Full Description

"Based on new signal analysis of striped cusk-eel sounds made in captivity, we identify that species as the source of the chatter sound in our field recordings. The dominant frequency of the sounds increased while the pulse period decreased over the temperature range 18.0–27.5 C."

"Oscillograms of the field recorded chatter (Fig. 1A) and the captive striped cusk-eel call (Fig. 1B) revealed that both sounds consisted of a long train of pulses followed by a shorter train of three pulses. Although long pulse trains often preceded short pulse trains in both field recordings and captive striped cusk-eel sounds, this did not occur in all cases in either group of recordings. The field-recorded long chatter (Fig. 1A) consisted of 32 pulses with pulse period 46.7 ms (equivalent to a pulse repetition rate of 21.4 pulses/sec), and the captive striped cusk-eel long call (Fig. 1B) consisted of 19 pulses with pulse period 43.5 ms (pulse repetition rate 23.0 pulses/sec). The sonogram of the chatter recording (Fig. 1C) consisted of a series of rapid broad-frequency pulses of 1–2 kHz. The sonogram of the captive striped cusk-eel recording (Fig. 1D) also consisted of rapid pulses with sound energy between 1 and 2 kHz."

"The average power spectra of the same two sounds indicated that the dominant frequency of the field-recorded long chatter (Fig. 3A) was 1.182 kHz, whereas the dominant frequency of the captive striped cusk-eel long call (Fig. 3B) was 1.218 kHz."

"The maximum sound pressure levels of recorded chatters ranged from 110–123 dB re 1 mPa (averaging meter, time constant 100 ms). The number of pulses in each chatter ranged from 1 to 73, with median 31 and standard deviation 15.2. We found 16 short chatters with four or fewer pulses, and the next shortest chatter had 14 pulses. We omitted the short chatters from our regression analysis because they were clearly representative of a different class of sounds than the longer chatters (Mann et al., 1997)."

"There was a significant decrease in pulse period (Fig. 4B) and a significant increase in dominant frequency (Fig. 4C) as the temperature increased from 18 to 27 C at our study sites."

"This is similar to the measured mean pulse period of 43.0 6 1.2 ms for long cusk-eel calls (Mann et al., 1997)."

"The number of pulses in our field-recorded long chatters was higher than the number of pulses produced in the captive striped cusk-eel recordings of Mann et al. (1997). Those authors observed three classes of sounds in their recordings: 1–5, 6–14, and 16–27 pulses. Sixteen of our field-recorded chatters fell into the 1–5 pulse category and one into the 6–14 pulse category. The rest of our chatters (80 total) were in the 16–27 pulse category or longer. These differences in the numbers of pulses could be a result of influences of the tank environment on striped cusk-eel behavior."

Observation Environment Quotes

"We recorded fish sounds in the Pamlico and Bogue Sounds of North Carolina using an InterOcean Model 902 Acoustic Listening and Calibration System (frequency range: 20 Hz to 10,000 Hz; sensitivity: 100 dB re 1 mPa RMS pressure) consisting of an InterOcean Model T-902 hydrophone (omnidirectional with sensitivity2195 dB re 1 V/mPa) and amplifier (gain 15–95 dB). "

" The recording of a captive striped cusk-eel was made as described in Mann et al. (1997) and was sent to us by one of the authors (DAM). We digitized the captive striped cusk-eel recording with sampling frequency 24 kHz using the same analogto-digital equipment as used for the field recordings."

Behaviour Description Quotes

"Although we did not observe striped cusk-eels producing our field-recorded chatters, Mann et al. (1997) recorded similar sounds during courtship activity. Therefore, it is likely that the striped cusk-eels in our field recordings were involved in courtship and mating behavior at our study sites."

Sound Name Quotes

"Based on new signal analysis of striped cusk-eel sounds made in captivity, we identify that species as the source of the chatter sound in our field recordings. The dominant frequency of the sounds increased while the pulse period decreased over the temperature range 18.0–27.5 C. "

"Oscillograms of the field recorded chatter (Fig. 1A) and the captive striped cusk-eel call (Fig. 1B) revealed that both sounds consisted of a long train of pulses followed by a shorter train of three pulses. Although long pulse trains often preceded short pulse trains in both field recordings and captive striped cusk-eel sounds, this did not occur in all cases in either group of recordings. The field-recorded long chatter (Fig. 1A) consisted of 32 pulses with pulse period 46.7 ms (equivalent to a pulse repetition rate of 21.4 pulses/sec), and the captive striped cusk-eel long call (Fig. 1B) consisted of 19 pulses with pulse period 43.5 ms (pulse repetition rate 23.0 pulses/sec). The sonogram of the chatter recording (Fig. 1C) consisted of a series of rapid broad-frequency pulses of 1–2 kHz. The sonogram of the captive striped cusk-eel recording (Fig. 1D) also consisted of rapid pulses with sound energy between 1 and 2 kHz."