Acoustic and visual adaptations to predation risk: a predator affects communication in vocal female fish

Predation is an important ecological constraint that influences communication in animals. Fish respond to predators by adjusting their visual signaling behavior, but the responses in calling behavior in the presence of a visually detected predator are largely unknown. We hypothesize that fish will reduce visual and acoustic signaling including sound levels and avoid escalating fights in the presence of a predator. To test this we investigated dyadic contests in female croaking gouramis (Trichopsis vittata, Osphronemidae) in the presence and absence of a predator (Astronotus ocellatus, Cichlidae) in an adjoining tank. Agonistic behavior in T. vittata consists of lateral (visual) displays, antiparallel circling, and production of croaking sounds and may escalate to frontal displays. We analyzed the number and duration of lateral display bouts, the number, duration, sound pressure level, and dominant frequency of croaking sounds as well as contest outcomes. The number and duration of lateral displays decreased significantly in predator when compared with no-predator trials. Total number of sounds per contest dropped in parallel but no significant changes were observed in sound characteristics. In the presence of a predator, dyadic contests were decided or terminated during lateral displays and never escalated to frontal displays. The gouramis showed approaching behavior toward the predator between lateral displays. This is the first study supporting the hypothesis that predators reduce visual and acoustic signaling in a vocal fish. Sound properties, in contrast, did not change. Decreased signaling and the lack of escalating contests reduce the fish’s conspicuousness and thus predation threat.     

The diversity of ethological and physiological mechanisms of acoustic communication in insects

Mechanisms of producing and perceiving sound signals are considered for various phylogenetic branches of insects. This review discusses the means that allow sound signaling to match the environmental conditions and physiological state in insects. The evolution of acoustic communication is considered as a means of adaptation of insects to the environment.     

Fish Sound Production in the Presence of Harmful Algal Blooms in the Eastern Gulf of Mexico

This paper presents the first known research to examine sound production by fishes during harmful algal blooms (HABs). Most fish sound production is species-specific and repetitive, enabling passive acoustic monitoring to identify the distribution and behavior of soniferous species. Autonomous gliders that collect passive acoustic data and environmental data concurrently can be used to establish the oceanographic conditions surrounding sound-producing organisms. Three passive acoustic glider missions were conducted off west-central Florida in October 2011, and September and October 2012. The deployment period for two missions was dictated by the presence of red tide events with the glider path specifically set to encounter toxic Karenia brevis blooms (a.k.a red tides). Oceanographic conditions measured by the glider were significantly correlated to the variation in sounds from six known or suspected species of fish across the three missions with depth consistently being the most significant factor. At the time and space scales of this study, there was no detectable effect of red tide on sound production. Sounds were still recorded within red tide-affected waters from species with overlapping depth ranges. These results suggest that the fishes studied here did not alter their sound production nor migrate out of red tide-affected areas. Although these results are preliminary because of the limited measurements, the data and methods presented here provide a proof of principle and could serve as protocol for future studies on the effects of algal blooms on the behavior of soniferous fishes. To fully capture the effects of episodic events, we suggest that stationary or vertically profiling acoustic recorders and environmental sampling be used as a complement to glider measurements.     

First attempt to use a remotely operated vehicle to observe soniferous fish behavior in the Gulf of Maine, Western Atlantic Ocean

Underwater sound and video observations were made at noon, sunset, and midnight in sand, gravel, and boulder habitat in the Stellwagen Bank National Marine Sanctuary, Gulf of Maine, USA in October 2001 using a remotely operated vehicle (ROV). Seventeen species of fish and squid were observed with clear habitat and time differences. Observations of feeding behavior, disturbance behavior, and both interspecific and intraspecific interactions provided numerous opportunities for potential sound production; however, sounds were recorded only during a single dive. Although high noise levels generated by the ROV and support ship may have masked some sounds, we conclude that fish sound production in the Gulf of Maine during the fall is uncommon. The recorded fish sounds are tentatively attributed to the cusk Brosme brosme. Cusk sounds consisted variously of isolated thumps, widely spaced thump trains, drumrolls, and their combinations. Frequency peaks were observed at 188, 539, and 1195 Hz. Use of a remotely operated vehicle (ROV) as a passive acoustic observation platform was problematic due to high ROV self-noise and the ROV's inability to maintain a fixed position on the bottom without thruster power. Some fishes were clearly also disturbed by ROV noise, indicating a potential ROV sampling bias. Based on our observations, we suggest that new instruments incorporating both optic and passive acoustic technologies are needed to provide better tools for in situ behavioral studies of cusk and other fishes [Current Zoology 56 (1): 90-99 2010].     

