© 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.

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Sand Dragonet / Spotted Dragonet / Spotted Stinkfish

Family Name:	Callionymidae
Scientific Name:	Repomucenus calcaratus (Macleay, 1881) = Callionymus calcaratus Macleay, 1881
Recommended Status in S.A:	Data Deficient
Rationale:  The Sand Dragonet is included here because (i) it is a site-associated benthic fish species in upper and mid continental shelf waters, and thus may be vulnerable to site-specific impacts in some areas, particularly shallow bays and estuaries; (ii) it is captured in large numbers in various trawl fisheries in south-eastern and southern Australia (including prawn trawling in S.A.), and a number of assessments have indicated that fishes in Callionymidae are susceptible to population impacts due to trawling; (iii) there is little information on the distribution and relative abundance of this species in South Australia; (iv) little is known of the biology (particularly longevity, and reproduction), ecology or population dynamics; and (v) there has been insufficient monitoring over space and time of the prawn trawl bycatch, and potential population impacts.

Page Contents

Current Conservation Status

No listings known

Distribution

Southern Australia

The Sand Dragonet ranges across southern Australia, however the distribution may encompass more than one closely related species (CSIRO, 2007). The eastern form ranges from southern Queensland to N.S.W. (including Norfolk I. and Lord Howe I. – Francis, 1993), and the western form (which may be a separate species) ranges from Kangaroo I.; through to the central coast of W.A. (Edgar, 2000; Australian Museum, 2005g).

South Australia

Most records in S.A. are from the gulfs region. Examples of locations where the species has been recorded include southern Eyre Peninsula / south-western Spencer Gulf; south-central Spencer Gulf, eastern Spencer Gulf, northern Spencer Gulf; southern Yorke Peninsula / south-western Gulf St Vincent (GSV); eastern (metropolitan) and south-eastern GSV, Investigator Strait and Kangaroo Island (MLSSA, 1997; Carrick, 1997; P. Jennings, SARDI, unpubl. data, 2003; South Australian Museum records, Museum of Victoria records, Australian Museum records, cited in OZCAM database, 2007).

Habitat

Sand Dragonet is found in sand habitat. The species is reported to be common near reef margins in shallow coastal bays in New South Wales; but often found in waters deeper than 20m in other parts of the range (Edgar, 2000).
R. calcaratus has also been recorded in shallow coastal estuaries (e.g. West and Jones, 1998, 1999, 2001; Resources Management Australia, 2000; Kennelly and McVea, 2002), including Zostera capricorni beds (Jelbart, 2004).
Published depth range is generally 5m - 100m (Edgar, 2000), but specimens from shallower waters have been collected (for example, 2m – 4m, in northern Spencer Gulf: Museum of Victoria record, 1997, cited in OZCAM database, 2007).

Notes on the Biology

Sand Dragonet grows to about 28cm (Australian Museum, 2005g).
Callionymids feed on small benthic invertebrates (Nelson, 1994, cited in Froese and Pauly, 2007).

Fisheries Information

Commercial – Commonwealth Fisheries

Sand Dragonet is a minor part of the discarded bycatch in the Commonwealth-managed South East Trawl Fishery (SETF). In the Danish seine sub-fishery of the SETF, an Integrated Scientific Monitoring Program (ISMP) reported that in 2 shots, about 4 kg of Common Stinkfish were discarded (Wayte et al., 2004).

Commercial – State Fisheries

The species is part of the discarded bycatch in the N.S.W. estuarine fish haul fishery (e.g. in Botany Bay) (Gray and Kennelly, 2001).
According to data by Carrick (1997), Sand Dragonet has been one of the top 10 bycatch species (by number) in the Spencer Gulf prawn trawl fishery in South Australia. For example, during a bycatch survey undertaken in the mid 1990’s, 1,364 specimens of R. calcaratus were caught during 32 trawl tows in Spencer Gulf, comprising almost 2% of the total catch by numbers (including prawns), and 6% of the fish bycatch. Museum of Victoria houses specimens from a number of areas in Spencer Gulf that are worked by the prawn trawl fleet (e.g. Plank Point, Western Shoal, The Gutter and Wallaroo).
The Sand Dragonet is part of the discarded bycatch in the Ocean Prawn Trawl and Ocean Fish Trawl fisheries in New South Wales. In the shelf sector of the Ocean Prawn Trawl fishery, fishery- independent surveys showed that the frequency of occurrence of C. calcaratus across all trawls was approximately 57% (N.S.W. Department of Primary Industries, 2004). In the Ocean Fish Trawl shelf sector (Wreck Bay and Tathra inshore grounds), the frequency of occurrence of this species in the bycatch was 30%.

