Stock Assessment of Uku in Hawai'i, 2020

This report presents the stock assessment of the ukupalu snapper, commonly known as “uku”, in the main Hawaiian Islands (MHI) covering the period from 1948 to 2018. Uku is a wide-ranging reef-associated  snapper (family  Lutjanidae) that is found between 35° N and 31° S from East Africa to Hawai'i. The scientific name for this species is Aprion virescens and it goes by several common English names in other regions, typically “green jobfish” or “gray snapper.”

The Hawai'i uku population was first assessed with other snappers using a catch-only method applied at the family level (Sabater & Kleiber 2013). That assessment determined that snappers were not overfished in the MHI. In 2017, uku were assessed at the species-level using a length-based mortality model and a relatively simple numerical population model to obtain fishing mortality rates and spawning potential ratios (SPR).

Using this approach, it was determined that this stock was not experiencing overfishing (Nadon 2017), with a spawning potential ratio of 0.33, which was above the 0.3 limit defining overfishing

Nadon MO, Sculley M, Carvalho F. 2020. Stock assessment of uku (Aprion virescens) in Hawai'i, 2020. U.S. Dept. of Commerce, NOAA Technical Memorandum NOAA-TM-NMFS-PIFSC-100, 119 p.  https://doi.org/10.25923/57nb-8138.