Balmain Bugs

Fishery Overview

The Ocean Trawl Fishery can be divided into two sectors, the Ocean Fish Trawl and the Ocean Prawn Trawl Fisheries. Although the two forms of trawling target different species and are different in operation, they take many common species and have a significant level of geographic overlap (NSW DPI, 2007). The non-selective nature of trawl nets, and the broad range of substrates over which trawling occurs, results in a large number of finfish and shellfish species being taken. The major species targeted by ocean prawn trawlers vary with the depth of fishing, and include Eastern King Prawn, Eastern School Prawns and Royal Red prawns, and Eastern School Whiting. Fish trawling mainly targets species such as Silver Trevally, Tiger Flathead, Southern Calamari, Eastern School Whiting and a number of shark and ray species (NSW DPI, 2007).

The prawn sector can be divided further into three sub-fisheries:

• Inshore prawn trawl, which uses otter trawl gear to target prawns within 3nm of the coast;
• Offshore prawn trawl, which uses otter trawl gear to target prawns from waters outside 3 nautical miles and west of the 280 metre (150 fathom) depth contour; and
• Deepwater prawn trawl, which uses otter trawl gear to target prawns east of the 280 metre (150 fathom) depth contour.

The inshore and offshore sectors generally target Eastern King Prawns, with the offshore sector operating out to the edge of the continental shelf (approximately 230 m).  The deepwater prawn sector targets species of deepwater prawns, such as Royal Red Prawns, at depths in excess of 310 m (Macbeth et al. 2008).

The fish trawl sector can also be further divided into two sub-fisheries:

• The Fish (northern zone) fishery, is authorised to take fish using an otter trawl net (fish) or a Danish seine trawl net (fish) from ocean waters north of Barrenjoey Headland (latitude 33°35′ south).
• The Southern Fish Trawl sector is authorised to take fish (other than prawns) using an otter trawl net (fish) or a Danish seine trawl net (fish) from ocean waters inside 3 nautical miles and south of Barrenjoey Headland.

Trawlers off NSW catch four of the eight known species of Ibacus, collectively marketed as ‘Balmain Bugs’. The most commonly caught NSW species are the ‘true’ eastern Balmain Bug (Ibacus peronii) and the Smooth Bug (I. chacei), which both grow in size to 8-9 cm carapace length (CL) and weigh between 300 and 400 g (Macbeth et al. 2008). Honey Bug (I. brucei) which mainly inhabits outer continental shelf and upper slope depths (120-300 m) off northern NSW and Queensland is caught in lower numbers, in addition to a forth species, the Deepwater Bug (I. alticrenatus), which occurs mainly at depths of 200 to 400 m (Stewart and Zeller, 2016).  Honey Bug
is occasionally targeted by prawn trawlers off the NSW north coast and small quantities of Deepwater Bugs are caught by trawlers targeting fish or prawns on the upper continental slope.  Commercial catch statistics do not differentiate between the four species, but 90% of the catch taken while vessels are targeting Eastern King Prawn is Smooth Bug (Haddy et al., 2007).  In 2015, 19t of Balmain Bugs were harvested in the OTF compared to 66t in the Queensland East Coast Otter Trawl Fishery (ECOTF) (Stewart and Zeller, 2016).

Figure 1 Catch trends

Risk Scores

Summary of main issues

• There are no well-defined harvest control rules in the fishery which would serve to reduce exploitation as the point of recruitment impairment is approached;
• The information available on discard and ETP species interactions in the fishery is relatively limited and there has been no ongoing independent, spatially representative monitoring of the fishery;
• The information base to support assessments of habitat impacts from the fishery is limited compared to other trawl fisheries in Australia and internationally. Detailed mapping and habitat classification of the NSW continental shelf has recently been undertaken, though there appears to be only limited information on the fine scale spatial distribution of effort in the fishery, particularly overlayed against potentially vulnerable habitat types.

Outlook

1A: Stock Status

CRITERIA: (i)The stock is at a level which maintains high productivity and has a low probability of recruitment overfishing.

The common name ‘Balmain Bug’ refers to four similar species of fan lobster: Ibacus alticrenatus, I. brucei, I. chacei and I. peroni (Stewart and Zeller, 2016). These species partially overlap in their distributions on the east coast of Australia and have evolved different life-history strategies, tending to occupy different depth ranges. However, here, they are assessed as a single species group because they are rarely distinguished by fishers or fish marketers.

Given the prevailing influence of the East Australian Current along the east coast out to 150 m depth, a protracted pelagic larval phase and a northerly migration of older stages, true Balmain Bugs, Smooth Bugs and Honey Bugs are thought to each constitute single biological stocks across Queensland and New South Wales (Stewart and Zeller, 2016). Stock status of the Balmain Bugs species group in these jurisdictions is therefore presented at the biological stock level—East Coast biological stock.

Catch in the Queensland portion of the fishery comprises almost exclusively Smooth Bugs (I. chacei) (Stewart, 2015).

Stewart and Zeller (2016) report that:

• “in New South Wales, Balmain Bugs (primarily true Balmain Bugs and Smooth Bugs) are trawl target species and have been assessed in terms of their commercial nominal catch rates and length compositions in landings. Median catch rates (kg per day in the ocean prawn trawl fishery) have fluctuated throughout the past 20 years but have shown no overall trends. The size compositions in landings have remained stable for both species. The above evidence indicates that the biomass of this part of the stock is unlikely to be recruitment overfished”;
• “in Queensland, fishers harvest Balmain Bugs as a byproduct of Eastern King Prawn fishing. Logbook data indicates that Balmain Bugs contribute only a very minor component of the Eastern King Prawn fishers’ catch and landed value. Balmain Bugs fishing mortality is managed by a prohibition on landing of egg-bearing females; conservative minimum legal sizes (MLS), which were updated in 2009; and mandatory use of turtle excluder devices since the early 2000s, which have been shown to lower the incidental catch rates of scyllarid lobsters, including Balmain Bugs. In addition, the spawning stock is partly protected from fishing during an annual seasonal closure. Landings have declined over the past decade from an average of 93 t per year in 2006–10 to 79 t per year in 2011–15. While nominal catch rates have declined since 2011 and the 2015 catch was relatively low (66 t), this is considered to be a result of the increased MLS for I. chacei and fisher behaviour, and not declining abundance.

