Blood that would freeze solid in any other fish runs freely through the veins of the Maori chief. This fish produces natural antifreeze proteins, a biochemical trick that prevents ice crystals from forming in its tissues. The adaptation allows it to thrive in waters near freezing. It is the kind of cold that would kill most other fish in minutes. It shares this superpower with its Antarctic relatives. They are a family of fish that have mastered the art of living where the ocean tries to turn solid. The chemistry is precise. The survival is absolute. You will not find this fish on a typical fishing trip. The Maori chief lives around New Zealand's remote subantarctic islands: the Aucklands, Campbell Island and the Snares. These windswept outposts sit in the path of the Roaring Forties. They are battered by storms and surrounded by some of the coldest, most productive waters on Earth. The fish forages along rocky reefs and kelp forests down to 100 metres. It uses a large mouth to suck prey from crevices. Twilight is mealtime. Small crustaceans, worms and smaller fish feature on the menu. The feeding is opportunistic. The timing is specific. Climate change poses a serious long-term threat to cold-adapted species like this one. As the subantarctic waters warm, the Maori chief may find itself with nowhere to go. It cannot move further south because there is no further south. The Antarctic continent stops it. Moving into warmer water would mean competing with species better suited to those temperatures. The retreat is impossible. The habitat is finite. The pressure is increasing. For now, populations around remote islands remain stable. There is no commercial fishery targeting this fish in New Zealand waters. But stability is not permanence. The ocean is changing faster than at any point in human history. Cold-water specialists are on the front lines of that change. The Maori chief swims on in its icy realm. It pumps antifreeze through its blood. It waits to see if the world warms up too much for its ancient adaptations to keep up. The future is uncertain. The present is cold.