Multiple measures of thermal performance of early stage Eastern rock lobster in a fast-warming ocean region

To date, many studies trying to understand species’ climate-driven changes in distribution, or ‘range shifts’, have each focused on a single potential mechanism. While a single performance measure may give some insight, it may not be enough to accurately predict outcomes. Here, we used multiple measures of performance to explore potential mechanisms behind species range shifts. We examined the thermal pattern for multiple measures of performance, including measures of aerobic metabolism and multiple aspects of escape speed, using the final larval stage (puerulus) of eastern rock lobster Sagmariasus verreauxi as a model species. We found that aerobic scope and escape speed had different thermal performances and optimal temperatures. The optimal temperature for aerobic scope was 27.5°C, while the pseudo-optimal temperature for maximum escape speed was 23.2°C. This discrepancy in thermal performance indicators illustrates that one measure of performance may not be sufficient to accurately predict whole-animal performance under future warming. Using multiple measures of performance and appropriate modelling techniques may lead to a more accurate prediction of future range shifts, including the timing and extent of climate-driven species redistribution.