Full Description

"Modifications of the male sonic apparatus during sexual maturation are related to important modifications in sound characteristics (Kéver et al., 2014b) and the sexual dimorphism in the sound production mechanism of O. rochei has been associated with completely distinct sound types (Kéver et al., 2012): long and pulsed sounds in males, and short and more tonal sounds in females (Fig. 1). Male calls show a unique pattern: the pulse period increases through the first several pulses, then it alternates between long and short durations in successive pulses (Parmentier et al., 2010; Kéver et al., 2012)."

"In females, the slopes for pulse duration and pulse number against temperature did not differ from zero [Fig. 2(a), (b)]. On the other hand, pulse period and sound frequencies were strongly correlated with temperature (r2 > 0_8): pulse period correlated negatively with temperature, whereas the fundamental frequency and related harmonics were positively correlated with this factor [Fig. 2(c), (d)]. In males, alternation start and pulse number [Fig. 3(a), (b)] were negatively (although weakly) correlated with temperature: the alternation start happened later in the call and pulse number was higher at lower temperatures [Fig. 3(a), (b)]. Short and long pulse periods decreased with seawater temperature (r2 ≥ 0_83) [Fig. 3(c), (d)] while the first and second peak frequency increased (r2 ≥ 0_73) with temperature [Fig. 3(e), (f)]."

"In both sexes, temperature increases were associated with shorter pulse periods and higher frequencies."

"Although peak frequency increased with temperature, sound frequency is independent from contraction rate in male calls for at least two reasons: the fundamental frequency (c. 250 Hz) does not match with the pulse period (c. 100 ms) and dominant frequency is constant throughout the call despite differences in pulse period within a call (Parmentier et al., 2010)."

Observation Environment Quotes

"In O. rochei, the reproductive period lasts from June to September (Jardas, 1996). Sounds were recorded at night in May 2010, July 2010 (Kéver et al., 2012), September 2008 (Parmentier et al., 2010) and September 2011 in Duce-Glava (Croatia) at 2 m ´ depth. The water temperatures were 13_5, 21_5, 23_5 and 25_ C, respectively. A few additional male calls were recorded from 9 to 10 August 2010 in Banyuls-sur-mer (France) at 27 m depth with the temperature 17_5_ C."

Sound Name Quotes

"Modifications of the male sonic apparatus during sexual maturation are related to important modifications in sound characteristics (Kéver et al., 2014b) and the sexual dimorphism in the sound production mechanism of O. rochei has been associated with completely distinct sound types (Kéver et al., 2012): long and pulsed sounds in males, and short and more tonal sounds in females (Fig. 1). Male calls show a unique pattern: the pulse period increases through the first several pulses, then it alternates between long and short durations in successive pulses (Parmentier et al., 2010; Kéver et al., 2012)."