曼氏无针乌贼(Sepiella maindroni)繁殖习性及其产卵场修复的研究

REPRODUCTIVE AND SPAWNING HABITS OF SEPIELLA MAINDRONI OFF ZHEJIANG,CHINA

采用对比分析方法,观察了曼氏无针乌贼的繁殖习性,比较了不同产卵附着物的附卵效果,选择典型产卵场(中街山列岛海区)进行附着物的调查。结果表明,曼氏无针乌贼有较高等复杂的性行为,有显著的求偶、争偶及雌雄搏斗现象,乌贼交配对其它乌贼交配有诱导作用;乌贼对附卵基有严格选择,没有充足适宜的附卵基,不仅使乌贼产卵时间延迟、数量减少,而且易被水流冲散、沉入底部致受精卵大量死亡,是影响乌贼繁衍的重要因素;附卵基附卵效果依次为聚乙烯(PE)绳、聚丙烯(PP)绳、钢筋、竹子、木头,颜色依次为黑色、蓝色、红色、黄色,形状依次为圆柱体、正三棱柱体、正长方体、扁长方体,粗度以直径0.25—0.50cm为宜,此外附卵基间应有适当空隙;目前,中街山列岛海区柳珊瑚(Plexaauraa sp.)生物量为0.15—0.64棵/m2,平均生物量为0.32棵/m2,资源数量趋于恢复,但远不能适应乌贼资源修复需要。增殖放流试验表明,修复乌贼资源的可能性很大,但在加大增殖放流工作的同时,必须尽快开展产卵场生态环境修复尤其是产卵附着物修复工作。

Reproductive and spawning habits of Sepiella maindroni de Rochebrune were studied for understanding the animal＇s reproduction in Zhongjieshan Waters off Zhejiang, China, one of the spawning grounds. Factors affecting the oosperms adhesion on different substrates were examined, including material type, color, size, and shape. The sexual behavior of the animal from displaying, fighting, mating, spawning, were observed complicated. Study shows that S. maindroni are very picky for the substrates. Unfavarable substrates would not only affect the egg laying amount, but also the survival rate of oosperms. The preferable conditions are as follows： polyethylene （PE） 〉 polypropylene （PP） 〉 steel 〉 bamboo 〉 wood in material; black 〉 blue 〉 red 〉 yellow in color; cylinder 〉 triangular prism 〉 rectangular prism 〉 wafery rectangular prism in shape; and diameter of 0.25--0.50cm. At present, the biomasses of coral Plexaauraa sp. are between 0.15-- 0.64 ind/m^2 in average of 0.32 ind/m^2, showing a trend of enhancement; however, it is still far more satisfactory for the cuttlefish resource recovery. Practice of releasing and enhancement has been proven very feasible to restore the cuttlefish natural habitat. Meanwhile, repairing the spawning grounds by providing favorable adhesion substrates is suggested in the future.