A method for trawling Chinese mitten crab parent crabs in the Yangtze River Estuary

Abstract

The invention relates to a method for catching eriocheir sinensis parent crabs, in particular to a method for catching eriocheir sinensis parent crabs in a trawling mode at the Yangtze estuary. According to the method, a fish boat, a front horizontal rod, a rear horizontal rod, three bottom trawls and three net bamboo pieces are adopted. The method is characterized in that the front horizontal rod is horizontally arranged at the nose of the fish boat, the three net bamboo pieces are fastened to the front face of the front horizontal rod through a trawl rope, the net bamboo pieces are rectangular, 2.5-3.0 m long and 1.5-2.0 m wide, two floaters are tied to the upper side of each net bamboo piece, two sinkers are tied to the lower side of each net bamboo piece, and the net bamboo pieces tied to the front face of the front horizontal rod vertically float in water under the pushing of water flow; the rear horizontal rod is horizontally arranged at the stern of the fish boat, and the three bottom trawls are tied to the stern of the rear horizontal rod and used for catching the eriocheir sinensis parent crabs; the three net bamboo pieces pull the fish boat and the trawls to catch the parent crabs under the pushing effect of water flow, and a tail vane of the fish boat controls the forwarding direction.

Description

technical field [0001] The invention belongs to a method for catching brood crabs of mitten crab sinensis. Background technique [0002] The Chinese mitten crabs in the Yangtze River Basin generally grow to 2 years old in rivers and lakes, and their gonads begin to develop rapidly in late September. By mid-to-late October, most of the parental crabs' gonads have developed into the fourth stage, and they leave the rivers and lakes for reproductive migration to the Yangtze River Estuary. At the end of November, parent crabs gather in the brackish waters at the junction of the Yangtze River Estuary and the shallow sea to start breeding. The female parent crabs will attach fertilized eggs to the bristles of their ventral limbs and gather in waters with higher salinity. It's basically over. At present, the main tools for fishing mitten crabs during the winter flood season in the lower reaches of the Yangtze River include ground cages, nets, and trawls. The use of these fishing ...

AI Technical Summary

Problems solved by technology

At present, the main tools for fishing mitten crabs during the winter flood season in the lower reaches of the Yangtze River include ground cages, nets, and trawls. The use of these fishing tools often requires a lot of human and financial resources, especially for trawling. Running the diesel engine on board for a long time will lead to higher fuel costs and lower fishing benefits

In addition to diesel and other chemical raw materials as the conventional source of power for fishing boats, in recent years people have gradually adopted solar energy, wind energy, etc. to provide power sources for fishing boats in order to reduce fuel costs, but most of these devices are expensive and the size of the devices required to drive fishing boats is large , so it is difficult to apply to small fishing boats

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