A recent risk assessment of the Queensland East Coast Otter Trawl Fishery found a low risk of recruitment overfishing on the Queensland part of the East Coast Balmain Bug stock at the 2009 effort level south of the Great Barrier Reef Marine Park^5,6, where about 83 per cent of the catch is taken. Fishing effort targeting Eastern King Prawn in Queensland has declined by eight per cent since 2009, further reducing the risk of overfishing. The risk of recruitment overfishing within the Great Barrier Reef Marine Park (GBRMP) was assessed to be intermediate to high⁷. However, fishing effort in the GBRMP has declined by 24 per cent since 2009, further reducing risk for this part of the stock.

The above evidence indicates that the biomass of the Queensland part of the stock is unlikely to be recruitment overfished…”

While the available evidence suggests it is likely the stock is above the point of recruitment impairment (PRI), there is little evidence to indicate the stock is at or fluctuating around a level consistent with MSY.  It is not clear to what extent declining nominal catch rates and catch indicate reduced fishing mortality, reduced availability or reduced abundance. Accordingly, we have scored this stock medium risk.

1B: Harvest Strategy

CRITERIA:  (i)There is a robust and precautionary harvest strategy in place.

In addition to the management strategy above for Eastern King Prawn, Balmain Bugs have several specific harvest restrictions:

• Ban on the retention of females in berry in NSW and Queensland.
• Minimum size limits – 100 mm carapace width in NSW, based on the average size of female maturity for Balmain Bugs and Smooth Bugs (Stewart, 2015).
• NSW recreational possession limit of 20 per person.
• Queensland recreational size limit of 10.5 cm carapace width.

The harvest strategy in both the OTF and ECOTF is not likely to be responsive to the state of the stock given the lack of prescriptive harvest reduction processes (e.g. harvest control rules) outlined in any management response. There is significant latent effort in both fisheries and if it was activated it is unclear how the fisheries managers would respond. However, the strategy is expected to achieve the management objectives in Criterion 1A(i) based on the fact there is relatively frequent monitoring of commercial catch and effort trends that are expected to be sensitive enough to detect if the stock is approaching PRI, and that some form of harvest reduction would then be implemented by fisheries managers.

NA – this SI is only scored if the target species is a shark.

CRITERIA: (ii) There are well defined and effective harvest control rules (HCRs) and tools in place

There are currently no well-defined HCRs in the OTF harvest strategy which require a reduction in exploitation as the PRI is approached. There are some ‘in house’ trigger points used in the annual stock assessment workshops such as presence of a certain number of age classes indicating health of spawning stock or an approximation of recruitment, but these are not publicly available.  The FMS and SMP set out a framework of trigger points against prescribed goals and performance indicators, but action to review exploitation of primary species is triggered only after a species is declared ‘overfished’ or ‘recruitment overfished’, rather than before the stock reaches PRI.  Stock status is assessed periodically according to the Framework for the Assessment of Harvested Fish Resources in NSW (Scandol, 2004).

In the ECOTF, there are currently no well-defined HCRs which set out pre-agreed measures to limit exploitation as the PRI is approached.  The best approximation of a HCR in the fishery was the Performance Management System (PMS) which established trigger points, which if breached, triggered a review of available data and management arrangements if required (QG, 2009). Nevertheless, use of the PMS has been largely discontinued, with the most recent report available from 2012 (DEEDI, 2012).  There is also evidence from other key target stocks within the ECOTF that existing arrangements have not served to reduce exploitation as the PRI is approached (e.g. saucer scallops; Kangas and Zeller, 2016).  Accordingly, it not clear that generally understood HCRs are in place that are expected to reduce exploitation as PRI is approached.

Notwithstanding that, stock monitoring in recent years has detected no evidence of recruitment overfishing for either Eastern King Prawns or Balmain Bugs and effort levels are at very low levels historically. Moreover, the Queensland Government has recently committed to the development of a harvest strategy with well-defined HCRs for the ECOTF by the end of 2018 (DAF, 2017b). Accordingly, in the absence of existing HCRs, we have scored this SI precautionary high risk.

1C: Information and Assessment

CRITERIA: (i) Relevant information is collected to support the harvest strategy.

The harvest strategy for Balmain Bugs is primarily based on the application of a conservative MLS which allows a sufficient proportion of females to breed prior to entry into the fishery.  The reproductive biology of both main species, Eastern Balmain Bugs and Smooth Bugs, is sufficiently well-known to establish an evidence-based MLS (Stewart et al, 1997; Haddy et al, 2005; 2007).  Although the biology of the deeper water species (I. brucei, I. alticrenatus) is less well understood, some information is available on the distribution and stock structure of the two main species to support the harvest strategy (e.g. Haddy et al, 2007).

Fleet composition is well understood and data are collected to support the harvest strategy including vessel details, VMS data (ECOTF), trawl effort (hours and distribution), and vessel power of the fleet.  Catches are typically reported by fishers as a ‘Balmain Bug’ species group, which may mask changes in species composition, although port sampling is undertaken in NSW to determine catch composition and monitor length frequency (Stewart, 2015).   While some information exists to support a harvest strategy, the extent to which existing information base could support an HCR that served to reduce exploitation as the PRI is approached for each species is uncertain.  Accordingly, we have scored this SI medium risk.

Removals from the Balmain Bug stock are exclusively by the commercial sector and monitored through compulsory catch and effort logbooks.  In the ECOTF, the main indices of abundance are catch and nominal catch rate which are not always a reliable index of abundance (e.g. Harley et al, 2001).  In the OTF, stock status is monitored through nominal catch rate as well as commercial size composition (Stewart and Zeller, 2016).   However, indicators are not monitored consistent with a formal HCR. Given stock removals and at least one indicator are monitored we have scored the stock medium risk.

CRITERIA: (ii) There is an adequate assessment of the stock status.

No formal assessment has been undertaken of the East coast Balmain Bug stock.  The stock is currently assessed periodically using a ‘weight-of-evidence’ approach based on available indicators including nominal commercial catch rates, levels of overall effort and commercial size composition data from NSW (e.g. Stewart and Zeller, 2016).  The assessment assesses status relative to generic reference points by way of status categories (e.g. overfished, sustainable, transitional-recovering, etc). Accordingly, we have scored the stock medium risk.  The stock would be better positioned against this indicator with a more formal, quantitative assessment.

