Abstract:

The sustained reproduction is an important landmark of successful adaptation of reintroduced species to climate recovery in the original extinction area. The study of synchronous population reproduction before and after reintroduction can provide accurate breeding prediction information and scientific basis for reintroduction managers. In this paper, we collected the birthing data of the reintroduced Père David’s deer population in Beijing in 1987, 1997, 2007, and 2017. The earliest birthing day of each year was used as a baseline to evaluate the delay in birth of reintroduced individuals and to measure the synchronization rate. ANOVA was used to analyze the effects of temperature, precipitation, air humidity, and light on the birthing timing pattern of reintroduced Père David’s deer. The results showed that, (1) After reintroduction, the annual birth rhythm of the population initially oscillated, then gradually reverted, and finally remained in a relatively stable state. After 85 years (from extinction to reintroduction), the first birthing of the new population in Beijing was delayed by 35 ? 42 days compared with that of Woburn Abbey population. Reintroduction of colonization stage: the birth rhythm of the new population was advanced annually. Population propagation stage: the rhythm of birth was delayed annually. Population recovery stage: the rhythm of birth was re-back slightly year by year and finally remained stable. (2) Deer parturition has more intense periodic timing and synchronization. In the first year after reintroduction, it took 18, 14, and 5 days to achieve 0 ? 25%, 25% ? 50%, and 50% ? 75% of the delivery rate, respectively. The relocation stage, it took 41, 19, and 11 days to achieve the rate of synchronization 0 ? 25%, 25% ? 50% to 50% ? 75%, respectively. In the re-expanding population stage, it took 45, 10, and 9 days to achieve the rate of synchronization 0 ? 25%, 25% ? 50% to 50% ? 75%, respectively. In the restoration phase, it took 24, 20, and 11 days to achieve the rate of synchronization 0 ? 25%, 25% ? 50% to 50% ? 75%, respectively.(3) Cumulative light and accumulated temperature had significant effects on the birth initiation of Père David’s deer but had no relationship with the birth synchronization. The delivery began when the accumulated temperature reached (2748.34 ± 157.69) ℃ and the accumulated light reached (3684.77 ± 514.26) h. (4) There was a correlation between the peak period of birth and aboveground biomass per unit area of reintroduced land. Judging by the rhythm of birth data, the new population has adapted to the climate of the reintroduction site. The number of non-synchronous birth individuals increased annually, but the total span of the delivery period did not extend. Since 1997, the population has had a 30% non-synchronous delivery average year. Therefore, analysis based on birth data reveals that after 37 years of reintroduction, the new population has recovered its adaptation to the habitation where it went extinct 120 years ago.

Key words: Reintroduce biology, Père David’s deer (Elaphurus davidianus), Propagation prediction, Rhythm of birth, Timing and synchrony

摘要：

种群持续繁殖是重引入物种对原灭绝地气候成功恢复适应的重要标志，研究重引入前后种群的繁殖波动规律，可为重引入管理者提供精准的繁殖预测信息和科学依据。本文整理北京重引入麋鹿种群后的1987年、1997年、2007年和2017年的总分娩数据，以每年最早分娩日作参照基准，统计个体分娩距此的天数，计算同步化率，并用ANOVA分析气温、降水、空气湿度、光照等变量对麋鹿分娩定时格局的影响。结果表明：(1) 引入后麋鹿种群年分娩节律呈“钟摆样”前后摆动，后逐渐回调，并最终处于相对稳定状态：时隔85年 (从灭绝至重引入) 后，北京麋鹿种群首次分娩时间较乌邦寺种群推迟35 ~ 42 d；重引入定植阶段：分娩节律逐年提前；种群扩繁阶段：分娩节律逐年向后推迟；种群复壮阶段：分娩节律又逐年微回调并最终处于稳定状态。(2) 北京麋鹿种群分娩有较强光周期定时和同步化：在重引入的第一年，分娩同步化率达到0 ~ 25%、25% ~ 50%、50% ~ 75%，分别用时18 d、14 d、5 d；重引入定植阶段分别用时41 d、19 d、11 d；种群扩繁阶段分别用时45 d、10 d、9 d；种群复壮阶段分别用时34 d、20 d和11 d。(3) 累积光照和积温，对北京麋鹿种群正常分娩启动影响差异极显著，对同步化分娩没有影响：妊娠期积温达到 (2748.34 ± 157.69)℃，累计光照达到 (3684.77 ± 514.26) h可启动正常分娩。(4) 北京麋鹿种群的分娩峰期与地上生物量峰期相关；从分娩时间来看，北京麋鹿种群已经恢复了对原灭绝地气候的适应。(5) 随时间增长，北京麋鹿种群非同步化分娩的个体数量逐年增加，分娩期总跨度并未延长。1997年以来，平均每年有30%左右的非同步化分娩现象。因此，基于分娩数据分析表明，麋鹿引入北京37年后，种群已经恢复对原灭绝地环境的重适应。

关键词: 重引入生物学, 麋鹿, 繁殖预测, 分娩节律, 定时及同步化