Snapper are a highly abundant and iconic fish species in Aotearoa New Zealand, valued by a variety of stakeholders and tangata whenua. This popularity can see snapper populations placed under pressure from fishing. Robust science is therefore needed to inform management decisions.
In 1886 an onlooker observing a fishing operation in the Bay of Plenty said: “The whole sea as far as the eye could reach was covered with reddish brown patches, each an acre or more in extent, and denoting a solid shoal of fish from surface to near bottom”.
These fish were snapper, a seemingly endless resource, but fast forward 100 years and the situation became quite different. The development of industrial fishing methods had brought New Zealand’s snapper populations to the verge of collapse, and the Quota Management System was ushered in to halt the decline.
What has happened in the almost 30 years since these fishing restrictions were introduced? Part of the answer involves a variety of scientific research, much of it conducted by NIWA. This research has encompassed tagging of many thousands of fish to understand movement and estimate abundance, surveys to estimate the abundance of populations, cameras to observe how juvenile snapper utilise nursery habitats, aerial shots of activity in recreational fishing areas, assessment of changes in commercial catch rates to estimate abundance, and the reading and analysis of thousands of snapper ear bones (otoliths) to describe the age structure of populations.
Thirty years of management informed by a raft of scientific research appears to now be paying dividends. Snapper populations at the top of the South Island and on the west coast of the North Island have recently seen increases in abundance. In the Hauraki Gulf, commercial and recreational fishers are reporting improving catches, and NIWA scientists will soon be able to estimate whether the highly valued Hauraki Gulf snapper population is seeing a similar increase.
