Ocean warming is affecting marine species worldwide, with one of the most observed changes being alterations to species geographical distributions. Understanding what drives these range shifts is key to predicting what may happen with future warming. This study takes a mechanistic approach to understanding climate-driven range shifts, looking at the metabolic and escape responses of spiny rock lobster and how they may change under different temperature scenarios. We examined the metabolic physiology and escape response of the puerulus and juvenile stages of Jasus edwardsii, a common Tasmanian species of spiny rock lobster, and Sagmariasus verreauxi, a species of spiny rock lobster extending its range into and further south in Tasmania. The puerulus stage of the spiny rock lobster life cycle is an important transitional stage between the larval and juvenile stages and understanding how ocean warming may affect their aerobic and swimming capacity allows us to better predict future scenarios of population dynamics. Jasus edwardsii individuals of both life stages were tested at 16, 18, 20, 22, 24 and 26°C, and S. verreauxi individuals were tested at 22, 24, 26, 28 and 30°C. Intermittent flow respirometry was used to determine aerobic scope (AS), excess post-exercise oxygen consumption (EPOC) and recovery times. Escape velocities were determined from high speed stereo-video footage. The comparison between the physiologies of the two species indicates that S. verreauxi have higher thermal tolerances than J. edwardsii, and this may facilitate further expansion of this range-shifting species into Tasmanian waters with future ocean warming.