于 2 0 0 1年 3～ 7月采用颜色标记法 ,记录厦门白鹭保护区内鸡屿岛白鹭 (Egrettagarzetta)卵产出和孵出的顺序和时间 ,并称重卵和雏鸟。有 91 4 %的窝卵数为 4～ 5枚 ,产卵期 7 0± 1 9d ,出壳期 4 2± 1 4d ;卵孵化时间与产卵顺序显著负相关 ;不同产出顺序卵重无差异 ;不同孵出顺序雏鸟早期 (≤ 5d)发育无差异 ,之后差异显著 ,第 4出壳的雏鸟发育水平和成活率较低 ,而第 5出壳的雏鸟最低 ;亲鸟在产卵期的孵化是非连续的 ,而产卵结束后相对连续。如此 ,可以调节孵化时间 ,进而调控异步孵化的程度 ,使雏鸟在生长阶段形成适当的等级差别 ,以获得最大的繁殖收益。Data on breeding of Little egrets (Egretta garzetta) were collected in a period from March to July of 2001 at Jiyu Island in Xiamen Egret Natural Reserve.Eggs and nestlings were marked with colors for identifying the egg-laying and hatchling sequences.Ninety one percent of clutch sizes were 4 and 5,the laying period was 7.0±1.9?d,and hatching spread was 4.2±1.4?d;the incubation time was negatively correlated with the laid order of eggs;the mass was not different for the eggs laid early or late;at early stage of development (≤5?d),nestlings were not different in growth,but a significant difference appeared after then,the rate of growth and survival was the lowest for the 5th hatchling,and the second for the 4th when counting backwards.Incubation was not continuous in laying period,and became relatively continuous after that period.By this way,the parents may regulate the incubation time,and further adjust the asynchronism of incubation,resulting in a dominance hierarchy among the nestlings,which would maximize the reproductive success.福建省自然科学基金资助项目 (D9910 0 0 3 );; 厦门市环境保护科研所资助项
