Effects of elevated CO2 on ammonia excretion, metabolic rate, specific gravity, and yolk sac depletion in yellowfin tuna (Thunnus albacares) embryos and larvae

This study examines the impacts of near-future CO2 levels on early life stages of the yellowfin tuna (Thunnus albacares). Tuna embryos were obtained from a captive spawning broodstock population of yellowfin tuna at the IATTC Achotines Laboratory, Panama. Tuna were exposed to either control or 1900 microatmospheres CO2 directly after spawn and through the first 3 days of development as embryos hatched into yolk sac larvae. Metabolic rate, ammonia tissue accumulation, ammonia excretion, Rh protein mRNA expression, and specific gravity were quantified at various timepoints throughout development.