Oral

IAMAS

JPCM08 - Impacts of climate change on the ocean

Metabolic Responses of Clownfish (Amphiprion ocellaris) to Marine Heatwaves

Marine species are shifting their distributions in response to ocean warming, with significant implications for marine ecosystems. Alongside gradual warming, marine heatwaves (MHWs) - discrete periods of extreme regional ocean warming - have detrimental impacts on marine organisms, driving range shifts, habitat loss, drastic environmental changes, and disruptions in food webs. While some species can migrate to find new habitats, the majority of coral reef fish are highly site-attached and cannot avoid MHWs. False clownfish (Amphiprion ocellaris), representative of coral reef fish, spend their entire lives in an anemone after settlement. They are fully exposed to MHWs during both reproductive and developmental stages. This study investigates how the false clownfish respond to MHWs at physiological, genomic, and metabolomic levels. From hatching, larvae were exposed to simulated heatwave scenarios of 31��C and 32��C, alongside a control group at 28��C, for 100 days, followed by a 100-day acclimation period at 28��C. Resting metabolic rates were measured using respirometry, and fish samples were collected for transcriptomic and metabolomic analysis at three key time points: during the heatwave, immediately after, and 100 days post-heatwave. This talk will focus on respirometry data to examine how metabolic rates vary under different temperature treatments and whether clownfish show signs of acclimation once conditions returns to normal. Understanding these physiological responses is crucial for predicting how clownfish and other site-attached reef fish might cope with the increasing frequency of MHWs. These findings contribute to broader discussions on the resilience of coral reef ecosystems under climate change and the potential long-term consequences for fish populations and biodiversity.