October 12th, 2016 — State and federal fishery officials have struggled for decades to determine how many deep-sea bottomfish like onaga and opakapaka are in Hawaiian waters, basing stock assessments on the amount of groupers and snappers caught by commercial fishermen.
The method has made it difficult to assess the health of the fishery and what limits to set on the amount of bottomfish that can be reeled in each year, which affects whether these popular fish appear on the menu and how much they cost if they do.
But scientists with the National Oceanic and Atmospheric Administration say a five-year joint effort with state officials, fishermen and others to improve their stock-assessment methods is about to pay off thanks in large part to a newly developed underwater camera system.
Twelve researchers are set to embark on a 15-day mission to take photos of bottomfish using the 70-pound rigs at 66 locations around the main Hawaiian Islands. Scientists will then spend weeks or possibly months counting the fish in the photos, determining their length and identifying the species, which are found at depths ranging from 300 to 900 feet.
That information will be combined with data that six commercial fishermen are currently collecting through a standardized survey method that involves them fishing at certain areas for a set period of time using the same bait.
The initial data analysis is expected in January, said Benjamin Richards, NOAA fishery biologist and the survey’s lead scientist. A final analysis is expected a few months after that. It will ultimately end up being used in the 2018 stock assessment, he said, the first major update in four years and most comprehensive to date.