中文摘要：

2003年3月-2004年3月对无量山大寨子3群西黑冠长臂猿的二重唱的时间特征进行了监测。于2007年3月和2008年3月利用Sony TC-D5Pro2录音机、Sony C-76指向性话筒和Sony录音磁带对其二重唱进行了录音,对录音效果最好的5个声音用Signal/RTS4.0软件进行声谱分析。对无量山西黑冠长臂猿二重唱的声谱结构和时间特征的研究结果表明,雄性西黑冠长臂猿的声音由起始音节、简单的重复音节和调节音节组成。根据频率变化的强度,可以将调节音节分为弱调节音节和强调节音节。强调节音节的特征是第二个音节具有非常明显的频率变化,有时第三个音节有类似变化,变频时的最高频率可达到5828Hz。雌性长臂猿一般只会发出一种类型的声音,即固定而刻板的激动鸣叫。根据激动鸣叫是否完整可以分为成功的激动鸣叫和失败的激动鸣叫。典型的西黑冠长臂猿二重唱通常由成年雄性发起,并占主导地位,且一般由雄性结束。雌性激动鸣叫结束后,雄性马上发出调节音节与之配合,雄性调节音节与雌性激动鸣叫的时间间隔平均为2.7s。平均每个群体的鸣叫频次为53%。如果发生鸣叫,一个群体平均每天鸣叫1.09次。91.5%的鸣叫发生在日出前0.5h至日出后3h之间,其中48.6%的鸣叫发生在日出后1h内。在一次鸣叫中,雌性平均发出成功的激动鸣叫4.6次,两次成功的激动鸣叫之间的时间间隔平均为115s。群体间均未显示鸣叫频次和持续时间上的差异,但激动鸣叫次数和激动鸣叫时间间隔具有显著差异。

英文摘要：

We studied the sonogram and timing of duets of three groups of Central Yunnan western black crested gibbons （Nomascus concolor jingdongensis） in Dazhaizi, Mt. Wuliang. The study was based on a 13-month field observation period, from March 2003 to March 2004. A Sony TC-D5 Pro2 recorder, Sony C-76 directed microphone, and Sony tape were used to record the duet bouts in March 2007 and March 2008. Signal/RTS 4.0 was used to analyze the sonogram of the duet. We first presented sonograms of all kinds of sound units in the duets made by western black crested gibbons. The adult male could produce boom, aa notes and modulated figures. Adult females produced great call or abortive great call. The two adult females in each group usually produced great calls synchronously. After the great call, males always immediately produced a modulated figure to coordinate with the female. The interval between the modulated figure and great call was 2.7 s. On average, groups sang on 53% of days monitored, and sang 1.09 duet bouts per singing day. 91.5% of the duets were produced between half an hour before and three hours after the sunrise. The average duration of the duets was 12.9 min, and females produced 4.6 great calls during one duet bout. The intervals between two successive great calls were generally 115 s. There was no significant difference in the duration and frequency of the duet bouts, but there was significant difference in the number of the great calls and intervals between great calls among groups.