© Baker, J.L. (2009) Marine Species of Conservation Concern in South Australia Full citation Baker, J.L. (2009) Marine Species of Conservation Concern in South Australia: Volume 1 - Bony and Cartilaginous Fishes. Report for the South Australian Working Group for Marine Species of Conservation Concern. J. Baker (consultant); Science and Conservation Division, and Coast and Marine Conservation branches of S.A. Department for Environment and Heritage (DEH); Marine and Coastal Community Network of S.A. (MCCN), and Threatened Species Network (TSN). Web version published by Reef Watch, South Australia.

---

Western Fortescue

Family Name:	Tetrarogidae
Scientific Name:	Centropogon latifrons Mees, 1962
Recommended Status in S.A:	Data Deficient
Rationale:  The Western Fortescue is included here because (i) it has a limited known distribution in South Australia, and is more common in south-western Australia; (ii) it is a benthic species associated with shallow marine seagrass beds, and may thus be vulnerable to population decline due to habitat impacts in some coastal areas; (iii) the species is part of the bycatch in trawl / net fisheries, but bycatch data are lacking; and (iii) benthic fishes in general have limited mobility, and often localised reproduction, which are vulnerable population characteristics. Very little is known of the distribution or relative abundance of this species in South Australia, which is at the edge of the range.

Page Contents

Current Conservation Status

no listings known

Distribution

Southern Australia

The Western Fortescue occurs mainly in W.A., from the Great Australian Bight through to Kalbarri; however it has also been recorded in parts of South Australia, such as Kangaroo Island (Hutchins and Swainston, 1986; 2001; Australian Museum, 2006a).
The holotype is from Cheyne Bay in W.A. (WAM specimen 5140.001, cited in OZCAM database, 2007).
There are very few museum records of this species (W.A. Museum, 2003; OZCAM database, 2005-2007).

South Australia

Apart from Kangaroo island being part of the distribution (see above), little else of the distribution of C. latifrons within S.A. has been recorded.

Habitat

C. latifrons is found in coastal seagrass beds (Hutchins and Swainston, 1986, 2001; Poss, in Gomon et al., 1994).
In parts of W.A., C. latifrons has also been recorded in sandy surf zones (Ayvazian and Hyndes, 1995) and other sandy habitats (e.g. Hyndes et al., 1999).

Notes on the Biology and Behaviour

Growth

C. latifrons grows to around 11cm (Hutchins and Thompson, 1983; Hutchins and Swainston, 1986, 2001) or 12.5cm (Poss, in Gomon et al., 1994).

Diet

The Western Fortescue belongs to a family of bottom-dwelling fishes that are predators of crustaceans and small fishes (Nelson, 1994, cited in Froese and Pauly, 2006). The related species C. australis (from south-eastern Australia) eats mainly crustaceans found in seagrass beds (Bell et al., 1978), and amongst small patch reefs and rocky rubble (G. Edgar, University of Tasmania, pers. comm., 2006).

Fisheries Information

The species is not targeted, but is a minor component of the bycatch in some southern Australian fisheries. Wayte et al. (2004) reported that “Centropogon australis latifrons” is a minor bycatch species otter in the South East Trawl Fishery (SETF). In the otter trawl sub-fishery of the SETF, an Integrated Scientific Monitoring Program (ISMP) reported that in 8 trawl shots, about 21kg were discarded (Wayte et al., 2004).
In W.A., the species is caught infrequently in nets, in coastal seagrass beds (Hutchins and Thompson, 1983, 2001); however no data are available for this report.  It is noted that the related species in eastern Australia is caught in estuaries in New South Wales (Gray and Kennelly, 2001), where it is a significant component of the discarded bycatch in coastal prawn trawl (up to 30% frequency of capture) and fish trawl fisheries (e.g. N.S.W. Department of Primary Industries, 2004).
The species is used in the international aquarium market. In 2005, Centropogon latifrons specimens for export were selling for US$18 - $25 per fish, depending on size (Ryan and Clarke, 2005).

Vulnerable Characteristics of the Species

The Western Fortescue has a limited known distribution in South Australia, and is more common in south-western Australia.
The Western Fortescue is a benthic species associated with shallow marine seagrass beds, and may thus be vulnerable to population decline due to habitat impacts in some coastal areas.
Benthic fishes in general have limited mobility and localised reproduction, which are vulnerable population characteristics.

Threatening Processes

There is very little information about the capture of this species. Given its distribution and habitat, it might be part of the bycatch in the prawn trawl fishery on the west coast of South Australia (for which bycatch data are not collected), and possibly also in Investigator Strait. The Western Fortescue is captured in low numbers in Commonwealth-managed fisheries that operate at the edge of the range, such as the SETF. A draft ecological risk assessment report for the South East Trawl Fishery, listed C. latifrons as being a “medium risk” species, in terms of population impacts from trawling (Wayte et al. 2004). It is noted that trawling is considered to be a threatening process for the related eastern Australian species in New South Wales (C. australis), which is ranked as having a high “fisheries impact profile” and as being at high risk of population impacts from trawling (N.S.W. Department of Primary Industries, 2004).
There are no data on population sizes, or on the numbers taken for the aquarium market, or the locations from which they are taken, and therefore no assessment of the sustainability of this practice. It is noted that the species is not included in the list of species taken in the W.A. Aquarium Fishery (Department of Fisheries, Western Australia, 2004b).

Research Requirements

More information is required on the distribution and relative abundance across the range, and also the biology and population dynamics of this species.
The bycatch of Western Fortescue in trawls and other net fisheries should be documented over its range, to determine whether a risk assessment is necessary.

Management Requirements

Ongoing efforts are required to reduce the bycatch of benthic fish such as Western Fortescue in trawl / net fisheries in S.A. and southern W.A.
Where Western Fortescue is taken for the aquarium industry, the numbers and locations should be documented over space and time, and an assessment of the populations and the sustainability of this practice should be undertaken.

Other Information

The Western Fortescue is reported to be less common than the Eastern Fortescue C. australis, which occurs in similar habitat, in south-eastern Australia (Edgar, 2000).