Article

Ontogeny of Acoustic and Feeding Behaviour in the Grey Gurnard

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Abstract

Although sound production in teleost fish is often associated with territorial behaviour, little is known of fish acoustic behaviour in other agonistic contexts such as competitive feeding and how it changes during ontogeny. The grey gurnard, Eutrigla gurnardus, frequently emits knock and grunt sounds during competitive feeding and seems to adopt both contest and scramble tactics under defensible resource conditions. Here we examine, for the first time, the effect of fish size on sound production and agonistic behaviour during competitive feeding. We have made sound (alone) and video (synchronized image and sound) recordings of grey gurnards during competitive feeding interactions. Experimental fish ranged from small juveniles to large adults and were grouped in four size classes: 10–15, 15–20, 25–30 and 30–40 cm in total length. We show that, in this species, both sound production and feeding behaviour change with fish size. Sound production rate decreased in larger fish. Sound duration, pulse duration and the number of pulses increased whereas the peak frequency decreased with fish size, in both sound types (knocks and grunts). Interaction rate and the frequency of agonistic behaviour decreased with increasing fish size during competitive feeding sessions. The proportion of feeding interactions accompanied by sound production was similar in all size classes. However, the proportion of interactions accompanied by knocks (less aggressive sounds) and by grunts (more aggressive) increased and decreased with fish size, respectively. Taken together, these results suggest that smaller grey gurnards compete for food by contest tactics whereas larger specimens predominantly scramble for food, probably because body size gives an advantage in locating, capturing and handling prey. We further suggest that sounds emitted during feeding may potentially give information on the motivation and ability of the individual to compete for food resources.

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... These protrusions are called rami Mülleri, or (more often) elastic springs. 8 These structures are connected with the swim bladder by means of the ligaments (Bridge and Haddon, 1893; Tavolga, 1962;Ladich and Fine, 2006;Parmentier and Diogo, 2006). ...
... In these cases, the sonic muscles are absent (Bridge and Haddon, 1893). 8 The name of the protrusions was given in honor of J. Müller, the German scientist who described these structures in fishes for the first time in 1842. sonic muscles together. ...
... In Zosterisessor ophiocephalus with an increase of the body length is accompanied by a decrease of the sound frequency on the average by 200 Hz (Myrberg et al., 1993). Lower sound frequencies at increasing body size are registered in many other fishes, and this principle is usual, most likely, for many kinds of pulsed sounds irrespective of the mechanism of their generation (drumming, stridulation, stringed, etc.) ( Table 3 and Fig. 35) (Schneider, 1964;Bayoumi, 1970;Ladich et al., 1992b;Ladich, 1997;Loesser et al., 1997;Colson et al., 1998;Henglmüller and Ladich, 1999;Amorim, Hawkins, 2005). Similar ontogenetic changes are registered in other vertebrates: amphibians, birds, and primates (Würdinger, 1970;Davies and Haliday, 1978;Hohmann, 1991). ...
Article
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The main information on the sounds and sound production in fishes is reviewed. The present systems of sound classification and specialized sound production in fishes with different taxonomic positions and ecology are described. The anatomy of sound generating organs is analyzed, and the mechanisms of production of different types of sounds (stridulation, drumming, cavitation, and percussion, as well as hydrodynamic, pneumatic, stringed, and respiratory sounds) are discussed. A brief characterization of the acoustic parameters of different sound types is given. Recent data on the anatomy and morphology of the sonic muscles (including their innervation, physiology, sexual dimorphism, and seasonal changes) are reviewed. The dynamics of the development of sound generating organs are described, and their capacity for sound production in the ontogeny of fishes is followed.
... Ontogenetic development of sound production in fishes seems to follow a consistent pattern. Dominant frequencies of sounds decrease with size, for example in gurnards, mormyrids, croaking gouramis, damselfish and toadfish [17,19,212223242526. In most species tested in those studies, sound pressure levels, total duration of sounds as well as pulse periods within sounds increased. ...
... These patterns agree with the current data in Synodontis schoutedeni. The dominant frequency of sounds is negatively correlated with body size in representatives of all families investigated so far, for example, in pomacentrids -Stegastes partitus, Dascyllus albisella, Amphiprion akallopisos , A. clarkii, A. frenatus, A. ocellaris, [23,26,34,35], osphronemids -Trichopsis vittata, T. pumila and T. schalleri [17,21,22], sciaenids -Cynoscion regalis [36], triglids -Eutrigla gurnardus [25] , and toadfishes -Halobatrachus didactylus [19]. Fine et al. [37] found a decrease of center frequency in the ictalurid catfish Ictalurus punctatus. ...
... This can be explained by the growth of the dorsal process of the pectoral spine and the fact that a full pectoral sweep takes longer in larger fish than in a smaller one [37,40]. Increases with size have also been observed for pulse period in the Lusitanian toadfish [19], pulse duration in weakfish [36], and grunt duration in the grey gurnard [25]. ...
Article
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Surveys of ontogenetic development of hearing and sound production in fish are scarce, and the ontogenetic development of acoustic communication has been investigated in only two fish species so far. Studies on the labyrinth fish Trichopsis vittata and the toadfish Halobatrachus didactylus show that the ability to detect conspecific sounds develops during growth. In otophysine fish, which are characterized by Weberian ossicles and improved hearing sensitivities, the ontogenetic development of sound communication has never been investigated. We analysed the ontogeny of the auditory sensitivity and vocalizations in the mochokid catfish Synodontis schoutedeni. Mochokid catfishes of the genus Synodontis are commonly called squeakers because they produce broadband stridulation sounds during abduction and adduction of pectoral fin spines. Fish from six different size groups - from 22 mm standard length to 126 mm - were studied. Hearing thresholds were measured between 50 Hz and 6 kHz using the auditory evoked potentials recording technique; stridulation sounds were recorded and their sound pressure levels determined. Finally, absolute sound power spectra were compared to auditory sensitivity curves within each size group. The smallest juveniles showed the poorest hearing abilities of all size groups between 50 and 1,000 Hz and highest hearing sensitivity at 5 and 6 kHz. The duration of abduction and adduction sounds and the pulse period increased and sound pressure level (in animals smaller than 58 mm) increased, while the dominant frequency of sounds decreased with size in animals larger than 37 mm. Comparisons between audiograms and sound spectra revealed that the most sensitive frequencies correlate with the dominant frequencies of stridulation sounds in all S. schoutedeni size groups and that all specimens are able to detect sounds of all size groups. This study on the squeaker catfish S. schoutedeni is the first to demonstrate that absolute hearing sensitivity changes during ontogeny in an otophysine fish. This contrasts with prior studies on two cypriniform fish species in which no such change could be observed. Furthermore, S. schoutedeni can detect conspecific sounds at all stages of development, again contrasting with prior findings in fishes.
... In these drumming fishes, the muscle contraction rate sets the fundamental frequency [12,[18][19][20][21]; i.e. contraction of sonic muscles at 200 Hz will drive a harmonic sound with a fundamental frequency of 200 Hz. It implies that the time frame to perform a contraction/relaxation cycle is very short: toadfish sonic muscles require about 10 ms for a twitch [4,18] and the EMGs of weakfish sonic muscle twitches range from 7.9-13.6 ...
... In contrast, fish growth was related to a simultaneous decrease in the fundamental frequency. The impact of fish size on spectral and some temporal features such as pulse duration is well-known in distantly related fish families [21,[48][49][50][51][52][53]. The slope of this relationship is, however, generally less sizeable in fish whose sound production is based on a forced response of the swim bladder by the high-speed contraction of sonic muscles. ...
... In other words, the high slope value of the correlation between fish size and dominant frequency in the clownfish indicates that the size of the emitter can be assessed by the receiver and so be used in sonic communication. In the grunt of the gurnard Eutrigla gurnardus [21], in the weakfish Cynoscion regalis [23,50], in the toadfish Halobatrachus didactylus [54], in the holocentrids [55], and in Pygocentrus nattereri, this kind of relationship has also been statistically established. However, the slope value of the relationship is very weak and it is difficult to determine whether the fish can discriminate the spectral characteristic of the call as in the previous group. ...
Article
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Drumming muscles of some sound-producing fish are 'champions' of contraction speed, their rate setting the fundamental frequency. In the piranha, contraction of these muscles at 150 Hz drives a sound at the same frequency. Drumming muscles of different not closely related species show evolutionary convergences. Interestingly, some characters of sonic muscles can also be found in the trunk muscles of newly hatched larvae that are able to maintain tail beat frequencies up to 100 Hz. The aim of this work was to study the development of sound production and sonic and epaxial muscles simultaneously in the red bellied piranhas (Pygocentrus nattereri) to seek for possible common characteristics. Call, pulse and period durations increased significantly with the fish size, but the call dominant frequencies decreased, and the number of pulses and the call amplitude formed a bell curve. In epaxial muscles, the fibre diameters of younger fish are first positioned in the graphical slope corresponding to sonic muscles, before diverging. The fibre diameter of older fish trunk muscles was bigger, and the area of the myofibrils was larger than in sonic muscles. Moreover, in two of the biggest fish, the sonic muscles were invaded by fat cells and the sonic muscle ultrastructure was similar to the epaxial one. These two fish were also unable to produce any sound, meaning they lost their ability to contract quickly. The volume occupied by myofibrils determines the force of contraction, the volume of sarcoplasmic reticulum sets the contraction frequency, and the volume of mitochondria sets the level of sustained performance. The functional outcomes in muscles are all attributable to shifts in the proportions of those structures. A single delay in the development restricts the quantity of myofibrils, maintains a high proportion of space in the sarcoplasm and develops sarcoplasmic reticulum. High-speed sonic muscles could thus be skeletal muscles with delayed development. This hypothesis has the advantage that it could easily explain why high-speed sonic muscles have evolved so many times in different lineages.
... In general, the vocal repertoire of a single species is limited to one or two types of sounds, though in some species it may be more extensive [10]. Members of families with extensive vocal repertoires include the toadfishes (Batrachoididae) [11][12][13], elephantfish (Mormyridae) [14,15], gobies (Gobiidae) [16], damselfishes (Pomacentridae) [17] and gurnards (Triglidaeae) [18][19][20][21]. Within a fish species, the extent of a vocal repertoire and the seasonal and daily use of vocalisation may reflect biological function in a way that is useful to the interpretation of acoustic soundscapes. ...
... The vocalisation activity and behavioural context of sound production for the bluefin gurnard is currently unknown. In other gurnard species, the grey (Eutrigla gurnadus), streaked (Trigloporus lastoviza), tub (Trigla lucerna), red gurnard (Aspitrigla cuculus), northern sea robin (Prionotus carolinus) and striped sea robin (Prionotus evolans) has been reported to produce agonistic vocalisation sounds [8,18,19,21]. During competitive feeding, the streaked gurnard, northern and striped sea robin only produced one type of sound (described as a growl, squawk and grunt, respectively) as opposed to the grey gurnard which produced three types of sound (knocks, grunts and growl). ...
... Bluefin gurnard has a relatively large sound repertoire in comparison to those reported for other Triglidae species, such as the European grey gurnard (three types of sound), tub gurnard (two types) and the streaked gurnard (two types) [8,19,21]. The acoustic features of bluefin gurnard vocalisation also showed some marked differences to these other Triglidaes. ...
Article
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Fish vocalisation is often a major component of underwater soundscapes. Therefore, interpretation of these soundscapes requires an understanding of the vocalisation characteristics of common soniferous fish species. This study of captive female bluefin gurnard, Chelidonichthys kumu, aims to formally characterise their vocalisation sounds and daily pattern of sound production. Four types of sound were produced and characterised, twice as many as previously reported in this species. These sounds fit two aural categories; grunt and growl, the mean peak frequencies for which ranged between 129 to 215 Hz. This species vocalized throughout the 24 hour period at an average rate of (18.5 ± 2.0 sounds fish-1 h-1) with an increase in vocalization rate at dawn and dusk. Competitive feeding did not elevate vocalisation as has been found in other gurnard species. Bluefin gurnard are common in coastal waters of New Zealand, Australia and Japan and, given their vocalization rate, are likely to be significant contributors to ambient underwater soundscape in these areas.
