饰纹姬蛙求偶鸣声特征分析

2012年5月,用SX950录音笔和Praat声音分析软件对浙江丽水繁殖季节饰纹姬蛙(Microhyla ornata)求偶鸣声进行录制和特征分析.结果表明,饰纹姬蛙发出的求偶鸣声具有单一谐波鸣声结构、多脉冲(7、9～16)及纺锤形振幅等特征；所有鸣声主频率范围为1.22～4.09 kHz (n=233),且由不同脉冲数组成的鸣声主频率平均值几近相等；叫声时程随脉冲数的增加而增大,脉冲时程在不同脉冲数鸣声中的大小几近相等,但最后一个脉冲的时程大小≤其他脉冲；脉冲间隔与叫声时程则刚好相反,即叫声时程越短,脉冲间隔就越大.在7个脉冲的鸣声中,其脉冲间隔最大,脉冲率最小；而在16个脉冲的鸣声中,脉冲间隔则最小,脉冲率最大.除7个脉冲和16个脉冲鸣声的脉冲率分别与其他鸣声存在显著性差异以外,随着叫声时程和脉冲数的增加,脉冲率也出现相应变化.在声强方面,除16个脉冲鸣声与其余所有的脉冲鸣声出现显著性差异以外,其他脉冲鸣声之间的两两比较差异不显著.丽水种群与其他5个地理种群(杭州、宣城、Kamoor、Bajipe和Padil)的鸣声特征比较显示饰纹姬蛙在不同地理种群的鸣声结构相似,而鸣声主频率、叫声时程、脉冲时程及脉冲率等在6个地理种群种均出现不同程度的差异.了解不同物种的声信号特征有助于更好地理解动物通讯行为及其进化特点.

Characteristics of courtship calls of Microhyla ornata (Anura: Microhylidae)

During breeding season in May, 2012, we recorded and analyzed the courtship calls and the acoustic parameters of the male Microhyla ornate in Lishui, Zhejiang province using an IC recorder (SX950) and the sound software Praat. We observed that the male M. ornate produced calls characterized by a single harmonic call structure, multiple pulses (7, 9?16) and spindle amplitudes. Analyses of the calls revealed several interesting findings: the dominant frequency of all calls ranged from 1.22?4.09 kHz (n=233); their average values composed of different numbers of pulses were similar and that call duration increased with numbers of pulses; and pulse duration among different multi-pulse call groups was nearly identical, but it was equal or less in the last pulse than other pulses. By contrast, our analyses also showed that pulse interval was negatively correlated with call duration, i.e. the shorter in call duration, the longer in pulse interval among the different numbers of pulses call groups. Within the 7-pulse call group, calls exhibited the largest in pulse interval and the smallest in pulse rate, while those calls in 16-pulse were the opposite. Except that the 7- and 16-pulse call groups were both significantly different in pulse rate with other multi-pulse call groups, we found that pulse rates expressed different variations between pair-wise comparisons of the remaining call groups. As for call intensity, significant differences were only found between the 16-pulse call group and the other call groups, while pairwise comparisons of the remaining groups were not significant. After conducting our initial analyses, we compared the calls of the M. ornate population from Lishui with populations from five other localities—Hangzhou, Xuancheng, Karnoor, Bajipe and Padil—and found that the call structures were similar among the different populations, being single harmonic, while we observed differences in call dominant frequency, call duration, pulse duration and pulse rate among the six populations. This research should prove useful to in furthering our understanding of the acoustic properties of species-specific calls as well as their behavior and the evolution of their communication, thereby providing a robust insight into the reproductive traits among different geographical populations of a species.