Shallow caged crabs adopt the long-line method, which not only avoids the characteristics of easy self-mutilation of the crab, but also applies to sea areas with large waves, and expands the shallow sea breeding space. In recent years, Yuhuan County of Zhejiang Province has emerged vigorously and its benefits are not rising. bandit. This article summarizes Yuhuan County's recent farming experience and exchanges with colleagues. First, the basic structure of aquaculture facilities The basic structure of long-line cages is to use a polyethylene rope with a length of 10Om and a diameter of 1.4cm-2.Ocm as a large file, with plastic floats or foam floats as floats in the middle, and each floating buoyancy. Above 15-20kg, each float spacing is 4m. At present, the crab cage used for breeding is a plastic cage consisting of four to five layers of circular chassis. The height of the cage is about O.8m, the diameter is 3Ocm, and the height is 15cm. There are more than 50 holes with a diameter of 0.3cm at the bottom of each plate. To exchange seawater, a 7cmx7cm door is caged on each floor. One end is fixed with steel wire and the other end is pushed open for feeding. If the crab is fattened, the door is fastened with a soft plastic wire with a diameter of 0.3 cm and a length of 5-6 cm, and a small 2.5 cm X 2.5 cm door is provided in the middle of the door for feeding. The cage is fixed on the big rake with an O.6-1cm thick polyethylene rope. The distance between the plastic cages is 1m/meter, and both ends of the gong are fixed with bamboo and bamboo. Second, the choice of sea area According to the characteristics of the longevity type of caged crab, the sea area should choose moderate flow, wind and waves, island barriers, water quality, turbidity, water pH value of 7.8-8.4, dissolved oxygen above 4mg / L, chemical consumption Oxygen and biological oxygen consumption must not exceed 54mg/L, and there is no industrial pollution and other harmful elements in the sea area. Third, the crab species of stocking crabs have green shell, yellow shell, flower shell, purple shell four to the best quality of green crab. The stocked crab species require hard shells, strong living ability, and completeness. Normally, 100-300/kg crab species will be stocked in May of the first half of the year and two will be placed on each layer. The water temperature during stocking will generally be around 20°C. If the crabs are used for fattening, then the crabs are usually stocked at O.15kg-O.25kg/body after the crabs are mated each October. Fourth, develop management The bait and feeding of the crab are omnivorous. In addition to eating shellfish, fish and shrimps, but also eat seaweed sprouts, other animal bodies and feces, shrimp with bait, etc., basically animal-based feed. The caged crabs are mainly fed with low-value fish and shrimps. The amount of bait is generally controlled between 7% and 10% of the body weight of the crab, but the actual feeding needs to be based on the crab's feeding range and feeding rate. In contrast, young crabs feed more than big crabs. The amount of feeding is also related to the water temperature. When the water temperature is 20-27°C, the appetite is strong, and the growth is rapid. It should be used for feeding more food. When the water temperature drops below 15°C, less investment can be made. Normally, the water temperature is 2O°C-27°C and it is fed once a day. Usually 1-3 small trash fishes are used once. Normally, timing and quality should be achieved. When the water temperature drops below 15°C, the feed can be thrown every 2-3 days due to a decrease in food intake. 2. Culture cage cleaning Because the culture cage is hung in the sea area, it is easy to attach various organisms and mud. Normally, when the temperature is high, it should be cleaned once every 10 days to 15 days. When the temperature is low, it can be cleaned once every 2 days and 30 days. Everyday, we must also regularly check whether the breeding cage is firm and broken. 3. Biology assays should be performed every two weeks to perform a biological assay that includes the length of the anatomy (the vertical distance from the central puncture of the cephalothorax to the posterior border of the iliac crest) and the width of the nail (a straight line between the thorns on both sides of the cephalothorax) Distance, weight, gastric feeding, vitality, and health status to measure the effects of culture. V. Harvesting Harvested crabs harvest time is at the end of autumn. When the water temperature drops below 15°C, they should be harvested in time. In this way, the crab grows to 16cm and its weight reaches 0 through 5 months to 6 months of breeding. 25kg/only, the survival rate is usually more than 70%. If it is for fattening purposes, it should be sold at high prices around the Spring Festival. After 4 months to 5 months of fattening growth, the standard increase of up to 20cm, weight of 0.4Okg/above, the survival rate of more than 9O%. When the crabs are sold, the crabs can be placed in sea water with a lower temperature to make them slow, and then the crab legs can be tied with a rubber band, or they can be tied directly to the market with rubber bands. VI. Key to Improving the Survival Rate of Breeding 1. In the aquaculture area, it is advisable to choose a river where the water flow is not slow and the seawater is relatively empty. Otherwise, it is very easy to breed mosses or barnacles and attach it to the crab body, causing the death of the crab. 2. Crab cage diameter should not be less than 30cm, the height should not be less than 12cm, because crabs usually have to turn, too small crab cage can easily cause the top of the two crab shells in the cage hole at the bottom, can not turn to death. 3. In the young crab stage, the crab cage should not be thrown back into the sea area after feeding and cleaning, so as to prevent the crab from being shocked and frightened. 4. The salinity of seawater is required to be stable at more than 20%, otherwise it will affect the growth of crab shells. VII. Living transport of crabs The shuttle crabs must be strictly handled during long-distance transportation for export or supply in the Mainland. Choose a healthy crab body with a weight of 200g or more, complete limbs and full body, and raise it in the cement pool for 1 day to 2 days, then drain it to excrete, then remove the weak crab and place it in a plastic fish box, each box. About 12 or so, they were transferred to seawater at 14°C-15°C, cooled to 7°C-8°C with an ice bag, and the shuttle crabs were put into a dormant state and transported to the 8-10°C air temperature in the workshop. Packing sawdust and carton first cool, then sawdust flat on the bottom of the carton thickness 1.5cm, then put the crab flat on the sawdust, and then cover the sawdust 1-2cm, so packing 3-4 layers, and finally sawdust Fill it up. Sealed storage at low temperature. The refrigerated truck is transported at a temperature of 8-10°C for 24h to 48h. After being transported, it is stocked in low-temperature seawater. After it is slowly revived, it is sold for sale.