... The same changes in acoustic features were found in the grey gurnard Eutrigla gurnardus (L. 1758) [9] and in the squeaker catfish Synodontis schoutedeni (David 1936) [10]. In the Lusitanian toadfish Halobatrachus didactylus (Bloch & Schneider 1801), sound production appears in small individuals after a few months of age (4 cm in size) [11]. ...
... The studies focusing on the ontogenesis of vocalizations in fishes performed so far [8][9][10][11]20] and the results presented here may reveal general patterns in the changes of temporal and spectral characteristics observed during the development of juvenile fish. First sounds usually consist in single isolated units of the future adult sounds. ...
Article
Full-text available
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 4 months 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.
... Larval snapper sounds recorded in the field versus those produced in the laboratory had different acoustic parameters: field knocks were higher in dominant frequency than tank knocks. While the duration of growls was generally greater in the tank than in the field, duration was highly variable even within individuals, suggesting some degree of behavioural plasticity (table 1 and figure 2 [16]). Several tank-based studies have demonstrated sound production in juvenile fish (e.g. ...
... Several tank-based studies have demonstrated sound production in juvenile fish (e.g. grey gurnard (Eutrigla gurnardus) at less than 1 year: [16], croaking gourami (Trichopsis vittata) at eight weeks [18], squirrelfish (Holocentridae) at settlement-stage [21]). Our results provide the first evidence for sound production during the pre-settlement stage of marine fishes and highlight the importance of in situ Lagrangian recording systems for future studies. ...
Article
The acoustic ecology of marine fishes has traditionally focused on adults, while overlooking the early life-history stages. Here, we document the first acoustic recordings of pre-settlement stage grey snapper larvae (Lutjanus griseus). Through a combination of in situ and unprovoked laboratory recordings, we found that L. griseus larvae are acoustically active during the night, producing ‘knock’ and ‘growl’ sounds that are spectrally and tem- porally similar to those of adults. While the exact function and physiological mechanisms of sound production in fish larvae are unknown, we suggest that these sounds may enable snapper larvae to maintain group cohesion at night when visual cues are reduced.
... Role of PJA in relation to sound production A large number of fishes produce sounds in different social context such as agonistic interactions, courtship and competitive feeding (Amorim et al., 2003;Amorim & Hawkins, 2005;Bertucci et al., 2010;Colleye & Parmentier, 2012;Ladich, 1997;Lobel, 1998;Longrie et al., 2013;Parmentier et al., 2010) [4,3,8,14,8,40,41,49] . Sound production does not rely on the same kind of mechanism in all teleost fishes that have evolved a high diversity of sound producing mechanism (Amorim, 2006;) [2,33] . ...
... Role of PJA in relation to sound production A large number of fishes produce sounds in different social context such as agonistic interactions, courtship and competitive feeding (Amorim et al., 2003;Amorim & Hawkins, 2005;Bertucci et al., 2010;Colleye & Parmentier, 2012;Ladich, 1997;Lobel, 1998;Longrie et al., 2013;Parmentier et al., 2010) [4,3,8,14,8,40,41,49] . Sound production does not rely on the same kind of mechanism in all teleost fishes that have evolved a high diversity of sound producing mechanism (Amorim, 2006;) [2,33] . ...
Article
Full-text available
Pharyngeal jaw apparatus is complex musculo-skeletal system which are modification of gill arch elements that is useful for masticating and transporting of food material. It consist of two independent upper plate and single fused lower plate that are containing various types of unicuspid, bicuspid or molariform dentition. Relationship between pharyngeal jaw for feeding and sound production may have profound evolutionary implications. It has serving as a possible mechanism for sound production; trophic biology and reproductive biology could be directly linked by this structure. Consequently, the dual use of the pharyngeal jaw may serve as a mechanism mediating the sympatric speciation of cichlid fishes. Intraspecific pharyngeal variations also occurred in some fishes that helpful to understanding lineage relationships.
... In these examples, the high slope value of the correlation between fish size and dominant frequency indicates that the size of the emitter can be assessed by the receiver and so be used in sonic communication. In the grunt of the gurnard Eutrigla gurnardus [22] , in the weakfish Cynoscion rega- lis [23], in the toadfish Halobatrachus didactylus [24] and in the holocentrids of this study, this kind of relationship has also been statistically established. However, the slope value is very weak and it is difficult to determine whether the fish can discriminate the spectral characteristic of the call as in the previous group. ...
... In Myripristis, we showed the number of pulses and their amplitudes were lower in the larvae than in the adults. Although the mechanisms are not the same, these results are in concordance with studies involving fishes from other taxa: the croaking gourami T. vittata [16,39] and the gurnard E. gurnardus [22]. Dialects have already been established in different fish species40414243. ...
Article
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: Holocentrids (squirrelfish and soldierfish) are vocal reef fishes whose calls and sound-producing mechanisms have been studied in some species only. The present study aims to compare sound-producing mechanisms in different Holocentridae genera (Holocentrus, Myripristis, Neoniphon, Sargocentron) from separate regions and, in some cases, at different developmental stages. An accurate comparison was made by recording six species while being hand-held, by observing TEM) the sonic muscles and by dissections of the sound-producing mechanism. In all these species, calls presented harmonics, their dominant frequency was between 80 and 130 Hz and they were composed of trains of 4 to 11 pulses with gradual increasing periods towards the end of the call. In each case, the calls did not provide reliable information on fish size. The sounds were produced by homologous fast-contracting sonic muscles that insert on articulated ribs whose proximal heads are integrated into the swimbladder: each pulse is the result of the back and forth movements of the ribs. Small differences in the shape of the oscillograms of the different species could be related to the number of ribs that are involved in the sound-producing mechanism. These fish species are able to make sounds as soon as they settle on the reef, when they are 40 days old. Comparison between Neoniphon from Madagascar and from Rangiroa in French Polynesia showed a new, unexpected kind of dialect involving differences at the level of pulse distribution. Neoniphon calls were characterised by a single pulse that was isolated at the beginning of the remaining train in Madagascar whereas they did not show any isolated single pulses at the beginning of the call in Rangiroa. This family cannot use the acoustic fundamental frequencies (or pulse periods) of grunts to infer the size of partners. Pulse duration and number of pulses are statistically related to fish size. However, these characteristics are poorly informative because the correlation slope values are weak. It remains other features (sound amplitude, resistance to muscle fatigue, calling frequency) could be used to assess the body size. Characteristics of the sound producing mechanisms are conservative. All species possess fast-contracting muscles and have the same kind of sound producing mechanism. They do show some change between clades but these differences are not important enough to deeply modify the waveforms of the calls. In this case, our description of the grunt could be considered as the signature for the holocentrid family and can be used in passive acoustic monitoring.
... Correlations between signal structure and size or age are evident in those ontogenetic studies in which size differs considerably between stages. Temporal patterns, dominant (peak) sound frequencies and sound levels were found to be correlated to age or size (Henglmüller and Ladich 1999;Wysocki and Ladich 2001;Amorim and Hawkins 2005;Lechner et al. 2010;Vasconcelos and Ladich 2008;reviewed in Ladich 2015b). ...
... Temporal characteristics such as sound duration, number of burst/pulses within sounds, pulse duration and burst/pulse periods typically increased with growth or size in all species studied (eg Amorim and Hawkins 2005;Connaughton et al. 2000;Colleye et al. 2009;Tellechea et al. 2010a;2010b, Knight andLadich 2014;Hadjiaghai and Ladich 2015), The few exceptions include the toadfish H. didactylus, in which the number of pulses within a sound and thus sound duration decreased as size increased during ontogeny (Vasconcelos and Ladich 2008). Ladich (1997) and Pruzsinszky and Ladich (1998) showed that sound duration depended on the size of the sound-generating mechanisms, namely the length of the pectoral spine in 7 catfish species from 4 families. ...
Article
Full-text available
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.
... The refinement in some of these signal characteristics with age is probably due to ontogenetic changes in the size and/or resonance properties of the soundgenerating apparatus (e.g. Myrberg et al., 1993;Amorim and Hawkins, 2005;Lechner et al., 2010). It remains unclear whether fish that produce more complex acoustic signals exhibit vocal differentiation, which could potentially result from ontogenetic modifications of the motor circuitry of the vocal pathways as in birds or mammals (e.g. ...
... Previous studies in other fish species reported developmental changes in acoustic features of vocalisations such as amplitude, dominant frequency and temporal patterns (e.g. gurnards, Amorim and Hawkins, 2005;catfishes, Lechner et al., 2010;gouramis, Henglmüller and Ladich, 1999;Wysocki and Ladich, 2001). However, these studies never reported developmental changes in the vocal repertoire or vocal differentiation, probably because the vocal repertoire was more restricted and the sounds produced were not as elaborate as, for instance, those produced by batrachoidids (Amorim et al., 2008). ...
Article
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Vocal differentiation is widely documented in birds and mammals but has been poorly investigated in other vertebrates, including fish, which represent the oldest extant vertebrate group. Neural circuitry controlling vocal behaviour is thought to have evolved from conserved brain areas that originated in fish, making this taxon key to understanding the evolution and development of the vertebrate vocal-auditory systems. This study examines ontogenetic changes in the vocal repertoire and whether vocal differentiation parallels auditory development in the Lusitanian toadfish Halobatrachus didactylus (Batrachoididae). This species exhibits a complex acoustic repertoire and is vocally active during early development. Vocalisations were recorded during social interactions for four size groups (fry: <2 cm; small juveniles: 2-4 cm; large juveniles: 5-7 cm; adults >25 cm, standard length). Auditory sensitivity of juveniles and adults was determined based on evoked potentials recorded from the inner ear saccule in response to pure tones of 75-945 Hz. We show an ontogenetic increment in the vocal repertoire from simple broadband-pulsed 'grunts' that later differentiate into four distinct vocalisations, including low-frequency amplitude-modulated 'boatwhistles'. Whereas fry emitted mostly single grunts, large juveniles exhibited vocalisations similar to the adult vocal repertoire. Saccular sensitivity revealed a three-fold enhancement at most frequencies tested from small to large juveniles; however, large juveniles were similar in sensitivity to adults. We provide the first clear evidence of ontogenetic vocal differentiation in fish, as previously described for higher vertebrates. Our results suggest a parallel development between the vocal motor pathway and the peripheral auditory system for acoustic social communication in fish.
... Such evidence can be provided either by correlating sound energies at particular frequencies to auditory sensitivities or by showing unequivocal behavioural responses to sounds in the absence of visual stimuli. Despite a lack of information on the communicative value of sound production, numerous species from non-related taxa are known to vocalize in early (pre-reproductive) stages (Schneider 1964;Henglmüller and Ladich 1998;Amorim and Hawkins 2005;Kéver et al. 2012). This was typically observed during agonistic interactions such as fights over feeding items or feeding places. ...
... The onset of acoustic communication is still poorly investigated in fishes. Competition for resources such as food (and places) and predator defence are no doubt the main elements in the life of animals at all stages (Schneider 1964;Henglmüller and Ladich 1999;Amorim and Hawkins 2005;Bertucci et al. 2012). Such competition often results in aggressive behaviour, which probably always includes visual threat signals and frequently acoustic signals. ...
