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Argyrozona argyrozona is endemic to South Africa between Table Bay and KwaZulu-Natal (Smith and Heemstra 1986) with the core area of distribution between Cape Point and Kei Mouth (Heemstra and Heemstra 2004). The depth range for adults of this species is 50 to 200 m and 10 to 40 m for juveniles (Brouwer and Griffiths 2005).
Argyrozona argyrozona is currently considered to be recovering (Kerwath and Winker 2013). Biomass is estimated to be at around BMSY (Winker et al. 2014). Inshore trawl CPUE for A. argyrozona for the period 1985 to 1994 was 2.8% and 2.4% of the historical peaks from the period 1944 to 1954 for the Southeastern Cape and the Southern Cape, respectively. Fishery independent data from surveys conducted from 1931 to 1933 and 1987 to 1993 indicate that CPUE for A. argyrozona declined by 75% between the two periods (Griffiths 2000). This species fell below the 25% critical level for the Southwestern Cape and Southern Cape for 1986 to 1998 indicating that A. argyrozona was severely over-exploited (Griffiths 2000). However, CPUE has improved substantially as a result of the commercial effort reduction with the long-term rights allocation in 2006 and the removal of larger deck boats from the fishery (Winker et al. 2012, 2013). The stocks are showing steady signs of recovery (Winker et al. 2014).
Recent total catch of A. argyrozona has declined from a peak in 1991 of 1,300 tonnes to 200 tonnes in 2002 (decline of ~85%) and over the same period, targeted CPUE remained stable at around two kg/man hr. Subsequently CPUE has improved (National Marine Linefish System, unpublished data).
Both stocks (Western and Eastern Cape) have demonstrated declines in CPUE of over 95% during the 20th Century (Griffiths and Mann 2000) and across the range and fisheries (trawl and line). Per-recruit analysis (Brouwer and Griffiths 2006) suggested that both stocks are heavily over-fished with spawning biomass per recruit between 11.9% and 22.4% and egg per recruit between 6.6% and 14.1%. Commercial data show that since 2000 commercial fishing effort has declined dramatically in the entire linefishery from approximately 3,000 to 450 vessels in line with the long-term fisheries rights allocation process implemented in 2006 (Department of Agriculture, Forestry, and Fisheries 2012).
In the Southwestern Cape, catches of this species declined consistently in the early 20th century but peaked in the Southern Cape during the period 1927 to 1931 as a result of the introduction of motorized vessels which facilitated offshore exploitation (Griffiths 2000). Argyrozona argyrozona contributes on average 3% to the total linefish catch with no discernible trend in the last ten years (National Marine Linefish System unpublished data) but is the most important sparid by catch volume in the commercial linefishery in South Africa (Kerwath and Winker 2013). This species is also caught in the demersal trawl bycatch, especially by the inshore component of this fishery which is significant at an estimated 80% of the linefish catch (Attwood et al. 2011).
Offshore operations that target A. argyrozona are unlikely to be sustained as the catch primarily consists of large adults (Marine and Coastal Management, unpublished data) and could have a substantial impact on the remaining spawner biomass if these operations continue in this manner. Vessels moved farther offshore with the decline of inshore linefish species, including geelbek, seventyfour and silver kob, which resulted in the increased importance of other species including A. argyrozona throughout the 20th century. Argyrozona argyrozona comprised 11% of the catch composition in a fishery independent survey conducted from 1931 to 1933 and 10% of the composition from 1987 to 1993 (Griffiths 2000).