| Zhongjieshan Waters is one of the most important spawning grounds which is lie to the east of Zhoushan Islands. It is composed by 45 islands, including 4 inhabited islands, such as Huangxing, Miaozihu, Qingbang, Dongfushan; and 41 unmanned islands. The area of Zhongjieshan Waters is 202.9 Km2, including 10.48 Km2 area of island.Sepiella maindroni de Rochebrune is commonly called as inkfish or cuttlefish, which widely distributed in China coasted waters and had a high economic value. The cuttlefish has been one of the four famous seafood, and exhausted gradually from the middle 1980s. Recovering the resourses of the cuttlsefish has been the most important task at present.According to the biological characteristics of the cuttlefish, Zhongjieshan Waters was chosen as the object area to study the releasing and enhancement, the rehabilitation of spawning grounds and the effectiveness evaluation of releasing, including three key technologies such as the oosperms hatcher, adhesion substrates and tagged releasing. At last, cuttlefish releasing and effects investigation have been carried out in Zhongjieshan Waters between 2007 to 2009.1. The cuttlefish oosperms could be lied into the seawaters for hatching directly by a netting cage hatcher in order to enhance the resource of cuttlefish. In order to ensure the adhesion and hatching rate of the netting cage hatcher covered with pleny of oosperms, three different hanging culture structures, including pendent structure, cross-hanging structure and bottom-laying structure, were designed based on the hydrodynamic data of single traditional squid cage hatcher. The results showed that the cross-hanging structure has the best effect and then the pendent structure after experiment and comparative analysis.2. The adhesion substrates in the natural waters were mainly including coral, kelp, derelict and so on. The biomasses of coral Plexaauraa in Zhongjieshan Waters are between 0.15-0.64 ind/m2 in average of 0.32 ind/m2, which are also not enough for the rehabilitation of the cuttlefish resources though there are increasing biomass. Therefore, artificial adhesion substrates should be researched. According to the results of adhesion effects of the indoor experiment, and the preferable conditions are as follows: polyethylene (PE) > polypropylene (PP) > wood in material; black > blue > red > yellow in color; cylinder > triangular prism > rectangular prism in shape; and diameter of 0.25-0.50cm. Suitable spacing will be necessary between substrates.3. In the study of tagged releasing, the alizarin complexone solution was injected into the body through the skin of back of the larval cuttlefish in order to dye the cuttlebone directly. The results showed that there are no significant differences between the tagged group and the control group (p>0.05) in growth and death rate respectively. Injectable fluorescent tags could be a suitable marking method for Sepiella maindroni. Due to the lower cost, maneuverability and cognizability of this method, lots of simples could be tagged easily at a time, and make a 100% retention rate when recapture.13.4841 million cuttlefish oosperms in all were released into Zhongjieshan Waters, including 1.2210 million of 2007, 7.3252 million of 2008, 4.9369 million of 2009. The investigation results in 2008 and 2009 showed that plenty of larval and parent cuttlefishes and oosperms were found in Zhongjieshan Waters and nearby sea areas, which indicated that the recovery evidence have been come forth, and it is feasible to rehabilitation the cuttlefish resources by releasing.Sepiella maindroni is the regionally species of the East China Sea, which growing fast and have short reproductive cycle. Meantime Sepiella maindroni is the best releasing species because of the advantages that the oosperms could be released directly by taking low cost. The results of the releasing experiments between 2007 to 2009 showed that it is possible to recover the cuttlefish resources by releasing, and should be continue on a large scale in the future. Meantime, the entironment rehabilitation of spawning grounds, especially the adhesion substrates rehabilitating, should be promoted, and more attention should be given to the protection and sustainable utilization of the cuttlefish resources.
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