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The survey in the, Huanghe River estuary indicated that the 85 fish species found there comprised three faunal elements: warm-water species (29.4%), warm-temperate species (55.3%) and cpld-temperate species. (15.3%). The seasonal changes of fish species, density and bipmass are obvious. The total biomass is highest (7699t) in August and lowest(489 t) in January. Setipinna taty has mean density of 9278 indiv/km2, and is the most important species constituting 25.5% of the total weight of fish caught. Trichiurus haumela was a dominant species in the 1950s, but no one was caught in this survey. There were obvious changes of the dominant fish species during the recent three decades. The demersal fish biomass has dropped greatly to only 1/10 in over 50 years since 1930.
The survey in the, Huanghe River estuary indicated that the 85 three species of marine species found warm water species (29.4%), warm-temperate species (55.3%) and cpld-temperate species. (15.3%). The seasonal changes of fish species, density and bipmass are obvious. The total biomass is the highest (7699t) in August and lowest (489 t) in January. Setipinna taty has a mean density of 9278 indiv / km2, and is the most important species 25.25 % of the total weight of fish caught. Trichiurus haumela was a dominant species in the 1950s, but no one was caught in this survey. There were obvious changes of the dominant fish species during the recent three decades. to only 1/10 in over 50 years since 1930.