KOSMOS 2020 Peru mesocosm study on ecosystem responses to different light and upwelling intensities: fish larvae growth and survival

• Main Authors: Goldenberg, Silvan Urs, Sswat, Michael, Aguirre-Velarde, Arturo, Ofelio, Claudia
• Format: Dataset
• Language: English
• Published: PANGAEA 2024
• Subjects: Age; AQUACOSM; Calculated; Carbon/Nitrogen ratio; Carbon mass; chita; Coastal Upwelling System in a Changing Ocean; CUSCO; DATE/TIME; Day of experiment; Dry mass; Eastern Boundary Upwelling systems; Event label; Fish; standard length; total length; fish larvae; Humboldt Current System; KOSMOS; KOSMOS_2020; KOSMOS_2020_Laboratory-Baseline; KOSMOS_2020_Mesocosm-M1; KOSMOS_2020_Mesocosm-M2; KOSMOS_2020_Mesocosm-M3; KOSMOS_2020_Mesocosm-M4; KOSMOS_2020_Mesocosm-M5; KOSMOS_2020_Mesocosm-M6; KOSMOS_2020_Mesocosm-M7; KOSMOS_2020_Mesocosm-M8; KOSMOS_2020_Mesocosm-M9; KOSMOS Peru; Laboratory measurement; MESO; Mesocosm experiment; Mesocosm label; Network of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean; Nitrogen mass; Peruvian anchovy; plankton food web; Sample type; Species; unique identification; unique identification (URI); Taxa; Treatment; Treatment: light condition; Type of study; Wet mass; Arctic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.967054; https://doi.org/10.1594/PANGAEA.967054

Fish larvae performance during the mesocosm experiment in the Peruvian upwelling system near Lima from February-April 2020. Light (ambient = high vs. reduced = low) was manipulated from the beginning (day 0) and upwelling (0 to 60% deep water addition) two weeks into the experiment (day 13). Larvae Peruvian anchovy (Engraulis ringens, 24 days-post-hatch) and chita (Anisotremus scapularis, 44 days-post-hatch) reared in the laboratory were introduced shortly after (day 19). Fish mortality was monitored continuously via carcasses sinking to the sediment trap. This 'Sediment' category of samples is only reliable for counts, while many length and weight measures will be inaccurate due to degradation. While live fish were subsampled during the experiment, not enough individuals could be caught for a proper analysis. Instead, the main sampling of live fish was at the end of the experiment (day 36). Most fish had reached the late larvae or early juvenile stage by that time. Fish length and wet mass were assessed for all these individuals. A subsample of both species was used to establish wet to dry to C to N mass relationships. These were applied to convert wet mass into dry, C and N mass for all other fish. Methodological details in Goldenberg et al. and Thielecke et al. (manuscripts in progress).