At some point in the twentieth century, New Zealand divers worked out that a large, slow-moving fish occupying the same reef cave for decades is easy to spear. Epinephelus daemelii obliged entirely. By the time full protection arrived in 2012, mainland populations had been reduced to a state described by researchers as functionally depleted. The fish was present in considerable numbers before European settlement. It is now rare on every accessible mainland reef where it was once reliable. Epinephelus daemelii is the largest grouper in New Zealand waters. Adults are grey to black overall. Five oblique pale bands cross the body. These are vivid in juveniles and fade in large adults. Some old individuals become almost uniformly black. The head is substantial. The mouth is wide. The maximum reported size is around two metres and up to 180 kilograms. Fish approaching those dimensions are now essentially confined to the Kermadec Islands Marine Reserve. Protection has been in place long enough for some individuals to approach their biological ceiling. On mainland reefs, a fish over 50 centimetres is now unusual. The species has several qualities that made it particularly vulnerable to spearfishing. It is site-faithful. It returns to the same caves and overhangs across decades. It is curious and largely unafraid of divers. This characteristic is noted in the research literature. It is confirmed by anyone who has encountered one at the Kermadecs. It reaches sexual maturity late. It has a low reproductive rate relative to most reef fish. A population does not recover from heavy exploitation quickly. For a species with these characteristics, some decades may not be enough. Juveniles are recorded as far south as Hokitika on the west coast and Palliser Bay in the east. They are carried by larval drift from spawning adults further north. Whether mainland New Zealand supports any self-sustaining breeding population outside the Kermadecs is uncertain. Most mainland individuals are thought to be recruits. They arrive, grow for a few years, and do not reliably reproduce in the conditions available to them. Full protection under the Wildlife Act has been in place since 2012. Recovery on mainland reefs is slow and uneven. This is entirely consistent with the biology of a fish that takes many years to mature. It does not compensate for losses with high reproductive output. The spotted black grouper is still there. Whether it returns to the abundance Māori knew before the advent of spearguns is a question that will take a very long time to answer.