Chapter
Investigating the potential ability of juvenile fishes to communicate acoustically requires analysing the development of vocalization and hearing . To date, the ontogeny of both processes has been examined in three non-related species, namely the croaking gourami Trichopsis vittata (family Osphronemidae , order Perciformes), the squeaker catfish Synodontis schoutedeni (family Mochokidae , order Siluriformes) and the Lusitanian toadfish Halobatrachus didactylus (family Batrachoididae , order Batrachoidiformes). Juveniles of all three species vocalized during agonistic behaviour and showed similar changes in sound characteristics despite possessing different sonic mechanisms. With growth, dominant frequencies decreased, whereas sound pressure levels, pulse periods and sound duration (except in the toadfish) increased. Generally, hearing sensitivities improved during development, but differences were observed between species. Croaking gouramis of all stages responded to sounds up to 5 kHz. Auditory sensitivity increased in the high frequency range and the best hearing frequency shifted from 2.5 to 1.5 kHz. In the squeaker catfish, hearing abilities increased up to 2 kHz but showed a decrease at 5 and 6 kHz. The Lusitanian toadfish showed the smallest changes of all three species: the best hearing sensitivity was found at 50 Hz in all stages and hearing improved only at some frequencies. A comparison between audiograms and sound spectra within same-sized fish of the respective species revealed that the main energies of sounds were concentrated within the most sensitive frequencies. The comparison also showed that early-stage gouramis and toadfish probably cannot detect conspecific sounds due to low sound levels and high hearing thresholds . Only the catfish is able to communicate acoustically at all stages of development, most likely due to its Weberian apparatus .
... To remove the effect of the size, the features divided by the SL (written "X SL -1 " for the feature "X") were used instead of the features themselves. In fish, some sound features, such as pulse duration or fundamental frequency, are known to be affected by their body size [8,9,[51][52][53][54]. We combined our results with data also recorded in glass tanks from [55] and [10] to study the frequency as a function of size with 182 different specimens of red-bellied P. nattereri ranging from 44 to 270 mm (Fig 4). ...
Article
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The genus Pygocentrus contains three valid piranha species (P. cariba, P. nattereri and P. piraya) that are allopatric in tropical and subtropical freshwater environments of South America. This study uses acoustic features to differentiate the three species. Sounds were recorded in P. cariba, two populations of P. nattereri (red-and yellow-bellied) and P. piraya; providing sound description for the first time in P. cariba and P. piraya. Calls of P. cariba were distinct from all the other studied populations. Red-and yellow-bellied P. nattereri calls were different from each other but yellow-bellied P. nattereri calls were similar to those of P. piraya. These observations can be explained by considering that the studied specimens of yellow-bellied P. nattereri have been wrongly identified and are actually a sub-population of P. piraya. Morphological examinations and recent fish field recordings in the Araguari River strongly support our hypothesis. This study shows for the first time that sounds can be used to discover identification errors in the teleost taxa.
... This decrease of sound frequency has been found in several perciform, mormyrid, catfi sh and toadfi sh species (e.g. Ladich et al. 1992 ;Myrberg et al. 1993 ;Lobel and Mann 1995 ;Connaughton and Taylor 1996 ;Crawford 1997 ;Henglmüller and Ladich 1999 ;Wysocki and Ladich 2001 ;Amorim and Hawkins 2005 ;Vasconcelos and Ladich 2008 ;Parmentier et al. 2009 ;Colleye et al. 2009Colleye et al. , 2011Lechner et al. 2010 ;Bertucci et al. 2012 ), most studies additionally found increases in sound pressure level, total duration, and pulse periods of sounds with size of test specimens. ...
Chapter
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Abstract Numerous fish species are able to produce sounds and communicate acoustically. Nevertheless, hearing and sound production in fi shes is poorly understood and the ontogenetic development of acoustic communication has only been studied in a few species. So far the yellow marbled squeaker catfi sh Synodontis schoutedeni is the only species that has been shown to be able to communicate acoustically across generations at all postlarval stages of development. In two further fi sh species the smallest size groups were not yet able to detect sounds of equal conspecifi cs. Increasing body size in S. schoutedeni correlates with increasing hearing sensitivity for lower frequencies, decreasing hearing sensitivity at higher frequencies, increasing sound pressure level and duration of stridulation sounds, and decreases in stridulation sound dominant frequency. The excellent hearing sensitivities of S. schoutedeni , which are characteristic for Otophysi (fi sh with a Weberian apparatus), is probably the reason for their ability to communicate acoustically in early stages of development.
... In many species, the frequency of vocalizations reveals information on body size or mass (e.g. insects: Brown et al. 1996; fish: Ladich 1998; Amorim & Hawkings 2005; de Jong et al. 2007; anurans: reviewed in Searcy & Nowicki 2005; reptiles: Hibbitts et al. 2007; mammals: Pfefferle & Fischer 2006; but see also review in Searcy & Nowicki 2005; non-oscine birds: Guillotin & Jouventin 1980; Appleby & Redpath 1997; Barbaud et al. 2000; Miyasaki & Waas 2003; Madsen et al. 2004; Hardouin et al. 2007; Mager et al. 2007), despite the fact that individuals may, to some extent, vary the frequency of their vocalizations. The likely explanation is that, all else being equal, larger vocal organs and vocal tracts produce and radiate lowerfrequency sounds more efficiently than smaller ones (Bradbury & Vehrencamp 1998 ). ...
Article
Abstract Large animals, having large vocal organs, produce low sound frequencies more efficiently. Accordingly, the frequency of vocalizations is often negatively related to body size across species, and also among individuals of many species, including several non-oscine birds (non-songbirds). Little is known about whether song frequency reveals information about body size within oscine species, which are characterized by song learning and large repertoires. We asked whether song frequency is related to body size in two oscines that differ in repertoire size: the dark-eyed junco (Junco hyemalis) and the serin (Serinus serinus). We also asked whether the extent to which receivers sample repertoires might influence the reliability of their assessment of body size. We found that none of the frequency traits of song that we investigated was related to male body size, nor did more extensive sampling of repertoires lead to any relationship between frequency and body size. Possible reasons for these results are the small range of variation in size within species, or the elaborate vocal physiology of oscines that gives them great control over a wide frequency range. We discuss these results as they relate to female preferences for high-frequency song that have been previously reported for oscine species.
... Many teleosts are able to emit sounds associated with different behaviours such as feeding competition [1], courtship [2,3,4] or agonistic behaviour [5,6,7]. More precisely, sound production can be used to deter intruders [8,9,10], to identify conspecifics [11,12,13,14], or to attract and choose partners [15]. ...
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Background Sound production is widespread among fishes and accompanies many social interactions. The literature reports twenty-nine cichlid species known to produce sounds during aggressive and courtship displays, but the precise range in behavioural contexts is unclear. This study aims to describe the various Oreochromis niloticus behaviours that are associated with sound production in order to delimit the role of sound during different activities, including agonistic behaviours, pit activities, and reproduction and parental care by males and females of the species. Methodology/Principal Findings Sounds mostly occur during the day. The sounds recorded during this study accompany previously known behaviours, and no particular behaviour is systematically associated with sound production. Males and females make sounds during territorial defence but not during courtship and mating. Sounds support visual behaviours but are not used alone. During agonistic interactions, a calling Oreochromis niloticus does not bite after producing sounds, and more sounds are produced in defence of territory than for dominating individuals. Females produce sounds to defend eggs but not larvae. Conclusion/Significance Sounds are produced to reinforce visual behaviours. Moreover, comparisons with O. mossambicus indicate two sister species can differ in their use of sound, their acoustic characteristics, and the function of sound production. These findings support the role of sounds in differentiating species and promoting speciation. They also make clear that the association of sounds with specific life-cycle roles cannot be generalized to the entire taxa.
... In fish, temporal parameters are also known to change with fish size. Consistent with our results, both the grey gurnard (Eutrigla gurnardus) and the croaking gourami (Trichopsis vittata) show an increase of sound duration and pulse number in larger animals (Henglmüller & Ladich, 1999;Wysocki & Ladich, 2001;Amorim & Hawkins, 2005). Such temporal parameters are not as reliable as sound pressure level and dominant frequency to provide information on body size since they can be affected by the signaller's motivation. ...
Article
Many fish species emit sounds in agonistic contexts. During direct confrontations sounds are typically produced during the display phase in conjunction with visual exhibitions. Here we studied sound production during territorial defence in captive painted gobies, Pomatoschistus pictus, and related acoustic parameters with male traits and the date of recording (Julian day, i.e., with the approach of the peak of the breeding season). Territorial males emitted drumming sounds during displays that involved darkening the chin and fins, spreading fins and quivering the body. Drums were trains of low frequency pulses (≈23 pulses) repeated every 27 ms and usually lasting under a second. Drums were produced in short sequences of sounds (bursts). All acoustic parameters differed significantly among males. Drum and burst duration, and drum number of pulses increased significantly with male size. Calling duration (including drum, burst duration and drum number of pulses) also increased significantly with Julian date and presented a high intra-male variability, suggesting that these parameters may also depend on the individual's motivation. We provide the first report for agonistic sound production in sand gobies and give evidence that sound parameters contain information that can be used during mutual assessment in contests over territories.
... Sound of the type of grunts accompanying frontal demonstra tions signals about aggressive intentions of an individ ual emitting this sound Amorim et al., 2004b). With age, the aggressiveness in E. gurnardus decreases; therefore, larger individuals less frequently produce grunts and more frequently emit knocks (Amorim and Hawkins, 2005). Vocaliza tion related to feeding is typical also of other species of Triglidae-Prionotus carolinus and P. evolans (Fish, 1954). ...
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The paper lists basic data on the role of sounds in fish behavior. The involvement of acoustic signaling in the control of reproductive, territorial, agonistic, aggressive, social, and feeding behavior in fish that differ in the systematics and mode of life is considered. Species and population specifics and individual sound variation in fish, diurnal and seasonal cyclicity of sound activity, and behavior that accompany acoustic signaling and the effects upon it of different environmental factors are considered. Evidence on the formation of acoustic signaling in ontogenesis of fish is provided; the range of sound signaling and correspondence between sound spectra and auditory sensitivity are discussed. Possible applied aspects of results of study of fish bioacoustics are analyzed.
... The combination of terms acoustic and ontogeny is not normally associated with reflection of sound from fishes. Acoustic ontogeny is traditionally used to characterize hearing development and sound production in aquatic vertebrates such as fishes (Wysocki & Ladich, 2001;Amorim & Hawkins, 2005), seals (Charrier et al., 2001) and dolphins (McCowan & Reiss, 1995). In this study, (Wood, 2006a). ...
Article
The influence of growth on the intensity and variability of acoustic echoes from individuals and groups of a teleosts was quantified using Donaldson trout (rainbow–steelhead hybrid) Oncorhynchus mykiss. Fish growth was linear in total length (LT) and quadratic in mass. Dorsal swimbladder area increased exponentially with LT. Allometric growth ratio (i.e. k) values of swimbladder length linearly increased with LT. Average swimbladder volumes occupied 3–6% of fish body volume and increased exponentially with LT. The aspect angle that resulted in the maximum average acoustic intensity from the group shifted from 80 to 86° through the experimental period. Mean echo intensities increased at both 38 and 120 kHz as mean LT increased. Predicted echo intensities at 38 kHz exceeded that at 120 kHz at LT <150 mm but were less than that predicted at 120 kHz at LT >280 mm. Generalized additive mixed models using LT, swimbladder angles and lateral elongation ratios of fish bodies were better predictors of echo intensities than LT alone.
... Christie et al. 2004), social (e.g. Amorim and Almada 2005 ) or motivational status, ontogenic changes (e.g. Amorim and Hawkins 2005), physiological constraints or even individual identity (i.e. each individual's signal structure is consistent and unique; e.g. McGregor and Westby 1992). ...
Article
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We measured temporal and spatial components of the waving display in a Uca tangeri population to look for inter-individual differences in male waving structure that may convey information about individual identity. We found evidence that the spatial components of wave structure, especially “Maximum amplitude” are responsible for most of the between-male variation of the display. This variation could reflect differences in individuals’ condition and/or could be used by conspecifics to discriminate amongst familiar and unfamiliar individuals.
... Myrberg et al. (1993) found that just a small increase in the size of damselfish caused the signal frequency to decrease. Similarly, smaller grey gurnard produce higher frequency sounds than larger ones (Amorim and Hawkins 2005). ...
Article
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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.
