Hypoxia , defined as a dissolved oxygen concentration (DO) below 2 mg L-1, can be a significant stressor to aquatic organisms, particularly those that are sessile like marine bivalves , who canno t avoid such conditions. Estuarine and coastal environments are more susceptible to hypoxia as anthropogenic nutrient loading fosters algal blooms that deplete oxygen upon decay, putting bivalves at a greater exposure risk of hypoxia. Furthermore, ocean warming exacerbates the challenges of hypoxia for ectot hermic bivalves as their metabolic demand rises with temperature, yet meeting this demand becomes increasingly difficult under low oxygen conditions. The plasticity of bivalves to alter their physiology in response to environmental change plays a significant role in understanding their resilience and survival to hypoxia. Furthermore, environmental stress may affect various life stages differently , thus exploring the plasticity and tolerance of different life stages is imperative. The aim of this study is to explore the plasticity of juvenile and adult eastern oysters (Crassostrea virginica) to extended hypoxia under warm water temperatures. Juveniles and adults were held under either normoxic conditions or hypoxic conditions for a three-week period at temperatures reflective of summer water conditions in Atlantic Canada (~24ºC). The metabolic rate, anaerobic capacity , mitochondrial activity, and feeding rate of oysters were measured before, during, and after the experiment to understand the efficiency and rate of plasticity at multiple levels of biological organization. Preliminary results suggest that both juvenile and adult oysters exhibit physiological plasticity to low oxygen conditions, though, over an extended period, adults are more resilient than juveniles . This study highlights the potential for oysters across different life stages to acclimate and survive under extended periods of low oxygen, useful information for aquaculture management practices.