Acoustic Marking and Tracking of Brood Crabs of Eriocheir sinensis in the Yangtze River Estuary

Abstract

Acoustic marker tracking method for parent crabs of Chinese mitten crabs in the Yangtze Estuary, characterized by immobilization of acoustic markers on the dorsal shell of parent crabs; no significant difference between marked crabs for evaluation tests and control crabs, indicating that marker crabs can be used for release studies ;Choose the area that overlaps with the migration site of the natural group of crabs on the same day as the mark crab release waters, record the longitude and latitude data of the release point with a GPS instrument, and record the release time; At a depth of 2 meters into the water, the signal strength and time of each acoustic marker are recorded on the monitor; according to the regression equation of the acoustic marker signal strength and distance, the received signal strength is converted into the position of the marker crab, and its GPS data is recorded; The migration speed formula and GPS data are used to calculate the migration speed of each marked crab, and the migratory route is obtained by connecting the activities of the parent crabs; when the sign crabs arrive at the spawning ground, they will stay still and lay eggs for reproduction, and this water area is the spawning ground of the parent crabs.

Description

technical field [0001] The invention belongs to fishery resource monitoring technology, in particular to an acoustic mark tracking method for Chinese mitten crab parent crabs. Background technique [0002] Chinese mitten crab, also known as river crab and hairy crab. In recent years, with the changes in the habitat of aquatic organisms in the Yangtze River, the increase of hydraulic construction and the increase of fishing intensity, the quantity and distribution of Chinese mitten crab resources have also undergone tremendous changes. Chinese mitten crabs are widely distributed in the middle and lower reaches of the Yangtze River. There are mature Chinese mitten crab parent crabs (abbreviated parent crabs) from the Yangtze River estuary area to Shashi, Hubei and other river sections. Every year, when young crabs are fattened in rivers, rivers, lakes, reservoirs and other inland freshwater waters, their gonads gradually mature, and they begin to move in groups to the estuary...

AI Technical Summary

Problems solved by technology

During the migration of parent crabs in the Yangtze River, it is of great significance to accurately grasp the migration rules of parent crabs for both production fishing and scientific research. Therefore, it is urgent to invent a quantitative measurement method for measuring the migration speed, migration route and spawning ground range of the parent crabs in the Yangtze River Estuary, so as to accurately grasp the characteristic values ​​of the parent crab migration rules, so as to provide support for the fishing and habitat protection of the parent crabs in the Yangtze River Estuary. , multiplication and release, ecological restoration, etc. provide a theoretical basis

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