Is the Tonal Quality of Birdsong Learned? Evidence from Song Sparrows

Song sparrow (Melospiza melodia) songs are composed largely of pure-tonal sounds. This paper investigates the role that learning plays in the development of the tonal structure of song sparrow songs, as well as the role that tonal quality plays in determining the suitability of songs as models for learning. 20 birds were trained with both normal pure-tonal songs and modified songs that included harmonic overtones. The harmonic-modified songs were obtained from birds singing in a helium atmosphere, the result of which is to perturb vocal tract resonances and thus alter a song's tonal quality. Subjects learned equally well from normal and harmonic models. Birds that learned material from harmonic models reproduced some of this material with harmonic overtones, but the majority of notes learned from harmonic models were subsequently reproduced as pure-tonal copies. Thus, the tonal structure of songs does not influence young song sparrows in their selection of song models, but there is a strong tendency to reproduce songs in a pure-tonal fashion, even if learned from harmonic models.     

Sexual differences in cricket calling song recognition

Summary Phonotactic behavior was studied in male crickets,Teleogryllus oceanicus. Tethered flying males were presented with electronically synthesized calling song models in a two-choice phonotaxis assay, and their song preferences were determined and compared with previous findings for females.Males are poorer at discriminating between songs than females; they do not display choice behavior as frequently as females, and the choices they do make are not as consistent as those of females (Figs. 3, 4). T. oceanicus calling song is composed of rhythmically different chirp and trill sections. The selectivity of males for these two components differs from that of females. Females prefer chirp to trill, but the opposite is true for males (Fig. 5B-F). Males are similar to females in that they prefer either a conspecific song model or its separate components to a heterospecific model (Fig. 5A, G, H).Behavioral and neural implications of these findings are discussed.     

Development of Tonal Quality in Birdsong: Further Evidence from Song Sparrows

Song sparrow (Melospiza melodia) songs are composed largely of pure-tone notes. Song sparrows raised in acoustic isolation (i.e. never hearing conspecific songs) tend to produce half of their notes with harmonic overtones, an atypical tonal structure, suggesting that exposure to pure tones is necessary for the development of normal tonal quality. The experiment presented here directly investigated the influence of early exposure to songs with different tonal qualities on subsequent production. Seven young song sparrow males were exposed to 16 normal, pure-tone song sparrow songs and 6 males were exposed to the same 16 song types with added harmonic overtones. Birds in both groups learned equally well, confirming an earlier finding that tonal quality does not influence selection of models during the sensitive period for song acquisition. Birds exposed exclusively to harmonic song models, however, produced over 85% of their learned notes in a pure-tone fashion, even though they had never heard pure-tone sounds. Thus, pure tones do not need to be experienced directly by song sparrows, but exposure to some features of species-typical song models appears to facilitate the reproduction of models in a pure-tone fashion.     

Frequency and temporal pattern-dependent phonotaxis of crickets (Teleogryllus oceanicus) during tethered flight and compensated walking

Summary Phonotactic responses ofTeleogryllus oceanicus were studied with two methods. Tethered crickets were stimulated with sound while they performed stationary flight, and steering responses were indicated by abdominal movements. Walking crickets tracked a sound source while their translational movements were compensated by a spherical treadmill, and their walking direction and velocity were recorded.During both flight and walking, crickets attempted to locomote towards the sound source when a song model with 5 kHz carrier frequency was broadcast (positive phonotactic response) and away from the source when a song model with 33 kHz carrier frequency was used (negative phonotactic response) (Figs. 2, 4).One-eared crickets attempted, while flying, to steer towards the side of the remaining ear when stimulated with the 5 kHz model, and away from that side in response to the 33 kHz model (Fig. 3). While walking, one-eared crickets circled towards and away from the intact side in response to the 5 kHz and 33 kHz models, respectively (Fig. 6).Positive and negative responses differed in their temporal pattern requirements. Phonotactic responses were not elicited when a non-calling song pattern (2 pulses/s) was played with a carrier frequency appropriate for positive phonotactic responses (5 kHz), but this pattern did elicit negative responses with 33 kHz carrier frequency (Figs. 7–10). When an intermediate carrier frequency, 15 kHz, was used, the response type (positive or negative) depended on the stimulus temporal pattern; the calling song pattern elicited primarily positive responses, while the non-calling song pattern elicited negative responses (Figs. 11, 12, 14, 15). A curious phenomenon was often observed in the flight steering responses; while most responses to 15 kHz song pattern were primarily positive, they often had an initial negative component which was supplanted by the positive component of the response after approximately 2–5 s (Figs. 11, 12).In recent experiments onGryllus campestris, Thorson et al. (1982) described frequency-dependent errors in phonotactic direction (anomalous phonotaxis) and showed how such errors might arise from the frequency-dependent directional properties of the cricket's auditory apparatus. Our findings, particularly the dependence of response type on temporal pattern when 15 kHz carrier frequency was used, argue that frequency-dependent directional properties alone cannot account for positive and negative phonotaxis inT. oceanicus. Rather, these represent qualitatively different attempts to locomote towards and away from the sound source, respectively.We discuss the possibility that central integration of these opposing tendencies might contribute to anomalous phonotaxis.     