... For example, sound pressure level increases and peak frequency decreases with body size in the grey weakfish, Cynoscion regalis (Connaughton et al. 2002), and similar findings were reported for two size classes in the grass goby, Zosterisessor ophiocephalus (Malavasi et al. 2003). In the grey gurnard, Eutrigla gurnardus, sound duration, pulse duration and the number of pulses increased, whereas the peak frequency decreased with fish size (Amorim & Hawkins 2005). Furthermore, in the bicolor damselfish, Pomacentrus partitus, females have been shown to prefer the sound of a larger male (Myrberg et al. 1986;McKibben & Bass 1998). ...
Article
Male calling or singing behaviour often plays a crucial role in competition among males and attraction of females. We studied the occurrence of male calls in a paternal nest-guarding fish, the rock-pool blenny. We found that males often produced calls when a female entered their nest burrow and during her visit inside the burrow. The dominant grunt-like part of these calls has a fundamental frequency of about 30 Hz and generally contains one to six harmonics. This harmonic component is typically preceded by a short introductory component and often followed by an even shorter terminal component, both of relatively low amplitude and irregular spectral composition. The fundamental frequency differs consistently between males and is negatively correlated with male size. Consequently, spectral features of the calls may be used in female mate choice during the female's decision to stay in a burrow and spawn. Not all males that were observed during a female visit produced calls, nor did calling males call during all female visits. The number of calls during a visit varied within and between males and ranged from 1 to 13. Calling may express some male mate preference when calls are selectively produced during visits of preferred large females. However, we did not find any evidence for differences in calling activity towards three female size classes, nor was there an effect of male size. This is one of the first reports in the literature on the use of sounds in blenny courtship behaviour and adds to a growing body of evidence revealing the communicative importance of acoustic signals in a wide variety of fish taxa.
... The most important insight was found at the level of the relationship between fish size and both dominant frequency and pulse duration. These kinds of relationships were already well known in fishes and have been found in numerous species from different taxa [26,27,[32][33][34][35][36]. In the present study and for the first time, it appears that these relationships are observed at a higher taxonomic level in the case of clownfishes (i.e. ...
Article
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Clownfishes are colorful coral reef fishes living in groups in association with sea anemones throughout the Indo-Pacific Ocean. Within their small societies, size hierarchy determines which fish have access to reproduction. These fishes are also prolific callers whose aggressive sounds seem to play an important role in the social hierarchy. Agonistic interactions being involved in daily behaviour suggest how acoustic communication might play an important role in clownfish group. Sounds were recorded and compared in fourteen clownfish species (some of which have never been recorded before) to evaluate the potential role of acoustic communication as an evolutionary driving force. Surprisingly, the relationship between fish size and both dominant frequency and pulse duration is not only species-specific; all the specimens of the 14 species are situated on exactly the same slope, which means the size of any Amphiprion can be predicted by both acoustic features. The number of pulses broadly overlaps among species, whereas the pulse period displays the most variation even if it shows overlap among sympatric species. Sound comparisons between three species (A. akallopisos, A. ocellaris and A. frenatus) having different types of teeth and body shape do not show differences neither in the acoustic waveform nor in the power spectrum. Significant overlap in acoustic features demonstrates that the sound-producing mechanism is highly conservative among species. Differences in the calls of some species are due to size dimorphism and the sound variation might be in this case a by-product. This morphological constraint does not permit a consideration of acoustic communication as the main driving force in the diversification of clownfishes. Moreover, calls are not produced to find mate and consequently are less subject to variations due to partner preference, which restricts the constraints of diversification. Calls are produced to reach and defend the competition to mate access. However, differences in the pulse period between cohabiting species show that, in some case, sounds can help to differentiate the species, to prevent competition between cohabiting species and to promote the diversification of taxa.
... Significant correlations between size and acoustic properties were observed in many soniferous fishes (e.g. Triglidae [58]; Mormyridae [59]; Osphronemidae [60]; Mochokidae [61]; Pomacentridae [62]; Batrachoididae [63]); and Gobiidae [64]). Nonetheless, P. septemradiatus is not an isolated exception: no correlation was found between body size and acoustic properties in either aggressive and courtship sounds also in the freshwater goby Padogobius bonelli [65], whose structural acoustic properties closely resemble those of P. septemradiatus. ...
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Coupled behavioural observations and acoustical recordings of aggressive dyadic contests showed that the mudskipper Periophthalmodon septemradiatus communicates acoustically while out of water. An analysis of intraspecific variability showed that specific acoustic components may act as tags for individual recognition, further supporting the sounds' communicative value. A correlative analysis amongst acoustical properties and video-acoustical recordings in slow-motion supported first hypotheses on the emission mechanism. Acoustic transmission through the wet exposed substrate was also discussed. These observations were used to support an "exaptation hypothesis", i.e. the maintenance of key adaptations during the first stages of water-to-land vertebrate eco-evolutionary transitions (based on eco-evolutionary and palaeontological considerations), through a comparative bioacoustic analysis of aquatic and semiterrestrial gobiid taxa. In fact, a remarkable similarity was found between mudskipper vocalisations and those emitted by gobioids and other soniferous benthonic fishes.
... In the croaking gourami Trichopsis vittata (Cuvier) for example, sound duration increases during ontogeny whereas dominant frequency decreases (Henglmüller & Ladich, 1999). In the grey gurnard Eutrigla gurnardus (L.), sound production changes from small juveniles to large adults during competitive feeding (Amorim & Hawkins, 2005). In catfishes (Siluriformes) (Fine & Ladich, 2003), weakfishes (Sciaenidae) (Connaughton et al., 2000), damselfishes (Pomacentridae) (Myrberg et al., 1993; Lobel & Mann, 1995), gouramis (Osphronemidae ) (Ladich et al., 1992) and pearlfishes (Carapidae) (Parmentier et al., 2006a), pulse duration increases and dominant frequency decreases in larger fishes. ...
Article
Fourteen individuals of the skunk clownfish Amphiprion akallopisos of different sizes and of different sexual status (non-breeder, male or female) were analysed for four acoustic features. Dominant frequency and pulse duration were highly correlated with standard length (r = 0.97), and were not related to sex. Both the dominant frequency and pulse duration were signals conveying information related to the size of the emitter, which implies that these sound characteristics could be useful in assessing size of conspecifics.
... Both species differed in pulse duration and dominant frequency but such differences need to be carefully interpreted because these sonic variables can be affected by fish size. The relationships between fish size and both pulse duration and dominant frequency have already been demonstrated for many soniferous fishes [28][29][30][31][32][33][34][35][36]. Moreover, Ladich [11] noticed that sounds produced by bigger males have lower main frequencies in the river bullhead C. gobio. ...
Article
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The freshwater sculpins (genus Cottus) are small, bottom-living fishes widely distributed in North America and Europe. The taxonomy of European species has remained unresolved for a long time due to the overlap of morphological characters. Sound production has already been documented in some cottid representatives, with sounds being involved in courtship and agonistic interactions. Although the movements associated with sound production have been observed, the underlying mechanism remains incomplete. Here, we focus on two closely related species from Belgium: C. rhenanus and C. perifretum. This study aims 1) to record and to compare acoustic communication in both species, 2) to give further insight into the sound-producing mechanism and 3) to look for new morphological traits allowing species differentiation. Both Cottus species produce multiple-pulsed agonistic sounds using a similar acoustic pattern: the first interpulse duration is always longer, making the first pulse unit distinct from the others. Recording sound production and hearing abilities showed a clear relationship between the sound spectra and auditory thresholds in both species: the peak frequencies of calls are around 150 Hz, which corresponds to their best hearing sensitivity. However, it appears that these fishes could not hear acoustic signals produced by conspecifics in their noisy habitat considering their hearing threshold expressed as sound pressure (~ 125 dB re 1 muPa). High-speed video recordings highlighted that each sound is produced during a complete back and forth movement of the pectoral girdle. Both Cottus species use an acoustic pattern that remained conserved during species diversification. Surprisingly, calls do not seem to have a communicative function. On the other hand, fish could detect substrate vibrations resulting from movements carried out during sound production. Similarities in temporal and spectral characteristics also suggest that both species share a common sound-producing mechanism, likely based on pectoral girdle vibrations. From a morphological point of view, only the shape of the spinelike scales covering the body allows species differentiation.
... Some teleosts are well known to emit sounds during various behaviours, such as feeding competition (Amorim and Hawkins, 2005), courtship (Lobel, 1998;Amorim et al., 2003) and agonistic behaviour (Ladich, 1997). These sounds are generally low-frequency (50-500Hz) pulses varying in duration, number and repetition rate (Winn, 1964;Amorim, 2006). ...
Article
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Although acoustic communication is an integral part of cichlid behaviour, its mechanism has never been identified before. In the present study, a combination of approaches was used to investigate the sound-producing mechanism of Oreochromis niloticus. Synchronisation of high-speed video data (500 frames s(-1)) and cineradiographies (250 frames s(-1)) with the sound recordings made it possible to locate the different body parts involved in sound production in territorial males. Sounds are made during a backward movement of the pelvic and pectoral girdles and a forward movement of the second pterygiophore of the anal fin. Various electrostimulation experiments, dissections and observation of histological cross-sections revealed a set of bundles (that we call the vesica longitudinalis) situated in the hypaxial musculature, ventro-laterally to the swimbladder. Contraction of these bundles should result in compression of the rib cage and also of the swimbladder, because of its close association with the serosa and ribs. Deflation of the swimbladder resulted in a reduced sound intensity.
... Vocalizations produced during direct aggressive interactions can also reflect body size and provide critical information to competing males. Acoustic properties of fish vocalizations during competitive feeding reflected the size of callers and could influence rates of agonism (Amorim and Hawkings, 2005). It is not known whether antipredator vocalizations also encode body size information. ...
Article
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Animals emit vocalizations that convey information about external events. Many of these vocalizations, including those emitted in response to predators, also encode information about the individual that produced the call. The relationship between acoustic features of antipredator calls and information relating to signalers (including sex, identity, body size, and social rank) were examined in peafowl (Pavo cristatus). The "bu-girk" antipredator calls of male and female peafowl were recorded and 20 acoustic parameters were automatically extracted from each call. Both the bu and girk elements of the antipredator call were individually distinctive and calls were classified to the correct signaler with over 90% and 70% accuracy in females and males, respectively. Females produced calls with a higher fundamental frequency (F0) than males. In both females and males, body size was negatively correlated with F0. In addition, peahen rank was related to the duration, end mean frequency, and start harmonicity of the bu element. Peafowl antipredator calls contain detailed information about the signaler and can potentially be used by receivers to respond to dangerous situations.
... Temporal characteristics of acoustic signals such as duration, number of bursts or pulses, and burst or pulse periods within sounds typically increase with size in all species studied (eg Amorim and Hawkins 2005;Connaughton et al. 2000;Colleye et al. 2009;Lechner et al. 2010;Tellechea et al. 2010;Knight and Ladich 2014;Hadjiaghai and Ladich 2015; 2 out of 8 piranha species: Mélotte et al. 2016). Exceptions include the toadfish H. didactylus, in which the number of pulses and thus sound duration decreased with growth (Vasconcelos and Ladich 2008). ...
Article
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Croaking gouramis (genus Trichopsis, Anabantoidei) generate series of two-pulsed bursts (croaks) during agonistic interactions. Sex-specific differences are minor in T. vittata which raises the question whether sexes differ in the other two species. The current study analyses sounds recorded in female T. schalleri, compares the sound characteristics to those of males investigated earlier and correlates these characteristics to female body size. Sex-specific differences were found in three out of six sound characteristics. In females, sounds were lower in burst number, burst period and SPL. Pulse period, dominant frequency and peak-to-peak amplitude ratios of pulses did not differ between sexes. Burst period and SPL increased significantly with female body weight, whereas dominant frequency decreased. The present acoustic data indicate the sex-specific differences are more pronounced in T. schalleri than T. vittata. The results also demonstrate that both sexes are vocal, which remains to be shown for females of the third species, T. pumila, which have poorly developed sonic organs. The evolution of the pectoral sound-producing mechanism in Trichopsis is most likely based on an exaptation process during which acoustic signals are generated by fin tendons initially related to other functions as is evident in closely related genera lacking this organ.