FishSounds Version 1.0: A website for the compilation of fish sound production information and recordings

Many fish species use active sound production for communication in numerous behaviors. Additionally, likely all fish can make passive or incidental sounds that may also serve some signal functions. Despite the ecological importance of fish sounds, their evident passive acoustic monitoring applications, and extensive endeavors to document soniferous fish diversity, the fields of bioacoustics and ichthyology have historically lacked an easily accessible, global inventory of known fish sound production. To alleviate this limitation, we developed http://FishSounds.net, a website that compiles and disseminates fish sound production information and recordings. FishSounds Version 1.0 launched in 2021, cataloging documented examinations for active and passive sound production for 1185 fish species from 837 references as well as 239 exemplary audio recordings. FishSounds allows users to search by taxa (e.g., family or common name), geographical distribution (e.g., region or water body), sound type, or reference. We have also made available the code used to create the website, so that it may be used in other data-sharing efforts—acoustic or otherwise. Subsequent versions of the website will update the data and improve the website functionality. FishSounds will advance research into fish behavior, passive acoustic monitoring, and human impacts on underwater soundscapes; serve as a resource for public outreach; and provide the foundation needed to investigate more of the 96% of fish species that lack published examinations of sound production. We further hope the FishSounds design, implementation, and engagement strategies will serve as a model for future data management and sharing efforts.     

Correlation of acoustic and visual signals in the cichlid fish, <Emphasis Type="Italic">Tramitichromis intermedius</Emphasis>

We investigated acoustic and visual communication concurrently in wild caught adult and captive-born, first generation offspring of the East African Rift Lake cichlid fish Tramitichromis intermedius. Only males emit sound during courtship. Sound production is always accompanied by quivering, but quiver behavior is not always accompanied by sound. This separation of quivering and sound supports the hypothesis that sound production is intentional serving a communicative role. As spawning nears, both sound production and quiver behavior increase. In terms of the ontogeny of sound production, the first observation of courtship occurs just days before the first spawning event and the first sound emission accompanies the first courtship activity. The accompaniment of quivering with sound as well as the escalation of the two behaviors with the approach of spawning follows similar patterns in wild caught and captive-born males. The tight correlation between behavior and sound production in both groups indicates their simultaneous performance plays an important role in reproduction. It is probable that the ability to produce sound and perform quiver behavior at the same time may be a measure of mate quality.     

Four type of sounds for one winner: vocalizations during territorial behavior in the red-mouthed goby <Emphasis Type="Italic">Gobius cruentatus</Emphasis> (Pisces Gobiidae)

During territorial encounters, the acoustic repertoire of Gobius cruentatus consists of four types of sound emissions: a tonal sound, a noisy tonal sound, a train of individual pulses, and a complex sound. The complex sound is made of two distinct elements, an initial tonal part followed by pulses. This is the largest acoustic repertoire described so far in gobiid fish during aggressive interaction. Sounds are emitted, mainly by the residents, when fish have already started the interaction but before the encounter is settled. Therefore, sounds seem to have a threatening function.     

Feature-detecting auditory neurons in the brain of a sound-producing fish

The mormyrid fish Pollimyrus adspersus has auditory specializations for sound pressure detection and uses acoustic displays in its natural social behavior. In this paper it is shown that auditory neurons in the mesencephalon (torus semicircularis) are activated selectively by temporal features of complex sounds. Single neurons were recorded while presenting sounds to fish underwater. The stimuli were acoustic click trains, 400 ms in duration, and were synthesized with differing inter-click-intervals (ICIs). The natural sounds of this species are composed similarly and the range of ICIs synthesized overlapped with the natural range (5–40 ms). One-third of the neurons studied were strongly selective for a narrow range of ICIs, increasing spike rate by ten fold or more at the best ICI compared to the minimum response observed. The best ICI for interval selective neurons remained stable when the sound pressure of the stimulus was changed. Neurons that were selective gave phasic responses to tone bursts, and most had non-monotonic rate level functions. The origin of interval selectivity is discussed and a time-based computational mechanism is proposed. Accepted: 20 December 1996     

