青海湖鸬鹚繁殖习性的初步观察

Preliminary Observation on the Breeding Habits of Cormorant

1999年 4～ 7月和 2 0 0 0年 3～ 8月 ,对青海湖地区的鸬鹚繁殖过程进行了观察 ,初步掌握了鸬鹚的迁移、营巢、产卵、孵卵、育雏和扩散等生态习性。结果表明 :鸬鹚每年 3月中、下旬迁来青海湖繁殖 ,两性共同营巢 ,营巢期集中在每年 4月上旬至 6月中旬 ;产卵高峰期为 4月下旬至 5月中旬。平均卵重是(5 7 5± 2 0 2 )g ,卵的大小为 67 2 9mm× 40 2mm ,平均窝卵数为 (3 61± 0 3 4)枚。鸬鹚孵卵期为 (2 8 0 7±0 5 3 )d ,孵化期间的卵重损失 (Y)与孵卵天数 (X)之间的线性回归方程为Y =0 997-0 0 0 68X(r=0 990 ,df=8,P <0 0 1 )。

Breeding habits of Cormorant ( Phalacrocorax carbo) population were studied in the Qinghai Lake region. The paper reported the breeding habits such as nesting, egg laying, hatching, parental care and pervasion in the cormorants. The results showed that cormorants came to the Qinghai Lake in early and mid March. Breeding cormorants cooperated to build their nests from early April to mid June. Cormorants laid their eggs mainly during the first half of May. Average clutch size in cormorants was 3.61±0.34.The eggs weighed 57.5±2.02?g and were 67.29?mm×40.2?mm in size. Incubation period was 28.07±0.53 days. The relationship between egg weight loss and incubation time was described by the equation: Y =0.997-0.0068 X ( r =0.990, df =8, P <0.01), where Y was the egg weight loss during incubation, X was incubation time.