... Relationships between fish size and different acoustic characteristics have been shown in many species : sound level changes in a sciaenid (Connaughton et al., 2000) and in Forcipiger sp. (Boyle and Tricas, 2011), dominant frequency in most species studied (Amorim and Hawkins, 2005;Amorim et al., 2003;Bertucci et al., 2012;Colleye et al., 2011;Malavasi et al., 2003;Myrberg et al., 1993) and pulse duration in clownfish (Colleye et al., 2009(Colleye et al., , 2012 and Forcipiger sp. (Boyle and Tricas, 2011). ...
Article
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The ability to produce sounds has been known for decades in Balistidae. Sounds of many species have been recorded and a variety of sound producing mechanisms have been proposed including teeth stridulation, collision of buccal teeth, and movements of the fins. The best supported hypothesis involves movements of the pectoral fins against the lateral parts of the swimbladder called a drumming membrane. In this study, we describe for the first time the sounds made by the Blackbar triggerfish Rhinecanthus aculeatus that sound like short drum rolls with an average duration of 85 ms, 193 Hz dominant frequency and 136 dB SPL level at 3 cm distance. Sounds are a series of pulses that result from alternate sweeping movements of the right and left pectoral fins, which push a system of three scutes that are forced against the swimbladder wall. Pulses from each fin occur in consecutive pairs. High-speed videos indicate that each pulse consists in two cycles. The first part of each cycle corresponds to the inward buckling of the scutes whereas the second part of the cycle corresponds to an apparent passive recoil of the scutes and swimbladder wall. This novel sound production mechanism is likely found in many members of Balistidae because these peculiar scutes are found in other species in the family. Comparison of sound characteristics from fishes of different sizes shows that dominant frequency decreases with size in juveniles but not in adults.
... However, relatively small-sized paralichthyid fishes (\30 cm in maximum TL recorded) such as P. pentophthalmus in this study and Citharichthys spilopterus (see Guedes and Araújo 2008) fed more on benthic crustaceans than did other species. It is reasonable that diets of larger flounders should comprise more fish than those of smaller flounders, because body size gives an advantage in locating, capturing, and handling vertebrate prey items, i.e. teleosts (Amorim and Hawkins 2005). Although a high diversity of crustaceans was evident in our study area (Huh et al. 2010b), P. pentophthalmus usually consumed crangonid shrimps. ...
Article
The dietary habits and feeding strategy of Pseudorhombus pentophthalmus were studied based on 484 specimens collected from January to December 2006 off the southeastern coast of Korea. The total length (TL) of the specimens was 8.6–26.8 cm. P. pentophthalmus is a bottom-feeding carnivore that primarily consumes caridean shrimps and secondarily consumes teleosts, but also eats small amounts of crabs, cephalopods, mysids, euphausiids, stomatopods, amphipods, copepods, and isopods. The dietary compositions of P. pentophthalmus significantly differed between size groups during summer, but did not differ between size groups during other seasons, with caridean shrimps dominating the diet of both small and large groups in spring, autumn and winter. Permutational multivariate analysis of variance (PERMANOVA) and analysis of similarities (ANOSIM) revealed significant dietary differences by season, but not by size. Graphical analysis indicated that all size groups of P. pentophthalmus consumed mainly caridean shrimps during all seasons, but teleosts were only important during summer.
... Biomass may have specific characteristics linked to the size distribution of fishes and the distinctive sounds produced by fish of various sizes within a species (e.g. Amorim and Hawkins, 2005). As large fishes may fulfil important roles for coral reef functioning (Bascompte et al., 2005;Lokranz et al., 2008) and are known to be highly vulnerable (e.g. ...
Thesis
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Les récifs coralliens sont l’écosystème marin le plus complexe, mais aussi le plus menacé par les perturbations croissantes liées aux activités anthropiques. Leur conservation représente un véritable défi. Alors que le maintien des récifs au plus proche de leurs configurations et dynamiques actuelles doit être privilégié, nous devons également nous préparer à une évolution rapide de leur fonctionnement et adapter réseaux et outils de suivis à cette nouvelle situation. Des avancées technologiques récentes ont permis l’émergence d’outils innovants qui pourraient permettre à court terme d’augmenter considérablement la résolution spatio-temporelle des suivis. Parmi eux, l’acoustique passive est en plein essor. L’objet de cette thèse a été d’affiner son cadre d’utilisation pour évaluer et suivre l’état écologique et le fonctionnement des écosystèmes coralliens. Des enregistrements des paysages sonores et des relevés écologiques (assemblages de poissons et habitat) ont été réalisés sur 31 récifs de pente externe autour de trois îles de l’Indo-pacifique avec des caractéristiques environnementales variables, incluant des pressions anthropiques contrastées. L’analyse des résultats obtenus avec différentes combinaisons de paramètres d’échantillonnage (bande de fréquences, moment du cycle journalier choisi pour réaliser l’enregistrement, durée des échantillons de son) a permis de sélectionner un protocole d’échantillonnage basé sur les deux types d’indices écoacoustiques les plus utilisés pour l’étude des récifs coralliens. Ce protocole permet la caractérisation rapide et fiable de l’état écologique des récifs. En se basant sur ces lignes directrices, la capacité de six indices écoacoustiques à évaluer des fonctions clé de l’écosystème corallien a ensuite été démontrée. En comparant les apports de l’acoustique passive et de données environnementales pouvant être collectées par télédétection, la plus-value de l’utilisation d’indices écoacoustiques pour prédire la structure des assemblages de poissons récifaux a été identifiée et quantifiée. Une application de l’approche écoacoustique au suivi continu d’un site isolé a mis en évidence le potentiel particulièrement important de l’acoustique passive comme outil d’appui à la gestion dans ce type de contexte. Face à l’ampleur et à la vitesse des changements climatiques annoncés, les méthodes de suivi employées aujourd’hui, basées sur la présence d’observateur in situ, seront vraisemblablement insuffisantes. Combinée à d’autres outils de suivi, l’acoustique passive pourrait contribuer à détecter rapidement les perturbations des écosystèmes, condition indispensable pour en comprendre les causes et mettre en œuvre des réponses rapides et adaptées.
... For example, sound pressure level increases and peak frequency decreases with body size in the grey weakfish, Cynoscion regalis (Connaughton et al. 2002), and similar findings were reported for two size classes in the grass goby, Zosterisessor ophiocephalus (Malavasi et al. 2003). In the grey gurnard, Eutrigla gurnardus, sound duration, pulse duration and the number of pulses increased, whereas the peak frequency decreased with fish size (Amorim & Hawkins 2005). Furthermore, in the bicolor damselfish, Pomacentrus partitus, females have been shown to prefer the sound of a larger male (Myrberg et al. 1986;McKibben & Bass 1998). ...
... The common species are: shanny (Lipophyrys pholis), tompot blenny (Parablennius gattorugine), Montagu's blenny (Coryphoblennius galerita) and the red blenny (Parablennius ruber). Amorim et al. (2004) and Amorim and Hawkins (2005) described sound production and usage by the grey gurnard (Eutrigla gurnadus). The sound consisted of a series of pulse trains described as knocks or grunts with each pulse containing energy up to 1700 Hz. ...
Thesis
This study investigated a clicking sound which is often heard when deploying a hydrophone in UK shallow waters. This sound has often been described as being produced by snapping shrimp yet very few snapping shrimp have been found in UK waters. This work has identified the sound of snapping shrimp and shown that a similar sound, while present throughout the year, is not the dominant component of the click field during the summer and autumn. This work has shown that the click sounds are heard in the southern half of the UK only and that click activity has a strong dependence on the annual and diurnal cycles peaking in late summer and during daylight hours. It has also shown that the click activity is dependent on the bottom type with little activity over uniform sand or mud sea beds. Three principal types of click have been identified although it is believed that a greater number of different species contribute to the click field. Localisation of the click sources using one, two and four hydrophone arrays has shown that the majority of the clicks are produced above but close to the seabed. There is also more click activity in the deeper channel than in the inter-tidal shallows at the main study site in the Fleet, Dorset. It has also demonstrated very little click activity over the nearby sand flats. The use of cameras to try and capture pictures of an animal producing the clicks both in the wild and in aquaria and in rock pools has not been successful. This may be due to a number of reasons which are discussed in this report. Although this work has failed to identify the click-producing species it has provided a much better understanding of the characteristics of the clicking sound and recommendations are made for future work that should lead to an identification of the click-producing species.
... Similarly, sound production during competitive feeding changes from small juvenile grey gurnards (E. gurnardus) to large adults (Amorim and Hawkins, 2005), with smaller fish being more active sound producers than larger and presenting significant differences in some sound features. Sound duration, pulse duration and number of pulses increased while peak frequency decreased with fish size in knocks and grunts. ...
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Fish sound characteristics are associated with different sound-generating mechanisms. Sounds produced by swimbladder-related mechanisms usually comprise low-frequency pulses produced at different rates. Fishes emit one to five sound types that do not show such outstanding variability as found in other taxa. However, closely related species show consistent differences in their sounds and in some species even individuality is found. Of particular interest are differences in courtship sounds made by closely related sympatric species that may promote reproductive isolation. Differences between individuals of the same species may in turn play a role in sexual selection through male-male competition and female mate choice. Other known sources of variability are related to context, including motivation and recent social status, season, time of day, ontogenetic changes and sexual dimorphism. Fish sound variability is mainly based on temporal patterning of sounds or pulses within a sound and on frequency variation (sometimes modulation). Such variability has been found to play a role in the social life of fishes.
... Relationships between fish size and different acoustic characteristics have been shown in many species : sound level changes in a sciaenid (Connaughton et al., 2000) and in Forcipiger sp. (Boyle and Tricas, 2011), dominant frequency in most species studied (Amorim and Hawkins, 2005;Amorim et al., 2003;Bertucci et al., 2012;Colleye et al., 2011;Malavasi et al., 2003;Myrberg et al., 1993) and pulse duration in clownfish (Colleye et al., 2009(Colleye et al., , 2012 and Forcipiger sp. (Boyle and Tricas, 2011). ...
... La production de sons, bien qu‗également peu abondante, montre que l'aptitude à émettre des signaux sonores apparaît très tôt chez M. zebra, avant que le répertoire comportemental tel qu'observé chez les adultes ne soit complètement observable. Chez T. vittata, la production de sons apparait lors de la huitième semaine de vie, après les poursuites ou les displays latéraux qui sont présents dès la troisième semaine alors que les comportements les plus agressifs comme les morsures sont observés lors de la dixième semaine ) ou E. gurnardus (Amorim & Hawkins, 2005). En ce qui concerne l'ontogenèse de la structure acoustique des signaux émis, les enregistrements réalisés montrent que les premières productions consistent en des pulses isolés, dont la fréquence instantanée diminue avec la croissance en taille des poissons. ...
Thesis
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Various species of fish are known to produce sounds in different social contexts suggesting an important communicative role of acoustic signals. The aim of this thesis is to study the structure and the function of sounds produced during aggressive interactions between males of the cichlid fish Metriaclima zebra. By means of playback experiments, the relative role of acoustic and visual cues during agonistic interactions is evaluated. The results show that aggressive behaviour is essentially based on visual stimuli. Acoustic stimuli alone never trigger aggression but modulate males' behavior by decreasing the high level of aggressiveness found when only the visual channel is present. A fine analysis of the structure of sounds produced during disputes shows that signals emitted by M. zebra encode information related to the size of the emitter. The individual signature remains poorly defined. In order to understand the decoding process of information by receivers, I set up a paradigm allowing to show that territorial males increase their territorial activity and approach loudspeakers in response to playbacks. Playback experiments using signals with artificially modified acoustic parameters suggest a large tolerance for temporal variations. This thesis thus participates to the comprehension of the biological function of acoustic communication in a fish. It calls for further studies concerning the transmitted information and its encoding process
... Biomass may have specific characteristics linked to the size distribution of fishes and the distinctive sounds produced by fish of various sizes within a species (e.g. Amorim and Hawkins, 2005). As large fishes may fulfil important roles for coral reef functioning (Bascompte et al., 2005;Lokrantz et al., 2008) and are known to be highly vulnerable (e.g. ...
