BioAcoustica is a free, open repository of wildlife sound recordings from the Natural History Museum, London.
Taxonomic index of the BioAcoustica collection
Acoustic and biological measurements in the BioAcoustica collection
Recording annotations from ann-o-mate
The specimens that recordings are of, from the collections
Where the specimens that recordings are of were collected, not where the sound was recorded
| Conocephalus (Anisoptera) fuscus fuscus | 20 |
| Conocephalus discolor | GB · 1962-08-18 · David R. Ragge; J. F. Burton |
| Conocephalus discolor | ES · 1985-08-22 · W. J. Reynolds |
| Conocephalus discolor | FR · 1990-07-21 · W. J. Reynolds |
| Conocephalus discolor | GB · 1981-08-28 · David R. Ragge |
| Conocephalus discolor | FR · 1981-09-08 · E. C. M. Haes |
| Conocephalus discolor | |
| Conocephalus discolor | |
| Conocephalus discolor | |
| Conocephalus discolor |
The song is audible from about 2m. It consits of a uniform series of closely spaced sounds, which can be represented as 'tslittslittsli...'; there about ten syllables per second and the series often continues for long periods without interruptiuon.
The calling song, produced during the day-time, consists of long echeme-sequences lasting up to 4 minutes or more. The sound is faint, with a rustling or sizzling quality. Oscillographic analysis shows the sequences to consiust of trisyllabic echemes with a highly characteristic pattern. The first two syllables of each echeme consist of short opening hemisyllables followed by longer closing hemisyllables; the first diplosyllable lasts about 12-21 ms and the second, following a very short gap of 1-3 ms, is usually very slightly shorter (11-20 ms). There is then a longer gap, usually 3-13 ms, followed by the third syllable, again usually a diplosyllable but lasting longer than the first two, about 17-30 ms. Occassionally the third syllable lacks an opening hemisyllable and may thenlast for as little as 12 ms. The whole echeme lasts about 45-80 ms and successive echemes are separated by an interval of about 10-20ms; the echeme repetition rate is about 10-16/s. The hemisyllable at the beginning of each echeme id often particularly prominent. Some of the songs studied consisted only of uniform echeme-sequences of this kind (Figs 147-151), but most included short periods (usually 0.3-2.0s, rarely up to 6.0 s) of a 'ticking' sound consisting of identical syllables repeated at the rate of about 20-30/s. These were usually diplosyllables lasting about 15-25 ms, but occassionally the opening stroke was silent, leaving a closing hemisyllable lasting about 8-20 ms. These short periods of ticking were sometimes very widely spaced so that they were hardly noticeable, but in about a third of the males studied they occurred much more frequently, someties every few seconds dutring at least part of the song. (Figs 152-154). At such times the song sounds superficially like the calling song of C. dorsalis, and oscillographic analysis (or speed reduction of a recorded song) is neccessary to show that the echemes in the main part of the song are trisyllabic, unlike the tetrasyllabic echemes of C. dorsalis [= fuscus]. Occassional short bursts of ticking are probably a normal component of the calling song of C. discolor, although such bursts are much less prevalent than in C. dorsalis.
The males sing in long, continuous bursts. The frequency is at the limit of human hearing, and is rather quiet, sofor most people a bat detector is thebest way of locating singing males. Heard in this way, the song resembles a persistent 'chugging' motor. Singing males are usually evenly spread out in their habitat, although silent ('satellite') males can often be seen close to songsters. The females are attrcated to the male song.