Nestling Growth Of The Yellow-rumped Flycatchers (Ficedula Zanthopygia)

The nestling growth period plays an important role in the whole life history of the avian.This period has a close connection with population dynamics, relationship of varieties,community structure and functions in the ecosystem, determining an individual life span and survival rate of species. The study on nestling growth and brood size of the Yellow-rumped Flycatchers(Ficedula zanthopygia) was carried out in secondary-forest of Zuojia nature protection area in Jilin Province from March to July in 2014-2015.In this study, 500 nest-boxes were monitored. We found 58 nests of Yellow-rumped Flycatcher in total, 48 of which bred successfully; the average clutch size was 6.16±0.71 and the breedingsuccess ratio was 82.76 %. The data of 232 nestlings’ beak length, tarsometatarsus length, wing length, body length, and avoirdupois were collected and simulated by the logistic model.The results showed that the beak and tarsometatarsus grew fast at early stage. The growth of tarsometatarsus and avoirdupois were at a high degree of completion. The development of wings and body delayed due to the late development of feather. The ratio of tarsometatarsus and avoirdupois of nestling at the post-fledging period to adults were 100.29% and 103.11%respectively. The growth of avoirdupois was ahead of rest organs at the early stage which was consistent with the hypothesis of energy distribution. The results also indicated that with of different brood size the beak length of the nestlings at 5.5-days-old(P=0.026<0.05) and10.5-days-old(P=0.044<0.05) was significant. There was significant negative correlation between beak length of post-fledging period and brood size(P=0.046<0.05). The growth rate of beak length and brood size had significant positive correlation. Therefore, we conclude that the difference of brood size gives rise to competition in food begging, which affects brood size directly. All parameters of the five organs illustrated that when brood size was 6, the growth rate of avoirdupois and daily gain achieved maximum. This result of research also proves Lack’s hypothesis that the nest with common brood size shows the highest productivity.