灰背鸫（Turdus hortulorum）隶属于雀形目鸫科鸫属，无亚种分化。在我国广泛分布，除西藏、宁夏、青海外，见于各省。于2014年4-9月在吉林省永吉县大岗子林场对灰背鸫的繁殖生态进行研究。灰背鸫为夏候鸟，每年4月下旬开始繁殖，至8月初结束，繁殖期近4个月。2014年共发现和监测78个灰背鸫巢。灰背鸫营开放性巢，巢呈碗状，雌雄鸟共同筑巢，筑巢期4-5d。巢外壁由枯草茎、细软的枝条、藤秧等混以泥土制成，内壁由细软枝条和草根等构成。巢高2.32±1.08m （n=70）；巢外径（121.43±8.15）mm×（116.99±9.40）mm （n=66）；巢内径（89.75±9.32）mm×（85.86±9.87）mm （n=66）；巢深（57.03±5.46）mm （n=66）。存在由前一年旧巢的基础上改造成新巢的现象。在发现的14种营巢树种中，占前四位的分别是山楂（Crataegus pinnatifida Bunge）（20%，n=14）、春榆（Ulmus davidiana Planch）（15.7%，n=11）、茶条槭（Acer ginnala Maxim）（14.3%，n=10）和山梨（Pyrus ussuriensis Maxim）（11.4%，n=8）。产卵时间多为每日上午7-11点。窝卵数为4～6枚，平均窝卵数为4.81±0.67（n=64）。卵鲜重为5.22±0.51g（n=223），卵体积为5.22±0.54cm3 （n=223），卵长径为27.04±1.33mm（n=223），卵短径为19.43±0.79mm（n=223）。卵鲜重随产卵次序显著增加(P﹤0.01)。雌鸟产首枚卵后即开始孵卵，孵卵期为13.33±0.49d（n=15）。雄鸟在附近警戒和情饲。雏鸟在1-3d内全部孵化出，孵化率为95.59%（n=136）。雏鸟孵化出的卵壳，较大的部分被亲鸟及时清理，较小的部分则直接吃掉。自动温度记录仪测得孵卵期巢内的平均温度为32.62℃，孵卵期雌鸟平均日离巢次数为12.82次；平均单次离巢时间为12.87min；平均在巢率为83.58%。灰背鸫雏鸟为晚成鸟。雌雄鸟共同育雏，育雏期为12天，饲喂的主要食物有蚯蚓、蝗虫、蚂蚁、小型的蛙类和鳞翅目幼虫等。同一窝中的雏鸟在1～2d内离巢。雏鸟出飞率为87.91%（n=21）。雏鸟的7项身体指标都能很好的被二元logistic方程拟合，拟合度均大于0.9。灰背鸫的日存活率（DSR）为0.9503±0.0072（95% CI:0.9341-0.9627），繁殖成功率为24.1%。导致繁殖失败的原因有天敌捕食、人为破坏捡拾、亲鸟弃巢和暴风雨破坏。其中天敌的破坏捕食占失败巢的88%，是导致灰背鸫繁殖失败的最主要原因。通过红外相机监测和被捕食巢的痕迹分析，发现主要捕食者为以黄喉貂（Martes flavigula）、西伯利亚花鼠（Eutamiassibiricus）和岩松鼠（Sciurotamias davidianus Milne）为代表的小型哺乳动物。通过对成功巢与被捕食巢共23个生境参数进行主成分分析的结果显示乔木和灌木密度比较高，枯树桩数量少的生境中，巢繁殖成功率高。

The Grey-backed Thrush (Turdus hortulorum) is a species of bird without sub-species in Passeriforme,Turdidae,Thrush, every year reproducting in eastern Siberia and northeast China region, wintering in southern China such as Guangdong and Guangxi, and widely distributed in China, except Tibet, Ningxia and Qinghai. In breeding season, the Grey-backed Thrush nests are located in shrubs or small trees close to the road, and commonly shrub density is higher, herb height and coverage is low. From April to September in 2014 the Grey-backed Thrush breeding ecology was studied in Dagangzi Forest Farm YongJi County Jilin province.The Grey-backed Thrush is a summer resident bird in Northeast China, whose resident period in breeding place is almost 4 months from the early April to the end of July annually. Seventy-eight nests of the Grey-backed Thrush were found in 2014. Both males and females participated in nidification. Its outer wall was made up of straw, twig, vine, mud and inner wall made up of soft branches and grass root. The height, outer diameter, inside diameter and depth are 2.32±1.08m（n=70）,（121.43±8.15）mm×（116.99±9.40）mm（n=66）,（89.75±9.32）mm×（85.86±9.87）mm（n=66）and （57.03±5.46）mm（n=66）resprctively. Some nests were built on the basis of the old ones. In 14 nest tree species were found, the four high proportion nest tree species are Maybush ( Crataegus pinnatifida )（20% n=14）, Keyco ( Ulmus japonica)（15.7% n=11）, Amur maple (Acer ginnala Maxim.)（14.3% n=10）, Sorb ( pyrus ussuriensis ) （11.4% n=8）.The Grey-backed Thrush lay one egg 7 ~ 11 o 'clock in the morning daily. Clutch size is 4～6 and the average clutch size is 4.81±0.67(n=64). The analysis of 223 eggs suggested that the mean egg weight, the mean egg volume, the mean egg length and the mean egg width were（5.22±0.51）g,（5.22±0.54）cm3,（27.04±1.33）mm and（19.43±0.79）mm respectively. Egg weight increase significantly with the order (P﹤0.01).The incubation period beginning with the first egg laid lasts（13.33±0.49）d（n=15）.Males only take the duty of vigilance and feeding around the nest. A single clutch of nestlings hatch within 1~3d, the average hatching rate was 95.59%（n=136）.Parents clear egg shell fragments by carrying off big ones and eating small ones. According to the Automatic temperature recorder, during the incubation period, the average temperature of inner nest was 32.62 ℃, The average times of the females leaving the nest is 12.82 times per day, and the average of single leaving time is 12.87 min, staying is 83.58% on average. The Grey-backed Thrush nestling is an altrice bird. Both female and male feed the nestlings. The Food included earthworms, locusts, small frogs and lepidoptera larvae. Nestling period was about 12 days. The nestlings leave the nests within 1~2 days and the fledging success is 87.91%（n=21).Daily survival rates（DSR）of the Grey-backed Thrush was 0.9503±0.0072（95% CI:0.9341-0.9627) and its reproduction success is 24.1%. The cause of the reproductive failure were nest predation, human-destruction, nests abandoned and bad weather. Nest predation was the main cause of nest failure, which accounted for 88% of all nest failures. By using infrared cameras monitoring and prey trace analysis,the main predators were Yellow -throat Mink, Siberian Chipmunks and Rock Squirrels. The principal component analysis of 23 habitat parameters on the successful and failed nests showed that the higher density of macrophanerophytes, shrub density and lower of stump were important habitat variables.