distribution and behaviors. Ophidion rochei, found in the Mediterranean and Black Seas, is a sand‐dwelling species, meaning that the behavior of this cryptic nocturnal fish cannot be observed in the field. Fortunately, male O. rochei produce long, multiple‐pulsed calls that are easy to identify. The aim of this study was to determine whether or not male calls are linked to reproduction behaviors. If so, PAR would allow a detailed description of the seasonal and daily rhythms in O. rochei reproduction behavior. A hydrophone was deployed from 18 July 2011 to 21 June 2012 and from 7 June 2013 to 2 July 2013 on a sandy area (42°34′48′′ N, 8°43′43′′ E) in front of the STARESO research station (NW Corsica). Male sounds were obtained only at night from late spring to early fall. The annual sound production period corresponds to the reproductive season of O. rochei. Sound production followed diel cycles: it was sustained for the entire night at the beginning of the sound production season but limited to shorter periods in the evening during the second half of the season. These differences in daily and seasonal sound production tempo can be used in future recordings to make inter‐annual comparisons and estimate the physiological state of the fish.

Interspecific variation of warning calls in piranhas: a comparative analysis.

Fish sounds are known to be species-specific, possessing unique temporal and spectral features. We have recorded and compared sounds in eight piranha species to evaluate the potential role of acoustic communication as a driving force in clade diversification. All piranha species showed the same kind of sound-producing mechanism: sonic muscles originate on vertebrae and attach to a tendon surrounding the bladder ventrally. Contractions of the sound-producing muscles force swimbladder vibration and dictate the fundamental frequency. It results the calling features of the eight piranha species logically share many common characteristics. In all the species, the calls are harmonic sounds composed of multiple continuous cycles. However, the sounds of Serrasalmus elongatus (higher number of cycles and high fundamental frequency) and S. manueli (long cycle periods and low fundamental frequency) are clearly distinguishable from the other species. The sonic mechanism being largely conserved throughout piranha evolution, acoustic communication can hardly be considered as the main driving force in the diversification process. However, sounds of some species are clearly distinguishable despite the short space for variations supporting the need for specific communication. Behavioural studies are needed to clearly understand the eventual role of the calls during spawning events.

Passive acoustic monitoring of fishes and a crustacean using a towed hydrophone in Tateyama bay

Passive acoustic monitoring is useful to observe presence of marine organisms such as marine mammals, fishes and crustaceans. We aimed to estimate the distribution of fishes and crustaceans using a towed hydrophone. A range-wide passive acoustic monitoring was conducted in Tateyama bay in Japan using R/V Takamaru (61t) on July, September and November in 2015 of day and night. The towed hydrophone (Towed Aquafeeler, AquaSound Inc., Japan) was used for the observation. The vessel cruised 5 knot on 5 lines to cover the focal survey area (N 35°020’—N 35°02’ and E 139°46—E 139°51). Recorded data with frequency from 100Hz to 20 kHz were analyzed. Recorded fish sounds have dominant frequency between 200 Hz and 1500 Hz and duration between 0.1 s and 2.1 s. Crustacean sound shows dominant frequency as 3 kHz–20 kHz with the duration of 10 ms—20 ms. Using these features, number of fish sounds was counted automatically using custom-made MATLAB program. Large number of the sounds were recorded in the nighttime than in the daytime. Most frequently received month was July. Both of the fish and crustacean sounds were observed in shallow water (&amp;lt;30m) showing acoustic presence map.