Full Description

"Fortunately, male O. rochei produce long, multiple-pulsed calls that are easy to identify."

"Sound production followed diel cycles: it was sustained for the entire night at the beginning of the sound production season but limited to shorter periods in the evening during the second half of the season."

"In this species, both sexes are able to produce sounds; female sounds are short with a regular, short duration pulse period while male sounds (Fig. 1) are much longer, pulsed and show a unique pulse period pattern (Kever et al. 2012)."

"The identification is mainly based on the speciesspecific pulse period pattern with the pulse period progressively increasing in the first part of the sound before alternating between long and short durations (Fig. 1). In addition, we verified that pulses were dominated by two peak frequencies and that the values for pulse duration, peak frequencies and pulse number were in the same range as in our previous recordings of male O. rochei."

"The long and short pulse periods (Fig. 1) were measured for 10 calls per month because Kever et al. (2015) reported that Ophidion rochei pulse periods vary with seawater temperature."

"No female sounds were identified during field recordings in Corsica. No male sounds were recorded from November 2011 to May 2012 (Fig. 2B). Only one sound was recorded in October 2011 (1 October) and another one in June 2012 (14 June)."

"During summer 2011, the sound production was significantly higher in July (one-way ANOVA, P < 0.05; Tukey’s HSD, P < 0.05,) with 17 +- 5 sounds recorded per day (mean +- SD; Fig. 2B)."

"In 2013, the recordings lasted from 7 June to 2 July. Many more sounds were recorded than in June 2012 (Fig. 2B): 470 sounds were recorded from 7 to 21 June 2013 while a single sound was obtained during that period in 2012. Daily sound production (mean +- SD: 31 +- 6 sounds) was also significantly higher (t-test, P < 0.05) than in July 2011."

"Despite mean values for both short and long pulse periods (Fig. 2C) being shorter in September 2011 (103 +- 17 ms, n = 10 and 132 +- 21 ms, n = 10, respectively) than in July 2011 (122 +- 15 ms, n = 10 and 151 +- 19 ms, n = 10, respectively), August 2011 (123 +- 6 ms, n = 10 and 153 +- 8 ms, n = 10 respectively) and June 2013 (123+- 5 ms, n = 10 and 148 +- 7 ms, n = 10, respectively), a significant difference (Bonferroni-corrected Mann–Whitney, P < 0.05) was only observed between the short pulse periods measured in September and July 2011."

"Male Ophidion rochei calls were recorded only between sunset and sunrise; no sounds were recorded during daytime."

"In short, during the first part of the sound production period, males called all night long while later in the season (longer night-time) they produced sounds almost exclusively shortly after sunset."

"The multiple-pulsed sounds of male Ophidion rochei are produced at night from June to early October. According to Jardas (1996), the reproductive period of this species lasts from June to September."

"The sound production season of male O. rochei fits very well with its spawning season, which suggests an important function related to reproductive behavior."

"Here, sound production of male O. rochei started approximately 1 h after dusk and sometimes lasted for the whole night. The highest sound production rate was observed 1–3 h after sunset. A second, but smaller, peak often occurred approximately 2 h before sunrise."

"Our long-term recordings show that in O. rochei, the pattern of daily sound production varied during the reproductive period. Males first called all night long but later in the season, sound production was concentrated shortly after sunset, showing that fish most probably change their behavior during the spawning period."

"Male Ophidion rochei probably call during courtship and mating behaviors and many factors have been reported to affect the timing of fish reproduction: photoperiod, temperature, lunar phase, rainfall, food availability, habitat availability, pheromone presence and sex ratio (Bromage et al. 2001; Takemura et al. 2004; Migaud et al. 2010)."

"Cooler temperatures can delay gonadal development, which may explain some differences in spawning time (Hutchings & Myers 1994). Photoperiod is consistent from 1 year to another but temperature is not. As temperature was higher during late April 2013 and the first half of May 2013 compared with the same period in 2012 (dashed lines in Fig. 4), seawater temperature could be a good candidate to explain the earlier sound production period in 2013. Higher temperatures were recorded for several days in May 2013 and may have promoted an earlier sound production onset (e.g. hormonal changes)."

Observation Environment Quotes

"A hydrophone was deployed from 18 July 2011 to 21 June 2012 and from 7 June 2013 to 2 July 2013 on a sandy area (42°3404800 N, 8°4304300 E) in front of the STARESO research station (NW Corsica)."

Behaviour Description Quotes

"The sound production season of male O. rochei fits very well with its spawning season, which suggests an important function related to reproductive behavior."

"Male Ophidion rochei probably call during courtship and mating behaviors and many factors have been reported to affect the timing of fish reproduction: photoperiod, temperature, lunar phase, rainfall, food availability, habitat availability, pheromone presence and sex ratio (Bromage et al. 2001; Takemura et al. 2004; Migaud et al. 2010)."

Sound Name Quotes

"In this species, both sexes are able to produce sounds; female sounds are short with a regular, short duration pulse period while male sounds (Fig. 1) are much longer, pulsed and show a unique pulse period pattern (Kever et al. 2012)."

"Waveform of a male Ophidion rochei call recorded in July 2011 in Calvi Bay (France). Gray: long pulse periods, white: short pulse periods."