中华绒螯蟹幼蟹温度选择与偏好研究

研究通过利用自动化的电子穿梭系统研究长江野生中华绒螯蟹幼蟹的行为参数对温度变化的响应, 进行了Ⅰ组8℃和14℃实验组、Ⅱ组14℃和21℃实验组、Ⅲ组21℃和28℃实验组、Ⅳ组28℃和35℃实验组共4个实验组。实验表明中华绒螯蟹幼蟹的最佳偏好温度在28℃。幼蟹会加速逃离不适温度区域, 且偏离温度越高游泳速率越高, 温度和游泳速率拟合方程: y=0.0027x2–0.1045x+1.5875, R2=0.8615, 昼夜(P>0.05)和雌雄性别(P>0.05)差异对温度的偏好选择未见明显影响。研究为中华绒螯蟹养殖、利用及野外环境下种群保护与调控管理提供科学依据。

TEMPERATURE SELECTION AND PREFERENCE OF JUVENILE ERIOCHEIR SINENSIS

Chinese mitten crabs are widely distributed from Fujian in southern China to Liaoning in northern China, and they are able to adapt to a range of temperatures. The study focused on the behavioral responses of juvenile mitten crabs sampled from the Yangtze River to changes in water temperature. This is an important stage of the life cycle of this species that often has low disease resistance and high mortality rates. A temperature gradient was established across the shuttlebox to enable the preference of juvenile crabs for either temperature to be established. The shuttlebox system ensures the stability of the temperature on either side of the box. Established experimental groups were set as follws: Group Ⅰ (8℃ and 14℃), Group Ⅱ (14℃ and 21℃), Group Ⅲ (21℃ and 28℃), and Group Ⅳ (28℃ and 35℃). Results showed that the juvenile Chinese mitten crab had a preferred temperature (T_pref) of 28℃. Neither time of day nor gender had any significant effects on the temperature preference. Further more, there were significant differences in the swimming velocity of the juvenile crabs in different groups under the same experimental temperatures. The juvenile crabs increased their swimming velocity to escape suboptimal water temperature, and there was a positive relationship between swimming velocity and the degree of temperature deviation from T_pref. Water temperature with an inverted U-shaped swimming parabolic rate. The fitting equation for temperature (x) and swimming velocity (y), y=0.0027x2–0.1045x+1.5875, R2=0.8615. The impact of gender differences in swimming speed was not significant (P>0.05), and there was no significant difference between day and night swimming rate (P>0.05). Thus, the results of this study will be useful for enhancing the survival and growth rates of this species in aquaculture settings as well as for controlling and protecting them in the wild.