Status and conservation of sturgeons in Amur River, China: A review based on surveys since the year 2000

Abstract

Heilongjiang ( Amur) River Sturgeon ( Acipenser schrenckii) and Kaluga (Huso dauricus) are the only two species of Acipenseri-formes indigenous to the Heilongjiang ( Amur) River basin. As commercially important fishes for caviar production, these two species are confronted with over-fishing and population depletion. In 1987, the volume of exported caviar reached a peak of 26 metric tonnes (mt). Since 1992, the caviar production has declined gradually, fluctuating between 6.46 mt and 12.7 mt, with an annual average production of 9.16 mt. Thus, in China the export quota decreased to 5.94 mt after 2001. Only 6 companies were licensed by China to export caviar from these species. For the restocking of these two species, hatchery controlled reproduction ( including incubation of eggs and release of fry) continued from 1988 to 2005. During this period a total of 845 million fry have been released into the Heilongjiang River. The measures proposed to restore the natural resources include strict observation of local regulations on fishing and enforcement of fishing-prohibition periods. Capture quotas should be set for these two species and strictly enforced according to their existing resources. Sturgeon-breeding farms should be established to propagate and raise sturgeon fry to larger size, with the aim of releasing the fingerlings into the rivers and reservoirs so as to maintain and eventually enhance this natural resource.