大閘蟹養殖

The Culture of Chinese Mitten Crab

大閘蟹為新興的養殖水產物種，近三年台灣每年由大陸與香港地區進口蟹苗近25噸以上。然而，台灣養殖大閘蟹業者大多數養殖經驗及技術尚未完全成熟，對於大閘蟹基本生長條件與環境需求仍在摸索階段。常因放養密度過高、投餵過量、底質老化、水色不穩定及防逃設施不完善等問題，導致育成率不高；養殖過程中因池塘日常管理不當，容易爆發疾病而發生大量死亡，導致生產量降低；在飼料營養調配上，則因尚未掌握大閘蟹的最佳成長飼料配方，而造成成熟度不佳，導致個體小、生殖巢發育不夠飽滿等問題。在市場銷售上，大閘蟹市場通路明顯較魚蝦、貝類市場小，所以規劃與整合完善的產銷通路，提升產品價值，以增加養殖戶受益更是急須解決的問題。在生態保育上，應加強養殖期間的大閘蟹防逃措施，避免破壞台灣原有的自然環境與生態。本文針對大閘蟹生態習性、放養準備與養殖管理、常見病害以及養殖成本方面進行完整介紹，並對大閘蟹養殖提出相關建議；此外，政府相關單位應積極輔導台灣養殖大閘蟹業者，宣導正確的養殖管理觀念及進行養殖技術交流，才不致造成社會資源浪費；同時，對於優良養殖業者應進行產品認證以建立品牌，促進消費者的購買慾望與食用安全。 Chinese mitten crab (Eriocheir sinensis) is an emerging cultured aquatic species in Taiwan. In latest three years, the total amount of the crab larvae imported into Taiwan from mainland China was estimated to be higher than 25 metric tons per year. However, most of the farmers lacked practical experiences and techniques in culture of the crab including basic knowledge of optimal growth condition and environmental requirement. High culture density, over-feeding, aged pond sediment, instability of water color and insufficient facilities to avoid escaping often caused low survival rate of the crab. Inappropriate aquacultural management might also cause the out breaks of diseases leading to the reduction of total yield. The suitable formulation of commercial feed for the crab has not been established leading to the occurrence of incomplete maturation, small size and less-developed gonad etc, after culturing. For marketing, the logistic channel for the crab was apparently smaller than that of fish and shellfish in Taiwan. Therefore, an appropriate planning for the marketing to promote the price of the cultured crab is in need urgently. This paper described the ecology, behavior, aquacultural preparation and management, common diseases and cost analysis of culturing the crab. In addition, suggestions were given concerning the crab culture. Advice and help to the crab farmers to avoid loss from governmental authority are very important especially the education and training of good practice and exchange of culture experiences. Furthermore, the establishment of accreditation system for brand mark to promote consumption and safety of this high valve-added crab product.