黄河三角洲是东方白鹳的迁徙停歇地之一,但近些年开始出现繁殖种群.为了解该种群的繁殖现状,有效开展保护工作,于2009年在黄河三角洲对东方白鹳的繁殖生态进行了研究.2009年在黄河三角洲繁殖的东方白鹳种群数量为21对,繁殖个体于2月上旬陆续返回繁殖区,最早于2月21开始筑巢.巢筑于水泥电线杆、人工招引巢或者高压输电铁塔上,其中利用旧巢11巢,新建巢10巢.大汶流巢区平均巢高13.25 m±2.07 m(N=18)、巢间距647.22 m±1 086.49 m(N=18);黄河口巢区平均巢高25.50 m±7.97 m(N=3),巢间距42 640.00 m±62 838.80 m(N=3).孵化期最早始于2月25日,个别繁殖对受干扰影响延迟到5月中旬.孵化期32.07 d±1.34 d(N=15),育雏期63.33 d±6.83 d(N=12),日育雏6.23±2.23次(N=68),雏鸟最早离巢时间为5月28日,最晚离巢时间为8月19日.2009年的21对繁殖东方白鹳共有17对繁殖成功,孵出47只幼鸟,出飞幼鸟37只.影响东方白鹳繁殖的主要因素是强风,此外,游客干扰、适宜巢址缺乏也是影响繁殖的重要因素.为提高人工招引繁殖的成功率,可适当增加人工招引巢数量并对其上的巢基进行加固.
The Yellow River Delta is an important stopover site of the oriental white storks(Ciconia boyciana) in China.In order to collect the breeding data of C.boyciana for its effective conservation of the population,we observed the breeding habits of the birds in the Yellow River Delta.A total of 21 pairs of C.boyciana were found breeding there in 2009.The birds chose the nest sites in early February,and began to build nests in mid-late February.Nests were built on wire poles,artificial nests and pylons.In Dawenliu,the average height of nests was 13.25 m ± 2.07 m(N = 18),and the distance between nests was 647.22 m ± 1 086.49 m(N = 18).In Huanghekou,the height was 25.50 m ± 7.97 m(N = 3),and the distance between nests was 42 640.00 m ± 62 838.80 m(N = 3).The earliest hatching began on February 25,but the disturbed breeding pairs postponed their hatching to mid-May.The hatching period lasted for 33.23 d ± 1.36 d,and parental care for 63.33 d ± 6.83 d(N = 12).Parents fed their nestlings for 6.23 ± 2.23 times(N = 68) every day.The nestlings left their nests early on May 28 and late up to August 19.Only 17 pairs of the 21 breeding pairs made their hatching successful with 47 baby birds coming out from eggs and 37 nestlings surviving to fledging.Strong wind was the major factor affecting their breeding.In addition,the disturbance by visitors and lack of suitable nest sites also influenced the breeding.In order to increase the breeding rate of the stopover population,it is necessary to provide more artificial nests and solidate the nests.