Understanding relationships between fished predators and trophically linked species is essential to managing the indirect impacts of fishing. Across temperate rocky reefs globally, the overexploitation of sea urchin predators often results in an ecosystem shift from kelp forest to ‘urchin barrens’. Snapper (Chrysophrys auratus) are widely considered an important predator of the sea urchin or kina (Evechinus chloroticus) on northern New Zealand reefs, yet surprisingly very little is known about their interactions. Recent findings show a significant contribution of kina to snapper diet and a strong correlation between snapper fork length and the size of kina found in snapper guts, with indications of a snapper gape limitation allowing larger individuals to consume larger kina. Underwater cameras were used to confirm suspected predation patterns, and tethered kina were deployed in and outside marine protected areas to assess how predation rates changed between areas with known populations of large and abundant snapper (protected areas) relative to areas with sparser populations and smaller individuals (unprotected areas). Confirmation of the importance of large snapper as urchin predators on northern New Zealand reefs would emphasise the need for fisheries management to prioritise the protection of larger, more influential snapper to facilitate kelp recovery.