宽鳍鱲个性与维持代谢、食物占有能力和日常能量消耗的关联

为了探讨集群性鱼类宽鳍鱲(Zacco platypus)的个性在群体中的生态学关联, 研究首先测定了宽鳍鱲的个性特征(包括活跃性、探索性、勇敢性和社会性)和标准代谢率。随后在群体(10个群体, 每群体6尾鱼)条件下测定了每尾鱼的运动轨迹、摄食状况, 并计算出每尾鱼的日总耗能。研究发现: 宽鳍鱲的个性特征与标准代谢率、摄食率和日总耗能均没有关联。个性与摄食率的关联丧失可能因为其野外生境食物丰度较高, 个性的差异未体现在对食物的竞争能力上; 而个性与能量代谢无关联可能与实验室单尾鱼测定条件下宽鳍鱲的应激反应有关。日总耗能与集群运动参数中的运动时间比、平均游泳速度和摄食率均呈正相关, 可能因为运动能耗和消化能耗在日总耗能中占比较高。另外, 日总耗能也与距质心距离正相关, 可能个性较积极的个体在群体中活跃程度较高, 集群时较多位于群体的边缘, 且日常能量消耗较高。研究结果表明, 集群时活跃的成员往往处于鱼群的外周, 食物占有能力更高, 但日常能量消耗也越多。研究还提示针对集群性野生鱼类, 可能在群体条件下考察其个性、能量代谢特征及其生态收益和代价更具生态学意义。

THE RELATIONSHIPS BETWEEN PERSONALITY AND MAINTENANCE METABOLISM,FOOD INTAKE RATE AND DAILY ENERGY EXPENDITURE IN ZACCO PLATYPUS

The individual difference of behavior in fish species is defined as personality. It has been found that fish exhibit personality which might remain to some extend when join a group. However, the ecological relevance of withholding of personality, i.e. individuality during shoaling has not been investigated. To study the ecological relevance of individuality and traditionally measured personality traits in a group living fish species, we first measured standard metabolic rate (for estimation of maintenance metabolism, SMR), personality traits of activity, exploration, boldness and sociability of pale chub (Zacco platypus) of the fish that were grouped randomly into shoal of six individuals. SMR, feeding rate and daily energy expenditure (DEE) had no relationship with any personality variables. The lack of correlation between personality and feeding rate may be due to the high food abundance of pale chub in the wild, and the personality is not reflected in the competition for food. The relationship between personality and metabolism was not found. The DEE was positively correlated with percent time moving, average swimming speed and the feeding rate within the shoal. In addition, the DEE was also positively correlated with the distance to centroid. The results suggest that, it may be more ecologically meaningful to investigate their personality traits within the shoal using group living wild fish.