Phonotaxis in flying crickets

The steering responses of three species of field crickets, Teleogryllus oceanicus, T. commodus, and Gryllus bimaculatus, were characterized during tethered flight using single tone-pulses (rather than model calling song) presented at carrier frequencies from 3-100 kHz. This range of frequencies encompasses the natural songs of crickets (4-20 kHz, Fig. 1) as well as the echolocation cries of insectivorous bats (12-100 kHz). The single-pulse stimulus paradigm was necessary to assess the aversive nature of high carrier frequencies without introducing complications due to the attractive properties of repeated pulse stimuli such as model calling songs. Unlike the natural calling song, single tone-pulses were not attractive and did not elicit positive phonotactic steering even when presented at the calling song carrier frequency (Figs. 2, 3, and 9). In addition to temporal pattern, phonotactic steering was sensitive to carrier frequency as well as sound intensity. Three discrete flight steering behaviors positive phonotaxis, negative phonotaxis and evasion, were elicited by appropriate combinations of frequency, temporal pattern and sound intensity (Fig. 12). Positive phonotactic steering required a model calling song temporal pattern, was tuned to 5 kHz and was restricted to frequencies below 9 kHz. Negative phonotactic steering, similar to the 'early warning' bat-avoidance behavior of moths, was produced by low intensity (55 dB SPL) tone-pulses at frequencies between 12 and 100 kHz (Figs. 2, 3, and 9). In contrast to model calling song, single tone-pulses of high intensity 5-10 kHz elicited negative phonotactic steering; low intensity ultrasound (20-100 kHz) produced only negative phonotactic steering, regardless of pulse repetition pattern. 'Evasive', side-to-side steering, similar to the 'last-chance' bat-evasion behavior of moths was produced in response to high intensity (greater than 90 dB) ultrasound (20-100 kHz). Since the demonstration of negative phonotactic steering did not require the use of a calling song temporal pattern, avoidance of ultrasound cannot be the result of systematic errors in localizing an inherently attractive stimulus when presented at high carrier frequencies. Unlike attraction to model calling song, the ultrasound-mediated steering responses were of short latency (25-35 ms) and were produced in an open loop manner (Fig. 4), both properties of escape behaviors.(ABSTRACT TRUNCATED AT 400 WORDS)     

历山自然保护区四种蟋蟀鸣声结构的比较研究(直翅目:蟋蟀总科)

应用计算机技术,分析了山西历山自然保护区的白须双针蟋,短翅灶蟋,银川油葫芦,迷卡斗蟋4种蟋蟀雄性的鸣声结构,白须双针蟋雄性鸣声的每个脉冲组持续时间和每个脉冲组的脉冲数不同,主能峰频率为6．5kHz,短翅灶蟋雄性鸣声的时域波形较规则,每个脉冲组由3个脉冲构成,每个脉冲组的持续时间,脉冲组间隔基本相同,主能峰频率6．6kHz,银川油葫芦雄性的鸣声由两类脉冲组构成,主能峰频率为3．94kHz,迷卡斗蟋雄性鸣声的时域波形较规则,每个脉冲组由6－7个脉冲构成,主能峰频率为3．86kHz。     

Frequency as a releaser in the courtship song of two crickets,Gryllus bimaculatus (de Geer) and Teleogryllus oceanicus: a neuroethological analysis

