摘要
大天鹅(Cygnus cygnus)每年3月底至4月中旬迁来新疆巴音布鲁克。4月下旬产卵。窝卵数(n=21)为5.05±1.40枚。最多8枚卵。卵为白色。鲜重(n=117)为337.50±32.60g,外径为(113.40±4.39)×(73.29±2.27)mm。雏鸟6月初出壳,到9月中旬始飞,10—11月南迁。因家族不同和年龄不同,天鹅嘴型变化较大。由此本文探讨和澄清了一些分类问题。
The Whooper Swans (Cygnus cygnus) arrived at nesting grounds of Bayinbuluke in Xinjiang from late March to middle April and the nesting period was generally from April to June in 1992. Most nests are often (?)aced in or near standing water, less often beside running water. A clutch from 3 to 8 eggs,most commonly 4 or 6 (X=5.05±±1.40,n=21),is laid. The fresh egg is white,av. 337.50±32.60g in weight and av. 113.40±4.39×73.29± 2. 27 mm in size (n=117). The female alone incubates,and the normal incubation period is 30 to 32 days. The rate growth is very slow,and the fledging period is from June to September more than 90 or 105 days old before they begin their thousand-mile southward migration from October to November. In the field the (?)xrensively yellow bill is an evident mark,but there are some variations in the bill pattern (?) different groups or different ages. We also study and clear up some classificatory mist(?)k (?) this paper.
出处
《干旱区研究》
CSCD
北大核心
1993年第2期46-51,共6页
Arid Zone Research
基金
国家自然科学基金(39170119)
关键词
大天鹅
繁殖
嘴型
新疆
Cygnus cygnus
breeding bill patic
Xinjiang
