Full Description

"Sounds produced by the Shi drum Umbrina cirrosa were short trains of pulses with an average pulse period of 180 ms, pulse duration of c. 40 ms and an average peak frequency of 400 Hz;"

"Umbrina cirrosa calls consisted mainly of a series of two pulses (74% out of 1160 sounds; range: 1–11 pulses) with most of the energy below 2 kHz and a mean peak frequency of 440 Hz (Fig. 1). Individual calls lasted c. 240 ms, single pulse duration was on average c. 40 ms and pulse period was c. 180 ms. The number of pulses per call showed a positive correlation with call duration (Spearman rank correlation, n = 1042, r = 0_655, P < 0_001) and a negative correlation with pulse period (Spearman rank correlation, n = 1042, r = 0_636, P < 0_001) and sound peak frequency (Spearman rank correlation, n = 1042, r = 0_062, P < 0_05). The peak frequency was significantly correlated with the pulse period (Spearman rank correlation, n = 1042, r = 0_182, P < 0_001). In contrast to Lagardère & Parmentier (2014), who reported two types of call from U. cirrosa sounds, lasting respectively 60–90 and 140–160 ms, the present study showed a continuous range of variability in sound duration, ranging from c. 150 to 1400 ms. This variability reflected differences in the number of pulses making up each call: while Lagardère & Parmentier (2014) described calls made of 1–3 pulses, a maximum of 11 pulses per call was observed in the present study. In terms of spectral properties, a much higher mean peak frequency (c. 400 Hz) was observed in comparison to that reported by Lagardère & Parmentier (2014), where the peak frequency range was 150–250 Hz. The mean peak frequency of call in the present study, however, showed a great range of variation, from c. 100 up to 500 Hz. Three factors could explain these discrepancies: the call sample size (1160 v. 11), and differences in the age and size of U. cirrosa. In the present study, the investigation involved a single U. cirrosa cohort (of 3 year old individuals) while Lagardère & Parmentier (2014) were reporting results from U. cirrosa that had reached the upper size and age limit for this species (six large individuals, 2_5–6 kg)."

Observation Environment Quotes

"The study took place in the Veneto Agriculture Bonello Trial Fishing Centre (Porto Tolle, Rovigo, Italy) in a large aquaculture tank (outdoor pond of 1_5 m depth and 0_2 ha in area, supplied with seawater)."

"(a) Oscillogram and(b) sonogram of three sounds made by the Umbrina cirrosa (Sciaenidae) recorded in semi-natural conditions and (c) structure of three pulses from a U. cirrosa sound [Hamming window, fast Fourier transformation (FFT) size = 125]."

Sound Name Quotes

"Sounds produced by the Shi drum Umbrina cirrosa were short trains of pulses with an average pulse period of 180 ms, pulse duration of c. 40 ms and an average peak frequency of 400 Hz;"