Bottomfish Survey Underway Across Hawai‘i

The NOAA Ship Oscar Elton Sette is home to scientists from the Pacific Islands Fisheries Science Center during the fall survey. PC: NOAA

Researchers from the Pacific Islands Fisheries Science Center and local cooperative research fisheries have conducted the bottomfish survey in Hawaiʻi every year since 2016. The bottomfish survey provides estimates of bottomfish abundance—independent of fisheries—to assess the status of the Deep-7 bottomfish stock. The Deep-7 are opakapaka, onaga, ʻehu, gindai, kalekale, lehi and hapuʻupuʻu.

Throughout September 2019, the NOAA Ship Oscar Elton Sette will be home to a group of scientists deploying deep-water camera systems. These cameras are used to observe, count, and measure Deep-7 bottomfish at 176 locations around the main Hawaiian Islands. Scientists will start at the island of Niʻihau and work their way to the island of Hawaiʻi. They will spend their days on small boats deploying their cameras to depths where bottomfish live—between 250–1,300 feet. Researchers aboard the Sette will deploy additional cameras after the small boats depart. Each camera sits on the seafloor for 15 minutes before the researchers recover it and deploy it in a new location. Nothing is left on the bottom.

At the end of the survey, a team of researchers at the Pacific Islands Fisheries Science Center analyze the videos. They identify, count and measure bottomfish. Scientists turn these observations into abundance and biomass estimates, which they use to continually improve the Deep-7 stock assessment. The assessment provides managers with the best available information to set commercial catch limits and help ensure a sustainable Deep-7 fishery in the Hawaiian Islands.

At the same time, cooperative research fishers will conduct scientific hook-and-line fishing operations from local commercial bottomfishing vessels. These cooperative research fishers will sample at an additional 303 stations around the main Hawaiian Islands during September and October. They report the size and species of each fish they catch. They also provide their catch to the Pacific Islands Science Center’s Life History Program. The program uses the samples to determine growth rates, the size at which fish reach sexual maturity and become capable of spawning, and many other life-history characteristics. All of this information improves the Deep-7 bottom fish stock assessment.

At the end of the survey, a team of researchers at the Pacific Islands Fisheries Science Center analyze the videos. They identify, count, and measure bottomfish. Scientists turn these observations into abundance and biomass estimates, which they use to continually improve the Deep-7 stock assessment. The assessment provides managers with the best available information to set commercial catch limits and help ensure a sustainable Deep-7 fishery in the Hawaiian Islands.

At the same time, cooperative research fishers will conduct scientific hook-and-line fishing operations from local commercial bottomfishing vessels.  These cooperative research fishers will sample at an additional 303 stations around the main Hawaiian Islands during September and October. They report the size and species of each fish they catch. They also provide their catch to the Pacific Islands Science Center’s Life History Program. The program uses the samples to determine growth rates, the size at which fish reach sexual maturity and become capable of spawning, and many other life-history characteristics. All of this information improves the Deep-7 bottomfish stock assessment.