I & I NSW Wild Fisheries research Program Blue ( australasicus)

Exploitation Status Moderately Fished

Overall the stock off NSW is believed to be moderately fished, but there may be localised depletions.

Scientific name Standard name comment Scomber australasicus blue mackerel Also known as slimy mackerel

Scomber australasicus Image © Bernard Yau

Background

Blue mackerel (Scomber australasicus) occur in Relatively young (less than 2 years old) blue sub-tropical and temperate waters of the Pacific mackerel are caught by the Ocean Hauling and Indian Oceans. Blue mackerel occur off all Fishery in purse seine nets. Smaller quantities states of Australia except the NT. The species are also taken in bait nets (which are modified inhabits inshore and continental shelf waters, hauling nets) and general purpose hauling nets. with older fish occurring further offshore. Similar catch levels occur in all months of the In the last decade there has been considerable year. research into the biology and stock assessment Commercial landings of blue mackerel since the of blue mackerel. Blue mackerel grow relatively mid 1980s have generally been between 300 quickly, reaching approximately 17-22 cm and 500 tonnes annually but show considerable fork length (FL) after one year. They reach a fluctuations. These fluctuations are likely to maximum age of about 7 years and length of reflect changes in stock availability due to 50 cm. Blue mackerel mature at about recruitment variability and may also reflect 24-28 cm FL and spawning takes place during changes in the distribution of fish due to late winter and spring in outer continental oceanographic processes. shelf waters off northern NSW and southern QLD. Off NSW the oldest fish occur offshore, beyond state waters, and are targeted by Commonwealth licensed purse seine and mid- water trawl fishers. In 2008/09 Commonwealth fishers landed about 2,000 tonnes of blue mackerel.

status of fisheries resources in nsw, 2008/09 Blue mackerel | p 35 wild fisheries research program

Additional Notes Landings by Commercial Fishery of Blue Mackerel • South Australian Research and Development Ocean Trap and Line Institute have provided a biomass estimate Ocean Hauling (Target Species) based on a daily egg-production model of

25,000-33,000 t off the east coast of Australia. 600 (Ward and Rogers, 2007). 500 • The minimum recreational catch off NSW is 400 likely to be in the order of 90 t, while annual 300

commercial landings off NSW have recently Landings (t)

been around 500 t. Additional quantities are 200 utilised by both recreational and commercial fishers as ‘bait for own use’. 100 0

• Commonwealth assessments do not consider 97/98 99/00 01/02 03/04 05/06 07/08

the species to be overfished nor subject to Financial Year overfishing (Wilsonet al. 2009). Reported landings of blue mackerel by NSW commercial fisheries from 1997/98. Fisheries which contribute less • There is a recreational bag limit of 50 blue than 2.5% of the landings are excluded for clarity and mackerel. privacy. • Considerable quantities also taken for bait by fishers (under permit).

Growth Curve of Blue Mackerel Catch Recreational Catch of Blue Mackerel 35 The annual recreational harvest of blue mackerel in NSW is likely to lie between 90 30 and 200 t. This estimate is based upon the results of the offsite National Recreational and

Indigenous Fishing Survey (Henry and Lyle, 25 FL (cm) 2003) and onsite surveys undertaken by I & I NSW. 20 15 Historical Landings of Blue Mackerel 0 2 4 6 8 10 Age (years)

600 Growth curve for blue mackerel (Ward and Rogers, 2007). Lengths are presented as fork length (FL). 400 Landings (t) 200 0

58/59 68/69 78/79 88/89 98/99 08/09 Financial Year Commercial landings (including available historical records) of blue mackerel for NSW from 1955/56 to 2008/09 for all fishing methods. Landings were low until the commencement of purse seining in the 1980s.

p 36 | Blue mackerel status of fisheries resources in nsw, 2008/09

Length Frequency of Blue Mackerel Further Reading Glaister, J.P. and J.H. Diplock (1993). Baitfish and 1995/96−2001/02 the east coast tuna and billfish fishery: Species, 0.20 n = 12 176 status and situation. East Coast Tuna Management Advisory Committee. Canberra, Australian Fisheries

