摩洛哥南部沿岸沙丁鱼耳石与生长的关系

Relationship between otolith growth and shape of Sardina pilchardus in south coastal waters of Morocco

根据2011年6～8月我国资源探捕船在摩洛哥南部沿岸海域（21°00′～ 26°00′N、15°30′～ 20°00′W）采集的沙丁鱼（Sardina pilchardus）样本,测量其耳石的全长、宽度、背长、背宽、翼叶长和腹噱长,以此作为耳石的6个外部形态参数,利用方差分析研究性成熟和个体大小对耳石生长的影响.结果表明,除翼叶长外,左右耳石的其它5个形态参数差异性均不显著（P＞0.05）;雌雄个体间耳石各形态参数的差异性均不显著（P＞0.05）;在不同叉长组间,耳石各形态参数的差异性均显著（P＜0.05）,而且,采用典型相关分析法分析发现,叉长与耳石各形态参数的相关性均较大,且达到了极显著水平（P＜0.01）;在不同性成熟度间,耳石全长、宽度、背宽和腹噱长在Ⅳ期与Ⅴ期、Ⅴ期与Ⅵ期之间的差异性不显著（P＞0.05）,耳石背长仅在Ⅴ期与Ⅵ期之间差异不显著（P＞0.05）,其它各期之间耳石背长差异性均显著（P＜0.05）,耳石翼叶长在相邻各性成熟期之间的差异性均不显著（P＞0.05）.研究结果表明,性成熟和个体大小与耳石外部形态参数有一定的关系,并影响耳石的生长.

Based on samples taken from Chinese resource exploratory fishing boats in Morocco coastal waters from June to August in 2011,the fishes were measured （mantle length ± 1mm） and weighed （total body weight ± 1 g）,and sex and maturity were identified.The fishes were initially divided into three maturity phases：immature （stage 1,2 and 3）,maturing （stage 4 and 5） and mature （stage 6）.And total length,total width,dorsal length,dorsal width,wing length and ventral length of otolith were measured as morphological variables.The otolith growth impacted by sex maturity and individual size was analyzed by variance analysis.The correlativity between otolith morphological variables and fork length was analyzed by canonical correlation analysis.Results showed that the otolith＇s morphological variables changed with fork length.The differences among maturity stages and fork length groups were examed by varinace analysis （ANOVA） and least-significant difference （LSD） in otolith＇s morphological variables.The difference between the left and right otolith＇s parameters were analyzed.Results indicated that except wing length,it had no difference between left otolith and right otolith in another five otolith＇s morphological variables（P ＞ 0.05）.The difference between sexes in otolith＇s morphological variables was analyzed by t-test.Results showed that there was no difference between sexes in otolith＇ s morphological variables （P ＞ 0.05）,but there were differences between fork length groups in otolith＇s morphological variables（P ＜0.05）.Meanwhile,we found that it was significantly correlative between fork length and otolith＇s morphological variables by canonical correlation analysis（P ＜ 0.01）.Therefore,we could deduce that to some extent,the fork length may be deduced by use of otolith＇s morphological variables.The method could promote further study on the growth of sardines.Among different sex maturity stages,the otolith＇s total length,total width,dorsal width and ventral length had no differences between stage 4 and 5,stage 5 and 6 （P ＞ 0.05）.There was no difference between stage 4 and 5 in otolith＇s dorsal length.The otolith＇ s wing length had no differences among different sex maturity stages.We could find that otolith grow rapidly in immature stage,but grow slowly in maturing and mature stages.Results indicated that it had certain relations between sex maturity,body size and otolith＇s morphological variables,and they may influence otolith shape.