雄性凹耳蛙的争斗鸣声及其打斗行为

Combat Calls and Fighting Behavior of the Male Odorrana tormotus

2017年4月17日,在黄山浮溪完整地记录了2只雄性凹耳蛙(Odorrana tormotus)之间争夺领地的打斗过程、争斗鸣声以及其中一只蛙打斗后的鸣声,并用摄像机记录了此行为的过程。争斗大约持续了8 min,并产生了一个胜利者和一个失败者。实验共录了胜利蛙的争斗鸣声17声,打斗后鸣声7声,失败蛙的争斗鸣声6声,其中两只蛙同时鸣叫了1声。随后通过Praat语音软件获取鸣声的时域参数和频谱参数,并利用T检验来判断两只蛙争斗鸣声参数是否具有显著差异,以及胜利蛙打斗时与打斗后的鸣声参数是否具有显著差异。对两只蛙争斗鸣声的时域和频谱参数分析发现,胜利蛙以多音节鸣叫为主,其平均基频(8 150±1 305)Hz、最大基频(9 741±1 283)Hz、最小基频(5 809±1 139)Hz以及最大最小基频差(3 932±1 122)Hz都高于失败蛙,尤其是平均基频和最大基频(P <0.05),而最小基频以及最大最小基频差二者差异并不显著(P> 0.05),但是胜利蛙的主频却要略低于失败蛙(P>0.05);失败蛙的鸣声中非线性片段时长占总时长的百分比更大,甚至超过50%。将胜利蛙的争斗鸣声与打斗后鸣声进行比较,发现总时长、非线性片段时长和平均基频在争斗后都有明显减小(P <0.05),最大基频、最小基频有略微减小(P> 0.05),而音节间隔时间占总时间的百分比和大小基频差都有所增大(P> 0.05),这可能是为了在争斗过程中更快地击退对手。因此,推测胜利蛙获取胜利的原因可能是因为其具有较高的鸣叫率以及较低的主频。本文描述了雄性凹耳蛙争斗过程中的鸣声特征,可对凹耳蛙雄性之间的竞争过程有更进一步的了解。

We recorded the calls of two male Odorrana tormotus and video-taped their interactions during a territorial combat at Fuxi,Mount Huangshan on 17April,2017.The combat lasted about eight minutes,and produced a winner and a loser.The winner emitted 16calls during the combat and 7calls after the combat. The loser uttered 5calls during the combat.At one instant during the territorial encounter,both frogs emitted a call simultaneously.For this study,we used the software Praat to obtain various temporal and spectral parameters,and sheng employed T test to determine whether there was a significant difference in parameter of each call during the combat between two frogs.The winner produced multi-note calls mostly and his calls was with an average fundamental frequency of 8150±1305Hz;the maximum and minimum fundamental frequency was 9741±1283Hz and 5809±1139Hz.The difference between the maximum fundamental frequency and the minimum fundamental frequency was 3932±1122Hz.All the values above was higher than those of the loser's made,especially on average fundamental frequency and the maximum fundamental frequency (P <0.05).However,the differences in minimum fundamental frequency and maximum fundamental frequency and the in the minimum fundamental frequency were not significant (P >0.05).But the dominant frequency produced by the winner was significantly lower than loser's (P >0.05).The total call durations of winner and loser were 0.57±0.09s and 0.51±0.11s,respectively.The time duration of calls of this species was longer than the duration of advertisement calls of non-combat O.tormota.Comparing to the winner the loser's calls contained more abundant nonlinear phenomena (NLP);the duration of NLP segments was >50%longer for the loser than for the winner.The total duration and NLP durarion of combat and post-combat calls for the winner were shorter (P <0.05)than the loser,the average fundamental frequency was significant decrease (P <0.05),the maximum fundamental frequency and the minimum fundamental frequency were all lower after winning the combat (P >0.05),but the break duration was longer.The difference between the maximum fundamental frequency and the minimum fimdamental frequency was greater (P >0.05).It appeared that winner increased the call rate as well as the dominant frequency in order to fight offthe opponent.This article described the calling characteristics of male O.tormotus during a territorial combat.It increases our knowledge of signal plasticity in this species.