SUMMARY

SUMMARY

IDENTIFICATION

SCIENTIFIC NAME(s)

Trachurus declivis

SPECIES NAME(s)

Greenback horse mackerel, Jack mackerel

COMMON NAMES

Common jack mackerel , Cowanyoung

Greenback horse mackerel (Trachurus declivis) are an important commercial species with the main fishing grounds off the west coast of the North of New Zealand. Caught commercially with trawls, purse seines, traps and on line gear. The common jack mackerel or cowanyoung is found in coastal waters of southern Australia from Wide Bay, Queensland to Shark Bay, WA, including Tasmania (Wilson et al. 2009). 

There are three jack mackerel subpopulations in Australian waters: one in the Great Australian Bight, another in NSW waters, and the third off Tasmania. They are pelagic, forming schools over the continental shelf and outer shelf margin. Individuals have been found in depths of 460 m but this species is more commonly found between 20 m and 300 m (Wilson et al. 2009).

There is evidence of at least two biological stocks of Common Jack Mackerel in Australian waters: one off eastern mainland Australia, including eastern Tasmania, and the other extending from western Tasmania through to southern Western Australia. A separate biological stock also exists in New Zealand waters. These conclusions are based on morphological and meristic differences between fish from the Great Australian Bight and eastern Australia, genetic differences between fish from the Great Australian Bight and New Zealand, and a lack of genetic difference between fish from eastern Tasmania and New South Wales. While not conclusive, the above evidence was considered sufficient for the Common Jack Mackerel in the Small Pelagic Fishery (Commonwealth) to be managed as separate eastern and western biological stocks (Moore and Mazur 2016).

The bulk of the catch is caught by purse-seine (Ocean Hauling fishery) with small quantities landed by trawlers; most is sold for aquaculture feed or bait. This species was the subject of a large fishery off Tasmania in the 1980s, but recent catches have been very small. A lack of assessment data has led to the status of the jack mackerel stock being classified as ‘uncertain’ (Moore and Mazur 2016).


ANALYSIS

No related analysis

FISHSOURCE SCORES

Management Quality:

Management Strategy:

NOT YET SCORED

Managers Compliance:

NOT YET SCORED

Fishers Compliance:

NOT YET SCORED

Stock Health:

Current
Health:

NOT YET SCORED

Future Health:

NOT YET SCORED


RECOMMENDATIONS

RETAILERS & SUPPLY CHAIN
  • This profile is not currently high on our priority list for development, and we can’t at this time provide an accurate prediction of when it will be developed. To speed up an evaluation of the sustainability status of lower priority fisheries we have initiated a program whereby industry can directly contract SFP-approved analysts to develop a FishSource profile on a fishery. More information on this External Contributor Program is available at https://www.sustainablefish.org/Programs/Science/External-Contributor-Program.

FIPS

No related FIPs

CERTIFICATIONS

  • Australian small pelagic fishery:

    Withdrawn

Fisheries

Within FishSource, the term "fishery" is used to indicate each unique combination of a flag country with a fishing gear, operating within a particular management unit, upon a resource. That resource may have a known biological stock structure and/or may be assessed at another level for practical or jurisdictional reasons. A fishery is the finest scale of resolution captured in FishSource profiles, as it is generally the scale at which sustainability can most fairly and practically be evaluated.

ASSESSMENT UNIT MANAGEMENT UNIT FLAG COUNTRY FISHING GEAR
Western Australia Commonwealth Trawl Sector Australia Single boat bottom otter trawls
Great Australian Bight Trawl Australia Single boat bottom otter trawls
Scalefish Fishery (TAS) Australia Midwater trawls
Small Pelagic Fishery Australia Purse seines

Analysis

OVERVIEW

RECOMMENDATIONS

Last updated on 15 January 2019

Recommendations to Retailers & Supply Chain
  • This profile is not currently high on our priority list for development, and we can’t at this time provide an accurate prediction of when it will be developed. To speed up an evaluation of the sustainability status of lower priority fisheries we have initiated a program whereby industry can directly contract SFP-approved analysts to develop a FishSource profile on a fishery. More information on this External Contributor Program is available at https://www.sustainablefish.org/Programs/Science/External-Contributor-Program.

1.STOCK STATUS

STOCK ASSESSMENT

Last updated on 24 October 2016

No DEPM survey or estimate of spawning biomass has been conducted for jack mackerel (west) (Ward and Grammer 2016).

SCIENTIFIC ADVICE

Last updated on 24 October 2016

There is a paucity of information on life history and productivity for jack mackerel (west). Data from jack mackerel (east) were used instead, which may compromise the model outputs for the stock (Ward and Grammer 2016).

Reference Points

Last updated on 24 Oct 2016

These models suggest that the current harvest strategy is appropriate, and its application would result in a low probability of the stock falling below 0.2B0 for more than 90 per cent of the time, in line with the HSP (Ward and Grammer 2016).

CURRENT STATUS

Last updated on 24 October 2016

The peak total catch in 2006–07 was less than 1 per cent of the 1970s biomass estimate and 7 per cent of the RBC. There was no reported catch for 2014–15. Catch in 2015–16 increased to 631 t, which is 17 per cent of the RBC and TAC (Moore et al. 2010; Moore and Mazur 2016).

Catches in recent years have been low; the current catch is close to zero. The above evidence indicates that the stock is unlikely to be recruitment overfished and that the current level of fishing pressure is unlikely to cause the stock to become recruitment overfished. On the basis of the evidence provided above, the biological stock is classified as a sustainable stock (Ward and Grammer 2016).

