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The red stumpnose Chrysoblephus gibbiceps (Sparidae) is a South African endemic seabream that has been severely depleted by fishing. A total of 678 C. gibbiceps were sampled by line and trawl fishing for a study of their morphology, age, growth, reproduction and diet. In addition, catch records from three time-periods since 1897 were interrogated for distribution patterns and movement behaviour. The sex ratio was 1.5:1 in favour of males. The length–weight relationship, W = 9.32 × 10−5LF2.811, indicates hypoallometric growth. The bulbous head of large males is a secondary sexual characteristic. A von Bertalanffy growth model was fitted to age data obtained using otolith analyses: LF = 429.9 × (1 – e−0.113(t – (−3.799)). The maximum recorded age was 48 years, which is among the highest in seabreams, though the species matures after only 3 years. The gonadosomatic index (GSI) of ripe females (4.5%) was comparatively low, and the two-month-long early-summer spawning season was short compared with that of other sympatric seabreams. The very low GSI of ripe males (1.6%) suggests courtship battles and polygamy. The species feeds over low-profile reefs and consolidated sediments. The principal prey are ophiuroids. Although its trophic level is 3.7, C. gibbiceps has a low-nutrition diet. Historical and current catch data confirm a distribution from Cape Point (southeastern Atlantic) to southern KwaZulu-Natal Province (western Indian Ocean). There is evidence for localised migratory patterns, now partly lost due to severe population depletion. Whereas protogyny and resident behaviour have been suggested as traits that render seabreams vulnerable to fishing pressure, C. gibbiceps is a shoaling gonochorist that has collapsed due to fishing. [ABSTRACT FROM AUTHOR]

Stomach content analyses and measurements of gillraker morphology were used to assess the diet and feeding ecology of the East Coast redeye round herringEtrumeus wongratanaiand provide data for comparisons with other small pelagic fishes off South Africa. Samples were collected by jigging from a kayak off Scottburgh, KwaZulu-Natal (KZN), over the period July 2013–May 2014. In total, 66 stomachs (containing 4 407 prey items) and 66 gill arches were examined. Stomach content analyses indicated that East Coast redeye round herring, at the time of sampling, fed on large (1 500–2 500 µm) particles, with ∼2 500 µm particles making the greatest contribution to dietary carbon. The species feeds on larger particles than do anchovyEngraulis encrasicolusand sardineSardinops sagax, but on particles of a similar size to those consumed by West Coast redeye round herringEtrumeus whiteheadi. There were significant differences in mean gillraker gaps between East Coast redeye round herring and both sardine and anchovy, but not between East Coast and West Coast redeye round herring. The differences in gillraker gaps between East Coast redeye round herring, sardine and anchovy are indicative of resource partitioning through differential feeding, based on zooplankton size. The data suggest that there is no resource partitioning between East and West coast redeye round herring, indicating that competition is likely to occur between them. However, such competition is minimised by limited spatial overlap between these two species. [ABSTRACT FROM AUTHOR]