Balmain Bug

The ‘weight-of-evidence’ approach used for the Balmain Bug stock relies on the qualitative judgement of scientists familiar with the stock to account for uncertainty, but there is no quantitative accounting for uncertainty.  Assessment outcomes published through the Status of Key Australian Fish Stocks website are peer-reviewed.

2A: Other Species

CRITERIA: (i) The UoA aims to maintain other species above the point where recruitment would be impaired (PRI) and does not hinder recovery of other species if they are below the PRI.

The intent of this scoring issue is to examine the impact of the fishery on ‘main’ other species taken while harvesting the target species.  ‘Main’ is defined as any species which comprises >5% of the total catch (retained species + discards) by weight in the UoA, or >2% if it is a ‘less resilient’ species.  The aim is to maintain other species above the point where recruitment would be impaired and ensure that, for species below PRI, there are effective measures in place to ensure the fishery does not hinder recovery and rebuilding.

The OTF Prawn Fishery encompasses multiple bioregions, gear types and target grounds. As a result, the composition of other species taken in the fishery varies both spatially and temporally (e.g. Macbeth et al, 2008). Previous studies have shown that the fishery interacts with a very large number of species, most of which occur only very infrequently in trawls (e.g. Kennelly et al, 1998; Macbeth et al, 2008).  The OTF FMS lists other main species as: Eastern School Prawn, Royal Red Prawn, Octopus, Cuttlefish (Sepia spp.), Southern Calamari, Tiger Flathead, Sand Flathead, Silver Trevally and Fiddler Shark. However, the last five species are probably more targeted by the OTF Fish Trawl Fishery.

There are few recent published estimates of the species composition of discards for the various sectors of the OTF, so two different information sources have been used to identify main other species taken in the fishery:

• Catch data for retained species reported in logbooks between 2010-11 and 2014-15; and
• Species compositions reported from onboard observer studies (e.g. Kennelly et al, 1998; Macbeth, 2008).

Eastern King Prawn and Eastern School Whiting have been assessed under Component 1 in the full assessment report. Only Eastern School Prawn (12%) comprised >5% of the retained catch in the Inshore and Offshore Prawn sectors combined during the period 2010-11 to 2014-15.  Of the remaining species, Stout Whiting accounted for 3.5% of the retained catch and a group of undifferentiated ‘trawl octopus’ accounted for 6.7% although is likely to be made up of multiple species. Based on this, Eastern School Prawn is assessed here as a main other species based on reported catch data.

Kennelly et al (1998) examined catch composition of the prawn sector in the OTF across four main ports in northern NSW in a two-year observer-based study.  They found significant variations in species-specific abundances at all spatial and temporal scales sampled, such that the occurrences and abundances of particular bycatch species depended on the location, season and year examined. In catching an estimated 1,579t of prawns during the two-year survey, oceanic prawn trawlers from the four ports were estimated to have caught approx. 16,435t of bycatch (a bycatch-to-prawn ratio of 10.4:1). Of this bycatch, 2,952t were estimated to have been retained for sale and 13,458t were discarded.  Although catch by weight was not reported, the only individual non-prawn species accounting for >5% of the total catch by number (retained + discarded) were stout whiting and Eastern School Whiting (albeit called Red Spot Whiting in the study).  The cuttlefish and octopus groups also accounted for >5% of the catch by number, although may have comprised multiple species.

More recently, Macbeth et al (2008) examined the impact of square mesh cod ends on catch composition in the northern part of the OTF in paired comparisons against standard diamond mesh cod ends.  While the data in this report is based on catch rate by number of fish rather than weight, there appeared to be no very large discrepancies between the average weights among individual species. Apart from Eastern King Prawns and Eastern School Whiting, other species accounting for >5% of the catch in this study were Eye Gurnard (Lepidotrigla argus) and Longspine Flathead (Platycephalus longispinus). All other species accounted for <5% of the total catch by weight.

On the basis of the two observer studies, we have also assessed here as main other species Stout Whiting, Eye Gurnard and Longspine Flathead, albeit we note that recent evidence of full catch composition in the OTF is limited.

For Eastern School Prawn, Taylor et al (2016) report that the NSW stock of Eastern School Prawn is unlikely to be recruitment overfished.  They note that fluctuations in stock abundance appear to be environmentally-driven, rather than driven by the fishery itself, with recent research establishing that environmental factors can have a strong influence on Eastern School Prawn catches.  Accordingly, the stock is likely to be above the PRI.

For Stout Whiting, Roy and Hall (2016) report that population modelling conducted in 2014 indicated that biomass was marginally above the biomass that would produce MSY. Accordingly, the stock is highly likely to be above the PRI.

No assessments have been conducted for either Eye Gurnard or Longspine Flathead.  Fishbase lists Eye Gurnard as having high resilience with low to moderate vulnerability (Froese and Pauly, 2017).    Longspine Flathead is reported as having medium resilience and low to moderate vulnerability.  While the status of each species against the PRI is not known, given the relatively productive nature of both species, there is a plausible argument that the measures in place (e.g. vessel/gear limits, BRDs, spatial closures) are at least likely to ensure the fishery does not hinder recovery or rebuilding if necessary. Accordingly, we have scored this SI medium risk.

Nevertheless, we note the fishery would be better placed against this SI with a more recent estimate of catch and discards composition by weight based on information directly from the fishery, and assessments of likely impact on key non-target species.  NSW DPI (2017a) report that observer field work in the fish trawl sector of the OTF has been completed with a final report due in December 2017.  In the prawn trawl sector, observer field work commenced in June 2017 incorporating the 2017/18 and 2018/19 fishing seasons.

CRITERIA: (ii) there is a strategy in place that is designed to maintain or to not hinder rebuilding of other species.

The OTF manages bycatch and byproduct harvest through limiting effort, gear design (e.g. minimum mesh size, including allowances for smaller square mesh cod ends; mandatory bycatch reduction devices), actively trying to reduce effort through the SMP as well as a series of closures (summarised in NSW DPI, 2011).  Specific management interventions have been introduced for species of concern (e.g. Gulper Shark[1]; Mulloway[2]).

The FMS also has a specific PI with a trigger for the development of a recovery plan if any byproduct species is assessed as overfished (e.g. Mulloway recovery plan).  The FMS also includes triggers for management action if there is a significant change in species composition of catch and if discards in the fishery increases substantially between consecutive observer surveys (NSW DPI, 2007). While these measures are intended to maintain main other species at levels above the PRI, limited and sporadic monitoring of other species catch composition and discard rates means it is difficult for the management agency to assess trends and therefore to have confidence that other species are highly likely to be above PRI.  Accordingly, we have scored the fishery medium risk against this SI.

