CURRENT SITUATION OF RESOURCES AND (Lutraria rhynchaena) IN VAN DONG DISTRICT, QUANG NINH PROVINCE

Abstract

This study aims to assess the resources and the current status of the art of shrimp farming in Van Don, Quang Ninh province today through investigation and survey. The data in the article are collected through methods of quick survey, investigation and interviews with people. The results obtained at Van Don mainly distributed the comedones Lutraria rhychaena (Jonas 1844) with density ranging from 0,1-0,2 species/m2, species Lutraria arcuata (Deshayes in Reeve, 1854) only appears in Dong Xa with very little density. The area of distribution of ​​these two species has been pushed offshore, the aquatic resources are seriously reduced and the cultivated area is being replaced by a number of other mollusks. Through a survey of 400/1250 households with aquaculture jobs in 8 towns and townships in Van Don district, 152 households still maintain the profession of cultivating comedy, the farming households are scattered in the district with very small area out of a total of 2,100 ha of mollusk farming. The stocking density is from 25-50 commercial/cage, the seeding season is from April to September every year. Culture time is from 10-12 months/crop, harvested size from 20-40g/head (25-50 g/kg), harvested output is 23,4 tons/ha, revenue is 2,34 billion VND. bring profits to farmers about 0,669 billion VND. The study has provided information about the resources and distribution area of Lutrariar rhynchaena in Van Don, at the same time assessed the current status and profitability of shrimp farming and proposed some solutions for the development of monoculture in Van Don.