© 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.

---

Spiny Gurnard / Southern Spiny Gurnard

Family Name:	Triglidae
Scientific Name:	Lepidotrigla papilio (Cuvier, 1829)
Recommended Status in S.A:	Data Deficient, possibly Near Threatened
Rationale:  Although it has a broad distribution across southern Australia, Spiny Gurnard is included here because (i) it is a site-associated benthic species from upper- and mid-continental shelf waters, in sand / rubble habitats, and thus may be vulnerable to site-specific impacts in some areas (ii); it is vulnerable to capture in a number of fish and prawn trawl fisheries; (iii) prawn trawlers operate in most of the areas in S.A. where this species has been found (e.g. central GSV, Investigator Strait, Spencer Gulf and the eastern GAB), and it is one of the most frequently caught bycatch species in the Spencer Gulf prawn fishery; (iv) risk assessments in trawl fisheries indicate that it has a low resilience, and low probability of survival when caught, and populations are considered to be at medium to high risk of impact in various trawl fisheries across the range; (v) in S.A., there is inadequate information about the bycatch of this species, other than in Spencer Gulf; and (vi) data on relative abundance over the range are inadequate, and there is little information on the biology (including longevity, reproduction, recruitment strength etc), population dynamics and ecology of this species.

Page Contents

Current Conservation Status

no listings known

Distribution

Southern Australia

The Spiny Gurnard is found across southern Australia, from northern N.S.W. through to W.A., and including Tasmania (Hutchins and Swainston, 1986).

South Australia

Examples of locations in S.A where the species has been recorded include the Great Australian Bight; southern Eyre Peninsula; northern, central and southern Spencer Gulf; Investigator Strait / north-eastern Kangaroo Island; south-western Gulf St Vincent / “heel” of Yorke Peninsula; metropolitan Gulf St Vincent and the Fleurieu Peninsula (Carrick, 1997; Reynolds, 2000; J. Lewis, photograph, 2005; South Australian Museum records, Museum of Victoria records, cited in OZCAM database, 2007; CSIRO data, cited in CSIRO, 2007).

Habitat

Spiny Gurnard occurs in shallow coastal bays, to around 60m deep (Gomon, in Gomon et al., 1994). The species is found mostly in sand and rubble areas in estuaries, and on sand near coastal reefs (Hutchins and Swainston, 1986; Australian Museum, 2005h).
In southern W.A., L. papilio was recorded during a study (1991-1993) of the fish faunas over predominantly sandy substrates in waters 5-35 m depth (Hyndes et al. 1999).
In parts of Tasmania, juveniles of L. papilio have been recorded in low numbers in Heterozostera tasmanica seagrass beds, and also in un-vegetated mud habitat (Jordan et al., 1998).

Notes on the Biology

Growth

L. papilio grows to around 18cm – 20cm (Hutchins and Swainston, 1986; Neira et al., 1998; Australian Museum, 2005h).

Diet

Platell and Potter (1999) recorded amphipods and mysids in the diet of L. papilio.

Reproduction

Lepidotrigla species have buoyant, pelagic eggs (Neira et al., 1998).

Other Information

Like other gurnards, this species can “walk” along the sea floor using the feelers in front of the enlarged pectoral fins (Hutchins and Swainston, 1986).

Fisheries Information

Commercial - Commonwealth Fisheries

Spiny Gurnard is part of the bycatch in the Commonwealth-managed Southern and Eastern Scalefish and Shark Fisheries (SESSF) (AFMA, 2002a). In the otter trawl sub-fishery of the South East Trawl Fishery (SETF), an Integrated Scientific Monitoring Program (ISMP) reported that in 3 trawl shots, about 51kg of L. papilio were retained and none was discarded (Wayte et al., 2004), which averages 17kg per trawl shot.
Bromhead and Bolton (2005) and Daley et al. (2006) reported L. papilio to be a retained by-product in the Great Australian Bight Trawl Fishery; however, it is noted that the species was not recorded in the bycatch during an Integrated Scientific Monitoring Program between 2001 and 2004 (Brown and Knuckey, 2002; Daley et al., 2006).