[1] http://www.dpi.nsw.gov.au/fishing/commercial/fisheries/ocean-trawl/gulper-shark

[2] http://www.dpi.nsw.gov.au/fishing/commercial/fisheries/ocean-trawl/managing-the-otf-impact-on-mulloway

Given the healthy stock status of Eastern School Prawns and Stout Whiting, the relatively productive nature of the other two main other species and observer studies documenting reductions in bycatch through BRDs (e.g. Macbeth et al, 2008), there is a plausible argument that the existing measures are likely to be limiting fishing mortality on other species to levels likely to be above the PRI.  Nevertheless, we note that there is minimal objective evidence that the strategy is working, and no recent independent evidence that it is being implemented successfully.

NA

CRITERIA: (iii) Information on the nature and amount of other species taken is adequate to determine the risk posed by the UoA and the effectiveness of the strategy to manage other species.

Some quantitative information is available for retained non-target species through commercial logbooks, and for total catch composition (by number) through targeted, occasional research studies (e.g. Kennelly et al, 1998, Macbeth et al, 2008).  There is no ongoing monitoring of non-retained species composition and volume. The available information is adequate to broadly identify the likely main other species in the fishery and estimate the impact of the fishery, but is not sufficient to assess the impact of the fishery with respect to status of main other species or to detect increased risk to them.

2B: Endangered Threatened and/or Protected (ETP) Species

CRITERIA: (i) The UoA meets national and international requirements for protection of ETP species.
The UoA does not hinder recovery of ETP species.

The OTF Environmental Impact Statement (EIS) found all threatened and protected fish species to be at low or moderately low risk from the operation of the OTF (NSW DPI, 2004). The risk of the OTF impeding the conservation and recovery of threatened marine mammals and reptiles was assessed as low or moderately low, and that for threatened seabirds moderately low (NSW DPI, 2011).

No ETP interactions have been reported in commercial logbooks for the OTF since reporting was made mandatory in 2005. With the current gear used in the prawn otter trawl nets, an onboard observer based study observed very few ETP interactions (Macbeth et al. 2008). These included infrequent interactions with certain species of syngnathid; Hippocampus tristis, Solegnathus lettiensis and Solegnathus spinosissimus (20 individuals in total) and one Sandtiger Shark (Odontaspis ferox) caught over four trips. All of these individuals were returned to the water alive. Nevertheless, it is worth noting the study had relatively limited spatial and temporal coverage and relatively high levels of observer coverage are required to reliably estimate occurrence of infrequent events.

Gulper sharks have also been taken in the deeper areas of the OTF, although are unlikely to be incidentally taken in the fishery for the target species assessed here.

While qualitative information suggests that the impact of the fishery on ETP species is low, and that the fishery is therefore unlikely to be hindering recovery of ETP species, independent evidence (e.g. observer coverage) is very limited so it cannot be concluded with confidence that the fishery is highly unlikely to be hindering recovery of ETP species. Accordingly, we have scored this SI medium risk.

CRITERIA: (ii) The UoA has in place precautionary management strategies designed to:

• meet national and international requirements; and
• ensure the UoA does not hinder recovery of ETP species.

Under the FM Act the take of ETP species by commercial fishers is prohibited.  The main measures in place which serve to limit interactions with ETP species include:

• limiting effort;
• gear design, including the use of bycatch reduction devices[1]; and
• a series of closures including a habitat closure including all reef habitat in the fishery, 18 area closures mainly situated around nearshore geographical features and overfished species (Dogfish, Mulloway and Gemfish) closures in habitat areas important for their life history or known aggregation sites.

The FMS also has a specific PI with a trigger for management action if there are any observations by commercial fishers or observers that are likely to threaten the survival of ETP species.  Nevertheless, observer coverage has been low to non-existent and it is not clear whether other mechanisms have been used to monitor the ETP-related trigger points.

While the available evidence suggests interactions with ETP species are low and the existing measures are expected to ensure the fishery does not hinder recovery, the absence of ongoing validation of interactions means the information required to monitor performance against indicators remains relatively limited.  Accordingly, we have scored this SI medium risk.

[1] http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0004/352237/bycatch-closure.pdf

The OTF EIS found that all threatened and protected fish species to be at low or moderately low risk from the operation of the OTF. The risk of the OTF impeding the conservation and recovery of threatened marine mammals and reptiles was assessed as low or moderately low, and that for threatened seabirds moderately low (NSW DPI, 2011).

Available onboard observer coverage indicates that interactions with ETP species are limited, and many captured ETP species (e.g. syngnathids) can be released alive (e.g. Macbeth, 2008).  Accordingly, the measures in place are likely to work based on plausible argument.  However, the absence of ongoing independent monitoring in the fishery to estimate levels of interaction and verify logbook reports of ETP interactions, limits the objective basis for confidence to conclude the measures are working.

CRITERIA: (iii) Relevant information is collected to support the management of UoA impacts on ETP species, including:

• information for the development of the management strategy;
• information to assess the effectiveness of the management strategy; and
• information to determine the outcome status of ETP species.

The level of ETP interaction in the OTF is monitored through mandatory reporting in commercial logbooks for the OTF. However there has been very little independent monitoring of ETP interactions to verify the accuracy of logbooks reporting.  The main study conducted (Macbeth et al, 2008) suggests some degree of non-reporting.  Accordingly, while some quantitative information is available through compulsory logbook reports and isolated bycatch studies, confidence that these provide an up to date representation of current interactions with ETP species in the fishery is not strong.  To that end, we have scored this SI medium risk.

2C: Habitats

CRITERIA: (i) The UoA does not cause serious or irreversible harm to habitat structure and function, considered on the basis of the area(s) covered by the governance body(s) responsible for fisheries management

Australian seabed habitat has been classified using the Integrated Marine and Coastal Regionalisation of Australia Version 4.0 (IMCRA) (DEH, 2006) (Figure 2). The IMCRA is an ecosystem-based classification of Australia’s marine and coastal environments that was developed through the collaborative efforts of State, Territory and Commonwealth marine management and research agencies.  Trawling for Eastern King Prawns is concentrated mainly off the north coast of NSW, with the majority of fishing occurring north of Newcastle in depths from 20 to 200m. Trawling targeted at Eastern School Whiting occurs year round on sandy bottoms in depths of 20 to 80m, mainly north of Sydney (DPI NSW, 2004).  The majority of the Eastern King Prawn grounds occur within the Central Eastern Shelf Transition (CEST) bioregion categorised under the IMCRA.  Trawling for Eastern King Prawn and Eastern School Whiting also occurs in the Central East Shelf Province (CESP).

