Standardizing deoxygenation studies in coral biology.

Deoxygenation, the global loss of biologically available oxygen (O2) from the world's oceans, presents a pervasive and intensifying threat for reef-building corals that will require coordinated efforts to understand and manage. However, recent expansion of coral deoxygenation experimentation has produced methodological gaps, limiting collective knowledge generation. Here, we show that growing divergence in this field arises primarily from differences in focal phenotypes, deoxygenation exposures, and experimental execution that together prevent biological from technical variation from being disentangled between studies. To address this, we propose a series of recommendations to establish the foundation for a future standardized framework for coral deoxygenation methodology. Such efforts are critical to establish a robust consensus of scientific data to support effective management of reef deoxygenation. Waiting decades for diverging methodologies to prompt a call for standardization may be imprudent given the urgent threat of deoxygenation and the abundant methodological divergence present in coral deoxygenation experimentation.