旅游干扰下水质对大鲵繁殖行为与繁殖力的影响

通过控制大鲵仿生态繁育池进水量模拟旅游干扰下的水质溶解氧特征,采用红外数字监控系统研究大鲵繁殖行为(产卵与护卵)及繁殖力(相对产卵量、受精率与孵化率)特点,分析它们与水质的关系,探讨旅游干扰导致的水质变化对大鲵繁殖行为及繁殖力的影响。结果表明: 与对照组相比,旅游干扰下大鲵的产卵行为与繁殖力未受到显著影响,但雄鲵护卵行为中的扇尾与搅动时间显著延长,以提高水中溶解氧浓度,满足大鲵胚胎发育需求;此外,旅游干扰下受精卵的孵化时间显著延长,但孵化率未受到显著影响。雄鲵护卵行为变化与受精卵孵化时间延长可能是大鲵对旅游干扰导致的水质变化的一种主动响应。

Effects of water quality on the reproductive behavior and capacity of Andrias davidianus under tourism disturbance.

Water quality under tourism disturbance was simulated through controlling the water intake of the ecological breeding ponds of Chinese giant salamander (Andrias davidianus, CGS). Both the reproductive behavior (oviposition and parental care) and capacity (relative egg production, fertilizing rate of eggs, and hatching rate of fertilized eggs) of CGS were examined using a real-time infrared digital monitoring system. The relationships among reproductive behavior, capacity, and the corresponding parameters of water quality were analyzed, to understand how water quality under tourism disturbance would affect the reproductive behavior and capacity of CGS. The examined oviposition behavior and capacity of CGS showed no variation in general, but the parental care behavior such as tail fanning and agitation time of the male CGS were prolonged significantly in the groups under tourism disturbance. Such prolonged behaviors would help increase the content of dissolved oxygen (DO) to meet the high demands of DO during embryonic development of CGS. In addition, the overall hatching time of fertilized eggs was increased significantly under disturbance conditions when it compared with the control, which would ensure the overall hatching rate among these comparative groups unaffected. In summary, the prolongations of some reproductive behavior (tail fanning and agitation of the male CGS and the development time of fertilized egg) would be a kind of positive actions of CGS in response to the changes of water quality resulted from tourism disturbance.