Sediments in the CEST bioregion are relatively homogenous, dominated by sand with localised gravel deposits and negligible mud. Sand is the dominant sediment type associated with the geomorphic features found in this provincial bioregion including shelf, slope and shallow water terraces (DEWHA, 2009). Shallow water terraces in this provincial bioregion also contain a significant proportion of gravel. The absence of reefs was noted by Keene et al (2008) who characterised the Central Eastern Shelf Transition region as having <0.01% reef.  In the CESP, sediment texture is dominated by sand with localised deposits of gravel in the north of the provincial bioregion. Observer studies have indicated that prawn trawling only occurs on sandy/muddy bottom (e.g. Macbeth et al. 2008).

Figure 3: Map of the East Marine Region depicting Provincial Bioregions (IMCRA v4.0) (from DEWHA, 2007)

The OTF EIS concluded that the otter-trawl gear used in the fishery had a high risk of causing enduring harm to the function and structure of biota associated with hard substratum, including biogenic habitat.  Additionally, the OTF was rated as having a high risk of impacting biota associated with soft seabed habitat. The process used to identify risks to habitats and risk assessment outcomes were described in Astles et al (2009).

Since the EIS was written there have been a series of closures implemented in the fishery which protect all hard substratum as well as a substantial area of the fishery[1].  In addition, a number of new marine parks have been declared in NSW waters since 2005 (e.g. Cape Byron Marine Park, Port Stephens-Great Lakes Marine Park and the Batemans Marine Park) and large areas within these marine parks have been closed to trawling. Likewise, other management actions have been taken including prohibiting the use of bobbins on ground ropes of fish trawl nets north of Seal Rocks, and limiting the maximum size for bobbins on fish trawl nets south of Seal Rocks (NSW DPI, 2008). Work has also reportedly been done to map commercial trawling grounds out to 100 fathoms between the Queensland border and Coffs Harbour (NSW DPI, 2011), although no publicly available information on this has been found.

We have scored this SI medium risk on the basis that the evidence suggests the majority of available trawl ground is likely to be dominated by sandy habitat with little reef structure, trawlers are likely to actively avoid 3-dimensionally structured habitats and existing reef structures have received protection under law.  Nevertheless, the publicly available evidence to assess the impact of the OTF on habitats is substantially weaker than comparative fisheries elsewhere in Australia (e.g. Queensland East Coast Otter Trawl Fishery; Commonwealth trawl fisheries) and the fishery would be better positioned against this SI with additional analysis to demonstrate either that risks were minor or that moderate or high risks have been dealt with to the extent that the fishery is not likely to reduce habitat structure and function of the point of serious or irreversible harm.

This is particularly the case for biota associated with soft seabed habitats for which levels of protection may not match those for reef areas.  We note that considerable seabed mapping work (e.g. Davies et al. 2007, 2008a & b; Jordan et al, 2009) has been undertaken since the adoption of the FMS, and logbook reporting requirements have reportedly been refined to allow for a finer scale understanding of the spatial distribution of trawl effort.  Further analyses of these data in support of achieving the FMS aim of estimating “a series of closures to trawling to protect a representative range of ocean habitats and their associated biota, in addition to those that are already protected within the boundaries of Marine Parks or permanent trawl closures” should be prepared for use in future assessments.

[1] http://www.dpi.nsw.gov.au/fisheries/info/closures/commercial/ot

CRITERIA: (ii) There is a strategy in place that is designed to ensure the UoA does not pose a risk of serious or irreversible harm to the habitats.

The main management measures in place which serve to limit habitat interactions in the OTF include limited entry, limits on vessel and gear size, as well as a series of closures including:

• A closure including all reef habitat in the fishery
• 18 area closures mainly situated around nearshore geographical features
• Overfished species (Dogfish, Mulloway and Gemfish) closures in habitat areas important for their life history or known aggregation sites

In addition, six multiple use marine parks covering around one third (approximately 345,000 hectares) of the NSW marine estate have been declared which include large areas closed to trawling[1].

The FMS “aims to establish a series of closures to trawling to protect a representative range of ocean habitats and their associated biota, in addition to those that are already protected within the boundaries of Marine Parks or permanent trawl closures. Included in this approach will be the closure of areas with ‘hard’ bottom habitats, which are at risk of being permanently modified by the effects of trawling. In the longer term, closures to trawling may be implemented to provide ‘refuge’ areas for species targeted by trawling as scientific information becomes available – these areas could include specific closures to protect habitats considered to be critical to the survival of any life-history stage of species taken by trawling.” The FMS also has a specific PI with a trigger for management action if there are any observations by commercial fishers or observers that are likely to threaten the survival of key habitats.

While information on the spatial footprint of fishing effort in the context of habitats within the fishery is currently limited, the available evidence suggest that fishing takes place over unconsolidated soft sediments (e.g. Macbeth et al, 2008), and there are measures in place which could be expected to ensure the fishery limits impact to areas of higher three dimensional structure (e.g. reef closures).  In addition, marine parks have been established in inshore areas to protect representative samples of marine biodiversity.  Accordingly, the measures in place which could be expected to ensure the fishery does not reduce the structure and function of habitats to the point of serious or irreversible harm and we have scored this SI medium risk.  Nevertheless, the absence of quantitative analysis of the impacts of otter trawling and Danish seining on habitats types in the fishery mean that there is limited evidence upon which to support an effective strategy.

[1] http://www.dpi.nsw.gov.au/fishing/marine-protected-areas/marine-parks

There is a plausible argument that the management strategy is likely to work based on the fact that limited onboard observer coverage indicates that fishing occurs almost entirely over muddy/sandy bottom, and that there are large areas of sensitive habitat closed to the OTF.  Prawns predominantly occur over soft seabed and prawn trawling cannot be successfully conducted over hard substratum due to gear loss. Nevertheless, there is very limited evidence to provide any objective level of confidence.

