摘要
1994~ 1998年对夜鹭繁殖习性与生长发育进行了研究。夜鹭于 4月中下旬迁到浙江 ,9月下旬、10月初迁离 ,居留期 165天。巢距地高 8 5 1m。平均窝卵 3 4 9枚 ,孵卵期 2 2~ 2 6天 ,育雏期 3 0~ 3 5天。年繁殖力3 5 0只。雏鸟体重生长模型为 :Wt =5 601+e-0 2 31(t-12 ) (R2 =0 99) ;体长、体重关系式为 :W =0 0 0 0 2 4 6L2 50 2 9。雏鸟体温发育分为 3个时期 :①紊乱期 ( 1~ 16天 ) ;②上升期 ( 17~ 2 8天 ) ;③稳定期 ( 2 8天以后 )。食性为螯虾( 4 5 % ) ;鲫鱼、草鱼、麦穗鱼 ( 4 0 % ) ;泥鳅 ( 15 % )。
From 1994 to 1998,observations on the breeding habits and growth of the nestling of black crowned heron were made in the Changshan and Yuhang Bird Reserve,Zhejiang Province.The results were as following:①The adults migrated to this reserve in the middle and late April and lefted in the late September.②Average height of nests from grownd was 8 51?m and the nests were simple,dash shapped with following measurements:external diameter 30-50?cm,internal diameter 20-30?cm,depth 3 5-8 0?cm.③The average number of egg of 35 clutches was 3 49,the incubation period 22-26 days,the survival rate in incubation period 95 45%,the length of nursing period about 30-35 days.④The body weight of the nesting was 26 8?g at the 1st day of hatching,and increases to a maximun of 556?g at the 51?th day.The growth of weight in 51 days after birth was fitted by thefollowingmodel:W t=5601+ e -0 231(t-12) with R 2=0 99.The length weight relationship could be expres sedinthefollowingformula: W =0 000246 L 2 5029 ⑤The process of establishment of homeothermal ability involved 3 periods:(i)the confused growth period (1-16 day);(ii)the growth period (17-28 day);(iii)the homeothermal period (after 28 day).⑥The main food of nestlings is Cambaroides (45%),Cyprinidae (40%),Cobitaidae (15%).
基金
中国野生动物保护协会资助项目
浙江省教委资助项目
关键词
夜鹭
繁殖习性
生长
食性
发育
恒温机制
Nycticorax nycticorax
Breeding habits
Growth
Development of homeothermal ability
Food composition