Relationships between behavioral and physiological performance under elevated CO₂ in marine fishes

• Main Author: Laubenstein, Taryn Diane
• Format: Thesis
• Language: unknown
• Published: 2019
• Subjects: Ocean acidification
• Online Access: https://researchonline.jcu.edu.au/63887/1/JCU_63887_Laubenstein_2019_thesis.pdf

Over the past decade there has been a concerted effort to determine how ocean acidification will affect a range of fitness-related traits in marine fishes, with studies often finding negative impacts on either behavioral or physiological performance. Until recently, most studies have focused on the mean responses of the sampled populations to ocean acidification. However, there is a growing recognition of the value in examining individual variation in responses. This can highlight individuals that are best suited to survival in future conditions. Identifying these individuals, however, can be challenging, because performance is not always consistent across all traits. Indeed, correlations can exist between traits that could either help or hinder survival at the individual level, and even affect the ability of marine fishes to adapt to ocean acidification. For instance, if two traits are negatively correlated with respect to the fitness landscape, then selection on one trait will diminish the other, slowing the rate of adaptation, and vice versa. Thus, identifying correlations among key traits is a crucial step towards understanding the potential of marine species to adapt to future climatic conditions. This thesis seeks to identify such correlations by examining the relationship between behavioral and physiological performance in marine fishes and determining how environmental conditions and parental effects might alter this relationship. Theory predicts that environmental stressors can alter relationships between behavioral and physiological traits, either revealing or masking significant relationships. While both ocean acidification and warming have been found to affect behavioral and physiological performance in marine fishes, they can often interact in complex, non-additive ways, making it difficult to predict their combined impacts on marine fishes. Therefore, in Chapter 2 I explored the relationship between behavioral and physiological performance in a juvenile reef fish, Acanthochromis polyacanthus, ...