In 1998, this fungus was identified as the cause of global amphibian declines. It reached New Zealand shortly after. Batrachochytrium dendrobatidis, or Bd, attacks the skin of frogs. For amphibians, skin is not just a covering. It is a respiratory organ. It regulates water and salt balance. When Bd infects the skin, it thickens and disrupts these critical functions. The frog essentially suffocates or suffers cardiac arrest due to electrolyte imbalance. The disease is called chytridiomycosis. It has driven dozens of species to extinction worldwide. In New Zealand, our native frogs (Leiopelma) are ancient lineages, unchanged for millions of years. They are particularly vulnerable because they lack the immune adaptations of more recent amphibian groups. So far, mass die-offs have not been recorded in wild Leiopelma populations, but the pathogen is present. It lurks in water bodies and on moist skin. Transmission occurs through direct contact or via contaminated water. The fungus thrives in cool, moist environments, which describes much of New Zealand's forest floor. Conservationists monitor frog populations closely. Biosecurity measures restrict movement between catchments to prevent spread. The threat is silent. There are no visible lesions until it is too late. The frog simply stops moving. The potential for catastrophic loss remains high. These frogs are living fossils. Their disappearance would sever a link to Gondwana. The fungus does not care about history. It only cares about host availability. Vigilance is the only tool available. Keep waterways clean. Do not move frogs between sites. The stakes are geological.