Commercial - State Fisheries

In New South Wales, L. papilio is a significant part of the bycatch in the Wreck Bay and Tathra inshore grounds of the ocean fish trawl fishery, with a frequency of occurrence of 54% across all trawls (N.S.W. Department of Primary Industries, 2004). It is also a significant part of the bycatch in the ocean prawn trawl (shelf sector) in New South Wales, with a frequency of occurrence of 21% across all trawls sampled (N.S.W. Department of Primary Industries, 2004).
L. papilio is a minor discarded bycatch species in the Bass Strait Central Zone Scallop Fishery (Bromhead and Bolton, 2005). For example, 4 specimens were recorded in 35 random tows, during a bycatch study in 2001 (Haddon and Semmens, 2001), and 25 were recorded in 59 random tows in 2002 (Haddon and Semmens, 2002).
According to McLeay et al. (2002), L. papilio is also part of the mixed catch of gurnard species taken by commercial fishers in Tasmania. Red Gurnard (Chelidonichthys kumu) and Latchet (Pterygotrigla polyommata) have separate catch statistics (see synopses), but catches of all other gurnards are aggregated into the category “Gurnard”, which would include L. papilio and others. Between 1990 and 2000, the reported catch of “Gurnard” species combined has ranged between 2.7t (in 1998/99) and 18.6t (in 1990/91), with less than 10t per annum taken in each year between 1995 and 2000 (Lyle and Hodgson, 2001).
According to data by Carrick (1997), Spiny Gurnard 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, 737 specimens of L. papilio were caught during 32 trawl tows in Spencer Gulf, comprising almost 1% of the total catch by numbers (including prawns). Svane (2005) reported that L. papilio comprises 3% of all the discarded bycatch species in the Spencer Gulf prawn trawl fishery.

Recreational

Spiny Gurnard is also caught by fishers in some areas (e.g. Gulf St Vincent) (Edgar, 2000).
Gurnards in general are taken by some recreational fishers in southern Australia, including South Australia (see statistics from Henry and Lyle, 2003, cited above); however species-specific information is not available.

Vulnerable Characteristics of the Species, and Threatening Processes

Compared with some of the other gurnard species, L. papilio may have a relatively narrow depth range, in upper- and mid-continental shelf waters. Site-associated benthic fish species such as gurnards may be susceptible to localised impacts in some areas where benthic habitats are degraded (e.g. parts of Spencer Gulf and Gulf St Vincent), but there are no data.
In South Australia, the species occurs in relatively shallow sand habitats in Gulf St Vincent, Investigator Strait, Spencer Gulf, and along the eastern Great Australian Bight, and prawn trawlers operate in all of these areas. Due to its benthic existence and preference for sandy habitat, the Spiny Gurnard is susceptible to capture in prawn trawl fisheries and fish trawlers on the continental shelf.
In 2006, an Ecological Risk Assessment for species in the Great Australian Bight Trawl Fishery (Daley et al., 2006), ranked L. papilio as a “medium risk” species, in terms of population impacts from capture in the GAB Trawl Fishery. It is noted that in a draft ecological risk assessment of the South East Trawl and Danish Seine Fishery (SETF) (Wayte et al., 2004), 4 “productivity attributes” and 5 “attributes of susceptibility” for L. papilio were used to categorise it as a “low risk” species in terms of susceptibility to population impacts from trawling in that fishery, likely due to the fact that this species is normally found in waters shallower than those trawled in the SETF.
L. papilio 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 barotrauma when hauled in trawls; has “low to moderate resilience”, and a low probability of survival when caught, and L. papilio was classified overall as a “high risk” species in terms of population impacts from trawl fishing (NSW Department of Primary Industries, 2004).

Research Requirements

There is little information on the distribution and relative abundance over the range, and on the biology, population dynamics and ecology of this species.
In S.A., the presence of this species in the West Coast Prawn Fishery and the Gulf St Vincent Prawn Fishery should be ascertained, because it occurs in the areas trawled by those fisheries, but bycatch data are not usually recorded. In all fisheries where this species is taken in more than incidental quantities, bycatch should be reported and monitored. In S.A., a system should be developed for the ongoing collection and monitoring of bycatch data from the Gulf St Vincent Prawn Fishery and the West Coast Prawn Fishery (as currently occurs in the Spencer Gulf Prawn Trawl Fishery), sufficient to enable identification of long-term trends in bycatch (Australian Government DEH, 2004b).
More generally, bycatch of gurnard species in all coastal fisheries should be recorded at species level, over space and time. Ideally, long term monitoring of the quantities of gurnard species in the bycatch of trawl fisheries should be undertaken before and after the adoption of gear improvements to reduce bycatch, and in “control” (non-trawled) areas.

Management Requirements

In south-eastern and southern Australia, methods are required to reduce the bycatch of this species in fish trawl and prawn trawl fisheries over the continental shelf, in both State and Commonwealth waters.
Although measures have already been undertaken in S.A. prawn trawl fisheries to reduce the bycatch of benthic fish species (see Management Notes, below), further improvements (e.g. in net design) should be encouraged, to reduce the bycatch of site-associated benthic species such as Spiny Gurnard.
Recreational catch limits should be introduced for gurnard species.

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 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; S.A. Prawn Industry Association web site, 2000; PIRSA 2003). In New South Wales prawn fishery, recent 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).