朱鹮野化种群对冬季低温的行为响应

低温对鸟类的生长发育、新陈代谢和生活状态有显著的影响,鸟类往往通过改变行为模式来适应温度的变化。朱鹮(Nipponia nippon)是东亚特有的濒危鸟类,2018年从秦岭南麓的陕西洋县引入到河北北戴河,建立了全球纬度最高的野化种群。本文以北戴河和洋县两个野化种群为研究对象,采用瞬时扫描法观察分析了季节和温度等因素对朱鹮休息行为的影响。结果表明,双腿站立露喙是朱鹮在游荡期最常见的休息行为(70.9%),但在越冬期显著降低(55.6%),而单腿站立和隐喙行为比例相应升高。温度对双腿站立隐喙、单腿站立露喙和单腿站立隐喙3种行为的比例有显著影响。可见,朱鹮在冬季通过增加保护裸露部位的行为比例来适应低温。在冬季,随着温度的下降,朱鹮趴卧在树干上的夜宿行为比例逐渐增加,而这一行为在白天没有记录到。温度对成鸟和幼鸟冬季的休息行为有显著影响。由此表明,趴卧行为很可能是朱鹮对极端耐受低温的一种应对,在保护监测过程中需警惕。朱鹮在北戴河越冬过程中没有使用网笼中的遮挡伞棚和庇护场所,表明其能够自主适应-20℃的低温。为了确保野化朱鹮顺利越冬,建议在野化网笼中增加一些松科等常绿树种,为朱鹮提供更加优良的夜宿环境,并用稻草搭建风挡,减少夜间大风的负面影响。

Behavioral responses of Crested Ibis(Nipponia nippon)to low temperature in winter

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 doubleleg-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 vigilance 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.