Cells are able to sense and respond to oxygen deprivation by modifying their metabolism to cope with low oxygen levels. The hypoxia response not only plays a crucial role for survival under changing environmental conditions, but is also of great significance for human diseases, including cancer, ischemia, and stroke. In Drosophila larvae, hypoxia induces tracheal growth and branching, resembling the angiogenic response induced by hypoxic tumor cells. We use hypoxia-induced tracheal growth in Drosophila as a paradigm to address the interrelation between cellular metabolism and gas exchange. First, we ask how mitochondrial rates of various larval tissues influence the recruitment of tracheal cells through fibroblast growth factor (FGF) signaling. Second, we analyze how metabolism in the target tissues responds to changes gas exchange rates. Third, we develop tools to visualize hypoxic signaling in situ in living larvae. The aim of this work is to provide a better understanding of hypoxic effects during development, with implications for tumor metabolism and the regulation of angiogenesis by metabolic cues.