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The functioning of tropical coral reefs is imperilled by climate change, overfishing, and decreasing water quality. Maintaining their capacity to provide goods and services will critically depend on our ability to monitor their functioning at appropriate spatial and temporal scales. Given the constraints of traditional methods to respond to those needs, the potential of complementary tools such as Passive Acoustic Monitoring (PAM) is emerging. Coral reef soundscapes (i.e. ambient sound) encompass sounds produced by numerous organisms. Soundscape characteristics quantified by ecoacoustic indices have been found to reflect general ecosystem properties, such as diversity and abundance of fishes, and coral cover. The present study tested, on the virtually pristine coral reefs around Europa Island, SouthWest Indian Ocean, the capacity of acoustic indices to assess key ecosystem functions. Soundscapes were recorded during 2 h, and ecosystem functions were evaluated using video footage of the fish assemblages and underwater photogrammetry of the benthic landscapes. We found significant and strong correlations between six ecoacoustic indices and six key ecosystem functions, including habitat features and fish assemblage characteristics. The six ecoacoustic indices were representative of several combinations of frequency, amplitude and time analysis domains, highlighting the diversity of the functional information conveyed by soundscapes. Our findings reveal that a 2 h daytime recording on a coral reef could provide sufficient acoustic information to characterise major ecosystem functions of a site. This should facilitate the detection of functional disturbances at temporal and spatial scales adapted to the rapidity of upcoming climate changes. Our results also highlight the potential of ecoacoustics to bring novel and relevant insights in the functioning of ecosystems.
... Biomass may have specific characteristics linked to the size distribution of fishes and the distinctive sounds produced by fish of various sizes within a species (e.g. Amorim and Hawkins, 2005). As large fishes may fulfil important roles for coral reef functioning (Bascompte et al., 2005;Lokranz et al., 2008) and are known to be highly vulnerable (e.g. ...
Thesis
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Coral reefs are the most complex of marine ecosystems, but also the most threatened by ecological disruption resulting directly or indirectly from human activities. Their conservation represents a huge challenge. While maintaining coral reefs as close as possible to their current configurations and dynamics is among the highest priorities, we must also prepare for rapid changes in their functioning and adapt monitoring tools and networks to this new situation. Recent technological advances enabled the emergence of innovative tools with the potential to drastically increase the spatio-temporal resolution of coral reef monitoring. Among these, Passive Acoustic Monitoring (PAM) is on the rise. The aim of this thesis was to improve and facilitate the use of PAM as a tool for the assessment and monitoring of coral reefs’ ecological states and functioning. Soundscape recordings and ecological surveys (reef fish assemblages and habitat) were performed at 31 outer reef slope sites around three Indo-Pacific islands with variable environmental characteristics, including contrasted anthropogenic pressures. Analysing the results obtained with multiple combinations of sampling settings (frequency bandwidth, time of sampling (day/night), and sample duration) allowed the selection of a sampling scheme based on the two types of indices mostly used in coral reef studies. This scheme enables a rapid and reliable categorisation of reef’s ecological states. Based on these sampling guidelines, the capacity of six ecoacoustic indices to evaluate coral reef key functions was demonstrated. By comparing the contributions of PAM and coarse environmental data that could be sampled remotely, the added value of using ecoacoustic indices to predict reef fish assemblage structure was identified and quantified. An application of ecoacoustics to the continuous monitoring of a remote site highlighted the strong potential of PAM as a supporting tool for managers in such context. In view of the amplitude and velocity of expected climatic changes, current observer-based monitoring methods are likely to be exceeded. Combined to other monitoring tools, PAM could contribute to promptly detect ecosystem disturbances, which is essential to understand their causes and put in place rapid and adapted responses.
... Larger fish tend to produce lower-frequency (e.g. Ladich, 1998;Myrberg et al., 1993;Lobel and Mann, 1995;Connaughton et al., 2000), louder (Ladich, 1998;Connaughton et al., 2000;Lindström and Lugli, 2000;Amorim et al., 2013) and longer sounds (Wysocki and Ladich, 2001;Amorim and Hawkins, 2005;Amorim and Neves, 2008) than smaller individuals. Also, the level of calling activity may reflect the amount of fat reserves (Amorim et al., 2010aPedroso et al., 2013). ...
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The function of fish sounds in territorial defence, in particular its influence on the intruder's behaviour during territorial invasions, is poorly known. Breeding Lusitanian toadfish males (Halobatrachus didactylus) use sounds (boatwhistles) to defend nests from intruders. Results from a previous study suggest that boatwhistles function as a 'keep-out signal' during territorial defence. To test this hypothesis we performed territorial intrusion experiments with muted Lusitanian toadfish. Subject males were assigned to three groups: muted, sham and unmanipulated. Males were muted by making a cut and deflating the swimbladder (the sound producing apparatus) under anaesthesia. Sham males suffered the same surgical procedure except the swimbladder cut and deflation. Toadfish nest-holder males reacted to intruders mainly by emitting sounds (sham and unmanipulated) and less frequently with escalated fights. When the nest-holder produced a boatwhistle, the intruder fled more frequently than expected by chance alone. Muted males experienced a higher number of intrusions than the remaining groups probably due to their inability to vocalise. Together, our results show that fish acoustic signals are effective deterrents in nest/territorial intrusions, similar to bird song.
... A large number of fishes are known to produce sounds in different social contexts such as agonistic interactions, courtship and competitive feeding (Amorim et al., 2003;Amorim and Hawkins, 2005;Amorim and Neves, 2008;Bertucci et al., 2010;Colleye and Parmentier, 2012;Ladich, 1997;Lobel, 1998;Longrie et al., 2013;Parmentier et al., 2010). Sounds produced by males during courtship interactions for instance can affect the choice of female mate (Amorim et al., 2004;Danley et al., 2012;Phillips and Johnston, 2009;Verzijden et al., 2010). ...
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Grunts are fish that are well known to vocalize, but how they produce their grunting sounds has not been clearly identified. In addition to characterizing acoustic signals and hearing in the French grunt Haemulon flavolineatum, the present study investigates the sound-production mechanism of this species by means of high-speed X-ray videos and scanning electron microscopy of the pharyngeal jaw apparatus. Vocalizations consist of a series of stridulatory sounds: grunts lasting ~47 ms with a mean period of 155 ms and a dominant frequency of ~700 Hz. Auditory capacity was determined to range from 100 to 600 Hz, with greatest sensitivity at 300 Hz (105.0±11.8 dB re. 1 μPa). This suggests that hearing is not tuned exclusively to detect the sounds of conspecifics. High-speed X-ray videos revealed how pharyngeal jaws move during sound production. Traces of erosion on teeth in the fourth ceratobranchial arch suggest that they are also involved in sound production. The similarity of motor patterns of the upper and lower pharyngeal jaws between food processing and sound production indicates that calling is an exaptation of the food-processing mechanism.
... Dominant frequency of stridulation sounds decreased with increasing body size across species (standard length and body mass). The same trend was already described in representatives of numerous fish families such as in callichthyids, mochokids, gurnards, mormyrids, croaking gouramis, damselfish and toadfish (Ladich et al., 1992;Myrberg et al., 1993;Crawford, 1997;Pruzsinszky and Ladich, 1998;Henglmüller and Ladich, 1999;Wysocki and Ladich, 2001;Amorim and Hawkins, 2005;Vasconcelos and Ladich, 2008;Lechner et al., 2010;Parmentier et al., 2010). Ladich (Ladich, 1997) found such a correlation in one out of two doradid species, namely in P. armatulus but not in A. pectinifrons, which might have been due to the small size range in the previous study. ...
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Thorny catfishes produce stridulation sounds (SR) using their pectoral fins and drumming sounds (DR) via swimbladder mechanism in distress situations when hand-held in water and in air. Ladich (1997) argued that SR and DR are aimed at different receivers (predators) in different media. The aim of this study was to analyse sounds, compare characteristics of sounds emitted in both media in order to test different hypotheses on the functional significance of distress sounds. Five representatives of the family Doradidae were investigated. Fish were hand-held and sounds emitted in air and underwater were recorded. The following sound characteristics were analyzed - number of sounds, sound duration, dominant and fundamental frequency, sound pressure level and peak-to-peak amplitudes - and compared between media. All species produced SR and DR in both media except for two species in which DR could not be recorded in air. Differences in sound characteristics between media were small and mainly limited to spectral differences in SR. Number of sounds emitted decreased over time while SR sound duration increased. Dominant frequency of SR and fundamental frequency of DR decreased and sound pressure level of SR increased with body size across species. The hypothesis that catfish produce more SR in air and more DR in water due to different predation pressure (birds versus fish) could not be confirmed. It is assumed that SR serve as distress sounds in both media, whereas DR might primarily be used as intraspecific communication signals in water in species possessing both mechanisms.
... The peak frequency of such sounds decreases rapidly with fish size, whereas sounds evoked by just a sonic muscle and swimbladder change gradually or not at all with fish size [19,56]. Minor changes in frequency can be mediated by larger muscles that take longer to contract [21] or by larger swimbladders that will be more effective than smaller ones at coupling low frequency sounds into water [57,58]. Therefore, they are not explicit evidence of swimbladder resonance. ...
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Despite rapid damping, fish swimbladders have been modelled as underwater resonant bubbles. Recent data suggest that swimbladders of soundproducing fishes use a forced rather than a resonant response to produce sound. The reason for this discrepancy has not been formally addressed, and we demonstrate, for the first time, that the structure of the swimbladder wall will affect vibratory behaviour. Using the oyster toadfish Opsanus tau, we find regional differences in bladder thickness, directionality of collagen layers (anisotropic bladder wall structure), material properties that differ between circular and longitudinal directions (stress, strain and Young’s modulus), high water content (80%) of the bladder wall and a 300-fold increase in the modulus of dried tissue. Therefore, the swimbladder wall is a viscoelastic structure that serves to damp vibrations and impart directionality, preventing the expression of resonance. © 2016 The Author(s) Published by the Royal Society. All rights reserved.
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Soundscapes provide a new tool for the study of fish communities. Bigeyes (Pempheris adspersa) are nocturnal planktivorous reef fish, feed in loose shoals and are soniferous. These vocalisations have been suggested to be contact calls to maintain group cohesion, however direct evidence for this is absent, despite the fact that contact calls are well documented for many other vertebrates, including marine mammals. For fish, direct evidence for group cohesion signals is restricted to the use of visual and hydrodynamic cues. In support of adding vocalisation as a contributing cue, our laboratory experiments show that bigeyes significantly increased group cohesion when exposed to recordings of ambient reef sound at higher sound levels while also decreasing vocalisations. These patterns of behaviour are consistent with acoustic masking. When exposed to playback of conspecific vocalisations, the group cohesion and vocalisation rates of bigeyes both significantly increased. These results provide the first direct experimental support for the hypotheses that vocalisations are used as contact calls to maintain group cohesion in fishes, making fish the evolutionarily oldest vertebrate group in which this phenomenon has been observed, and adding a new dimension to the interpretation of nocturnal reef soundscapes.
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It was recently demonstrated that clownfishes produce aggressive sounds by snapping their jaw teeth. To date, only the onset of the sound has been studied, which raises the question, what structure is involved in sound radiation? Here, a combination of different approaches has been used to determine the anatomical structure(s) responsible for the size-related variations observed in sound duration and frequency. Filling the swimbladder with physiological liquid specifically modified size-related acoustic features by inducing a significant decrease in pulse duration of approximately 3 ms and a significant increase in dominant frequency of approximately 105 Hz. However, testing the acoustics of the swimbladder by striking it with a piezoelectric impact hammer showed that this structure is a highly damped sound source prevented from prolonged vibrations. In contrast, the resonant properties of the rib cage seems to account for the size-related variations observed in acoustic features. For an equivalent strike on the rib cage, the duration and dominant frequency of induced sounds changed with fish size: sound duration and dominant frequency were positively and negatively correlated with fish size, respectively. Such relationships between sonic features and fish size are consistent with those observed in natural sounds emitted by fish. Therefore, the swimbladder itself does not act as a resonator; its wall just seems to be driven by the oscillations of the rib cage. This set of observations suggests the need for reassessment of the acoustic role of swimbladders in various fish species.
