中文摘要：

通过2009年10月至2010年7月监测高黎贡山大塘的3群东部白眉长臂猿的鸣叫行为,收集了10个月（200d）的数据,发现东部白眉长臂猿的鸣叫行为主要发生在黎明后4h内;平均每次鸣叫持续14min59s,不同群体间鸣叫持续时间不同。天气情况影响东部白眉长臂猿的鸣叫开始时间（相对黎明）和持续时间,在雨天鸣叫相对黎明开始时间较晚,持续时间也较长。东部白眉长臂猿鸣叫频率在10月和11月明显高于其他月份,可能与食物（果实）的丰富度有关。根据研究结果,建议对东部白眉长臂猿的调查最好集中在10月或11月;每天监测时间至少持续至黎明后4h,以覆盖长臂猿90%以上的鸣叫;如果出现下雨天气,应适当延长调查时间。

英文摘要：

We monitored the singing behavior of three groups of eastern white-browed gibbon（Hoolock leuconedys） at Datang,Gaoligongshan Nature Reserve between October 2009 and July 2010,totally 200 days.Most gibbon calls occurred within 4 hours after dawn.On average,one call bout lasted 14 minutes and 59 seconds.Significant difference was found in call duration among groups.Weather influenced the start time（relative to dawn） and call duration of gibbons.Gibbons called later and longer in rainy days.Gibbons called more often in October and November when food（fruit） was possibly more abundant in the site.Based on our results,we suggested that October or November is good season for wild survey of eastern white-browed gibbon in Gaoligongshan;survey should cover at least 4 hours after dawn in order to hear more than 90% calls;and more days are suggested if it is rain.