野生扬子鳄冬眠实况两例

Deep Brumation Features of Zhejiang Chinese Alligators

2015年1月,在对浙江省长兴尹家边扬子鳄自然保护区的栖息地进行改造时,挖掘到了两条处于深度冬眠时期的扬子鳄,于是我们在仔细勘测了冬眠洞穴的实况及冬眠扬子鳄的相关行为表现后,对此两例野生扬子鳄之冬眠实况进行报导。本研究发现其中一条是雌性成年鳄,其冬眠于大生态池的岸边,且冬眠洞穴呈宽畅的一字形。另外一条是雄性成年鳄,其冬眠于小生态池的中心岛上,且冬眠洞穴呈分叉的人字形。我们发现冬眠洞穴的洞口都较隐蔽,一般有植被遮掩,且洞口至少有一半浸于水面之下。而冬眠地道都是渐行渐深的坡度下行走向,因此,冬眠地道均浸泡于水中,且洞底是积水最深处,当我们挖到鳄鱼时,它们都卧于洞底最温暖的淤泥层上。虽然,两条鳄鱼的冬眠洞穴所处生态池大环境有所不同,但我们发现这两条处于深度冬眠时期的鳄鱼都具有一定的意识,遇到刺激后能表现明显的自卫反应,甚至会发出"吼-吼"的警告声。本研究揭示浙江扬子鳄在冬眠的行为上和冬眠洞穴的形态上与文献报导的安徽扬子鳄冬眠特征均不同,可能是两个种群已经出现了分化,因而冬眠特性迥然不同。因此,本研究的新发现将为扬子鳄的保护工程提供新的参考。

We collected two Zhejiang Chinese alligators(one adult female and one adult male) at the stage of deep brumation when we conducted habitat modification at the Changxing Yinjiabian Chinese Alligator Nature Reserve of Zhejiang Province,in winter 2014.We examined the burrow structures and recorded the following characteristics.The burrow entrance was covered by plants and its lower 1/2 or 2/3 part was under water.The underground tunnel took two shapes, '一' in the big ecological pool and '人' in the small ecological pond.The tunnel grew gradually deeper as it extended,and the alligators were brumating above the warm sludge layer at the bottom of the burrow.The two deeply brumating alligators showed obvious behavioral self-defense.This study indicates that the Zhejiang Chinese alligators are different from the Anhui Chinese alligators not only in burrow structure but also in brumation behavior,suggesting that the Zhejiang population might have been differentiated from the Anhui population.This study provides a new base for protecting the endangered Chinese alligator.