Ontogenesis of agonistic vocalizations in the cichlid fish Metriaclima zebra

While acoustic communication has been described in adults of various fish species, our knowledge about the ontogeny of fish sound production is limited. In adults, sound signals are known to be involved during aggressive interactions. However, aggressive behaviour may appear early in the life of fishes due to the possible competition for food and space. If acoustic signals are used to send information to competitors, sounds are likely to play a role during interactions between juvenile fish as well. The apparition and evolution of sound production were monitored in a group of juveniles of the cichlid fish Metriaclima zebra from hatching to 4months of age. In addition, the link between vocalizations and agonistic behaviour was studied during dyadic interactions at three different ages. Sounds production appeared to be present early in the development of this fish and increased along with the number of aggressive behaviours. Recorded sounds consisted, in juveniles, in isolated pulses showing a decrease in frequency and duration as the fish grew. In adults, sounds became bursts of pulses but the transition from isolated to repetitive pulses was not observed. These results are compared to the existing literature on sound production ontogeny in fishes.     

饲养状态真鲂(鱼弗)发声的昼夜与季节变化

本文研究了受水温和光周期等自然变化影响的饲养状态真鲂鮄发声的昼夜与季节变化,并研究了实验鱼活动(鱼类游泳次数)的日变化。声音信号的昼夜节律记录发声活动的日常水平(摄食之外的时期),但是每月变化的记录(季节性式型)则在摄食期间进行,因为摄食时声音信号增加,而日常发声活动较不频繁。实验鱼包括雌雄两性,且未达性成熟。真鲂鮄在白天发声多一些,也更活跃。声音为阵发式的,较不频繁(平均值=0.04发声/min每鱼每天)。最少的发声活动出现在晚上,凌晨和黄昏居中(声音的阵发更频繁,但是声音更少),最多的发声活动出现在白天(声音的阵发更频繁,并且含更多数目的声音)。竞争摄食时声音信号的比率不呈现季节性变化(平均值=3.98发声/min每鱼),与温度也不相关,显示出竞争摄食时声音的发出以最大比率进行。敲击声和呼噜声的某些声学特征与温度相关,特别是在较高的温度下呼噜声的节拍间隔急剧下降。敲击声和呼噜声的声音参数中的季节性变化,多数可以解释为发声肌肉和中央声音控制回路的温度效应。     

The African cichlid fish Astatotilapia burtoni uses acoustic communication for reproduction: sound production, hearing, and behavioral significance

Sexual reproduction in all animals depends on effective communication between signalers and receivers. Many fish species, especially the African cichlids, are well known for their bright coloration and the importance of visual signaling during courtship and mate choice, but little is known about what role acoustic communication plays during mating and how it contributes to sexual selection in this phenotypically diverse group of vertebrates. Here we examined acoustic communication during reproduction in the social cichlid fish, Astatotilapia burtoni. We characterized the sounds and associated behaviors produced by dominant males during courtship, tested for differences in hearing ability associated with female reproductive state and male social status, and then tested the hypothesis that female mate preference is influenced by male sound production. We show that dominant males produce intentional courtship sounds in close proximity to females, and that sounds are spectrally similar to their hearing abilities. Females were 2-5-fold more sensitive to low frequency sounds in the spectral range of male courtship sounds when they were sexually-receptive compared to during the mouthbrooding parental phase. Hearing thresholds were also negatively correlated with circulating sex-steroid levels in females but positively correlated in males, suggesting a potential role for steroids in reproductive-state auditory plasticity. Behavioral experiments showed that receptive females preferred to affiliate with males that were associated with playback of courtship sounds compared to noise controls, indicating that acoustic information is likely important for female mate choice. These data show for the first time in a Tanganyikan cichlid that acoustic communication is important during reproduction as part of a multimodal signaling repertoire, and that perception of auditory information changes depending on the animal's internal physiological state. Our results highlight the importance of examining non-visual sensory modalities as potential substrates for sexual selection contributing to the incredible phenotypic diversity of African cichlid fishes.     

