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Seafood to Avoid
Swordfish
Scientific name: Xiphias gladius
Other names: broadbill, broadbill swordfish, and paea.
Ranking: E (Red - Worst Choice)
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Description: Swordfish are targeted and a bycatch in the northern bigeye and southern bluefin tuna longline fisheries. The New Zealand catch is a small part of the Pacific fishery which is now managed by the Western and Central Pacific Fisheries Commission.
The main concerns with this fishery are: uncertainty about the state of the stocks, the bycatch of sharks, seabirds and fur seals, and uncertainty over stock assessments and catch limits, and no management plan.
The fishery assessment plenary report states: "Although the estimates of stock status relative to swordfish to standard biological reference points (eg Bmsy) could not identify whether the stock was currently overfished or not, this assessment [2006] has indicated consistent declines in stock abundance in recent years, and most model projections predict further declines at current levels of fishing mortality. É the WCPFC Scientific Committee recommended as a precautionary measure that there be no increase in fishing mortality on this stock, as this is likely to move the stock towards an overfished state." (MFish 2007, p953).
Market: Main markets are Japan, Australia and USA. The export value of all tuna species combined was $42 million in 2002.
Status and sustainable yield
Status: Uncertain.
Annual catch limit: Catch limit of 885 tonnes in 2004 with 3 times as many females caught as males.
Recorded catch: Latest reported annual landings of 560 tonnes in 2005-06.
Population size: South Pacific migratory population.
Stock trends: Uncertain.
Fishing method
Method: Longlining around the North Island.
Habitat damage: Low.
Bycatch: Seabird, sharks and New Zealand fur seals are caught in the longline fishery. In December 2006, a single surface longline vessel caught 51 albatrosses and 2 sea turtles.
Ecological effects: Removal of large predator species as bycatch in the longline fishery.
Management
Stock assessment: A preliminary assessment in 2006 by the Western and Central Pacific Fisheries Commission (WCPFC) (Kolody et al 2006).
Management plan: No.
Quota Management Species: Yes in 2004.
Biology
Distribution: Swordfish are caught on the west coast and east coast of the North Island, plus around the Kermadecs.
Maximum age (years): 20?
Age at sexual maturity: 9-10
Growth rate: Medium.
Reproductive output: Medium.
Age exploited: ?
References: Overview of the Western and Central Pacific Ocean Tuna Fisheries, 2000, A Lewis and P Williams, Oceanic Fisheries Programme, Secretariat of the Pacific Community, New Caledonia, August 2001; National Tuna Fishery Report 2001 Ð New Zealand, T Murray and L Griggs, NIWA; Kolody, D., N. Davies, and R. Campbell. (2006b). SW Pacific Swordfish Stock Status Summary from multiple assessment models. WCPFC-SC2; SA WP-7. Report from the Fishery Assessment Plenary, May 2007: stock assessments and yield estimates. Part 1: Albacore to Groper. Sullivan et al, Science Group, Ministry of Fisheries; Guidebook to New Zealand Commercial Fish Species, Revised Edition 1990, NZ Fishing Industry Board.
This page was updated on 9 November, 2007 |
