Ecological studies on barnacle Balanus rostratus as a new species for aquaculture

1.在日本北方陆津湾5、10、20、30和40 m的水深中，10 m处沉降最多。在10和20米深度的藤壶生长大于5米的15个月。新定居（1993年）和一岁（1992年）类藤壶被移植，并保持了两年多的冲来湾，日本东北部。2年后，前者基径增长32 mm，后者基径增长42 mm。这意味着它需要3或4年的时间来增长42毫米大小的Okirai湾。水温对藤壶生长的影响在10、15、20和25 ℃的水温条件下，温度越低，新附着的藤壶生长越大，存活200天的时间越长。一年级藤壶表现出相同的温度反应的0年级。藤壶在20 ℃的制度表现出逐渐下降的生存。结果表明，温度低于15摄氏度是该物种维持其种群的理想条件.幼虫分布2月中旬已出现无节幼体，3月仅发现少量无节幼体。塞浦路斯人倾向于出现在Mutsu湾的东半部，而不是西半部。硅藻Asterionella japonica和海链藻Thalassiosira nordenskioeldii在10- 1 - 2 ℃、1-2条/ml、不受光照影响的条件下生长良好。需要搅拌以通过充气或推进来分散幼虫。在300 cells/无节幼体/h（Ⅱ期）~ 1700 cells/无节幼体/h（Ⅵ期）的范围内，对日本对虾的摄食率随着幼虫的生长而增加.在7种人工基质中，藤壶分别固定在聚氯乙烯（PVC）和橡胶板上。一个用过的轮胎将是一个很好的基础，不仅为解决，但也消除藤壶。

1. Settlement depth and growth in the seaSettlement was most frequent at the depth of 10m among 5,10,20,30, and 40m in the Mutsu Bay, northern Japan. Barnacles at 10 and 20m in depth grew bigger than the ones at 5m for 15months. Newly settled (1993) and one-year old (1992) classes of barnacles were transplanted and kept for more than two years in Okirai Bay, north-eastern Japan. They grew 32mm in basal diameter for the former and 42mm for the latter after 2 years. This means it takes 3 or 4 years to grow 42mm in size in Okirai Bay.2. Effect of water temperature on the barnacle growthThe lower the temperature, the bigger newly attached barnacles grew and the more they survived for 200 days among 10,15,20, and 25ﾟC temperature regimes. One-year class barnacles showed the same response to the temperature as those of the 0-year class. Barnacles in 20ﾟC regimes showed gradual decrease in survival. The results show that a temperature lower than 15ﾟC is desirable for this species to sustain their population.3. Distribution of larvaeCyprid larvae had already appeared in mid February, and only a fewnaupliar larvae were found in March. Cyprids tended to appear more in the Eastern half of the Mutsu Bay rather than in the Western half of it.4. Larval rearing and their grazing ratesDiatoms Asterionella japonica and Thalassiosira nordenskioeldii supported good growth of larvae under 10-12ﾟC,1-2 larvae/ml, and irrespective of light. Stirring was needed to scatter the larvae by aeration or by propulsion. Grazing rate to A.japonica was increased with growing the larva from 300 cells/nauplius/h (stage II) to 1700 (stage VI).5. Artificial substrate for settlingBarnacles were settled on poly vinylchloride (PVC) and rubber plates among seven different artificial substrata tested. A used tire would be a good substratum not only for settlement but also removing barnacles from it.