Artificial Propagation and Larval Rearing of the Clown anemonefish（Amphiprion ocellaris）

• Main Authors: HO, YUAN-HSING, 何源興
• Other Authors: PENG, REN-JUN
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/umpey9

碩士 === 國立臺東大學 === 生命科學研究所 === 95 === The purpose of this study is aimed to understand the reproductive behavior, larval culture under artificial environment of clown anemonefish ( Amphiprion ocellaris)and other relevant materials. Besides, we hope the result of the study can reduce the trade of wild fish in the ornamental fish market in the future. The result showed that the minimum organism size was about 4.4 mm in total length, mean length was about 5.63 ± 0.66 cm for males（Mean ± S.D.；4.4 - 6.4 cm）and the minimum organism size was about 5.8 mm in total length, mean length was about 6.97 ± 0.78 cm for females. Females were significantly larger than males in sea anemone's clown fish school. Ovulation occurred all year round under the following conditions: temperature at 22 - 30℃, salinity of 34 - 35 psu and the intensity of illumination above water is 6,000 - 20,000 LUX. The highest record was 29 ovulations in one year. The spawning interval was 9 - 20 days, and the fertilized eggs hatched in 6 - 11 days. These adhesive demersal eggs are yellow to orange and ellipsoidal, and were about 2.32 ± 0.10 mm in length and 0.95 ± 0.07 mm in width. The yolks were about 1.44 ± 0.12 mm in diameter and the newly hatched larvae were about 4.35 ± 0.14 mm. Parental care behaviors for the ovum occurred after spawning. The behavior occurred 7 ± 5.7 times / 30 minutes and 40 ± 6.6 times / 30 minutes for females and males, respectively, from spawning to hatching. It indicates that parental behavior is mainly carried out by males. The diameter of fertilizes eggs and the length of larvae for 2+, 3+ and 4+ fish were significantly different. The eggs and larvae of 2+ fish were significantly larger. This may resulted from the beginning of spawning behavior for younger fish in their life history and they had better nutrition and stamina. According to the results, the time interval for the embryo to hatch is in inverse ratio to water temperature. The hatching period was 6 and 8 days under 29℃ and 23℃ water temperature, respectively. At day 11th after hatching, the larvae turned reddish orange in color and symbiosis with sea anemones occurred at this time. The biological feedings for anemonefish at initial larvae stage was rotifer and copepod. The density of feedings thrown can't be lower than 5000 Rotifer / liter and 250 copepods / liter for each fish. Microalgae was added to stabilize water quality and to nourish rotifers. The supply of feedings should be applied at the same time. At day 35 after hatching, pellet diet can be applied to the fries. At about day 160, average size of juveniles was 38.25 ± 2.95 mm and the pattern of band and color of juveniles were the same with adults.