1. The courtship behavior of male field crickets, Gryllus bimaculatus (De Geer) and Teleogryllus oceanicus, is a complex, multimodal behavioral act that involves acoustic signals (a courtship song; Fig. 1A,B). The dominant frequency is 4.5 kHz for T. oceanicus song (Fig. 1A) and 13.5 kHz for G. bimaculatus (Fig. IB).
2. When courting males are deprived of their courtship song by wing amputation, their courtship success declines markedly but is restored when courting is accompanied by tape-recordings of their courtship songs or a synthetic courtship song with only the dominant frequency of the natural song; other naturally occurring frequency components are ineffective for restoring mating success (Figs. 4, 5).
3. It has been suggested that an identified auditory interneuron, AN2, plays a critical role in courtship success. Chronic recordings of AN2 in an intact, tethered female show that AN2's response to the natural courtship song and synthesized songs at 4.5 and 13.5 kHz is similar in T. oceanicus. By contrast, in G. bimaculatus, AN2's response to the natural courtship song and synthesized song at 13.5 kHz, but not at 4.5 kHz, is similar (Figs. 2,3).
4. In behavioral experiments, playback of a 30 kHz synthetic courtship song in G. bimaculatus does not restore courtship success, yet this same stimulus elicits as strong a response from AN2 as does the normal courtship song (Fig. 6). Thus, contrary to earlier work by others, we conclude AN2 is not, by itself, a critical neural link in the courtship behavior of these two species of crickets.

     

Acoustic signals in insects: A reproductive barrier and a taxonomic character

In singing insects, the song is an important component of the specific mate recognition system (SMRS). In communities of sympatric singing species, there is a partitioning of communication channels, the so-called “acoustic niches.” Within one community, the songs of different species always differ in temporal or frequency characters, i.e. occupy different acoustic niches. However, conspecific songs do not always act as an interspecific reproductive barrier, despite always being a SMRS component. The species that do not communicate acoustically due to allopatry, different timing of vocalization, inhabiting different biotopes, or unmatched food specializations can produce similar songs while forming reproductively isolated communities. Individuals of different sexes need not only to recognize a conspecific mate but also to evaluate its “quality.” The close-range signal (courtship song) provides more opportunities for choosing the “best” male than does the distant signal (calling song). In many species of Orthoptera, courtship includes not only acoustic but also vibrational, visual, chemical, and mechanical signals. An analysis of cricket songs showed the courtship songs to be on average more elaborate and variable than the calling songs. At the same time, due to the difference in mating behavior between the two groups, the acoustic component of courtship is used for mate quality evaluation to a greater extent in grasshoppers than in crickets. The courtship songs of grasshoppers are generally more elaborate in temporal structure than cricket songs; moreover, they may be accompanied by visual displays such as movements of various body parts. Thus, song evolution in grasshoppers is more strongly driven by sexual selection than that in crickets. According to the reinforcement hypothesis, the premating barrier between hybridizing species becomes stronger in response to reduced hybrid fitness. However, our behavioral experiments with two groups of hybridizing grasshopper species did not confirm the reinforcement hypothesis. We explain this, firstly, by a low level of genetic incompatibility between the hybridizing species and secondly, by high hybrid fitness when attracting a mate. A high competitive capability of hybrids may be accounted for by attractiveness of new elements in hybrid courtship songs. When we divide similar forms based on their songs, we in fact distinguish biological species using the criterion of their reproductive isolation. Acoustic differences between species are usually greater than morphological ones. Therefore, song analysis allows one to determine the real status of doubtful species-rank taxa, to distinguish species in a medley of sibling forms, and to reveal cryptic species in the cases when morphological studies fail to provide a univocal result. At the same time, songs are subject to intraspecific variation the range of which is different in different groups. Therefore, it is necessary to study which degree of difference corresponds to the species level before interpreting the status of some forms based on song comparisons. Besides, song similarities cannot indicate conspecificity of acoustically isolated forms; on the other hand, song differences between these forms prove that they are full-rank species.     

Ultrasonic singing by the blue-throated hummingbird: a comparison between production and perception

Blue-throated hummingbirds produce elaborate songs extending into the ultrasonic frequency range, up to 30 kHz. Ultrasonic song elements include harmonics and extensions of audible notes, non-harmonic components of audible syllables, and sounds produced at frequencies above 20 kHz without corresponding hearing range sound. To determine whether ultrasonic song elements function in intraspecific communication, we tested the hearing range of male and female blue-throated hummingbirds. We measured auditory thresholds for tone pips ranging from 1 kHz to 50 kHz using auditory brainstem responses. Neither male nor female blue-throated hummingbirds appear to be able to hear above 7 kHz. No auditory brainstem responses could be detected between 8 and 50 kHz at 90 dB. This high-frequency cutoff is well within the range reported for other species of birds. These results suggest that high-frequency song elements are not used in intraspecific communication. We propose that the restricted hummingbird hearing range may exemplify a phylogenetic constraint.     