0.15 Management Authority: 114 pp. Henry, G.W. and J.M. Lyle (2003). The National 0.10

Proportion Recreational and Indigenous Fishing Survey. Final Report to the Fisheries Research & Development

0.05 Corporation and the Fisheries Action Program Project FRDC 1999/158. NSW Fisheries Final Report

0.00 Series No. 48. 188 pp. Cronulla, NSW Fisheries. 10 15 20 25 30 35 40 Lowry, M., A. Steffe and D. Williams (2006). Relationships between bait collection, bait type and catch: A comparison of the NSW trailer-boat and 2003/04−2006/07 gamefish-tournament fisheries.Fisheries Research

0.20 n = 6441 78 (2-3): 266-275.

0.15 Manning, M.J., J.A. Devine, P.M. Marriot and P.R. Taylor (2007). The length and age composition of the commercial catch of blue mackerel (Scomber 0.10

Proportion australasicus) in EMA 1 & 7 during the 2004-05 fishing year. New Zealand Fisheries Assessment 0.05 Report 2007/35. ISSN 1175-1884. Neira, F.J. and J.P. Keane (2008). Ichthyoplankton-based 0.00 spawning dynamics of blue mackerel (Scomber 10 15 20 25 30 35 40 australasicus) in south-eastern Australia: links to the East Australian Current. Fisheries Oceanography 17 (4): 281-298. 2007/08

0.20 n = 1286 Rogers, P.J., T.M. Ward, L.J. McLeay, M. Lowry, R.J. Saunders and D. Williams (2009). Reproductive

0.15 biology of blue mackerel, Scomber australasicus, off southern and eastern Australia: suitability of the

0.10 Daily Egg Production Method for stock assessment. Proportion Marine and Freshwater Research 60 (2): 187-202.

0.05 Stewart, J. and D.J. Ferrell (2001). Age, growth, and commercial landings of yellowtail scad (

0.00 novaezelandiae) and blue mackerel (Scomber

10 15 20 25 30 35 40 australasicus) off the coast of New South Wales, Australia, New Zealand Journal of Marine and FL (cm) Freshwater Research 35 (3): 541-551. The length distribution of blue mackerel landed by NSW Stewart, J., D.J. Ferrell and N.L. Andrew (1998). commercial purse seine fishers is comprised mainly of Ageing Yellowtail (Trachurus novaezelandiae) and fish between 25 and 35 cm FL and has remained relatively Blue Mackeral (Scomber australasicus) in New stable in recent years. There is no minimum legal length South Wales. Final report to Fisheries Research for blue mackerel in NSW. and Development Corporation - Project 95/151. Cronulla, NSW Fisheries. Stewart, J., D.J. Ferrell and N.L. Andrew (1999). Validation of the formation and appearance of annual marks in the otoliths of yellowtail (Trachurus novaezelandiae) and blue mackerel (Scomber australasicus) in New South Wales. Marine and Freshwater Research 50 (5): 389-395. Ward, P., T. Timmiss and B. Wise (2001). A review of biology and fisheries for mackerel. Report to the Fisheries Resources Research Fund, Bureau of Rural Sciences Australia: 104 pp.

Blue mackerel | p 37 wild fisheries research program

Ward, T. and P.J. Rogers (Eds.) (2007). Development and evaluation of egg-based stock assessment methods for blue mackerel, Scomber australasicus, in southern Australia. Final Report, Fisheries Research & Development Corporation. Project 2002/061. Adelaide, South Australian Research and Development Institute. 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.

Please visit the CSIRO website, http://www.marine.csiro.au/caab/ and search for the species code (CAAB) 37 441001, common name or scientific name to find further information.

© State of New South Wales through Industry and Investment NSW 2010. You may copy, distribute and otherwise freely deal with this publication for any purpose, provided that you attribute Industry and Investment NSW as the owner.

Disclaimer: The information contained in this publication is based on knowledge and understanding at the time of writing (April 2010). However, because of advances in knowledge, users are reminded of the need to ensure that information upon which they rely is up to date and to check currency of the information with the appropriate officer of Industry and Investment NSW or the user’s independent adviser.

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