Orange roughy is one of Australia's most valuable finfish However, its aggregating behaviour during spawning, slow growth, and longevity render it vulnerable to over-exploitation. Some stocks in New Zealand are at extremely low levels after only ten years of exploitation.

Good management is vital to maintaining orange roughy as a sustainable fishery. The model currently used for management estimates maximum sustainable yield (MSY) from estimates of natural mortality, M, and virgin biomass, Bo. Virgin biomass is estimated from the total catch to date and current stock size. Current stock size was the parameter about which there was greatest uncertainty.

Several methods of stock assessment appeared inadequate for orange roughy. Catch per unit effort indices are not very useful for highly aggregating species. Trawl surveys were also deemed to be of limited value because the fish occur largely over rough, untrawlable ground. Acoustic and egg production methods appeared feasible and were proposed to assess the orange roughy stock that spawns off eastern Tasmania. Egg surveys have been used world-wide to assess stocks of species such as anchovy, sardine, and mackerel (Lasker 1985; Lockwood et al .. 1981; Lo et al. 1992). However, until now, this method had only been used on one deepwater species, Dover sole (Lo et al . 1992).