THE COMMUNICATIVE SIGNIFICANCE OF TONALITY IN BIRDSONG: RESPONSES TO SONGS PRODUCED IN HELIUM

ABSTRACT

“Pure tones” are a distinctive acoustic feature of many birdsongs. Recent research on songbird vocal physiology suggests that such tonal sounds result from a coordinated interaction between the syrinx and a vocal filter, as demonstrated by the emergence of harmonic overtones when a bird sings in helium. To investigate the communicative significance of vocal tract filtration in the production of birdsong, we used field playback experiments to compare the responses of male swamp sparrows Melospiza georgiana to normal songs and those same songs recorded in helium. We also measured responses to pure tone songs that had been shifted upward in frequency to match the average spectra of those songs with added harmonics. Male sparrows were significantly more responsive to the playback of normal songs than to either helium songs with added harmonics or frequency- shifted pure tone songs. Songs with harmonics retained a high degree of salience, however. We conclude that explanations for the occurrence of tonal sounds in birdsongs must consider perceptual attributes of songs as communicative signals, as well as problems of song production and transmission.     

The effect of ultrasound on the attractiveness of acoustic mating signals

Abstract. Previous laboratory studies ( Nolen & Hoy 1986b ) have shown that the phonotactic responses of flying crickets are influenced by the relative intensities of attractive (mating signal) and repulsive (predator) stimuli. At the functional level, these results suggest that predator cues (ultrasound) can change the attractiveness of a calling song. Using extracellular recordings from cervical connectives it was shown that, like other field crickets, Gryllus rubens (south-eastern field cricket) is sensitive to ultrasound. This ultrasonic sensitivity has probably evolved in response to predation pressure from echolocating bats. Using acoustic playback under field conditions, it was tested whether the relative attractiveness of two male calling songs was influenced by the simultaneous broadcast of ultrasound. A simulated male calling song of G. rubens was broadcast at two different intensities (109 and 103 dB) from two sound traps that caught flying crickets attracted to the songs. Simulated bat ultrasound was broadcast simultaneously with the high-intensity calling song (109 dB) and the relative catch in each of the two traps was measured. The intensity of the ultrasound was varied on different nights. The relative attractiveness of the high-intensity sound trap decreased significantly as the intensity of the ultrasound broadcast with it was increased. For the lowest of the ultrasound broadcast levels, the relative attractiveness did not differ from that expected for two calling songs broadcast without ultrasound. Thus, increased levels of simulated predation risk decreased the attractiveness of the calling song associated with it. These are the first field experiments to show that predation risk in the form of simulated bat ultrasound influences the phonotactic behaviour of flying crickets.     

No Effect of Body Size on the Frequency of Calling and Courtship Song in the Two-Spotted Cricket,Gryllus bimaculatus

The relationship between body size and vocalization parameters has been studied in many animal species. In insect species, however, the effect of body size on song frequency has remained unclear. Here we analyzed the effect of body size on the frequency spectra of mating songs produced by the two-spotted cricket, Gryllus bimaculatus. We recorded the calling songs and courtship songs of male crickets of different body sizes. The calling songs contained a frequency component that peaked at 5.7 kHz. On the other hand, courtship songs contained two frequency components that peaked at 5.8 and 14.7 kHz. The dominant frequency of each component in both the calling and courtship songs was constant regardless of body size. The size of the harp and mirror regions in the cricket forewings, which are the acoustic sources of the songs, correlated positively with body size. These findings suggest that the frequency contents of both the calling and courtship songs of the cricket are unaffected by whole body, harp, or mirror size.     

Low-frequency airborne vibrations generated by crickets during singing and aggression

When crickets (Gryllus bimaculatus) produce their calling, courtship and rivalry songs, they generate, in addition to the audible stridulatory sound, low-frequency air oscillations associated with the inward and outward movements of the forewings. The frequencies of these oscillations are below ca 70 Hz, with a major component at 30 Hz, the syllable repetition rate. In the courtship song, single oscillations are also produced. Jerking movements of the whole body, which often occur in the presence of rivals, cause considerable air currents. In all these cases the air vibrations are sufficient to be perceived both by the individual generating them and by conspecifics (and perhaps by other insects) via air-flow receptors, in crickets the cercal filiform hairs.     

