Anecdotal evidence suggests a shrinking in the historical range, with the catch of
P. praeorbitalis in southern Mozambique now comprising <1% of the total linefish catch (van der Elst
et al. 1994). Commercial catches suggest that this species is most abundant on the KwaZulu-Natal south coast and off the former Transkei region of the Eastern Cape (Garratt
et al. 1994). Catch per unit effort (CPUE) of
P. praeorbitalis declined significantly off KwaZulu-Natal by ~65% from 127 kg per man per year between 1928-1941 to 17 kg per man per year
between 1985-1992 (Garratt
et al. 1994, Penney
et al. 1999). A per-recruit stock assessment conducted in 2004 showed that the stock had been reduced to approximately 21% of spawning biomass per recruit (SBPR) despite the implementation of catch restrictions in 1984 and 1992, including minimum size limits and bag limits (Mann
et al. 2005). The stock status of
P. praeorbitalis was considered to be even lower than was estimated because of the lack of sufficient samples and a poorly estimated mortality rate (Mann and Garratt 2012). Total reported commercial catches have dropped from around 14 tonnes/year to two tonnes/year between 1985 and 2007, and targeted CPUE declined from 0.08 to 0.04 kg per man per hour over this period (NMLS unpublished data). Catch composition of
P. praeorbitalis declined from 2.9% of total commercial KwaZulu-Natal line-fish catches from the period 1928-1941 to 1.6% in the period 1985-1992 (Garratt
et al. 1994). Significant change in mean size of this species was observed from the period 1979-1981 (35.7 cm FL) to the period 1990-1992, with recent catches containing fewer larger fish (Garratt
et al. 1994). The mean size had increased to 39.7 cm FL during 2003, but this was likely to have been influenced by the increase in the minimum size limit from 30 cm to 40 cm TL (Mann
et al. 2005). Fish in the Richards Bay area were significantly larger than those on the KwaZulu-Natal south coast (Garratt
et al. 1994, Mann
et al. 2005).
The sex ratio of this species was heavily skewed towards females due to the removal of larger male fish and increased with increasing latitude from Richards Bay (1:2.6) to Ramsgate (1:99) (Garratt et al. 1994). A male:female sex ratio of 1:9 for P. praeorbitalis was observed primarily on the KwaZulu-Natal south coast (Mann et al. 2005).
Commercial data show that since 2000 commercial fishing effort has declined dramatically in the South African line-fishery, from approximately 3,000 to 450 vessels in line with the long-term fisheries rights allocation process implemented in 2006 (Depaertment of Agriculture, Forestry and Fisheries 2012).
