The ideal candidate for the job: how epaulette sharks ( Hemiscyllium ocellatum ) have emerged as a model for climate-ready shark conservation

Sharks and rays are among the most threatened vertebrates; yet, mechanistic data to predict their responses to climate change remain sparse. We argue that the epaulette shark (Hemiscyllium ocellatum) is a tractable candidate species for conservation physiology because it is small and benthic, abundant on Great Barrier Reef flats, exceptionally tolerant of hypoxia and acidification conditions, and amenable to captive breeding and experimental work across life stages. Its distinctive appearance, accessibility and calm disposition also make it an effective flagship species for public engagement and reef conservation. A long-term breeding colony and field access have enabled experiments spanning ocean acidification, hypoxia and warming. Across studies, epaulette sharks show robust maintenance of routine behaviours in both adult and juvenile stages under elevated CO2, consistent with physiological traits that buffer pH changes. In contrast, warming imposes clear constraints, especially early in ontogeny. Embryos hatch earlier and smaller, aerobic scope narrows, metabolic costs rise, recovery is delayed, growth is impaired, and mortality risk increases at the upper thermal range. Adults and juveniles retain notable hypoxia tolerance, reflecting nocturnal tidepool conditions; yet, performance trade-offs may emerge when warming and low O2 co-occur. Together, findings so far illustrate how a resilient species can still harbour critical vulnerabilities under projected climate change conditions. Here, we outline how the epaulette shark can anchor comparative work to derive transferable thresholds (e.g. temperature–oxygen safety margins), test cross-tolerance mechanisms and validate field-relevant biomarkers for monitoring population health. Management applications follow directly, allowing habitat-specific thermal and oxygen limits for shallow flats and nursery areas to be identified, informing heatwave response and water-quality targets, and refining husbandry and welfare guidelines for research and public aquaria. While a site-attached benthic model will not capture constraints faced by pelagic elasmobranchs, leveraging this tractable flagship species to bridge mechanistic understanding and management decision points can enhance forecasts for other reef-associated chondrichthyans and support climate-ready conservation strategies.