Orange roughy form discrete aggregations which are susceptible to sequential depletion. It is not known if individual aggregations are reproductively distinct.

Orange roughy catches in Subarea VI increased rapidly and subsequently dropped (Figure 9.4.14.1). Orange roughy cpue in Subarea VI (Figure 9.4.14.2) has shown a strong declining trend since early 1990s. It is presumed that the aggregations were fished out. Landings have declined to low levels in each management area (VI, VII, and other) (Figure 9.4.14.1).

Orange roughy fisheries in Subarea VII have exhibited a similar pattern to that in VI (Figure 9.4.14.1). High catches have not been sustained by individual fleets and have dropped to low levels, suggesting sequential depletion. Orange roughy cpue in Subarea VII (Figure 9.4.14.3) has shown a strong declining trend since the early 1990s. It is unclear if there are unfished aggregations remaining in Subarea VII.

Factors affecting the fisheries and the stock

Regulations and their effects

Closed areas aimed at protecting orange roughy in Subdivisions VI and VII were implemented in 2005. Their effectiveness cannot be determined as their boundaries do not correspond to ICES rectangles.

Changes in fishing technology and fishing pattern

The fisheries for orange roughy on separate aggregations west of Ireland in Subarea VII peaked in 2002 and has declined markedly since (Figure 9.4.14.1). The fishery in Subarea VI has decreased dramatically since the depletion of the main aggregation on the Hebrides Terrace Seamount in the late 1980s and early 1990s (Figure 9.4.14.1). Faroese fisheries in Subareas VI, XII, and X and the Icelandic fishery in Division Va have ceased (Figure 9.4.14.1).