The peak harvest from this fishery was less than 1 per cent of the spawning biomass estimate, and catches have been low as a proportion of estimated biomass. Although this biomass estimate is quite dated, this level of fishing mortality is unlikely to have substantially reduced spawning biomass. As a result, jack mackerel (west) is classified as not overfished for both years assessed. Current fishing mortality remains a small proportion of biomass, and below the 2014–15 and 2015–16 RBCs. The stock is therefore classified as not subject to overfishing for both years assessed (Ward and Grammer 2016).

Trends

Last updated on 24 Oct 2016

No daily egg production method survey or estimate of spawning biomass has been conducted for the western Common Jack Mackerel stock. Aerial surveys in the 1970s suggested a biomass off western Tasmania of at least 80 000 t. Catches peaked in 2006–07, when they were less than 1 per cent of the biomass estimate and 9 per cent of the current TAC (5000 t) for the Small Pelagic Fishery (Commonwealth) (Moore et al. 2010; Moore and Mazur 2016). 

Total catch (state and Commonwealth) for jack mackerel (west) did not exceed 250 t before 2005–06. Commonwealth catch was zero or negligible from 2011–12 to 2014–15, and increased to 631 t in 2015–16. State catches have been negligible for the past decade (Moore et al. 2010; Moore and Mazur 2016).

2.MANAGEMENT QUALITY

No related analysis

3.ENVIRONMENT AND BIODIVERSITY

BYCATCH
ETP Species

Last updated on 24 October 2016

Studies in the Northern Hemisphere have shown that, although interactions with dolphins (Bottlenose and Common dolphins occur in Australia) can be common, these species are rarely caught by purse seine and, when caught, usually survive. Mortalities of both seals and dolphins have been recorded during midwater trawl operations in this fishery. Dolphin encounters appear to be very rare; however, underwater cameras have revealed that seals commonly enter and forage in midwater trawl gear, with some mortalities. Seal excluder devices in the trawl nets have had some success in reducing, but not eliminating, lethal interactions (Pikitch et al. 2012).

Common Jack Mackerel play a role in the pelagic food chain as a link between primary and secondary producers and top predators, including tunas, sharks, marine mammals and seabirds. Recognising this important ecological role, the harvest strategy adopted in the Small Pelagic Fishery (Commonwealth) restricts catches to conservative levels of below 20 per cent of current spawning biomass estimates. These are consistent with levels internationally recommended for the sustainable management of forage fisheries (Pikitch et al. 2012).

HABITAT

Last updated on 24 October 2016

Of the three main fishing methods used to target Common Jack Mackerel (purse seine, midwater trawl and beach seine), only beach seine interacts with the benthos. Studies in New South Wales have shown that purse-seine nets have a negligible impact on seagrass habitats. Both purse-seine and midwater trawl fisheries interact with marine mammals, including seals and dolphins. Purse-seine nets remain open to the surface (Pikitch et al. 2012). 

FishSource Scores

SELECT SCORES

MANAGEMENT QUALITY

STOCK HEALTH:

No data available
No data available
No data available
No data available
No data available
No data available
No data available
No data available
No data available
No data available
No data available
No data available

No related analysis

Fishery Improvement Projects (FIPs)

No related FIPs

Certifications

Marine Stewardship Council (MSC)

SELECT MSC

NAME

Australian small pelagic fishery

STATUS

Withdrawn

SCORES

The Australian Small Pelagic fishery has voluntarily withdrawn from the Marine Stewardship Council certification process. The withdrawal is effective as of 19th May 2016.

Certification Type:

Sources

Credits
  1. Moore, A., Hobsbawn, P., Summerson, R., Skirtun, M., 2010. 7 Small Pelagic Fishery, Fishery status reports 2010, 99-113http://data.daff.gov.au/data/warehouse/fishstatus20109abff00101/fishstatus20109abff00101_11a/07_FishStatus2010SmallPelagic_1.00.pdf

  2. Wilson, D., R. Curtotti, G. Begg and K. Phillips, Eds. (2009). Fishery Status Reports 2008: status of fish stocks and fisheries managed by the Australian Government. Canberra, Bureau of Rural Sciences & Australian Bureau of Agricultural and Resource Economics.

  3. Moore, A.  and Mazur K., 2016. Chapter 7 Small Pelagic Fishery, Fishery status reports 2016. http://apo.org.au/files/Resource/00_fishstatus2016_1.0.0_lr.pd

  4. Ward TM, Grammer, G, Ivey, A, Carroll, J, Keane, J, Stewart, J & Litherland, L 2015, Egg distribution, reproductive parameters and spawning biomass of blue mackerel, Australian sardine and tailor off the east coast during late winter and early spring, FRDC project 2014/033, FRDC & SARDI, West Beach.

  5. Ward, TM & Grammer, G 2016, Commonwealth Small Pelagic Fishery: fishery assessment report 2015, report to AFMA, SARDI publication F2010/000270-7, Research Report Series 900, SARDI Aquatic Sciences, Adelaide.

  6. Pikitch, E, Boersma, PD, Boyd, IL, Conover, DO, Cury, P, Essington, T, Heppell, SS, Houde, ED, Mangel, M, Pauly, D, Plagányi, É, Sainsbury, K & Steneck, RS 2012, Little fish, big impact: managing a crucial link in ocean food webs, Lenfest Ocean Program, Washington, DC, www.oceanconservationscience.org/foragefish/.

References

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    Greenback horse mackerel - Western Australia

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