Abstract: Low temperature affects the growth, metabolism, and living status of birds. Birds can change their behavior to adapt to changing temperature. Crested Ibis (Nipponia nippon) is an endangered species endemic to East Asia, which was introduced to Beidaihe of Hebei Province from Yangxian of Shaanxi Province to establish the world’s highest-latitude acclimation population. In this study, we analyzed the effects of season and temperature on the rest behavior of Crested Ibis in Beidaihe and Yangxian. The doublelegstand with bill out (DO) was the most common rest behavior in wandering period (70.9%). However, the proportion of DO decreased significantly in wintering period (55.6%), while the proportion of onelegstand with bill out (OO) and bill tuck increased correspondingly. Temperature significantly affected the behavior of double leg stand with bill tuck (DT), OO and onelegstand with bill tuck (OT). Therefore, CrestedIbis adapted to low temperature by increasing the proportion of protecting exposed parts in winter. In winter, the proportion of groveling on branch of nocturnal roost tree increased with decreasing temperature, but this behavior was not observed in daytime. This suggested that groveling might be a response of Crested Ibis to the extremely tolerable low-temperature, which should arouse vigiance in protection monitoring. Crested Ibis seldom used the shelters in the acclimation cage in winter, indicating they could adapt to temperature as low as -20 ℃. To ensure the safe wintering of Crested Ibis, we suggest that more evergreen trees such as Pinaceae are needed to provide optimalnocturnal roost habitat, and that using wind barrier using straws to reduce the negative effect of strong wind at night in the acclimation cage.

Key words: Crested Ibis (Nipponia nippon), Beidaihe, low temperature, behavioral response.