DataSheet_1_The combined effects of acidification and acute warming on the embryos of Pacific herring (Clupea pallasii).docx

• Main Authors: Nicole R. Singh, Brooke Love, Christopher S. Murray, Kathryn L. Sobocinski, W. James Cooper
• Format: Dataset
• Language: unknown
• Published: 2023
• Subjects: Oceanography; Marine Biology; Marine Geoscience; Biological Oceanography; Chemical Oceanography; Physical Oceanography; Marine Engineering; Pacific herring; ocean acidification; temperature rise; climate change; critical thermal limits; oxygen consumption rates; heart rate; forage fishes; Ocean acidification
• Online Access: https://doi.org/10.3389/fmars.2023.1307617.s001; https://figshare.com/articles/dataset/DataSheet_1_The_combined_effects_of_acidification_and_acute_warming_on_the_embryos_of_Pacific_herring_Clupea_pallasii_docx/24848853

Anthropogenic climate change is projected to affect marine ecosystems by challenging the environmental tolerance of individuals. Marine fishes may be particularly vulnerable to emergent climate stressors during early life stages. Here we focus on embryos of Pacific herring (Clupea pallasii), an important forage fish species widely distributed across the North Pacific. Embryos were reared under a range of temperatures (10-16°C) crossed with two pCO 2 levels (600 and 2000 μatm) to investigate effects on metabolism and survival. We further tested how elevated pCO 2 affects critical thermal tolerance (CT max ) by challenging embryos to short-term temperature fluctuations. Experiments were repeated on embryos collected from winter and spring spawning populations to determine if spawning phenology corresponds with different limits of environmental tolerance in offspring. We found that embryos could withstand acute exposure to 20°C regardless of spawning population or incubation treatment, but that survival was greatly reduced after 2-3 hours at 25°C. We found that pCO 2 had limited effects on CT max . The survival of embryos reared under chronically warm conditions (12°, 14°, or 16°C) was significantly lower relative to 10°C treatments in both populations. Oxygen consumption rates (MO 2 ) were also higher at elevated temperatures and pCO 2 levels. However, heart contraction measurements made 48 hours after CT max exposure revealed a greater increase in heart rate in embryos reared at 10°C compared to 16°C, suggesting acclimation at higher incubation temperatures. Our results indicate that Pacific herring are generally tolerant of pCO 2 but are vulnerable to acute temperature stress. Importantly, spring-spawning embryos did not clearly exhibit a higher tolerance to heat stress compared to winter offspring.