CRITERIA: (iii) Information is adequate to determine the risk posed to the habitat by the UoA and the effectiveness of the strategy to manage impacts on the habitat.

The types and distribution of the main habitats have been well documented for the deeper shelf waters of the fishery (Bax & Williams 2001, Williams and Bax. 2001, Williams et al. 2009) and a major mapping program has provided information on the major habitat types and their location within NSW waters (Davies et al. 2007, 2008a & b, Jordan et al. 2009). The vulnerability of these habitats has been identified in the OTF EIS as well as the Commonwealth Trawl Fishery ERA.  The main weakness appears to be the lack of fine scale spatial data on the distribution of trawl effort, particularly in relation to its potential overlap with vulnerable habitat types.  We note that commercial logbooks have reportedly been redesigned to allow for finer scale spatial reporting which may help to address these weaknesses in future.

Information is adequate to broadly understand the nature of the main impacts of gear use on the main habitats, including spatial overlap of habitat with fishing gear at broad scales. The physical impacts of prawn trawling has been well studied in other jurisdictions (e.g. ECOTF), however, the level of habitat interaction in the OTF at fine spatial scales does not appear to be well-understood and observer coverage has been limited in the fishery.  Notwithstanding that, existing knowledge is probably sufficient to broadly understand the nature of the main impacts of gear use on the main habitats, and there is some information on the spatial overlap of habitats with fishing gear.  Accordingly, we have scored this SI medium risk.  Nevertheless, the fishery would be considerably better positioned against this indicator with additional analysis of finer scale spatial effort patterns overlayed against finer scale habitat distribution maps now available for the NSW continental shelf.

2D: Ecosystems

CRITERIA: (i) The UoA does not cause serious or irreversible harm to the key elements of ecosystem structure and function.

Serious or irreversible harm in the ecosystem context should be interpreted in relation to the capacity of the ecosystem to deliver ecosystem services (MSC, 2014). Examples include trophic cascades, severely truncated size composition of the ecological community, gross changes in species diversity of the ecological community, or changes in genetic diversity of species caused by selective fishing.

Prawn trawling in the OTF is relatively unselective so the fishery can impact the ecosystem through removals of target, byproduct and bycatch species as well as modification of seafloor habitats. In the original EIS for the fishery five shark species, five teleost species and two crustacean species were rated as being at high or moderately risk of being overfished, and 95% of the non-commercial bycatch species (fish and invertebrates) had a high or moderately high level of risk (NSW DPI, 2004). Some of the recommendations from the EIS to mitigate the impact of these species have been implemented, such as introduction of BRDs, reduction of total effort, introduction of a network of spatial and temporal closures and the implementation of square mesh codends for high ‘bycatch areas’.

Atlantis ecological modelling undertaken on the ecosystem of the eastern Australian Continental Shelf using data from large trawl surveys completed in 1976 and 1996 indicated that, while the OTF is fully exploited with most target species being at less than half their original biomass, diversity indices are not likely to have been significantly impacted in the area of the fishery (Savina et al. 2013).  The modelling predicted little change in detritus levels or in the lower trophic groups (e.g. plankton) in the 20 years to 1996, with the most significant changes in species groups that were under direct fishing pressure, where both the proportion of adults and total biomass typically decreased. Some non-harvested species, such as oceanic planktivores and mesopelagics, showed an increase in the proportion of adults, which was related to lower predation pressure from the heavily fished groups.

Notwithstanding information weaknesses around impacts on some ecosystem components (e.g. discards), the outcomes of the Atlantis modelling suggest the fishery is probably unlikely to disrupt the key elements underlying ecosystem structure and function to the point of serious or irreversible harm.

CRITERIA:  (ii) There are measures in place to ensure the UoA does not pose a risk of serious or irreversible harm to ecosystem structure and function.

The OTF FMS establishes the framework for the management of ecosystem impacts in the fishery, having as its first goal “management of the OTF in a manner that promotes the conservation of biological diversity in the marine environment” (NSW DPI, 2007).  Underneath this goal, a number of objectives are set out with the aim of minimising ecosystem impacts including mitigating the impact of trawling in NSW waters on ecosystem integrity, non-retained species and habitats. For each objective a series of proposed management measures are specified including defining and mapping trawl grounds, implementing a series of closures to trawling to protect the range of ocean habitats and associated biodiversity, promoting research and collaborate with research institutions to improve our understanding of ecosystem functioning and how it is affected by trawling designing and implementing an industry funded scientific observer program to document the degree of interaction with non-retained and threatened species.

The FMS also establishes a framework of performance indicators and trigger points to monitor the implementation of the strategy.

While the FMS framework itself could be considered at least a partial strategy to restrain ecosystem impacts so as to achieve the outcome in criterion 2D(i), the extent to which the management measures have been implemented and monitored appears variable.  While research on ecosystem impacts has been encouraged, limited progress appears to have been made on an observer program or habitat protection outside 3nm.  Notwithstanding that, the fishery does have measures in place (e.g. gear restrictions, closed areas, BRDs) which take into account the potential impacts of the fishery on the ecosystem.  Accordingly, we have scored this SI medium risk.

The outcomes of the Atlantis modelling provide at least some basis for confidence that the measures are working, although there is less evidence that all measures set out in the strategy have been implemented effectively (e.g. fishery observer program).  Accordingly, we have scored this SI medium risk.

CRITERIA: (iii) There is adequate knowledge of the impacts of the UoA on the ecosystem.

The key elements of the ecosystem where the OTF operates have been identified (e.g. NSW DPI, 2004, Fulton et al. 2011, Savina et al. 2013). However, given recent information on interactions with ecosystem components other than targeted species (e.g. discard volume and composition) is relatively limited, information is likely to be inadequate to detect increased risk to the ecosystem and trophic functioning.

The main interactions of the OTF on these key ecosystem components can be inferred from existing information on species removals and broad knowledge of the food webs in this environment.  While the impacts of removals by the OTF on the shelf ecosystem has been investigated using Atlantis modelling (Savina et al. 2013), data limitations around key ecosystem elements (e.g. discard composition and volume) mean that current impacts cannot be investigated in detail.

3A: Governance and Policy

CRITERIA: (i) The management system exists within an appropriate and effective legal and/or customary framework which ensures that it:

• Is capable of delivering sustainability in the UoA(s); and
• Observes the legal rights created explicitly or established by custom of people dependent on fishing for food or livelihood.

