"A trend of the otter trawl net fishery in Ise Bay [Japan], 1."
1986
"Nakajima, H. (Mie-ken. Government Office, Tsu (Japan))."
"The small trawl net fishery is one of the most imoprtant fisheries in Ise Bay. It catches many kinds of fishes, prawns, crabs, shells, and so on. Recently, yearly fluctuations of catches except for shells tend to decrease gradually in spite of beocming larger in size of ship and modern equipments. Therefore, the author tried to obtain a trend of the otter trawl net fishery which mainly cathes fishes, prawns, crabs, etc., using the data on the fishery over the period of 1970 to 1983. Annual CPUE of the fishery in each year kept about 50 kg/boat-day from 1970 to 1973, and it increased about 70 kg/boat-day from 1974 to 1977, then it has gradually decreased as a whole since 1978. A relationship between fishing effort and CPUE has been negatively correlated since 1975. A relationship between catch and fishing effort described sigmoid curve and has showed a stable level since 1981. These results indicate that an increase in fishing effort abve the present level maybe reduce to the reduction of the stock and over-fishing in the fishery."
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