红碱淖东方大苇莺繁殖生态

The Breeding Ecology of Oriental Great Reed Warbler ( Acrocephalus orientalis) in Hongjiannao of Shaanxi Province

2012年5～7月,在陕西红碱淖对东方大苇莺的繁殖生态进行了研究。结果表明,东方大苇莺5月末迁来繁殖,营巢于芦苇丛中,巢口向上呈深杯状,由枯芦苇和芦苇絮编织而成。对17个巢的巢参数进行了测量:巢外径(11.85±0.216)cm,巢内径(5.87±0.101)cm,巢深(6.49±0.166)cm。巢距地面高度(106.00±4.421)cm,约位于芦苇高度的2/5处。平均窝卵数(4.67±0.188)枚,卵重为(2.70±0.044)g,卵长径为(21.93±0.13)mm,卵短径为(15.81±0.06)mm。孵化期为(15～18)d,孵化率为78.8%,巢雏成活率为95.2%。雏鸟的体重、体长的生长符合Logistic曲线方程拟合。芦苇的高度和密度是制约东方大苇莺巢址选择的主要因素,恶劣天气和大杜鹃巢寄生是影响繁殖成效的主要原因。

The breeding ecology of oriental great reed warbler （Acrocephalus orientalis） in Hongjiannao of Shaanxi Prov- ince was studied from May to July in 2012. The results showed that the A. orientalis arrived at this breeding area in late May, and then nested on branches of reed. The cup-shaped nests were upward and consisting of wizened and feature reed. The parameters of 17 （17 out of 22 ） nests were measured in detail. The external and internal dimensions as well as depth of the nests were 11.85 cm ±0. 216 era, 5.87 cm ±0. 101 cm and 6.49 cm ±0. 166 cm, respectively. The nests were normally found in the lower part of reed （about 2/5 ） and the height above ground was 106. 00 cm ±4. 421 cm. Additionally, the av- erage clutch size was 4.67 ±0. 188. The weight, length and breadth of the eggs were approximately 2. 70 g ±0. 044 g, 21.93 mm ±0. 13 mm and 15.81 mm ±0.06 ram. The incubation period was frequently between 15 - 18 days, and the hatehability and survival rate of A. orientalis were 78.8% and 95.2%. The growth curves of weight and length of nestlings were corresponding with Logistic curves. Moreover, the nest-site selection was highly depended on the height and density of reed. Foul weather and nest parasitism of Eurasian cuckoo （ Cuculus canorus） were also important factors to affect the breed- ing success of A. orientalis.