The OTF is managed under the Fishery Management Act 1994 (Act) and regulations made under this Act. NSW DPI is the State Government agency responsible for the administration of the Act.

The Act seeks to provide for ecologically sustainable development for the fisheries of NSW through the achievement of its stated objectives, which are to conserve, develop and share the fishery resources of the State for the benefit of present and future generations. The Act is aimed at achieving sustainable fisheries in accordance with Components 1 and 2.

In recognition of Aboriginal peoples’ cultural fishing needs and traditions, several significant Act amendments commenced in early 2010. They included:

• Extending the objectives of the Act to explicitly recognise the connection Aboriginal people have with the fisheries resource;
• The addition of a definition of Aboriginal Cultural Fishing to enable Aboriginal people to take fish or marine vegetation for cultural fishing purposes;
• The establishment of the Aboriginal Fishing Advisory Council (section 229) to ensure that Aboriginal people play a part in future management of the fisheries resource;
• Specific provisions under Section 37(c1) of the Act for issuing authorities for cultural events where fishing activities are not consistent with current regulation. This provision caters for larger cultural gatherings and ceremonies.
• Aboriginal persons being exempt from paying a recreational fishing fee under 34C of the Act.

In addition to the requirements of the Act, an Indigenous Fisheries Strategy and Implementation Plan (IFS) which was released in December 2002. The IFS put in place a process that will ensure discussion and negotiation to resolve problems and challenges in relation to Indigenous involvement in the fisheries of NSW.

CRITERIA: (ii) The management system has effective consultation processes that are open to interested and affected parties. The roles and responsibilities of organisations and individuals who are involved in the management process are clear and understood by all relevant parties.

The Organisations and individuals involved in the management process have been identified. Functions, roles and responsibilities are explicitly defined and well understood for key areas of responsibility and interaction. The Minister responsible for administering the Fishery Management Act 1994 is ultimately responsible for the management of NSW commercial fisheries.  The NSW DPI undertake day to day management of the EGF and act as a primary advisor to the Minister.  Other groups may also provide advice to the Minister or through the DPI, including the Ministerial Fisheries Advisory Council (MFAC), the Commercial Fishing NSW Advisory Council and the NSW Total Allowable Catch Setting and Review (TAC) Committee. For more information see:

http://www.dpi.nsw.gov.au/fisheries/commercial/consultation

Improved consultation arrangements were introduced in November 2012 following an Independent Review of NSW Commercial Fisheries Policy, Management and Administration. In addition to the Deputy Director General DPI Fisheries, who acts as the primary advisor to the Minister, key groups involved in the consultation process include:

• Ministerial Fisheries Advisory Council (MFAC) – established to provide cross-sectoral advice on strategic policy issues to the Minister for Primary Industries. It includes representatives from the commercial, recreational, indigenous, aquaculture and conservation sectors and has an independent Chair;
• Commercial Fishing NSW Advisory Council – the council is the key advisory body providing ongoing industry expert advice to Government on matters relevant to the sector. Membership covers each restricted and share managed fishery, as well as an aboriginal person who is a commercial fisher; and
• NSW Total Allowable Catch Setting and Review (TAC) Committee – The TAC Committee is a statutory body established under the provisions of the Fisheries Management Act 1994 (the Act).  It is required to determine and keep under review total allowable catch (or fishing effort) levels, as required. It gives effect to the objects of the Act having regard to all relevant scientific, industry, community, social and economic factors. Membership of the TAC Committee includes an independent Chairperson, a natural resource economist, a fisheries scientist and a person with appropriate fisheries management qualifications.

Task based and time-limited ad hoc working groups may also be formed on an as needs basis to provide expert advice on specific issues. Working group members are appointed by the Deputy Director General, DPI Fisheries based on skill and expertise relevant to the tasks assigned to the working group. Current working groups include a Baitfish Working Group and a NSW Lobster Industry Working Group.

Where substantive changes are proposed to management arrangements, public consultations occurs through the release of a Regulatory Impact Statement (RIS) which sets out the proposed changes, likely impacts and alternative options considered.

Accordingly, the management system has processes in place to regularly seek and accept information from interested parties.

For more information on the full process see: http://www.dpi.nsw.gov.au/fisheries/commercial/consultation

CRITERIA: (iii) The management policy has clear long-term objectives to guide decision making that are consistent with Components 1 and 2, and incorporates the precautionary approach.

The objectives of the Act include:

a) to conserve fish stocks and key fish habitats, and

b) to conserve threatened species, populations and ecological communities of fish and marine vegetation, and

c) to promote ecological sustainable development, including the conservation of biological diversity, and, consistently with those objectives:

d) to promote viable commercial fishing and aquaculture industries, and

e) to promote quality recreational fishing opportunities, and

f) to appropriately share fisheries resources between the users of those resources, and

g) to provide social and economic benefits for the wider community of New South Wales.

These objectives are consistent with Components 1 and 2.

3B: Fishery Specific Management System

CRITERIA:  (i) The fishery specific management system has clear, specific objectives designed to achieve the outcomes expressed by Components 1 and 2.

The OTF FMS has the following objectives for the fishery:

• Manage the OTF in a manner that promotes the conservation of biological diversity in the marine environment
• Maintain stocks of primary and key secondary species harvested by the OTF at sustainable levels
• Promote the conservation of threatened species, populations and ecological communities likely to be impacted by the operation of the OTF
• Appropriately share the resource and carry out fishing in a manner that minimises negative social impacts
• Promote a viable OTF, consistent with ecological sustainability
• Facilitate effective and efficient compliance, research and management of the OTF
• Improve knowledge about the OTF and the resources on which it relies

Additional fishery specific objectives and associated performance indicators and trigger points are set out in the Fisheries Management (Ocean Trawl Share Management Plan) Regulation 2006 (the ‘SMP’).

While these objectives are consistent with the outcomes expressed by Components 1 and 2, the main uncertainty is the extent to which the objectives as set out in the FMS and SMP actively guide management of the OTF given the age of the documents and the extent to which they have been superseded by other management initiatives (e.g. the BAP). Nevertheless, given that explicit objectives consistent with Components 1 and 2 exist within the management system we have scored this SI low risk.

CRITERIA: (ii) The fishery specific management system includes effective decision making processes that result in measures and strategies to achieve the objectives .