Phonotaxis in flying crickets

The effects of two-tone stimuli on the high frequency bat-avoidance steering behavior of flying crickets (Teleogryllus oceanicus) were studied during tethered flight. Similarly, the effects of two-tone stimuli on the ultrasound sensitive auditory interneuron, Int-1, which elicits this behavior, were studied using intracellular staining and recording techniques. When a low frequency tone (3-8 kHz) was presented simultaneously with an aversive high frequency tone (in a two-tone stimulus paradigm), the high frequency avoidance steering behavior was suppressed. Suppression was optimal when the low frequency tone was between 4 and 5 kHz and about 10-15 dB louder than the high frequency tone (Figs. 2, 3). Best suppression occurred when the low frequency tone-pulse just preceded or overlapped the high frequency tone-pulse, indicating that the suppressive effects of 5 kHz could last for up to 70 ms (Fig. 4). The threshold for avoidance of the bat-like stimulus was elevated when model bat biosonar (30 kHz) was presented while the animal was performing positive phonotaxis toward 5 kHz model calling song, but only if the calling song intensity was relatively high (greater than 70-80 dB SPL) (Fig. 1). However, avoidance steering could always be elicited as long as the calling song was not more than 10 dB louder than the ultrasound (Fig. 1). This suppressive effect did not require performance of positive phonotaxis to the calling song (Fig. 2) and was probably due to the persistence of the suppressive effects of the 5 kHz model calling song (Fig. 4). The requirement for relatively high intensities of calling song suggest that the suppression of bat-avoidance by the calling song is not likely to be of great significance in nature. The high frequency harmonics of the male cricket's natural calling song overlap the lower frequency range used by insectivorous bats (10-20 kHz) and are loud enough to elicit avoidance behavior in a flying female as she closely approaches a singing male (Fig. 5). The high frequency 'harmonics' of a model calling song were aversive even if presented with a normally attractive temporal pattern (pulse repetition rate of 16 pps) (Fig. 6A). When the 5 kHz 'fundamental' was added to one of the high frequency 'harmonics', in a two-tone stimulus paradigm, this complex model calling song was attractive; the high frequency 'harmonic' no longer elicited the avoidance behavior (Fig. 6) and the animals steered toward the model CS. Thus, addition of 5 kHz to a high frequency harmonic of the calling song 'masked' the aversive nature of this stimulus.(ABSTRACT TRUNCATED AT 400 WORDS)     

Vibrational communication and mating behaviour of Dichelops melacanthus (Hemiptera: Pentatomidae) recorded from loudspeaker membranes and plants

Vibrational communication is important for successful mating in various stink bugs species. The vibrational signals from males and females of Dichelops melacanthus Dallas (Hemiptera: Pentatomidae) are recorded from a nonresonant substrate (i.e. a loudspeaker membrane) to characterize the temporal and spectral properties of these vibrational signals, as well as on a resonant substrate (i.e. bean plants) to obtain information about how these signals are altered when they are transmitted through the plants. On the loudspeaker membrane, D. melacanthus males and females emit only one male or one female song, respectively. However, when the insects are placed on bean leaves, a more complex repertoire is recorded, with three different songs for each sex. The first female and male songs appear to have calling functions and the third male and female songs are emitted during courtship. The second female and male songs are emitted after the first song, although their functions in mating behaviour are not clear. The identified repertoire is similar to those of other Neotropical stink bugs, starting with songs 1 and 2 and developing into song 3. Frequency modulation is observed in the female songs recorded from the loudspeaker membrane and the plants. The signals recorded from plants present higher harmonic peaks compared with the signals recorded from the loudspeaker membrane. The presence of species and sex‐specific songs during mating confirms the important role of vibrational communication in mate location and recognition. The temporal and spectral characteristic signals are influenced by the substrate used to record the songs emitted by D. melacanthus.     

Divergent Preferences for Song Structure between a Field Cricket and its Phonotactic Parasitoid

In many animals, males produce signals to attract females for mating. However, eavesdropping parasites may exploit these conspicuous signals to find their hosts. In these instances, the strength and direction of natural and sexual selection substantially influence song evolution. Male variable field crickets, Gryllus lineaticeps, produce chirped songs to attract mates. The eavesdropping parasitoid fly Ormia ochracea uses cricket songs to find its hosts. We tested female preferences for song structure (i.e., chirped song vs. trilled song) in crickets and flies using choice experiments. Female crickets from a parasitized and a non-parasitized population significantly preferred the species-typical chirped song, whereas flies significantly preferred a trilled song, which is expressed by other hosts in different regions. Sexual selection due to female choice and natural selection due to fly predation both appear to favor the chirped song structure of G. lineaticeps in the parasitized population, whereas sexual selection favors the chirped structure in the non-parasitized population.     

