Seawater carbonate chemistry and survival and growth of young‑of‑the‑year golden king crab (Lithodes aequispinus)

• Main Authors: Long, W Christopher, Swiney, Katherine M, Foy, Robert J
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: Aleutian_Islands; Alkalinity; total; standard deviation; Animalia; Aragonite saturation state; Arthropoda; Benthic animals; Benthos; Bicarbonate ion; Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carapace; length; Carapace width; Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Coast and continental shelf; Comment; Containers and aquaria (20-1000 L or < 1 m**2); Date; EXP; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Identification; Laboratory experiment; Lithodes aequispinus; Mortality/Survival; North Pacific; OA-ICC; Golden King Crab; Kodiak; Ocean acidification; Alaska
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.939835; https://doi.org/10.1594/PANGAEA.939835

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.