Under the NSW State Government’s fisheries decision-making process, the Fisheries Minister has ultimate responsibility for the management of the fishery and is empowered to make changes to the Fisheries Regulations and Management Plan. The Minister is advised by the NSW DPI and MFAC who, in turn, seek input from stakeholders and technical working groups.

The extent to which the management system could demonstrate that it has responded over time to all serious and other issues identified in relevant research, monitoring and evaluation in a timely, transparent and adaptive manner appears variable.  For example, for Eastern School Whiting unconstrained State catches and weaknesses in data collection have long had the potential to undermine the effectiveness of the overall harvest strategy, although concerted management action appears to have been taken in recent years.  A similar situation exists with the existence of substantial latent effort in the OTF, although action is now being taken through the BAP.

Nevertheless, there are examples in which the management system has responded to serious issues – for example, measures recover populations of dogfish and specific area closures implemented for the protection of critical habitats for grey nurse sharks.  Given that there is some evidence that the management system responds to serious issues we have scored this SI medium risk.

The use of the precautionary approach is required under the Act and is also addressed in Objective 1 in the FMS: To manage the OTF in a manner that promotes the conservation of biological diversity in the marine environment. Some examples of precautionary management in the fishery exist including prohibiting mid water trawls that target several overfished finfish species and the implementation of fishery closures on all reefs and in depths beyond 1100m. Nevertheless, there are management arrangements in place which appear to be less precautionary – for example, the existence of substantial excess harvesting capacity and limited understanding on catch composition and habitat impacts in some sectors.  Accordingly, the fishery does not appear to meet the low risk scoring guidepost.

Information on the fishery’s performance is available on the NSW DPI website, primarily through public reports of performance against the FMS trigger points (e.g. NSW DPI, 2016), stock status assessments (e.g. Stewart et al, 2015; NSW DPI, 2017b) and periodic reviews against the Guidelines for the Ecologically Sustainable Management of Fisheries by the Commonwealth environment department (e.g. NSW DPI, 2013).  Research reports relevant to the fishery are also available through the NSW DPI website (e.g. Macbeth et al, 2008) and websites of external funders (e.g. the Commonwealth Fisheries Research and Development Corporation).  The findings of relevant research are discussed through the consultative structure.  Where significant management changes are required, a RIS is released calling for public comment.  The RIS provides an explanation of the background to the proposed changes and alternative options considered.

CRITERIA: (iii) Monitoring, control and surveillance mechanisms ensure the management measures in the fishery are enforced and complied with.

The NSW fisheries compliance program is led by the NSW DPI Fisheries Compliance Unit (FCU), which is focused on optimising compliance with the Act, the Marine Estate Management Act 2014 and their associated regulations.  The FCU is separated into seven geographic compliance zones, with a State-wide Operations and Investigations Group that undertakes major/complex investigations, and the Conservation and Aquaculture Group that provides specialist capabilities in aquatic habitat compliance management.  NSW DPI Fisheries Compliance Plans are regularly reviewed for progress against the objectives of the Australian Fisheries National Compliance Strategy (AFNCS).

The MCS system in the OTLF primarily comprises commercial logbooks, at sea and land-based fisheries inspections of all sectors by the DPI Fisheries Officers and occasional observer coverage. Clear sanctions are set out in legislation enforceable through the courts with promotion of voluntary compliance through education. Additionally, there is a specific goal in the FMS to “facilitate effective and efficient compliance, research and management of the Offshore Trawl Fishery” with a trigger point to prompt a review if the percentage of inspections resulting in the detection of offences exceeds either of the following: 20% for minor offences and 10% for major offences.  This trigger point is assessed at least biennially and compliance statistics are reported annually on the DPI website.

Significant prosecutions and rates of compliance are publicly reported on the DPI website[1].  The compliance system appears to have an ability to enforce relevant management measures and rules.

[1] http://www.dpi.nsw.gov.au/fishing/compliance/fisheries-compliance-enforcement

Sanctions to deal with non-compliance are set out in the Act and the NSW Fisheries Compliance Enforcement Policy and Procedure document (NSW DPI, 2011).  Some evidence exists that fishers comply with the management system, including providing information of importance to the effective management of the fishery (e.g. catch and effort through logbooks). DPI (2017a) report that the annual rates of compliance in the OTF during the period 2012-13 to 2015-16 were:

• 2012/13 – 83.93%
• 2013/14 – 82.91%
• 2014/15 – 81.67%
• 2015/16 – 76.74%

The rate of compliance is calculated using information collected during fisher and fishing gear inspections and recorded in program activity reports that are completed by NSW DPI Fisheries Officers. The rates of compliance reported above are lower than might be expected in a high compliance fishery, and there is some evidence that interactions with ETP species may be under-reported (e.g. Macbeth et al, 2008).  Accordingly, we have scored this SI medium risk.

CRITERIA:  (iv) There is a system for monitoring and evaluating the performance of the fishery specific management system against its objectives.
There is effective and timely review of the fishery specific management system.

There are mechanisms in place to monitor performance of the management system against various trigger points in the FMS and SMP, as well as through annual stock status assessments.  The FMS and SMP set out operational objectives and performance indicators across the key elements of the management systems: target species, byproduct species, bycatch species, ecosystems and social indicators.  In addition, NSW DPI Fisheries Compliance Plans are regularly reviewed for progress against the objectives of the Australian Fisheries National Compliance Strategy (AFNCS).

The fishery is subject to occasional external review by the Commonwealth Department of the Environment against the requirements of the Environment Protection and Biodiversity Conservation Act 1999.  Generally, assessments have occurred every three years, with the current accreditation scheduled to expire in 2018.   The extent to which the fishery management system has been subject to regular internal review is somewhat unclear.  Performance against the FMS was to be subject to biennial review under the MAC. However, the plan for reviews under the new consultative structure is not available publicly.  Notwithstanding that, it is clear that at least occasional reviews of performance against the FMS have occurred (e.g. DPI, 2016).  Accordingly, we have scored this SI medium risk.

T​his seafood risk assessment procedure was originally developed for Coles Supermarkets Australia by MRAG Asia Pacific. FRDC is grateful for Coles’ permission to use its Responsibly Sourced Seafood Framework.

​It uses elements from the GSSI benchmarked MSC Fishery Standard version 2.0, but is neither a duplicate of it nor a substitute for it. The methodology used to apply the framework differs substantially from an MSC Certification.  Consequently, any claim about the rating of the fishery based on this assessment should not make any reference to the MSC.