Full Description

"Type I, “singing” males build and guard egg-containing nests in the rocky intertidal zone, and acoustically court females at night. Type II males neither build nests nor sing to females, but instead sneak or satellite spawn from positions inside or just outside a type I male’s nest. Type I males produce two types of stereotyped vocalizations, advertisement and agonistic calls, that are highly divergent in their temporal properties (Brantley and Bass, 1994; Bass et al., 1999; Bass and Clark, 2003; Fig. 1). Advertisement calls or “hums” are long duration (seconds to minutes) with a fundamental frequency near 90–100 Hz at 15–16 _C and several prominent harmonics extending up to almost 700 Hz (Fig. 1, top). Fundamental frequency is highly stable across a hum’s entire duration, although it varies linearly with temperature (Bass and Baker, 1991; Brantley and Bass, 1994). During the breeding season, nesting males often cluster and produce hums simultaneously (Bass, 1996; Bass et al., 1999). When two hums with slightly different fundamental frequencies overlap, the acoustic waveforms interfere to produce acoustic beats with a modulation rate established by the difference frequency (dF) between the fundamental frequencies of the two hums (Fig. 2). A second type of signal known as a “growl” is also known to be produced only by type I males, mainly at the beginning of the breeding season when males are establishing nest sites (Bass et al., 1999; Fig. 1, middle). Growls are somewhat intermediate in their appearance between hums and grunts; they are multi-harmonic and of relatively long duration (on the order of seconds) like hums, but show gradual changes in their fundamental frequency throughout the duration of the call. In contrast to hums and growls, another class of signals known as “grunts” are brief in duration (50–200 ms), broad-band, and often produced repetitively at rates of 1–2 Hz in long lasting “grunt trains” (Brantley and Bass, 1994; Bass et al., 1999, Fig. 1, bottom). Type II males and females do not hum, although they produce isolated grunts, known so far only in non-spawning contexts (Brantley and Bass, 1994). Each sound pulse within a single grunt is equivalent to a single cycle of the sound wave in tonal signals such as hums and growls. The rate of production of sound pulses in the grunt is like the pulse repetition rate or trill of the pulsatile vocalizations of other vertebrates (see Bradbury and Vehrencamp, 1998). The pulse repetition rate of individual grunts is similar to the fundamental frequency of hums and growls. Observations of spawning behavior, together with underwater playbacks, support the hypotheses that the hum serves as an advertisement call that attracts gravid females to a male’s nest and the grunt train as an agonistic call that fends-off potential intruders from the nest (Ibara et al., 1983; Brantley and Bass, 1994; McKibben and Bass, 1998, 2001a)."

