关键词: 海河流域, 水库, 沉积物, 重金属, 生态风险

Abstract: Many aquatic animals can release alarm cues to transmit warning when stressed by a predator. Recognizing the cues released from their conspecifics, aquatic animals will response with antipredation appropriately. Macrobrachium nipponense is a key and one of the most promising aquaculture species in China. Whether they can recognize their predator is important for their survival. In the present study, we used M. nipponense as a model species to explore whether it can recognize the alarm cues released by their conspecifics which have visually recognized by their shared alien predator Procambarus clarkii. Our results indicated that the number of M. nipponense (3.20±0.94,n=80) (mean±SD) in the experimental group trying to hide under the shelter was significantly higher than that in the control group (2.81±0.80,n=80) (repeated measures ANOVA: F_1,156=7.753, P=0.006). In the initial stage, the number of M. nipponense (28.90±21.19,n=40) crossing the midline in the experimental group was significantly lower than that of the control group (69.08±21.58,n=40) (Wilcoxon signed ranks test: Z=-5.498, P<0.01). In the final stage, the number of M. nipponense (19.93±12.44,n=40) crossing the midline in the experimental group was significantly lower than that of the control group (36.33±21.17,n=40) (paired t_tests: t₃₉=6.618, P<0.01). The results suggest that M. nipponense can detect alien predator cues released by their conspecifics, and have antipredation behaviors by increasing the usage of shelter and decreasing their activity level. We predict that M. nipponense will therefore increase its vigilance to predators and survival by recognizing its congener’s chemical cues.

Key words: Haihe River, reservoir, sediment, heavy metal, ecological risk.