Transcript
I & I NSW
Wild Fisheries research Program
Spanish Mackerel (Scomberomorus commerson) Exploitation Status
Fully Fished
Majority of the commercial harvest occurs in Queensland waters and status from the Queensland assessment has been adopted. Scientific name
Standard name
comment
Scomberomorus commerson
Spanish mackerel
Scomberomorus commerson Image © Bernard Yau
Background Spanish mackerel are distributed in the waters of the Indo-Pacific from the Red Sea and South Africa to southeast Asia, north to China and Japan, and south to Australia. They are also found in the eastern Mediterranean Sea. In Australian waters, they are distributed from Geographe Bay in WA around northern and eastern Australia to St Helens in Tasmania. Within this geographical distribution, Spanish mackerel can be found from the edge of the continental shelf to shallow coastal waters. Adults are associated with coral reefs, rocky shoals and current lines on outer reef areas and offshore. Small juveniles up to 10 cm fork length (FL) occur in creeks, estuaries and sheltered mud flats during the early wet season in north Queensland. Sampling of Spanish mackerel in WA showed that 50% of females reached sexual maturity at about 79 cm, while 50% of males reached sexual maturity at 63 cm. Females can be categorised as serial or partial spawners with fish showing a peak in reproductive activity between August and January in WA, and during the spring/summer months in Queensland. They are highly fecund - large females produce
more than 1 million eggs. In Queensland waters, Spanish mackerel can reach 240 cm FL and a maximum weight of 70 kg with females growing to a larger size than males. Initial growth is rapid with fish reaching 100 cm in the first few years of life. The oldest males and females sampled from catches by the Queensland commercial fishery were 10 (127 cm FL, 19 kg) and 14 years (155 cm FL, 35 kg) respectively. Migrations of Spanish mackerel extend along the entire east coast of Queensland although permanently resident populations also seem to exist. Resident fish disperse from reefs after spawning whilst migrating fish can move up to 1000 nautical miles to the south (into NSW waters). The use of parasites to distinguish between stocks suggested that there may be six separate stocks of Spanish mackerel across northern Australia, however, the use of isozyme, allozyme and mitochondrial DNA genetic analysis failed to find any significant differences. The diet of Spanish mackerel consists of small fish like anchovies, clupeids and carangids, as well as squid and prawns.
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wild fisheries research program
Additional Notes • NSW commercial landings are small (< 10 t) compared with Queensland (200 - 600 t).
Landings by Commercial Fishery of Spanish Mackerel Ocean Trap and Line (Key Secondary Species)
• There are significant recreational landings of Spanish mackerel, especially in Queensland.
15
20
Ocean Hauling (Conditional Target Species)
0
5
• There is a minimum legal length of 75 cm total length for Spanish mackerel and a combined recreational bag limit of 5 for all Spanish and spotted mackerel.
10
Landings (t)
• A length-based stock assessment conducted in 2008 by Queensland Fisheries concluded that the stock was at about maximum sustainable yield level, with exploitable biomass estimated to be 35-60% of the unfished level.
*
97/98
99/00
01/02
03/04
05/06
07/08
Financial Year
Reported landings of Spanish mackerel by NSW commercial fisheries from 1997/98. * Fisheries which contribute less than 2.5% of the landings are excluded for clarity and privacy.
Recreational Catch of Spanish Mackerel
Catch Per Unit Effort Information of Spanish Mackerel Harvested by All Line Methods in NSW
0.6 0.0
30
98/99
20
Landings (t)
0.2
40
50
Historical Landings of Spanish Mackerel
0.4
Relative Catch Rate
0.8
The annual recreational harvest of Spanish mackerel in NSW is likely to lie between 10 and 100 t. This estimate is based upon the results of the offsite National Recreational and Indigenous Fishing Survey (Henry and Lyle, 2003) and onsite surveys undertaken by I & I NSW.
1.0
Catch
00/01
02/03
04/05
06/07
08/09
0
10
Financial Year
78/79
83/84
88/89
93/94
98/99
03/04
08/09
Financial Year
Commercial landings (including available historical records) of Spanish mackerel for NSW from 1978/79 to 2008/09 for all fishing methods.
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Catch rates of Spanish mackerel harvested using all line methods for NSW. Two indicators are provided: (1) median catch rate (lower solid line); and (2) 90th percentile of the catch rate (upper dashed line). Note that catch rates are not a robust indicator of abundance in many cases. Caution should be applied when interpreting these results.
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Fur ther Reading Collette, B.B. and C.E. Nauen (1983). Scombrids of the World. An Annotated and Illustrated Catalogue of Tunas, Mackerels, Bonitos and Related Species Known to Date. Rome, FAO: 137 pp. Henry, G.W. and J.M. Lyle (2003). The National Recreational and Indigenous Fishing Survey. Final Report to the Fisheries Research & Development Corporation and the Fisheries Action Program Project FRDC 1999/158. NSW Fisheries Final Report Series No. 48. 188 pp. Cronulla, NSW Fisheries. McPherson, G.R. (1992). Age and growth of the narrow-banded Spanish mackerel (Scomberomorus commerson Lacepede, 1800) in north-eastern Queensland waters. Australian Journal of Marine and Freshwater Research 43: 1269-1282. McPherson, G.R. (1993). Reproductive biology of the narrow barred Spanish mackerel (Scomberomorus commerson Lacepede, 1800) in Queensland waters. Asian Fisheries Science 6 (2): 169-182. Queensland Fisheries. (2009). Annual status report - 2009 east coast Spanish mackerel fishery. Queensland, Department of Employment, Economic Development and Innovation: 13 pp. Queensland Fisheries. (2010). Stock status of Queensland’s fisheries resources 2009-10. Queensland, Department of Employment, Economic Development and Innovation: 65 pp. Steffe, S., J. Murphy, D. Chapman, B.E. Tarlington, G.N.G. Gordon and A. Grinberg (1996). An assessment of the impact of offshore recreational fishing in New South Wales on the management of commercial fisheries. Project 94/053. Sydney, NSW Fisheries Research Institute: 139 pp. Welch, D., S. Hoyle, N. Gribble and G. McPherson (2002). Preliminary assessment of the east coast Spanish mackerel fishery in Queensland. Brisbane, Queensland Department of Primary Industries. Please visit the CSIRO website, http://www.marine.csiro.au/caab/ and search for the species code (CAAB) 37 441007, 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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