Whole Life-Cycle CO2 × Temperature Effects on Fecundity and Oocyte Recruitment in the Atlantic Silverside (Menidia menidia)

• Other Authors: Concannon, Callie (Creator), Baummann, Hannes (Major Advisor), Matassa, Catherine (Associate Advisor), McBride, Richard (Associate Advisor), University of Connecticut (Degree grantor)
• Format: Text
• Language: unknown
• Published: University of Connecticut 2020
• Subjects: Ocean acidification
• Online Access: http://hdl.handle.net/11134/20002:860652815; https://digitalcollections.ctstatelibrary.org/islandora/object/20002%3A860652815/datastream/TN/view/Whole%20Life-Cycle%20CO2%20%C3%97%20Temperature%20Effects%20on%20Fecundity%20and%20Oocyte%20Recruitment%20in%20the%20Atlantic%20Silverside%20%28Menidia%20menidia%29.jpg

Experimental ocean acidification research has uncovered many traits in marine organisms that are affected by elevated CO2 levels, but often for only specific life stages, and even collectively covering only a small fraction of an organisms’ life. The annual life cycle of the Atlantic silverside (Menidia menidia) makes it an ideal model for studying whole life effects of high CO2 and temperature environments in coastal fishes. Here, I experimentally study the consequences to growth and oocyte production from whole life exposure to high CO2 and temperature in Atlantic silverside populations lab-reared from fertilization to reproductive maturity. Wild adult Atlantic silversides were captured via beach seine in the spring of 2018 and strip-spawned. Their offspring were reared to their first major spawning event under ambient (~400 μatm) or high (~2,200 μatm) pCO2 conditions and either 17°C, their natural spring temperature, or 24°C, their end of summer, optimal rearing temperature. Male and female Atlantic silversides grew larger and heavier but had significantly smaller gonadosomatic indices. Females were largely impacted by elevated temperatures and no pCO2 effect. The pCO2 effect for males was temperature-dependent and reacted synergistically with elevated temperatures. Elevations of both stressors significantly increased potential fecundity, relative fecundity decreased when exposed to elevated temperatures at both pCO2 conditions, and neither stressor impacted mass-corrected fecundity. Elevations of both stressors synergistically decreased maximum oocyte size. Elevated pCO2 affected oocyte probability density distributions differently depending on temperature treatments. At 17°C, elevated pCO2 negatively affected quantiles resulting in smaller oocytes, whereas at 24°C, all but one quantile were positively affected by elevated pCO2 resulting in larger oocyte sizes. Oocyte sizes of the earlier stages of oocyte development largely increased under elevated temperatures, whereas the later stages were not affected by ...