Ocean acidification, a reduction in the pH of the oceans caused by increasing CO₂, can have negative physiological effects on marine species. In this study, we examined how CO₂-driven acidification affected the growth and survival of juvenile golden king crab (Lithodes aequispinus), an important fishery species in Alaska. Juveniles were reared from larvae in surface ambient pH seawater at the Kodiak Laboratory. Newly molted early benthic instar crabs were randomly assigned to one of three pH treatments: (1) surface ambient pH ~ 8.2, (2) likely in situ ambient pH 7.8, and (3) pH 7.5. Thirty crabs were held in individual cells in each treatment for 127 days and checked daily for molting or death. Molts and dead crabs were photographed under a microscope and measured using image analysis to assess growth and morphology. Mortality was primarily associated with molting in all treatments, differed among all treatments, and was highest at pH 7.5 and lowest at ambient pH. Crabs at pH 7.5 were smaller than crabs at ambient pH at the end of the experiment, both in terms of carapace length and wet mass; had a smaller growth increment after molting; had a longer intermolt period. Carapace morphology was not affected by pH treatment. Decreased growth and increased mortality in laboratory experiments suggest that lower pH could affect golden king crab stocks and fisheries. Future work should examine if larval rearing conditions affect the juvenile response to low pH.

海洋酸化，即由 CO ₂增加引起的海洋 pH 值降低，会对海洋物种产生负面的生理影响。在这项研究中，我们研究了 CO ₂驱动的酸化如何影响幼年金王蟹（Lithodes aequispinus)，阿拉斯加重要的渔业物种。幼鱼是在 Kodiak 实验室从表面环境 pH 值海水中的幼虫中培育出来的。新蜕皮的早期底栖幼蟹被随机分配到三种 pH 处理之一：(1) 表面环境 pH ~ 8.2，(2) 可能原位环境 pH 7.8，和 (3) pH 7.5。30 只螃蟹在每个处理中被关在单独的细胞中 127 天，每天检查蜕皮或死亡。在显微镜下拍摄蜕皮和死蟹，并使用图像分析进行测量以评估生长和形态。死亡率主要与所有处理中的蜕皮有关，在所有处理中不同，在 pH 7.5 时最高，在环境 pH 时最低。在实验结束时，pH 7.5 的螃蟹在背甲长度和湿重方面都比环境 pH 下的螃蟹小；蜕皮后生长增量较小；有更长的换羽期。甲壳形态不受 pH 值处理的影响。实验室实验中生长的减少和死亡率的增加表明，较低的 pH 值可能会影响金王蟹种群和渔业。未来的工作应该检查幼虫的饲养条件是否会影响幼虫对低 pH 值的反应。