为研究克氏原螯虾在不同庇护所生境下的生长差异及其采取的不同生存策略,本实验在水池中设置洞穴、角落2种庇护所生境,并以无任何庇护所的水池为对照,饲养亚成体克氏原螯虾一个月.计算各组克氏原螯虾存活、生长的参数及耗饵量、转化率等摄食参数.实验结果表明,存活率指标以洞穴组最高,为84.0%,对照组最小,为22.0%;群体增重、个体增重和转化率指标均以角落组最高,分别为324.2g、10.3g、72.5%;群体耗饵量以对照组最小,为248.2g.本研究得出了不同庇护所生境对克氏原螯虾存活、摄食和生长影响显著的结论.洞穴遮蔽程度最大,能提供最大程度的保护,螯虾多藏匿在洞中,觅食和打斗行为较少,其采取的生存策略为更利于存活的相对保守型.角落的遮蔽程度较小,其觅食和打斗行为都较多,其采取的生存策略则为更利于生长的相对冒险型.
Procambarus clarkii is a species of aggressive animal with burrowing and typical social behavior.The purpose of the experiment is to find out the differences of crayfish's growth between different habitats and presume the differences in their living strategies.In the experiment,we set up two types of sheltered living condition for P.clarkii in the ponds including burrows and corners,and the control group without any shelter.After one month,we calculated the survival rate,total weight gain,individual weight gain.Meanwhile,we obtained data of feeding and residual bait,and their sum and the growth increment in weight so as to calculate total feed consumption and feed convert ratio.The results indicated that survival rate of the burrow group ranks the highest(84.0%),then the corner group(63.0%),and then the control group(22.0%).Concerning the total weight gain,individual weight gain and feed convert ratio,the corner group ranks the first,with significantly higher total weight gain(324.2g),feed convert ratio(72.5%) than the other two groups,significantly higher individual weight gain(10.3g) than the burrow group.Total feed consumption of the control group is the lowest(248.2g) and significantly lower than the other two groups between which there is no significant difference. Our study indicated that the habitats of shelter have significant effects on the survival,foraging and growth of P.clarkii.Burrow has the biggest cover area which can provide protection to the greatest degree.Hiden in the burrows P.clarkii live in a relative conservative way,foraging and fighting little,which is good for survival.On the contrary,the cover area of corner is not as big as burrow,crayfish are fighting each other for shelter,their foraging and fighting behaviors are more obvious,their living strategies is relatively more adventurous,which is good for growth.