长江口凤鲚生物学特征及其资源利用研究进展

为探究长江口凤鲚(Coilia mystus)资源的保护利用和科学管理,通过对已有资料收集整理和分析,综述了长江口凤鲚的形态特征、分布、洄游、年龄与生长、摄食习性和繁殖发育等基础生物学研究进展,并论述了近50余年来长江口凤鲚资源的开发利用状况与管理现状。凤鲚的自然分布较广,不同凤鲚群体的分化明显,洄游履历类型多样。长江口凤鲚的年龄组成以1~2龄占优,属于匀速生长类型,繁殖群体的组成呈现低龄化和小型化的趋势。长江口凤鲚在1+龄即可达到性成熟,成熟个体一年可繁殖一次,产卵属于单峰一次性产卵类型。长江口凤鲚的生殖力整体上呈现出下降趋势,其绝对怀卵量和相对怀卵量除个别年份外均呈现下降趋势。长江口凤鲚产量自1974年达到历史顶峰后,除1995年出现大幅反弹外,总体呈现波动下降趋势。近几年长江口凤鲚汛期资源量为40 t左右,已基本不能形成渔汛,其资源岌岌可危。据此,建议加强长江口凤鲚种群动态、生境需求和人工繁育等方面的研究,为长江口凤鲚资源的可持续利用和发展提供科技支撑和基础资料。

Biological characteristics and resource utilization of Coilia mystus in the Yangtze Estuary

In order to explore the protection,utilization and scientific management of Coilia mystus resources in the Yangtze Estuary(YE),the biological characteristics including morphology,distribution,migration,age and growth,feeding habits and reproductive development of C.mystus,and its resource utilization and management in the YE were reviewed based on research papers in the past 50 years.C.mystus distributed widely along the Chinese coasts,with obvious differentiation among different geographic populations.Habitat history of C.mystus was diverse.The dominant YE population of C.mystus was composed by 1 to 2 years old individuals,which belonged to the type of uniform growth,and tended to be smaller and younger.The YE population of C.mystus reached maturity at the age of 1 and reproduced once a year.Its spawning was a single peak type of one-off spawning.The fecundity,including absolute and relative fecundity,of C.mystus in the YE showed a declining trend on the whole except a few years.After reaching a historical peak in 1974,the yield of C.mystus in the YE showed a trend of fluctuation and decline except for a sharp rebound in 1995.In recent years,the annual resource of C.mystus in fishing season has been estimated to be about 40 tons,which has declined sharply than before and has lost commercial fishing value.Therefore,future suggestions of studies on the population dynamics,habitat requirement and artificial breeding of C.mystus in the YE were put forward,which should provide scientific and technological support and basic data for the management and sustainable utilization of C.mystus resources in the YE.