摘要
20 0 3年在安徽扬子鳄自然保护区对扬子鳄的吼叫规律进行了为期一年的专题研究。在监测中 ,记录了吼叫日期、吼叫时间、吼叫数和天气情况。扬子鳄在每年的 3月开始吼叫 ,11月停止吼叫 ;扬子鳄的吼叫数在不同的月份差异极显著 (χ2 检验 :χ2 =4 4 8 2 9,df=8,P <0 0 1) ,其中 6月扬子鳄吼叫最为频繁 ,其吼叫数占全年的 2 6 0 % ;繁殖期间 (6— 9月 )扬子鳄吼叫数明显高于非繁殖期 (Mann WhitneyU检验 :U =2 0 ,P <0 0 5 ) ;在每天的不同时间扬子鳄的吼叫数呈极显著差异 (χ2 =2 33 18,df =17,P <0 0 1) ,存在明显的吼叫高峰 ,白天吼叫多于晚上 (U =12 5 ,P <0 0 5 ) ;天气的变化对吼叫没有影响。分析表明 ,扬子鳄的吼叫与其繁殖行为关系紧密 ,吼叫的主要目的是为了吸引异性 ,同时有保护领域的功能。
The study of bellowing of Chinese alligators (Alligator sinensis) was carried out during the period of 2003 in Hongxing reservoir (30°46′N,118°41′E) of Xuancheng,Anhui,China.The reservoir contains a small group (8-10 individuals) of wild and reintroduced alligators.When the bellow was heard,we recorded the date,time and number of bellows,and the weather condition.The results showed that the Chinese alligator began to bellow in March,and ended in November.The bellowing varied markedly on an annual basis (χ~2 test:χ~2=448.29,df=8,P<0.01).The Chinese alligator bellowed most frequently in June,which accounted for 26.0% of the annual total.There was a significant different in the frequency of alligator bellowing between the reproductive period and non reproductive period (Mann-Whitney U test:U=2.0,P<0.05).The average number of bellows per month was 128 (SD=71.11,n=4) during the reproduction period,and it was obviously higher than that during the non reproductive period.The frequency of bellows also varied significantly on a diurnal basis (χ~2=233.18,df=17,P<0.01) with two obvious peaks at 6:00-7:00 and 10:00-11:00.The frequency of bellows differed significantly between 06:00-18:00 and 18:00-24:00 (U=12.5,P<0.05),and it was inversely related to the alligator’s activity.We observed no effect of weather conditions on the frequency of bellowing.Those results indicate that the Chinese alligator’s bellowing has a close relationship with the reproductive behavior in the wild.The bellowing is believed to play an important role for attracting the opposite sex during the mating period,and has close relationship with females’ protecting their eggs and young in the hatching period.Moreover,the bellowing has the function of territorial protection and possibly defense of food-resources.
基金
教育部跨世纪优秀人才培养计划
国家"2 11"重点建设生态学科基金
上海市重点学科 (生态学 )基金
国际野生生物保护学会 (TheWildlifeConservationSociety)资助项目
