异齿裂腹鱼（ Lloyd）为中国特有种，由于过度捕捞和生物入侵等因素，其种群生存受到极大威胁。2008年8月至2009年8月在西藏雅鲁藏布江拉孜至尼木江段共采集异齿裂腹鱼1126尾，利用单位补充量模型对其种群资源利用现状及其养护措施进行了研究。结果表明，雌性和雄性异齿裂腹鱼年总瞬时死亡率（）范围分别为0.08/a~0.09/a和0.10/a~0.12/a，雌雄鱼的当前捕捞死亡率（）范围分别为0.02/a~0.03/a和0.04/a~0.06/a。异齿裂腹鱼雌鱼种群繁殖潜力比范围为61.7%~73.1%，全部高于目标参考点（40%），雄鱼种群繁殖潜力比范围为48.5%~63.3%，全部高于目标参考点（40%）。这表明在现有的资源养护措施下，异齿裂腹鱼种群的利用基本合理，但要防止长期持续利用对种群的不利影响。14种不同养护措施模拟结果表明，将异齿裂腹鱼的起捕年龄设置为不小于17龄或禁渔期至少设置为2-5月，可实现对其资源的有效养护。

, an endemic species in China, has been threatened by overfishing, and biological invasion, among other factors. A total of 1126 individuals were collected between August 2008 and August 2009 from Lhaze to Nyemo on the Yarlung Zangbo River, Tibet. The population resources and fishery conversation policies of the fish were studied using per-recruit models. The total instantaneous annual mortality ( was 0.11/a for females and 0.16/afor males. The ranges of natural mortality () for females and males were 0.08/a-0.09/aand 0.10/a-0.12/a, respectively. The range of the current fishing mortality () was 0.02/a-0.03/a for females and 0.04/a-0.06/afor males. The range of the spawning potential ratio of was 61.7%-73.1% for females and 48.5%-63.3% for males, both of which were significantly higher than the target reference point (40%). This indicates that the stock of could be reasonably exploited under the current fishery conversation policy, but special attention should be paid to the stock of in case of over-exploitation in the long-term. To evaluate the protective effects of capture age and seasonal closure, 14 different fishery conversation policies were simulated. The results suggest that the stock of could be effectively conserved by enhancing the capture age to 17 years or above and allocating seasonal closure from at least February to May.

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国家自然科学基金青年科学基金项目（31600367）；中华人民共和国农业农村部财政专项（西藏重点水域渔业资源与环境调查）.