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Seafood to Avoid
School shark/ Tope/Flake
Scientific name: Galeorhinus galeus
Other
names: makohuarau (Maori), grey shark, grey boy, tope, flake
Ranking: E (Red - Worst Choice)
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Description: School shark is a long-lived and slow growing species that is late to mature. This means the fishery has low overall productivity and, as with most other sharks, the species is highly vulnerable to fishing pressure.
The main concerns with this fishery are: the uncertainty about basic biological information, the unknown sustainability of current catch levels and limits for a long-lived shark species, the absence of quantitative stock assessments, and the lack of a management plan. Set netting for this species risks marine mammal, seabird and non-target fish bycatch and trawling can impact seabed habitats.
The fishery assessment plenary report states: "Estimates of current or reference biomass are not available. ..there are no indications that current catches are not sustainable in the short-term. However, it is not known whether recent catch levels or the current TACCs are sustainable in the long-term, or if they are at levels that will allow the stocks to move towards a size that will support the maximum sustainable yield." (MFish 2007, p804).
Market: New Zealand fish and chip market and exports of $3.3m to main markets in Australia.
Status and sustainable yield
Status: Unknown.
Annual catch limit: Set at 3,437 tonnes in 2007-08.
Recorded catch: Reported landings of 3,102 tonnes in 2005-06.
Population size: Unknown.
Stock trends: Unknown.
Fishing method
Method: Trawling, lining and set netting with some also caught by tuna longliners well offshore.
Habitat damage: Trawling damages benthic habitats .
Bycatch: Juvenile school sharks are caught in harbour set nets and the risk of dolphin and seabird bycatch.
Ecological effects: Impact of trawling on bottom dwelling species diversity and impact of adult removal from the population.
Management
Stock assessment: No quantitative stock assessment.
Management plan: No.
Quota management species: Yes since 1986.
Biology
Distribution: Found throughout New Zealand coastal waters although it is more common in the north. Prefers the shallower waters of the continental shelf, but is known to at least 200m.
Maximum age (years): 50+
Age at sexual maturity: 12-13+
Growth rate: Slow.
Reproductive output: Low.
Age exploited: 10 (uncertain)
References: Report from the Fishery Assessment Plenary, May 2007: stock assessments and yield estimates. Part 3: Pilchard to Yellow-eyed Mullet. 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 | 