Character Displacement and Acoustic Insects

Crickets, katydids, grasshoppers, and cicadas should be idealfor illustrating character displacement. Their species-specificcalling songs are of direct importance to reproductive success,and species with similar songs and overlapping ranges shoulddevelop greater differences in their songs in areas of sympatry.Although many pairs of species have suitably similar songs andoverlapping ranges and the data concerning songs are extensivefor crickets and katydids, no convincing example of characterdisplacement has been found in acoustic insects. Lack of suchexamples can be attributed to false premises, to divergencecompleted in allopatry. to elimination of geographical variationin song by gene flow between the zone of sympatry and the zonesof allopatry, and to the scanty sample that has been intensivelystudied.     

Relative Amplitude of Courtship Song Chirp and Trill Components Does Not Alter Female Teleogryllus oceanicus Mating Behavior

Low‐amplitude acoustic signals intended for short‐range communication, often called soft songs, remain poorly studied, especially among acoustically communicating invertebrates. Some insects do employ low‐amplitude acoustic signals, but it remains unclear what the specific function, if any, is of quietness per se. Male Teleogryllus oceanicus, or Pacific field crickets, produce a two component, short‐distance courtship song consisting of a high‐amplitude series of chirps followed by a lower‐amplitude trill. We investigated whether female T. oceanicus prefer to mate with males that sing courtship songs containing trill components that are equally as loud as (?0 dB) or quieter than (?3 dB and ?10 dB) the loudest chirp (90 dB). We found no evidence that modifying trill amplitude affects female mate preference. We did, however, find that previously unmated females were faster to mount males than were females that had mated once before. Previous mating status showed no significant interaction with trill amplitude. What, if any, function of low‐amplitude components of field cricket courtship song remains to be determined.     

Death comes suddenly to the unprepared: singing crickets, call fragmentation, and parasitoid flies

Male field crickets are subject to a delicate dilemma becausetheir songs simultaneously attract mates and acoustic predators.It has been suggested that in response, crickets have modifiedvarious temporal song parameters to become less attractiveto acoustic predators. We investigated whether crickets withchirping (versus trilling) song structures are less likely toattract acoustically orienting parasitoid flies. Experimentally,we evaluated the phonotactic quest of the parasitoid fly Ormiaochracea in response to broadcast cricket calls, presentedboth simultaneously (choice paradigm) and sequentially (no-choiceparadigm). Flight trajectories were recorded in darkness usingthree-dimensional active infrared video tracking. The flies showed remarkable phonotactic accuracy by landing directly onthe loudspeaker. The introduction of acoustic fragmentationthat resembles calls of many chirping crickets altered theflies' phonotactic accuracy only slightly. Our results documentdifferential attraction between trilling and chirping cricket songs and quantitatively demonstrate that chirping songs, ifpresented alone, do not impair the efficiency (temporal investmentand landing accuracy) of the flies' phonotactic quest. Thisstudy shows that song fragmentation is no safeguard againstacoustic parasitism. We conclude that, in general, a cricket may reduce predation only if its neighbors are acousticallymore conspicuous, chiefly by amplitude.     

Calls of Recently Introduced Coquí Frogs Do Not Interfere with Cricket Phonotaxis in Hawaii

Acoustically-signaling animals such as crickets may experience interference from environmental noise, a particular concern given the rise in anthropogenic or other novel sources of sound. We examined the potential for acoustic interference of female phonotaxis to calling song in the Pacific field cricket (Teleogryllus oceanicus) by invasive coqui frogs (Eleutherodactylus coqui) in Hawaii. The frogs were introduced to Hawaii from Puerto Rico in the 1980s. When female crickets were exposed to male calling songs with and without simultaneous broadcast of a coqui chorus, they were equally likely to move toward the cricket song, regardless of the location of the frog sound (ground level or above ground). Unlike some species of frogs and birds, T. oceanicus do not appear to experience acoustic interference from an introduced signaler, even though the introduced species’ calls subjectively seem to be masking the crickets’ songs.