Age and growth of Cape stumpnose Rhabdosargus holubi (Pisces: Sparidae) in the Eastern Cape, South Africa

Farthing, Matthew William; James, Nicola C; Potts, Warren M

Title: Age and growth of Cape stumpnose Rhabdosargus holubi (Pisces: Sparidae) in the Eastern Cape, South Africa
Creator: Farthing, Matthew William
Creator: James, Nicola C
Creator: Potts, Warren M
Date Issued: 2016
Date: 2016
Type: text
Type: article
Identifier: http://hdl.handle.net/10962/122891
Identifier: vital:35365
Identifier: https://doi.org/10.2989/1814232X.2016.1156577
Description: Rhabdosargus holubi (Steindachner, 1881) is a small (maximum size = 450 mm total length; Heemstra and Heemstra 2004) sparid that is distributed along the south-east coast of Africa from St Helena Bay, South Africa, to Maputo, Mozambique (Götz and Cowley 2013). Spawning occurs in the nearshore marine environment primarily during winter, specifically May–August in KwaZulu-Natal (KZN) (Wallace 1975) and July–February in the South-Eastern Cape (Whitfield 1998). Individuals reach 50% sexual maturity at approximately 150 mm standard length (SL) in the Eastern Cape (Whitfield 1998). The early life stages are transported by the south-westward-flowing Agulhas Current, and recruit as post-flexion larvae and early juveniles into estuaries during late winter and early summer (Blaber 1974). The warm temperatures and high nutrient levels in estuaries favour fast growth (Blaber 1973a), and fish spend their first year of life in these environments, migrating back out to sea after reaching approximately 120 mm SL. Some individuals remain trapped in closed estuaries, where they may reach sizes greater than 200 mm SL (James et al. 2007a). Rhabdosargus holubi is the dominant estuarine-dependent marine teleost species recorded in permanently open and temporarily open/closed estuaries in the warm-temperate region, which spans the south, south-east and east coast of South Africa (Harrison 2005). The species is also an important component of the linefishery in many SouthAfrican estuaries (10–15.6% by number) (Pradervand and Baird 2002), particularly in Eastern Cape estuaries (Cowley et al. 2003). These figures underestimate the presence of R. holubi, as most individuals making use of estuaries are young, feeding predominately on filamentous macroalgae and diatom flora, and are generally too small to be caught with hook and line (De Wet and Marais 1990). James et al. (2007b) showed that R. holubi made up 34–92% of the annual seine-net catch in the East Kleinemonde Estuary. Rhabdosargus holubi is also important in the KZN shorebased linefishery, representing 4.6% of the total landed catch (Dunlop and Mann 2012).
Format: 8 pages
Format: pdf
Language: English
Relation: African Journal of Marine Science
Relation: Farthing, M.W., James, N.C. and Potts, W.M., 2016. Age and growth of Cape stumpnose Rhabdosargus holubi (Pisces: Sparidae) in the Eastern Cape, South Africa. African journal of marine science, 38(1), pp.65-71.
Relation: African Journal of Marine Science volume 38 number 1 65 71 April 2016 1814-2338
Rights: African Journal of Marine Science
Rights: Use of this resource is governed by the terms and conditions of the Taylor & Francis Online Terms and Conditions Statement

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Potts, Warren M (Prof)

RU Department of Ichthyology and Fisheries Science

RU South African Institute for Aquatic Biodiversity (SAIAB)

SDG 14. Life Below Water

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