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Predation is one of the most important extrinsic factors acting upon animal populations and is a strong selective force in the evolution of form and function. Understanding the impact of predation on bird population dynamics is crucial for understanding the predation pressure of bird populations and implementing conservation strategies, especially for threatened or endemic bird species. In this paper, we sorted the predation events in the wild Crested Ibis population in Yangxian County, Shaanxi Province, from 1981 to 2021 and in the reintroduced Crested Ibis population in Ningshan from 2008 to 2021. With the use of age‐classified Leslie matrix models to simulate Crested Ibis populations under different predation pressures, the random population growth rate was estimated, and the impact of predation on population dynamics was evaluated. The results showed that snakes and raptors were the main predators of Crested Ibis in the wild and reintroduced populations, and the number of dead individuals was unevenly distributed within the three age classes in both the wild population (df = 2, χ2 = 13.236, p < 0.05) and reintroduced population (df = 2, χ2 = 49.273, p < 0.01). Predation caused a reduction in the potential annual population growth rate of 2.37% (confidence interval [CI]: 2.29–2.45) in the wild population and 2.88% (CI: 2.82–2.94) in the reintroduced population. The overall average growth rates of the wild and reintroduced populations derived from population model simulations were 12.84 and 18.13%, respectively, which suggested that the wild and reintroduced populations was increasing under the current predation pressure and that the impact of predation on the population was acceptable and sustainable. [ABSTRACT FROM AUTHOR]

Post‐release dispersal of reintroduced animals refers to the process of successful colonization and failed settlement. To ensure the establishment and persistence of a reintroduced population, the impacts of different factors on the post‐release dispersal of captive‐bred animals must be assessed. In this article, we focused on two reintroduced Crested Ibis (Nipponia nippon) populations in Shaanxi Province, China. We applied multiple approaches to evaluate the effects of age, body weight, sex, timing of release, size of acclimatization cages for rewilding, and duration of acclimatization on the survival rate of released populations. The results showed that the survival capacity of released individuals was negatively correlated with their age in Ningshan County (Spearman, r = −0.344, p = 0.03, n = 41). The released ibises in Ningshan and Qianyang County had an average dispersal direction of 210.53° ± 40.54° (Rayleigh's z test: z = 7.881 > z0.05, p < 0.01, n = 13) and 27.05° ± 2.85° (Rayleigh's z test: z = 5.985 > z0.05, p < 0.01, n = 6), respectively, suggesting that the dispersal tended to clump in one direction in both sites. The MaxEnt modeling results indicated that the most significant environmental factor responsible for breeding site selection in Ningshan County was paddy field. In Qianyang County, precipitation affects nest site selection through influencing food availability. In conclusion, the evaluation framework used in this study can serve as an example for developing conservation priorities on the landscape scale for more animal reintroductions. [ABSTRACT FROM AUTHOR]