Vulnerable Characteristics of the Species and Threatening Processes

The species is vulnerable to capture in trawl fisheries, which may be a significant source of mortality. A study of the susceptibility of trawl-caught fishes to population impacts (Stobutski et al., 2001) ranked fish bycatch species according to two overriding characteristics (based upon biological and ecological criteria): (i) the susceptibility to capture and mortality due to prawn trawling, and (ii) the population's capacity to recover after depletion. The rank of each species on these two characteristics determined its relative capacity to sustain trawling, and therefore its priority for research and management. Species that were the least likely to be sustainable included those in the Callionymidae. These species are highly susceptible to capture by trawls, they are benthic or demersal, their primary habitat is soft sediments, and their diet may include prawns. The recovery capacity of these species is also low, at the estimated removal rate by trawling (Stobutski et al., 2001).
The Sand Dragonet has been listed as one of the bycatch species in the N.S.W. Ocean Trawl Fishery that has a “high” fishery impact profile (New South Wales Department of Primary Industries, 2004). Studies in New South Wales showed that the species suffers trawl trauma when hauled in trawls, is moderately resilient, but has a low probability of survival when caught, and C. calcaratus was classified overall as a “high risk” species in terms of population impacts from trawl fishing (see N.S.W. Department of Primary Industries, 2004). Given that the species occurs in sand habitats in the gulfs region of S.A., and has been previously reported as one of the most common species in the fish bycatch in the Spencer Gulf prawn trawl fishery (Carrick, 1997), it is likely that populations of Sand Dragonet in S.A. would be similarly vulnerable to decline from the type of impacts specified for populations in N.S.W.
In some parts of the range, populations are associated with estuaries and other shallow nearshore habitats. Estuaries are often subject to many pollutants, and other impacts that degrade water quality and habitat. Polluted estuarine areas can take a long time to recover as toxicants accumulate in their sediments (Pogonoski et al., 2002). The fact that most population centres in Australia are located within close proximity to coastal and/or estuarine environments means that estuarine habitats and their associated communities are often vulnerable to the effects of habitat degradation, and overexploitation by humans (Pogonoski et al., 2002).

Research Requirements

Very little is known of the biology, ecology and population dynamics of this species.
There may be more than one species in Australia currently included in Repomucenus calcaratus, and more taxonomic work is required (CSIRO, 2007).
Long term monitoring of the quantities of this species in the bycatch of trawl fisheries is required, particularly before and after the adoption of gear improvements to reduce bycatch, and in “control” (non-trawled) areas.

Management Requirements

In prawn fisheries, adoption of gear designs that reduce the high levels of bycatch of sand-dwelling species such as Sand Dragonet should be encouraged (see below).

Management Notes

It is noted that prawn fisheries in southern Australia have made significant efforts during the past decades to reduce the bycatch of finfish species. Examples for Spencer Gulf and Gulf St Vincent include the spatial and temporal organisation and “real time” management of the fishing fleet in some areas (e.g. Spencer Gulf) to minimise capture of undersized prawns and bycatch species, and developments in gear design to reduce bycatch, such as square-mesh cod-ends, bycatch chutes, and the fitting of exclusion devices (e.g. MacDonald, 1998; Carrick, 1997; Broadhurst et al., 1999; South Australian Prawn Industry Association web site, 2000; PIRSA, 2003). In New South Wales prawn fishery, studies have investigated the effects of mesh size, shape, and increases to the lateral mesh openings in cod-ends. In two of the three types of seine used in that prawn fishery,  new designs made from 25- and 29-mm mesh hung on the bar (i.e. square-shaped mesh) significantly reduced the catches of non-target fish by between 58 and 95% (Macbeth et al., 2004, 2005; Broadhurst et al., 2004).