Full Description

"The present study was a multidisciplinary investigation (morphology, muscle histology, high-speed video, sound analysis and electromyography) of the sound emission mechanism in Gobius paganellus, which produces both pulsed and tonal calls."

"In addition, we propose that different sound types (pulsed sounds and tonal calls) could occur because of differences in fish size."

"With few exceptions, goby calls can be grouped into three major sound types: (1) pulsed sounds that consist of pulse trains repeated at a slow rate and that can be amplitude modulated; (2) tonal sounds characterized by faster pulse repetition rates, where pulses fuse resulting in a sinusoidal-like waveform; and (3) complex sounds that are made of a combination of the two (Lugli et al., 1997)."

"According to Malavasi and colleagues (Malavasi et al., 2008), G. paganellus calls are tonal sounds lasting ca. 350 ms, composed of 30 pulses with a pulse rate of 90 Hz, and the dominant frequency is around 300 Hz."

"In G. paganellus that were collected on the French coast, pulsed calls lasted between 127 and 313ms (mean ± s.d. 192±52.5ms, N=31) and were made of 6–22 pulses (11±5 pulses, N=31). The amplitude of the pulses progressively increased during the first two-thirds of the call before decreasing. Pulses lasted between 19.0 and 22.4ms and the pulse period ranged from 33 to 139Hz (60±23Hz, N=31). Sounds were harmonic and the fundamental frequency (95–280Hz) was not necessarily the main frequency, which can be the first or the second harmonic in some cases. In Italy, most of the calls were tonal. Calls lasted between 113 and 643ms (344±109ms, N=124) and were made of 15–62 pulses (31±7 pulses, N=124). Pulse period ranged from 60 to 143Hz (93±17Hz, N=124) and fundamental frequency from 61 to 220Hz. Italian and French calls were significantly different (Mann–Whitney test, P<0.05) for all characteristics: pulse duration, pulse number, pulse period and fundamental frequency. Generally, French sounds were more pulsatile than Venetian sounds, but occasionally French sounds appeared tonal. Conversely, most Italian sounds were tonal, but a few pulsatile calls were also recorded. The presence of pulsed and tonal sounds in both populations shows fish are able to modulate their signals (Fig.1)."

"A pair of electrodes was placed in right and left levator pectoralis muscle. EMG recordings revealed burst activity coincident with sound emission (Fig.7). Peak-to-peak duration in EMG showed a period of 8.1±0.7ms (N=83 from five bursts), which corresponds perfectly with the fundamental frequency of the calls. Therefore, the pulse contraction rate determines the sound frequency in G. paganellus. The amplitude of the EMG was not constant during the call, increasing to a plateau and, in some cases, decreasing towards the end of the call. A short delay of 1ms was recorded between the left and right electrodes, but we cannot explain it. Also, differences between the two graph shapes are probably due to the electrode position or to difference in connectivity of the electrodes."

Observation Environment Quotes

"Gobius paganellus Linnaeus 1758 specimens were caught during February and March 2010 and 2011 in Brittany, France. They were caught by hand during the low tide in front of Saint-Malo and in Roscoff, and transported to the laboratory (Liège, Belgium). These specimens (total length, TL 56_105mm, N=18) were kept in two tanks (150_40_45cm) with gravel on the bottom and fragments of terracotta bowls on a 12h:12h light:dark cycle."

Behaviour Description Quotes

"This study dealt with the sound-producing mechanism and not with ethology; we did not try to determine the sex of the added fish or to qualify the sonic message, the aim was just to obtain sounds."

"A pair of electrodes was placed in right and left levator pectoralis muscle. EMG recordings revealed burst activity coincident with sound emission (Fig.7). Peak-to-peak duration in EMG showed a period of 8.1±0.7ms (N=83 from five bursts), which corresponds perfectly with the fundamental frequency of the calls. Therefore, the pulse contraction rate determines the sound frequency in G. paganellus. The amplitude of the EMG was not constant during the call, increasing to a plateau and, in some cases, decreasing towards the end of the call. A short delay of 1ms was recorded between the left and right electrodes, but we cannot explain it. Also, differences between the two graph shapes are probably due to the electrode position or to difference in connectivity of the electrodes."

Sound Name Quotes

"The present study was a multidisciplinary investigation (morphology, muscle histology, high-speed video, sound analysis and electromyography) of the sound emission mechanism in Gobius paganellus, which produces both pulsed and tonal calls. "

" In addition, we propose that different sound types (pulsed sounds and tonal calls) could occur because of differences in fish size."