Evaluation of survival and metamorphosis of larvae of Caligus rogercresseyi (Boxshall and Bravo, 2000) (Crustacea, Copepoda) in Chile, depending on temperature, salinity and oxygen

Abstract The present study assessed the percentage of survival and metamorphosis of larval stages of Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplius I, nauplius II to and nauplius II to copepodite, conducting bioassays in triplicate with 50 larvae each, nauplius I or nauplius II, at temperature of 12 °C, 15 °C and 18 °C; salinity 20, 23, 25, 2729, 31, 33 and 35 g/L and oxygen saturation with ranges between 30-60%, 90-100% and 190 - 200%. Bioassays were performed in station Quillaipe of Fundación Chile, Puerto Montt, Chile. It is concluded that the temperature is inversely proportional to the time of metamorphosis and survival of the larvae of Caligus rogercresseyi . In salinity is observed that increased this, greater is the percentage of survival and metamorphosis is faster, while the larvae do not survive less than 20g/L. Oxygen saturation ranges indicate that the larvae do not survive at saturations between 30-60%, and it had no differences between 90-100% saturation and 190-200%.

摘要 本研究评估了罗杰氏鱼虱（Caligus rogercresseyi, Boxshall and Bravo, 2000）第一无节幼体、第二无节幼体至桡足幼体阶段的存活率与变态率。实验设置三次重复，每组包含50尾第一无节幼体或第二无节幼体，分别在12℃、15℃、18℃，盐度20、23、25、27、29、31、33、35 g/L，以及氧饱和度为30%~60%、90%~100%、190%~200%的条件下开展生物测定。实验于智利蒙特港的智利基金会基莱佩（Quillaipe）站进行。研究结果表明：温度与罗杰氏鱼虱幼体的变态时长及存活率呈负相关；盐度方面，随盐度升高，幼体存活率提升且变态速度加快，且幼体无法在盐度低于20 g/L的环境中存活；氧饱和度实验结果显示，幼体无法在30%~60%的饱和度条件下存活，而90%~100%与190%~200%饱和度组间无显著差异。