Behaviour Description Quotes

"Type I, “singing” males build and guard egg-containing nests in the rocky intertidal zone, and acoustically court females at night. Type II males neither build nests nor sing to females, but instead sneak or satellite spawn from positions inside or just outside a type I male’s nest. Type I males produce two types of stereotyped vocalizations, advertisement and agonistic calls, that are highly divergent in their temporal properties (Brantley and Bass, 1994; Bass et al., 1999; Bass and Clark, 2003; Fig. 1). Advertisement calls or “hums” are long duration (seconds to minutes) with a fundamental frequency near 90–100 Hz at 15–16 _C and several prominent harmonics extending up to almost 700 Hz (Fig. 1, top). Fundamental frequency is highly stable across a hum’s entire duration, although it varies linearly with temperature (Bass and Baker, 1991; Brantley and Bass, 1994). During the breeding season, nesting males often cluster and produce hums simultaneously (Bass, 1996; Bass et al., 1999). When two hums with slightly different fundamental frequencies overlap, the acoustic waveforms interfere to produce acoustic beats with a modulation rate established by the difference frequency (dF) between the fundamental frequencies of the two hums (Fig. 2). A second type of signal known as a “growl” is also known to be produced only by type I males, mainly at the beginning of the breeding season when males are establishing nest sites (Bass et al., 1999; Fig. 1, middle). Growls are somewhat intermediate in their appearance between hums and grunts; they are multi-harmonic and of relatively long duration (on the order of seconds) like hums, but show gradual changes in their fundamental frequency throughout the duration of the call. In contrast to hums and growls, another class of signals known as “grunts” are brief in duration (50–200 ms), broad-band, and often produced repetitively at rates of 1–2 Hz in long lasting “grunt trains” (Brantley and Bass, 1994; Bass et al., 1999, Fig. 1, bottom). Type II males and females do not hum, although they produce isolated grunts, known so far only in non-spawning contexts (Brantley and Bass, 1994). Each sound pulse within a single grunt is equivalent to a single cycle of the sound wave in tonal signals such as hums and growls. The rate of production of sound pulses in the grunt is like the pulse repetition rate or trill of the pulsatile vocalizations of other vertebrates (see Bradbury and Vehrencamp, 1998). The pulse repetition rate of individual grunts is similar to the fundamental frequency of hums and growls. Observations of spawning behavior, together with underwater playbacks, support the hypotheses that the hum serves as an advertisement call that attracts gravid females to a male’s nest and the grunt train as an agonistic call that fends-off potential intruders from the nest (Ibara et al., 1983; Brantley and Bass, 1994; McKibben and Bass, 1998, 2001a)."

Sound Name Quotes

"Type I, “singing” males build and guard egg-containing nests in the rocky intertidal zone, and acoustically court females at night. Type II males neither build nests nor sing to females, but instead sneak or satellite spawn from positions inside or just outside a type I male’s nest. Type I males produce two types of stereotyped vocalizations, advertisement and agonistic calls, that are highly divergent in their temporal properties (Brantley and Bass, 1994; Bass et al., 1999; Bass and Clark, 2003; Fig. 1). Advertisement calls or “hums” are long duration (seconds to minutes) with a fundamental frequency near 90–100 Hz at 15–16 _C and several prominent harmonics extending up to almost 700 Hz (Fig. 1, top). Fundamental frequency is highly stable across a hum’s entire duration, although it varies linearly with temperature (Bass and Baker, 1991; Brantley and Bass, 1994). During the breeding season, nesting males often cluster and produce hums simultaneously (Bass, 1996; Bass et al., 1999). When two hums with slightly different fundamental frequencies overlap, the acoustic waveforms interfere to produce acoustic beats with a modulation rate established by the difference frequency (dF) between the fundamental frequencies of the two hums (Fig. 2). A second type of signal known as a “growl” is also known to be produced only by type I males, mainly at the beginning of the breeding season when males are establishing nest sites (Bass et al., 1999; Fig. 1, middle). Growls are somewhat intermediate in their appearance between hums and grunts; they are multi-harmonic and of relatively long duration (on the order of seconds) like hums, but show gradual changes in their fundamental frequency throughout the duration of the call. In contrast to hums and growls, another class of signals known as “grunts” are brief in duration (50–200 ms), broad-band, and often produced repetitively at rates of 1–2 Hz in long lasting “grunt trains” (Brantley and Bass, 1994; Bass et al., 1999, Fig. 1, bottom). Type II males and females do not hum, although they produce isolated grunts, known so far only in non-spawning contexts (Brantley and Bass, 1994). Each sound pulse within a single grunt is equivalent to a single cycle of the sound wave in tonal signals such as hums and growls. The rate of production of sound pulses in the grunt is like the pulse repetition rate or trill of the pulsatile vocalizations of other vertebrates (see Bradbury and Vehrencamp, 1998). The pulse repetition rate of individual grunts is similar to the fundamental frequency of hums and growls. Observations of spawning behavior, together with underwater playbacks, support the hypotheses that the hum serves as an advertisement call that attracts gravid females to a male’s nest and the grunt train as an agonistic call that fends-off potential intruders from the nest (Ibara et al., 1983; Brantley and Bass, 1994; McKibben and Bass, 1998, 2001a)."