Stock status and conservation dilemma of species of Acipenseriformes in the Yangtze River and relevant suggestions

This paper summarized the changes in the natural resources of three sturgeon species (Psephurus gladius, Acipenser sinensis, and Acipenser dabryanus) over the past 40 years, quantified the artificial stocking populations of A. dabryanus and A. sinensis, and then assessed the effectiveness of restocking. The influence factors that cause the ineffective releases widely depend on species characteristics and distribution. Overfishing of ten resulted in the fact that the artificial released A. dabryanus individuals were inevitably captured within 6 months as bycatch after they were released. The insufficient number of released A. sinensis combined with overfishing in the Yangtze River and offshore caused the inefficient contribution to the wild population of A. sinensis. We believe that the past releasing input intensity of both A. dabryanus and A. sinensis cannot reach the sufficient replenishment level of the natural breeding population. We discussed the misconceptions and shortcomings in the action, management, and policy-making of P. gladius, A. sinensis, and A. dabryanus conservation over the past 40 years. In the current ecological protection era , We should promote the implementation of 3 key protection measures urgently: 1) to prepare and implement the priority project of A. dabryanus rescue action plan; 2) to propose more operational priority projects for in situ conservation, ex situ conservation and genetic diversity conservation based on A. sinensis rescue action plan; 3) to establish a species rescue action plan project of A. sinensis and A. dabryanus, and to optimize and integrate the existing ecological compensation programs involving their habitats or protected areas. We believe that we can restore the natural populations of A. dabryanus and A. sinensis, by restoring their natural reproduction. Then we can realize the harmonious coexistence between human and nature, and promote the sustainable development of social economy in the Yangtze River basin.