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Chapter
Fish represent the largest group of vertebrates and display the greatest diversity of auditory structures. However, studies addressing how the form and function of the auditory system change during development to enhance perception of the acoustic environment are rather sparse in this taxon compared to other vertebrate groups. An ontogenetic perspective of the auditory system in fishes provides a readily testable framework for understanding structure–function relationships. Additionally, studying ancestral models such as fish can convey valuable comparable information across vertebrates, as early developmental events are often evolutionary conserved. This chapter reviews the literature on the morphological development of the fish auditory system, with particular focus on the inner ear structures that evolve from an otic placode during early embryonic development and then continue to undergo differentiation and maturation in the postembryonic phase. Moreover, the chapter provides a systematic overview of how auditory sensitivity develops during ontogeny. Although most studies indicate a developmental improvement in auditory sensitivity, there is considerably species-specific variation. Lastly, the paucity of information and literature concerning the development of auditory capabilities for social communication in fishes is also discussed. Further investigation on the development of structure and function of the fish auditory system is recommended in order to obtain a deeper understanding of how ontogenetic morphological changes in the auditory pathway relate to modifications in acoustic reception, auditory processing, and the capacity to communicate acoustically.
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Most passive acoustics studies focus on daily and seasonal timing and location of choruses of calling fish, particularly sciaenids. Because male toadfish Opsanus spp. are stationary for extended periods, it is possible to extract detailed information about their calls and interactions, making them a powerful model for passive acoustics studies on commercially important species. Toadfishes of both sexes produce a short, pulsatile agonistic grunt, and males produce a “boatwhistle” advertisement call for male-male competition and to attract females. We identify unseen vocal individuals (oyster toadfish O. tau and Gulf toadfish O. beta) near a stationary hydrophone and describe call variability and changes over short- and long-term periods, source levels, call propagation, and directionality. Calls exhibit a directional pattern related to the heart-shaped swim bladder morphology, generating a maximal level behind the fish; grunt frequency spectra allow differentiation of individual callers over multiweek periods. Boatwhistle parameters of oyster toadfish calls change geographically, seasonally, and with temperature, and males call day and night. The Gulf toadfish call rate increases during twilight, when individuals produce shorter and simpler calls. Finally, nearby calling males compete acoustically by increasing their calling rates or producing a grunt (an acoustic tag) during another male's boatwhistle. Toadfishes have been successful models for addressing numerous questions in unseen fish by means of passive acoustics.
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An extremely wide variety of fish taxa produce sound. Sound production behavior provides an opportunity to study various aspects of fish biology, such as spawning behavior and habitat selection, in a noninvasive manner. Passive acoustics is an active area of ichthyological research. However, fish bioacousticians have generally not published their research in the fisheries literature. Therefore, fisheries scientists may not be fully aware of progress being made in this field or of potential uses for passive acoustic techniques. In this paper, I discuss the evolutionary, physiological, and behavioral aspects of sound production by fishes; investigate the publication patterns of research on fish sound production; review the literature on the application of passive acoustic methods to fisheries research; and suggest ways of designing passive acoustic surveys to optimize the quantity and quality of information obtained. Passive acoustic methods can be an attractive alternative or supplement to traditional fisheries assessment techniques because they are noninvasive, can be conducted at low cost, and can cover a large study area at high spatial and temporal resolution. However, as in all fisheries surveys, research questions should be defined clearly at the outset and careful planning is necessary to obtain the data required to address those questions.
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The streaked gurnard Trigloporus lastoviza produced only one sound type, a growl, lasting up to 3 s and consisting of repeated groups of typically one to three pulses. The foraging fish followed two different strategies. In the first, the fish circled the feeding area, grasped a food item and fled, sometimes displaying aggressively to competitors. With this foraging strategy, fish usually made sounds as they circled, grasped and fled. Fish that growled while circling were more likely to grasp a food item subsequently than were silent fish. The second feeding strategy occurred when a fish had already ingested food or failed to get any. In this case, typically fish searched for food on the substratum or approached and touched other individuals that were feeding, sometimes grabbing food that was spat out during food handling by the other fish. Although payback experiments would be needed to draw firm conclusions on the communicative function of growling during competitive feeding in the streaked gurnard, the results suggest that sound production confers advantages Co individuals competing for limited food resources. (C) 2000 The Fisheries Society of the British Isles.
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A foraging model was developed to predict the optimal diet breadth and maximum energetic intake of a given-sized fish foraging in each of three aquatic habitats: the open water, vegetation, and bare sediments. Model parameters of prey encounter rates and prey handling times were quantified as functions of fish size, prey density, and prey size through a series of laboratory feeding experiments using the bluegill sunfish (Lepomis macrochirus). Results of these experiments show both searching ability and prey handling efficiency to increase with increasing fish size. Predictions of prey size selection and optimal habitat use based upon maximizing energetic gain were then examined in a small Michigan lake for three size classes of bluegills. Bluegills > 100 mm standard length were highly size selective in their feeding and their diets closely matched predictions of an optimal diet model. From two estimates of relative prey visibilities I show that these fish selected larger prey items than would be predicted if prey were consumed "as encountered." Habitat use of large bluegills was also shown to maximize foraging return as fish switched from utilizing vegetation-living prey to utilizing open-water zooplankton as relative foraging profitabilities in the two habitats changed across the summer. Bluegills
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Previous work has shown that neurons in the sonic motor nucleus of the oyster toadfish, Opsanus tau, grow larger in males than in females and increase in size and number for 7–8 years. In order to correlate postnatal motoneuron development with growth of target muscle fibers, we examined the ontogeny of sonic muscle growth. Both the swim bladder and attached sonic muscles increased in size for life and were, respectively, 20 and 44% larger in males than in females. The muscle and swim bladder grew at an equivalent rate in males, whereas in females, muscle growth did not keep up with bladder growth. The number of muscle fibers increased about 16-fold (31 000 to 488 000), and mean minimum fiber diameter increased almost 3-fold (11.5 to 28.6 μm) as fish grew. Fibers were 15.3% larger in females than in males (adjusted means of 21.9 and 19.0 μm, respectively), but males had 47% more fibers per muscle (adjusted means of 307 000 and 209 000). Muscle fibers also exhibited morphological changes. Most of the fibers in two juveniles had yet to differentiate the core of sarcoplasm characteristic of sonic muscle, whereas the largest cells in mature males and females tended to have multiple pockets of sarcoplasm and a contractile cylinder split into fragments. Multiple pockets in large fibers and the presence of smaller fibers in males than females are interpreted as adaptations for increased speed and fatigue resistance.
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The juveniles of several species of freshwater fish search for zooplankton prey using a strategy intermediate between cruise and ambush: "saltatory search" (SS) or "pause–travel" search. Unlike ambush or cruise search, saltatory search involves scanning for prey throughout the search space and only during the brief stationary periods that punctuate repositioning movements. If no prey are located, these fish swim a short distance, stop, and scan again. In this paper, we describe the ontogeny of prey search in a cyprinid, the golden shiner (Notemigonus crysoleucas), a species whose search pattern has not been examined. Swimming and pursuit speeds and prey location distances increased with fish size. Golden shiner larvae searched for prey throughout the search space and only during the pauses that punctuated swimming movements. Only 1–10% of all of the stationary pauses that punctuated swimming movements were followed by attacks on prey. We conclude that golden shiner larvae employ a saltatory-search strategy similar to that described in other zooplanktivorous fish and their larvae.
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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.
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The spatial and temporal clumping of food influence an animal's aggressiveness during competition. No studies, however, have investigated the effects of the temporal predictability of food and few studies have tested for interactions between the effects of two components of resource distribution on the rates of competitive aggression. We simultaneously manipulated the temporal predictability and the spatial clumping of food to test whether aggression increases as food becomes more predictable in time and more clumped in space. We tested these predictions using wild Zenaida doves ( Zenaida aurita ) in Barbados because previous work showed marked differences in social behavior between two populations, apparently related to differences in the distribution of food in space and time. There was a significant interaction between the effects of the temporal predictability and spatial clumping of food. As predicted, the rate of aggression increased as the temporal predictability of food increased, but only significantly in the spatially clumped condition. Similarly, as predicted, aggression increased as the spatial clumping of food increased, but only significantly in the temporally predictable condition. In addition, the per capita rate of aggression peaked at intermediate competitor densities in the spatially clumped condition. Differences in rates of aggression observed during experimental manipulations and between the two populations during baseline observations were generally consistent with predictions of resource defense theory.
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This study documents the development of inter- and intrasexual dimorphisms in the vocal ('sonic') muscles of the swimbladder in the plainfin midshipman fish, Porichthys notatus. Midshipman have two male reproductive morphs, Types I and II. Only Type I males build nests and generate mate calls to attract females; Type II males sneak or satellite spawn. Vocal muscles in the mate-calling Type I males were 25-fold larger in absolute size (sixfold larger when scaled to body size) compared with females or non-calling Type II males. Dimorphisms in muscle mass were correlated with dimorphisms in fiber number and diameter. Only nascent Type I males experienced a pre-maturational, fourfold increase of fiber number followed by a rapid, fivefold increase in fiber cross-sectional area at sexual maturity. Also specific to Type I males was a striking change in cell structure: the ratio of sarcoplasm to myofibril area increased fivefold. By contrast, Type II males and females matured without showing any of these changes in sonic muscle--the trajectories which described juvenile growth continued to hold through maturity and adulthood. The results indicate distinct, non-sequential, ontogenetic trajectories for Type I and Type II males. The origin of the Type II male morphotype is described as paedomorphosis by progenesis: size distributions of free-living animals suggest that Type II males can mature precocially as one-year-old fish, whereas Type I males defer reproduction until they are at least two years of age.
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We present the first analysis of scaling effects on the motor pattern of a feeding vertebrate. Data are presented for the effects of body size on the pattern of activity in four head muscles during prey capture in the largemouth bass, Micropterus salmoides. Electromyographic (EMG) recordings were made from three expansive-phase muscles (the epaxialis, the sternohyoideus and the levator arcus palatini) and one compressive-phase muscle (the adductor mandibulae), during the capture of small fish prey. Recordings were made of 181 prey-capture events from 19 bass that ranged in size from 83 to 289 mm standard length. We measured seven variables from the myogram of each capture to quantify the temporal pattern of muscle activation, including the duration of activity in each muscle and the onset time of each muscle, relative to the onset of the sternohyoideus muscle. Regressions of the mean value of each variable for the 19 individuals on standard length revealed that only the onset time of the adductor mandibulae changed with fish body size. The increase in onset time of the adductor muscle appears to reflect the longer time taken to open the mouth fully in larger fish. Other research shows that the kinematics of the strike in this species slows significantly with increasing body size. The combined results indicate that the duration of the EMG signal is not directly correlated with the duration of force production in muscles when compared between fish of different sizes. The lack of scaling of burst duration variables suggests that the reduced speeds of prey-capture motion are explained not by changes in the envelope of muscle activity, but rather by the effects of scale on muscle contractile kinetics. These scaling effects may include changes in the relative resistance of the jaw and head structures to movement through water and changes in the intrinsic contractile properties of the muscles of the feeding apparatus.
