吉林省白城地区干草原栗斑腹的繁殖生态

Breeding Ecology of Jankowski′s Bunting in the Dry Grassland in Baicheng, Jilin Province

栗斑腹在吉林省为留鸟 ,一年可繁殖两次 ,其雏鸟为典型的晚成鸟。 4月末开始有求偶追逐和争雌行为 ,5月中旬产卵。雌雄鸟筑巢时间分别是 43 min/d和 3 6min/d(筑巢第 4天 )。平均窝卵数为 5 .0 9± 0 .5 8枚 /巢 (n=3 1 ) ,孵卵前、中、后期雌鸟孵卵占白天活动时间的 3 5 %、74.5 %和 67.6% ,孵化期为 1 2 d,孵化率为 3 6.3 % ,2、8日龄喂雏分别为 4.5次 /h和 9.0次 /h。雏鸟的体重及外部器官的发育除嘴峰外 ,生长曲线均符合 Logistic方程 ,而嘴峰长的生长近似直线 ,栗斑腹雏鸟生长发育体重的生长模型为 :W =1 4.95 /1 +(e- 0 .552 ( t- 3.6 3) ) ,雏鸟 1 1日龄后出飞 ,繁殖成活率为 2 7.7%。

This study was carried out at Dagang forestry farm in Baicheng region, Jilin Province, China (122°47′～124°04′E,45°28′～46°18′N ). The study sites, about 1000hm 2,are distributed in the farm, which is located at edge of Songnen Plain, ranging from 130m to 160m above sea level. The climate is featured as east monsoon climate having hot dry summers and cold snowy winters. Annual temperature is averaged 11℃, annual precipitation 395 1mm, and unfrosted days about 135d.The vegetation is dominated by various grasses. The Logistic equation was used to illustrate the relation between body weight and outer organs. Ricklefs' formula (1977, B=30 exp (1-P i ln P i)) was used to count breeding season length. Jankowski′s Bunting is resident in Jilin Province. The birds breed twice a year. According to our observation, the bird began to show mating behavior at the end of April,to incubate on the May first, and to achieve the peak of incubation from 22 to 23 of May; The female and male took 43min and 36min for incubation, respectively (the fourth day incubation). Inner radius length of the nest was 7 3±0 48cm, and breadth 6 34±0 54cm. The length of outer radius of the nest was 9 98±0 75cm and the breadth 8 60±0 97cm; the depth of nest was 5 42±0 69cm and height 4 73±0 82cm .In the middle of May, the bird began to lay eggs. Length of egg was18 97±0 74cm, breadth 14 98±0 50cm and the weight 2 12±0 24g( n =38). During the prophase,metaphase, and anaphase,the female spent 35%,74 5%, and 67 6% of daytime, respectively. The incubation period took approximately 12 days. Incubated rate was 36 3%. Two day old and eight day old nestlings were fed 4 5 and 9 times per hour, respectively. Nestling's body weight and outer organs' growth was well fitted into Logistic equation. The weight growth model fitted was:W=14.95/(1+e -0.552(t-3.63) ). The bird could fly in eleven days after its birth, and nestling survival rate was 27 7%.