Juvenile coral reef fish use sound to locate habitats

There is limited knowledge of the orientation cues used by reef fish in their movement among different habitats, especially those cues used during darkness. Although acoustic cues have been found to be important for settlement-stage fish as they seek settlement habitats, only a small number of studies support the possible role of acoustic cues in the orientation of post-settled and adult reef fish. Therefore, the aim of this study was to determine whether habitat-specific acoustic cues were involved in the nocturnal movements of juvenile reef fish to small experimental patch reefs that were broadcasting sound previously recorded from different habitats (Fringing Reef, Lagoon, Silent). Juvenile fish arriving at each patch reef were caught the next morning by divers and were identified. There were a greater number of occasions when juvenile fish (from all species together) moved onto the patch reefs broadcasting Fringing Reef and Lagoon sound (43 and 38%, respectively) compared to Silent reefs (19%) (χ² = 33.5; P < 0.05). There were significantly more occasions when juvenile fish from the family Nemipteridae were attracted to the patch reefs broadcasting Lagoon sound (63%) versus those reefs broadcasting either Fringing Reef sound (31%) or Silent (6%). In contrast, there were more occasions when juveniles from the family Pomacentridae were attracted to the patch reefs broadcasting Fringing Reef sound (56%) than either Lagoon (24%) or Silent patch reefs (20%) (χ² = 19.5; P < 0.05). These results indicate that some juvenile fish use specific habitat sounds to guide their nocturnal movements. Therefore, the fish are able to not only use the directional information contained in acoustic cues, but can also interpret the content of the acoustic signals for relevant habitat information which is then used in their decision-making for orientation.     

Geographical variation in sound production in the anemonefish Amphiprion akallopisos

Because of pelagic-larval dispersal, coral-reef fishes are distributed widely with minimal genetic differentiation between populations. Amphiprion akallopisos, a clownfish that uses sound production to defend its anemone territory, has a wide but disjunct distribution in the Indian Ocean. We compared sounds produced by these fishes from populations in Madagascar and Indonesia, a distance of 6500 km. Differentiation of agonistic calls into distinct types indicates a complexity not previously recorded in fishes' acoustic communication. Moreover, various acoustic parameters, including peak frequency, pulse duration, number of peaks per pulse, differed between the two populations. The geographic comparison is the first to demonstrate 'dialects' in a marine fish species, and these differences in sound parameters suggest genetic divergence between these two populations. These results highlight the possible approach for investigating the role of sounds in fish behaviour in reproductive divergence and speciation.     

Acoustic deterrents to manage fish populations

Finding effective ways to direct native fish away from anthropogenic hazards and limit the spread of invasive species, without physical intervention, harming non-target fishes or interrupting aquatic commerce is a major challenge for fisheries management. One option is to target fish sensory systems to manipulate behavior using attractive or repulsive cues. Many, if not all species of fish, use sound as part of their behavioral repertoire and display varying degrees of phonotaxis. Sound has inherent advantages over other sensory stimuli such as light or odor as underwater sound attenuates slowly, is highly directional and is unimpeded by low light or water turbidity. This review details the use of acoustics to deter and guide fish movements for a wide variety of fishes, before critically assessing the benefits and limitations of the technology. No single method of fish deterrence is a “one size fits all”, and therefore this review will assist both managers and researchers attempting to use acoustic deterrents for different fish orders.

     

Acoustic signalling in female fish: factors influencing sound characteristics in croaking gouramis

The characteristics of sounds produced by fishes are influenced by several factors such as size. The current study analyses factors affecting structural properties of acoustic signals produced by female croaking gouramis Trichopsis vittata during agonistic interactions. Female sounds (although seldom analysed separately from male sounds) can equally be used to investigate factors affecting the sound characteristics in fish. Sound structure, dominant frequency and sound pressure levels (SPL) were determined and correlated to body size and the order in which sounds were emitted. Croaking sounds consisted of series of single-pulsed or double-pulsed bursts, each burst produced by one pectoral fin. Main energies were concentrated between 1.3 and 1.5 kHz. The dominant frequency decreased with size, as did the percentage of single-pulsed bursts within croaking sounds. The SPL and the number of bursts within a sound were independent of size but decreased significantly with the order of their production. Thus, acoustic signals produced at the beginning of agonistic interactions were louder and consisted of more bursts than subsequent ones. Our data indicate that body size affects the dominant frequency and structure of sounds. The increase in the percentage of double-pulsed bursts with size may be due to stronger pectoral muscles in larger fish. In contrast, ongoing fights apparently result in muscle fatigue and subsequently in a decline in the number of bursts and SPL. The factor ‘order of sound production’ points to an intra-individual variability of sounds and should be considered in future studies.     

