西藏鮡科鱼类的繁殖生物学研究

The fishes of Tibet Plateau are precious living resources, especially sisorid catfishes. Recent years, because of human's activity, e.g. overfishing, the resources of sisorid catfishes have decreased dramatically. It is urgent that making a scientific protection measurement to protect, recover and utilize resources reasonably. When is the best spawning period (e.g.age and season), and how is the best ecological condition of breeding? Their spawing type, fecundity and so on also need further investigation. This project will obtain spawning period, spawning pattern, fecundity, condition of spawning ground, and age and length of first maturity to analyze the tactics of three fishes. Their reproductive biology can provide references to protection, utilization, and artificial breeding of sisorid catfishes.

高原鱼类，特别高原鮡科鱼类是我国宝贵的鱼类资源。由于其较高的食用和经济价值，近年来遭到人们的大肆酷渔滥捕，造成鮡科鱼类资源的急剧下降，有的几近灭绝。因此开展高原鮡科鱼类的资源保护与人工繁育恢复工作已迫在眉睫。然而其最佳繁殖时期（年龄、季节）、最适宜产卵的生态条件如何？以及它们的产卵类型、繁殖力等都有待进一步研究。本项目拟通过研究三种鮡科鱼类（黑斑原鮡、黄斑褶鮡和扁头鮡）的繁殖期、产卵类型、繁殖力、初次性成熟的年龄和体长、产卵场状况等繁殖策略，旨在阐明鮡科鱼类对高寒环境的适应特性和繁殖生物学特征，为进一步开展鮡科鱼类的资源保护、合理利用和人工繁育提供科学依据。

近年来由于过度捕捞等活动，导致西藏鮡科鱼类资源急剧下降。开展高原鮡科鱼类的资源保护与人工繁育恢复工作已迫在眉睫。然而缺乏比较详细的鮡科鱼类生物学资料。本研究主要开展了扁头鮡和黑斑原鮡的年龄生长及繁殖生物学特征等工作，主要得到如下结果：.（1）耳石是鮡科鱼类最佳的年龄鉴定材料，脊椎骨次之。.（2）雌性扁头鮡初次性成熟年龄为10.5龄，雄性为8.4龄；雌性黑斑原鮡初次性成熟年龄为6.6龄，雄性为8.4龄。.（3）扁头鮡的繁殖期处于5-8月，为分批产卵类型；黑斑原鮡不分批产卵，繁殖时间集中在5-6 月。.（4）扁头鮡的绝对繁殖力为145.3 ± 63.253粒，比黑斑原鮡的绝对繁殖力721±356.2 粒小。. 这些资料为进一步开展鮡科鱼类的资源保护与人工繁育提供科学依据。