| 摘要: |
| 鉴于池塘养殖条件下三疣梭子蟹（Portunus trituberculatus）种内相残现象严重，螯足缺失率较高之实际。本研究对三疣梭子蟹的螯足进行了缺失处理，设置了无螯组（C0）、1螯足组（C1）和2螯足组（C2），在实验室内食物资源不足条件下，探讨了螯足数量（螯足缺失）对三疣梭子蟹摄食行为和竞食能力的影响。结果表明：（1）螯足数量对三疣梭子蟹的索食时间无显著影响（P>0.05）；（2）缺失螯足（C1，C2组）的三疣梭子蟹均可正常摄食，其中C0组蟹可用第一步足代替螯足抱持食物，将食物送入口中，表现出明显的行为补偿策略，但其啃食速度较慢，啃食耗时是C2组蟹的2倍；（3）C0、C1、C2组三疣梭子蟹均有部分个体同时抢占2份食物，其比率与个体具有的螯足数量有关，螯足越多，同时抢占2份食物的比率越高，其中C2组中有20%个体同时抢占了2份食物，而C0组仅有3%个体同时抢占了2份食物；（4）从螯足数量不同的三疣梭子蟹遭同类抢食的次数、比率来看，螯足数量越多的三疣梭子蟹，抢食欲望、抢食能力越强，而且更趋向向双螯均缺失个体发起抢夺性攻击，表现出明显的“强欺弱”现象；（5）螯足缺失直接影响了三疣梭子蟹对食物的保护，其中C0组中50%个体持有的食物可被同类抢走。整体上，缺失单个螯足对三疣梭子蟹摄食和竞食行为的影响不大，而缺失双螯将严重影响了三疣梭子蟹的摄食和竞食能力。 |
| 关键词: 三疣梭子蟹 螯足 数量 摄食 竞争 |
| DOI：10.11693/hyhz20161200291 |
| 分类号:Q958.12 |
| 基金项目:浙江省科技厅计划项目，2016F50042号，2015F10001号，2015F30003号；浙江海洋大学博士启动基金，22135010815号；舟山市普陀区科技计划项目，2015YN209号。 |
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| THE EFFECTS OF NUMBER OF CHELIPED ON THE ABILITY OF FEEDING AND THE COMPETITION FOR FOOD OF SWIMMING CRAB PORTUNUS TRITUBERCULATUS |
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HE Jie, WANG Xu-Jie, YU Fang-Ping, XU Wen-Jun, XIE Jian-Jun, WANG Geng-Shen, WANG Wei, SHI Hui
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Marine and Fisheries Research Institute of Zhejiang Province, Key Laboratory of Marine Culture and Enhancement of Zhejiang Province, Marine and Fishery Research Institute of Zhejiang Ocean University, Zhoushan 316021, China
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| Abstract: |
| Cannibalism and cheliped deficiencies of swimming crab Portunus trituberculatus when cultured commercially is widely acknowledged as a serious phenomenon, however, no scientific data exist in the public domain about the effect of cheliped deficiencies on the feeding behavior and aggression of P. trituberculatus in this phenomenon. Therefore, this study was designed to explored the ability of feeding and the competition for food of P. trituberculatus with both, single and without any cheliped (C2, C1 and C0) under the condition of insufficient food in the laboratory, and the results showed that:No significant effect were detected in the time of searching food when the swimming crab lost cheliped (P>0.05). The crabs of C0 could use the first walking legs instead of chelipeds to held food, which showed the strategy of behavior compensation, but they had significantly longer feeding time than uninjured individuals. No matter the injured or uninjured crabs, some of them could took two copies of food at the same time, and the proportion was associated with the number of missing chelipeds, the more loss of cheliped, the lower the proportion of taking two copies food, such as 20% individuals of C2 took up two copies food, while only about 3% individuals in C0. The proportion and frequency of competition for food exhibited that the individual which owned more chelipeds had a stronger competition desire and were inclined to compete for food with cheliped-lost individuals. Cheliped lose has direct affected the protection of P. trituberculatus for food, the 50% individuals of C0 lost the food. On the whole, the lack of single cheliped had little effect on the feeding and feeding behavior, while the absence of 2 chelipeds will seriously affect the feeding ability of P. trituberculatus. |
| Key words: Portunus trituberculatus cheliped number feeding competition |
