Ocean Jacket (Nelusetta ayraud) or leather jackets (aka kawahagi) is the largest species of Leatherjacket of southern Australia that can reach 700 mm in length. It is a demersal, schooling species that is distributed from central Queensland southwards, along the southern coastline and continental shelf and then up to the central coast of Western Australia. The species occurs across a wide depth range from very shallow to >350 m, due to off-shore movement associated with ontogenetic development. The juvenile Ocean Jackets occur in shallow, coastal bays whilst the adults are located over flat, sandy bottom in offshore, continental shelf waters >60 m in. Stock structure throughout the broad distribution is unknown, but must be influenced by off-shore, ontogenetic migration, and the capacity of adults for significant long-distance movement. The Ocean Jacket is a dichromatic species of leatherjacket that is fast-growing and short lived, as determined from ageing work from rings in vertebrae. Most fish from the commercial fishery were 3 – 6 years of age, whilst the oldest male was seven years and oldest female was nine years old. Reproductive maturity was attained from 2 – 4 years of age, associated with size-at-first maturity of 310 mm, and corresponded with the timing of off-shore migration. In South Australia, spawning occurs in April and early May in waters >85 m depth in off-shore waters.
South Australia – Sustainable