Scientific name: |
Pseudocaranx dentex |
Other names: |
araara, kopapa, komutumutu, raumarie (Maori), blue gill, jack fish, silver trevally (Australia / UK), carangue (France), Minamishimaaji (Japan) |
Depending on how trevally is caught it can be a good seafood choice. If it is caught by purse seine then it is ranked amber and ok to eat. If it is caught by trawl then it is rated red, worst choice, and should be avoided.
Trevally is a long-lived species (up to 45 years) that lives near the seabed when young, but schools as adults in the open water, where they feed on krill and other plankton. It is common around many parts of the North Island and the top half of the South Island, and most abundant at depths of around 80m. It is caught year round, mainly around the North Island in conjunction with the snapper trawl fishery. It is also caught by purse seiners in the Bay of Plenty and a small amount by set nets.
Trevally is caught by purse seine vessels in the north and trawls in the south. The purse seine fishery has a lower impact that trawl-caught fish. The absence of a quantitative stock assessment for most areas, the uncertainty of the stock status, and the lack of a management plan are of concern. Trawling catches non-target fish and, when fished at the bottom or using bottom trawl gear, may cause considerable damage to seabed habitats and ecosystems. The bottom trawl fishery captures seabirds and marine mammals and there is a risk of captures of critically endangered Maui’s dolphins off the west coast of the North Island.
Not certified under any scheme.
The markets for trevally are in New Zealand, with main export markets of Saudi Arabia, France and Mayotte. It had an export value of $6.45 million in 2015, double the value of $3.2 million in 2008.
Asssessment output
The two main methods used to catch trevally were compared: purse seine and trawling. Purse seine-caught fish were ranked amber. Trawl-caught fish ranked red.
| Score: | Both trawl and purse seine – D |
| Population size: | Uncertain for all stocks apart from TRE 7, which is very likely to be above target (40%Bo). |
| Annual catch limit: | Limit set at 3,933 tonnes since 2001-02. |
| Recorded catch: | Reported landings of 3521 tonnes in 2014-15. East Coast fishery has had its catch limit well-exceeded four times in the last ten years. |
| Stock trends: | Uncertain except for TRE 7, where the stock has been relatively stable but may decline over the next 5 years. |
| MSY Status: | Uncertain, apart from an assessment of TRE 7, which indicates that the current stock is likely to be at or just above the target. |
| The Ministry of Primary Industries assessment plenary report includes: | TRE1 (Cape Reinga to eastern Bay of Plenty) and TRE 2 (Eastern North Island to Kapiti): “It is not known if recent catches are sustainable.” TRE 7 (Western New Zealand North & South Islands): “Very Likely to be at or above the target (40%Bo). Since the mid–1990s spawning biomass has remained relatively stable. Model projections indicate that the biomass of TRE 7 is About as Likely as Not to decline over the next 5 years (to 2019), but with low probability of dropping below 40% SB0 by 2019.” (MPI, 2016, p1524 – 1127). |
| Score: | Both trawl and purse seine – D |
| Distribution: | Common around the North Island and northern South Island, with most trevally found along the north east and north west coasts of the North Island at a depth of 80m. |
| Maximum age (years): | 40+ |
| Age at sexual maturity: | 3-5 |
| Growth rate: | Moderate to low |
| Reproductive output: | Low to high |
| Age exploited: | 3-4 |
| Ability to recover: | Moderate |
| Score: | Purse seine – A, trawl – E |
| Fishing method(s): | Bottom trawl, bottom pair trawl and purse seine dominate catches. Other methods (e.g. set net and bottom longline) are less than 10% of catches. In QMA1 purse seine is between 25 to 50% of the catch, with most of the remainder (about 70%) caught by bottom trawl or bottom pair trawl. In other areas, bottom trawl represents over 90% of the catch. Trevally is also caught as a bycatch in snapper, red gurnard, kahawai and john dory bottom trawl fisheries. |
| Habitat damage: |
Trawl: There is considerable damage to seafloor communities when caught by bottom trawl or midwater trawl which touches the bottom. Impacts include habitat modification, loss of biodiversity, loss of benthic productivity, modification of important breeding and juvenile fish habitat and redistribution of sediment. Purse seine: Low. |
| Habitat of particular significance: |
hasn’t been defined in New Zealand. |
| Bycatch: |
Purse seine: Bycatch includes jack mackerel, blue mackerel, yellowfin tuna, sunfish, striped and blue marlin and vulnerable sharks and rays. Trawl: As a bycatch species itself, a range of other fish species are caught as bycatch, including other commercial species (snapper, red gurnard, kahawai, john dory) as well as non-target species. |
| Ecological effects: | The combined effects of destroying seafloor habitats and non-target fish bycatch can have considerable ecological implications. |
| Score: | Purse seine – A, Trawl – D |
| Bycatch: |
Purse seine: Low, but with a residual risk of seabird bycatch. There has been no reported marine mammal and seabird bycatch in the trevally target fishery. Trawl: Inshore trawl fisheries (including some trevally) have an estimated seabird bycatch of 4370 seabirds. This includes cryptic mortality. Reported species include white-capped albatross, Salvin’s albatross and white-chinned petrels. Fur seal captures have also been estimated in the inshore trawl fisheries at about 20 per year. There is also the risk of Maui and Hector’s dolphin captures in inshore trawl fisheries where endangered Hector’s dolphin and critically endangered Maui’s dolphin are found. |
| Score: | B |
| Management component: | Single species – but stock boundaries appear to cross quota areas and QMA1 has two stocks based in East Northland and the Bay of Plenty. |
| Score: | QMA1 – C, other QMAs – D |
| Quota Management Species: | Yes since 1986. |
| Catch limits: | Yes |
| Management plan: | There is no approved inshore plan. |
| Stock assessment: | A revised quantitative assessment in TRE 7 in 2015. Other areas have no accepted stock assessment. |
| Research: | Research has been focused on monitoring and assessments of TRE 7 and TRE 1. |
| Observer coverage: | Observer coverage averaged 1.47% in the trawl fishery. There was no observer coverage outside TRE 1 and the northern part of TRE 8. There was coverage of 9.9% in the purse seine fishery; however, none of this coverage is likely to be spatially or temporally representative of the fishing effort, as the purse seine observer effort is targeted at skipjack tuna and not trevally. There is also a shed sampling programme focused on TRE 1 and TRE 7. |
Fisheries map
Taken from the Ministry for Primary Industries’ Plenary report for fisheries management.
References
Paste here.