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To categorize variation in disturbance calls of the weakfish Cynoscion regalis and to understand their generation, we recorded sounds produced by different-sized fish, and by similar-sized fish at different temperatures, as well as muscle electromyograms. Single, simultaneous twitches of the bilateral sonic muscles produce a single sound pulse consisting of a two- to three-cycle acoustic waveform. Typical disturbance calls at 18 degrees C consist of trains of 2-15 pulses with a sound pressure level (SPL) of 74 dB re 20 microPa at 10 cm, a peak frequency of 540 Hz, a repetition rate of 20 Hz and a pulse duration of 3.5 ms. The pulse duration suggests an incredibly short twitch time. Sound pressure level (SPL) and pulse duration increase and dominant frequency decreases in larger fish, whereas SPL, repetition rate and dominant frequency increase and pulse duration decreases with increasing temperature. The dominant frequency is inversely related to pulse duration and appears to be determined by the duration of muscle contraction. We suggest that the lower dominant frequency of larger fish is caused by a longer pulse (=longer muscle twitch) and not by the lower resonant frequency of a larger swimbladder.
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The streaked gurnard Trigloporus lastoviza produced only one sound type, a growl, lasting up to 3 s and consisting of repeated groups of typically one to three pulses. The foraging fish followed two different strategies. In the first, the fish circled the feeding area, grasped a food item and fled, sometimes displaying aggressively to competitors. With this foraging strategy, fish usually made sounds as they circled, grasped and fled. Fish that growled while circling were more likely to grasp a food item subsequently than were silent fish. The second feeding strategy occurred when a fish had already ingested food or failed to get any. In this case, typically fish searched for food on the substratum or approached and touched other individuals that were feeding, sometimes grabbing food that was spat out during food handling by the other fish. Although payback experiments would be needed to draw firm conclusions on the communicative function of growling during competitive feeding in the streaked gurnard, the results suggest that sound production confers advantages to individuals competing for limited food resources.
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HAT are the conditions which facilitate or hinder the evolution of ter- ritoriality? No generally accepted solution to this problem has yet been found-perhaps because too specific an answer has been sought for too general a question. Instead, the diversity of systems of territorial and other aggressive behavior has come to be well appreciated, as evidenced in recent reviews of territoriality (e.g., Kuroda, 1960; Carpenter, 1953; Hinde, 1956), and the impossibility of providin g a specific answer applicable to all types of territoriality is now realized. Arguments over which are the primary selection pressures leading to cer- tain types of territoriality continue, however, as shown in the recent contribu- tions bearing on the "function" of territoriality by Stenger (1958)) Wynne- Edwards (1962), Kalela (1958)) Kuroda (1960), Peters (1962)) and others. The present paper offers a new orientation to the problem by presenting a general theory for the evolution of territoriality with special reference to its diversity among species. Since most of the previous theories have already been shown to be untenable or severely limited (see especially Carpenter, 1958; Tinbergen, 1957; and Hinde, 1956, for criticism of them), little attention will be given to them here. A theoretical framework for the consideration of some of the mechanisms promoting and limiting the evolution of territorial behavior is outlined in Fig. 1. Aggressive behavior is generally employed by individuals in the acquisition of goals which tend to maximize individual survival and reproduction. Natu- ral selection should favor aggressive behavior within a population when these goals are consistently and easily accessible to individuals through aggression but should not favor it when they are not accessible. For example, when a food supply cannot be feasibly defended, because of its mobility or transient nature , generally no territorial system is evolved to defend it; and the terri- tory, if present, may be restricted only to the nest and the area reachable by the parents on the nest. Such cases are found in colonial sea birds, nomadic and social feeding passerine species, and aerial feeders. In these species the goal of increased or guaranteed food supply is unlikely to be attained through aggression. On the other hand, if the individual depends for its nesting requirements,
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The acoustic repertoire of captive grey gurnard Eutrigla gurnardus during competitive feeding consisted of three types of sound: knocks, grunts and growls. Knocks were audible as a single sound, whereas grunts and growls were perceived as longer, pulsed sounds to the human ear. Typically, knocks were composed of 1–2 pulses, grunts of 4–8 pulses and growls >10 pulses. Growls were longer and had shorter pulse periods than grunts. All sound types had peak frequencies of c. 500 Hz. The sequences of behaviours observed during feeding interactions suggest that grey gurnard obtain food both by scramble and contest tactics. Competing fish emitted knocks mainly while grasping a food item and also during other non-agonistic behav-iour, suggesting that knock production may reflect a state of feeding arousal but could also serve as a warning of the forager's presence to nearby competitors. Grunts were mainly emitted during frontal displays, which were the most frequent behavioural act preceding grasps, suggesting that they may play a role in deterring other fish from gaining access to disputed food items.
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In four scatter-fed groups of Tilapia rendalli, the distribution of food between individuals was not significantly different from that expected if the food was shared uniformly between all the fish in the group for nine of the 12 radiographic assessments of feeding behaviour. Individual fish maintained the same feeding rank over time, indicating a stable feeding hierarchy, in only one of the four scatter feeding groups. In contrast, in four point source feeding groups, the distribution of food between individuals differed significantly from uniformity in 10 of the 12 radiographic assessments of feeding behaviour and stable feeding hierarchies were maintained over time in three of the four groups. Thus, scatter feeding promoted a more uniform distribution of food between individuals within the group and prevented the formation of feeding hierarchies. There was no significant correlation between individual feeding rank and dominance index in all four scatter feeding groups. In contrast, significant positive correlations were found between individual feeding rank and dominance index in all four point source feeding groups. The results of this study confirm that feeding rank can be used as a correlate of relative social status under defensible feeding conditions.
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The degree of monopolization of resources is thought to be higher in groups that compete by interference than by exploitation. However, the monopolization of resources will presumably depend on (1) whether the dispersion of resources is economically defendable, and (2) whether some competitors have the ability to defend these resource distributions and hence capitalize on this potential. We tested for an interaction between the effects of temporal resource dispersion and aggressiveness on the degree of resource monopolization in a foraging system. Two species of fish differing markedly in aggressiveness (high: convict cichlids, Archocentrus nigrofasciatus; low: goldfish, Carrasius auratus) were allowed to compete intra-specifically in groups of four for food that was either potentially defendable (arrived asynchronously) or not (arrived synchronously). As predicted, the monopolization of food, measured as the coefficient of variation of food eaten within groups, was significantly higher in the defendable than in the undefendable treatment for convict cichlids but not for goldfish. However, the monopolization of food was higher in the non-aggressive goldfish than in the aggressive convict cichlids. Future studies should quantify and compare the monopolization in species that compete primarily via scramble competition to those that use primarily resource defence.
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The role of sound production of the Mozambique tilapia Oreochromis mossambicus in agonistic and mating interactions observed during hierarchy formation and in established groups was examined. Only territorial males produced sounds, during male–female and male–male courtship interactions and during pit-related activities (e.g. dig, hover and still in the nest). Sound production rate was positively correlated with courting rate. Although sounds in other cichlids are typically emitted in early stages of courtship, O. mossambicus produced sounds in all phases, but especially during late stages of courtship, including spawning. It is suggested that the acoustic emissions in this species may play a role in advertising the presence and spawning readiness of males and in synchronizing gamete release.
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Although juvenile chum salmon,Oncorhynchus keta, are generally regarded as a schooling fish, when presented with a defensible point-source of food, some individuals abandon schooling, aggressively subordinate competitors, and monopolize food. When food is removed, fish gradually abandon solitary agonistic behaviors and return to schooling behavior. Agonism increases in frequency and intensity as juveniles age. The ability to alternate facultatively between schooling and solitary agonistic behavior may enable juvenile chum to respond to local patterns of food distribution and predation risk. The ontogenetic increase in agonism may result in school dispersal as fish move from the estuary into coastal waters, and may well reflect a shift in the costs versus the benefits of schooling as fish mature and become less vulnerable to predation.
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Optimality models designed to explain the occurrence of feeding territoriality predict that the frequency or intensity of aggression will peak at intermediate levels of food abundance. To test whether this prediction applies to the competition for ephemeral patches of food, we manipulated food abundance over a broad range of values in two separate experiments (24- and 64-fold, respectively) while monitoring the aggressive behaviour of juvenile convict cichlids,Archocentrus nigrofasciatum , competing for the food. In both experiments, the rate of aggression was low when food was scarce, increased as food abundance increased, and decreased when food was provided in excess. This dome-shaped pattern of aggression was caused partly by higher encounter rates between fish and partly by a higher proportion of encounters resulting in aggression, when food was at intermediate levels of abundance. Our results suggest that convict cichlids display behavioural flexibility: in response to changes in food abundance, they appear to change both their likelihood of using aggression when encountering a conspecific and their willingness to enter an occupied patch.
Article
Three testosterone (T) implant experiments were carried out to investigate the hormonal control of seasonal hypertrophy in the sound producing, or sonic, muscles of the weakfish Cynoscion regalis. The first experiment examined the role of T in the seasonal increase in sonic muscle mass noted in adult male weakfish during the spring and summer spawning period. Specimens held over-winter were implanted with T or vehicle prior to the natural spawning season. The sonic muscle mass of the T-implanted group increased two and a half-fold over a period of 3 weeks, while that of the sham-implanted group did not change. At the end of the experiment, the cross-sectional area of the sonic muscle fibers in the T-implanted group averaged 500 microns 2, while that of the sham-implanted group averaged 300 microns 2. In a second experiment, the elevated sonic muscle mass of spawning male weakfish was sustained with pharmacological levels of plasma T for a period of 4 months following the spawning season. The sonic muscle mass of the sham-implanted group decreased to typical postseason values. In a third experiment, male and female age-0 weakfish were held over-winter and then implanted with T in advance of their first natural spawning season. The sonic muscles of the T-treated male specimens attained twice the mass of those of the sham-implanted male specimens in 3 weeks time. No sonic muscle development was noted in any of the female specimens.
Article
The anabantoid fish Trichopsis vittata starts vocalizing as 8-week-old juveniles. In order to determine whether juveniles are able to detect conspecific sounds, hearing sensitivities were measured in six size groups utilizing the auditory brainstem response-recording technique. Results were compared to sound pressure levels and spectra of sounds recorded during fighting. Auditory evoked potentials were present in all size groups and complete audiograms were obtained starting with 0.18 to 0.30 g juveniles. Auditory sensitivity during development primarily increased between 0.8 kHz and 3.0 kHz. The most sensitive frequency within this range shifted from 2.5 kHz to 1.5 kHz, whereas thresholds decreased by 14 dB. Sound production, on the other hand, started at 0.1 g and sound power spectra at dominant frequencies increased by 43 dB, while dominant frequencies shifted from 3 kHz to 1.5 kHz. Comparisons between audiograms and sound power spectra in similar-sized juveniles revealed no clear match between most sensitive frequencies and dominant frequencies of sounds. This also revealed that juveniles cannot detect conspecific sounds below the 0.31 to 0.65 g size class. These results indicate that auditory sensitivity develops prior to the ability to vocalize and that vocalization occurs prior to the ability to communicate acoustically.
Underwater sound and fish behaviour Distribution and abundance of grey gurnard (Eutrigla gurnardus) in the North Sea
  • A D Hawkins
  • T J Pitcher
Hawkins, A. D. 1993: Underwater sound and fish behaviour. In: Behaviour of Teleost Fishes (Pitcher, T. J., ed.). Chapman & Hall, London, pp. 129—169. M. C. P. Amorim & A. D. Hawkins Heesen, H. J. L. & Daan, N. 1994: Distribution and abundance of grey gurnard (Eutrigla gurnardus) in the North Sea. ICES CM 1994/O3.
Growth of grey gurnard Eutrigla gurnardus L. in the North Sea
  • U Damn
Damn, U. 1987: Growth of grey gurnard Eutrigla gurnardus L. in the North Sea. International Council for the Exploration of the Sea (ICES), Council Meeting (CM), Copenhagen 1987/G55.
Distribution and abundance of grey gurnard (Eutrigla gurnardus) in the North Sea. ICES CM
  • H J L Heesen
  • N Daan
Heesen, H. J. L. & Daan, N. 1994: Distribution and abundance of grey gurnard (Eutrigla gurnardus) in the North Sea. ICES CM 1994/O3.