This research develops stable-isotope tools to measure how microbes—the Earth’s “lungs”—breathe CO₂ in and out. Microbes are massively abundant and shape global climate. Findings show deep subsurface environments slowly emit CO₂, a process that may influence future climate dynamics as human-driven environmental changes accelerate.

Feathers and blood preserve detailed biological records of Tītī stress, diet, and environment across both New Zealand and the North Pacific. By analysing hormones and stable isotopes in modern and historical samples, this research reveals how climate change affects Tītī populations and identifies which groups are most vulnerable, guiding future conservation efforts.