摄食声对草鱼幼鱼的诱集作用

以草鱼(Ctenopharyngodon idellus)幼鱼为实验对象,进行了声音播放实验,旨在探究草鱼幼鱼对水下录制的草鱼摄食浮萍声音(简称摄食声)的行为反应。以不播放声音的草鱼鱼群作为对照,探讨了4种单频音(500、1000、2000和3000 Hz)和摄食声对草鱼游泳行为和在水槽内的分布的影响。结果表明:在播放单频音时, 3min内草鱼的趋音游泳速度和逗留时间与对照组无显著性差异(P>0.05);在播放摄食声时, 3min内草鱼的趋音游泳速度和逗留时间显著高于4种单频音组和对照组(P<0.05);在播放单频音时, 20min内草鱼的平均游泳速度、水槽内的分布和趋音率与对照组无显著性差异(P>0.05);在播放摄食声时, 20min内草鱼的平均游泳速度和趋音率都显著高于4种单频音组和对照组(P<0.05)。草鱼摄食声对草鱼幼鱼有诱集作用,为声音诱鱼技术研究提供了科学依据。     

Acoustic barriers as an acoustic deterrent for native potamodromous migratory fish species

This study focused on the use of sound playbacks as acoustic deterrents to direct native potamodromous migratory species away from all kind of traps. The effects of two acoustic treatments, a repeated sine sweep up to 2 kHz (sweep-up stimulus) and an intermittent 140 Hz tone, were tested in three fish species native to Iberia: Salmo trutta, Pseudochondrostoma duriense and Luciobarbus bocagei. In contrast with S. trutta, the endemic cyprinids P. duriense and L. bocagei exhibited a strong repulse reaction to the frequency sweep-up sound. The 140 Hz stimulus did not seem to alter significantly the behaviour of any of the studied species. These results highlight the potential of acoustic stimuli as fish behavioural barriers and their application to in situ conservation measures of native Iberian fish populations, to protect them from hydropower dams. In addition, this study shows that acoustic deterrents can be used selectively on target species.     

Learned or innate production of acoustic signals in fishes: a test using a cyprinid

No information on the inheritance of the ability to produce sounds exists for fishes. In birds, which usually provide extensive post-hatching parental care, acoustic signals are learned in some species but are innate in others. Almost no fishes provide extensive post-hatching parental care and, consequently, the offspring have little opportunity to hear and learn sounds produced by the parents (usually the male in fishes); they may, however, be exposed to acoustic signals of conspecifics in the same habitat. We used a cyprinid, Codoma ornata, to test whether sound production is learned from the parents or whether it is innate. Fertilized eggs of this species were raised in isolation from adults. Upon maturity, these fish were tested for sound production in aggressive and reproductive contexts. Fish which had no contact with adults, and therefore no opportunity to hear the acoustic signals of their species, produced sounds that were similar to those produced by their parents, and they produced these in the same contexts. Significant differences were observed in dominant frequency for one context, with the smaller F₁ fish having signals of higher frequency than parental fish. Since no opportunity for learning existed, this provided evidence that the ability to produce sounds is innate in this minnow species.     

3-D-orientation with the octavolateralis system.

Fish detect and localize a sound source with inner ear receptors and with the mechanosensory lateral line. The inner ear of fish is sensitive to the water displacements caused by sound waves through a direct, inertial response by hair cell epithelia of the ear. Hearing specialists, such as goldfish and herring, have accessory peripheral structures that provide additional sensitivity to the pressure component of a sound wave. While the inner ear of fish responds to the whole body motions caused by sound waves and--in case of hearing specialists--to sound pressure, the lateral line is only sensitive to water motions relative to the surface of the fish and to local pressure gradients. Using lateral line and/or acoustic input, some fish can determine the direction and the distance to a sound source. Most likely they do so by exploiting some of the mechanisms described in this paper. Piscivorous fish may use lateral line input to detect the wakes caused by swimming fish. Even in the absence of light catfish, for instance, can follow a 10 s old, three-dimensional wake left by a prey fish over distances up to 55 prey-body length.     

Calling Behavior and Morphology of the Stridulatory Apparatus in Neotropical Grasshoppers (Aleuas Stål; Orthoptera)

The sound production and sound producing apparatus of two species of grasshoppers, A. lineatus Stål, 1878 and A. vitticollis Stål, 1878 (Orthoptera, Acrididae, Copiocerinae) have been studied. For both species oscillograms and other physical data on sounds are presented for the first time. The sound producing behavior is described and the stridulation apparatus mechanism is illustrated. In the case of A. vitticollis these data are the first known on its sound production and general acoustic behavior.