Possible species specific courtship sounds by two sympatric cichlid fishes in Lake Malawi, Africa.

Sounds were produced by the males of two species of cichlid fishes while courting females. Each courtship sound consisted of a series of distinct pulses occurring in rapid succession. Courtship sounds produced by Tramitichromis c£ intermedius and copadichromis conophorus were significantly different, in pulse rate and individual pulse durations. For C. conophorus calls (n = 127) the mean ± sd number of pulses per call was 10±3 and call duration was 181 ± 59 ms. There was a significant positive linear relationship between call duration and the number o,i pulses (r² = 0.912, p <0.001). The dominant frequency of the pulses in calls was 471 ±50 (range 372-594) Hz (n = 40 calls). T ef. intermedius also produced a pulsed courtship call: data (mean ± sd) from two male T. cf. intermedius: 9 ±2 pulses per call and duration 199 ±44 ms (n = 20 calls). The linear regression between call duration and number of pulses was positive (r² = 0.463, p 0.001). Pulse rate within calls of T. ef. intermedius compared to C. conophorus were significantly different (p= 0.018). Individual pulse durations were also significantly different (p= 0.043) between species. However, interpulse intervals were not significantly different (p = 0.177). These cichlids produced courtship sounds that were distinct by individual pulse durations and by pulse repition rate in a call. [ABSTRACT FROM AUTHOR]