John Dory

Zeus faber

Method of production — Caught at sea
Capture method — Demersal otter trawl
Capture area — North East Atlantic (FAO 27)
Stock area — All Areas
Stock detail

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Picture of John Dory

Sustainability rating five info

Sustainability overview

John Dory is highly regarded for human consumption It’s easily identifiable with its large dark spot and long spines on the dorsal fin.

The stock status is unknown very little data are collected for the species. There are very few management measures to protect John Dory there is no minimum size or catch limit. Demersal trawls are not very selective but the species is usually a bycatch species and therefore, has a limited impact on other species caught in the trawl. Gill nets can be selective. Both demersal trawls and gill nets can catch endangered, threatened and protected species and interactions with these species must be recorded.

Advice: Avoid eating small John Dory smaller than 35cm (that haven’t had the opportunity to reproduce yet).

Biology

John Dory has a distinctive appearance with its laterally compressed body and large dark “eyespot”. John Dory also known as dory or St Peteras fish is an ambush predator. When it approaches its prey, it opens its huge mouth and sucks it in.

John Dory are found in the Eastern Atlantic from Norway to southern Africa, as well as in the Mediterranean and the Black seas, and the western Pacific and Indian oceans. They are found at depths from 20 m to over 400 m.

John Dory usually lives a solitary life or is found in small schools in inshore waters. They become sexually mature at an age of around 4 years and at a length of 29-35cm. Spawns in June-August off the coasts of southern England, earlier in the Mediterranean. It can reach lengths of 70cm and has a maximum age of about 12 years. John Dory are a relatively vulnerable species.

Stock information

Criterion score: 0.75 info

Stock Area

All Areas

Stock information

The stock status for John Dory is unknown. There are very little data available about the species. There are mixed trends in abundance and the data available for the species are 10 or more years old. Their population trend is generally unknown. Fishing mortality is unknown though, in ICES area 7, catches have declined since 2012. Their resilience is low.

Whilst their populations are unknown, John Dory have been recently considered as a winning species of climate change. With increasing sea temperatures, it is likely that there will be increased amount of suitable habitat for John Dory and their abundances are predicted to increase. Their distributions are shifting northwards with increasing sea temperatures and fishers have recently seeing more of more of them in the North Sea.

Management

Criterion score: 0.75 info

John Dory is not subject to management measures: there are no limits on catches. There is no minimum landing size for the species. There are insufficient species-specific measures to protect the species.

Management controls are enforced regularly through a variety of surveillance activities including VMS, logbooks, dockside monitoring and visual inspections. Compliance rates are thought to be high as infringements seldom occur and therefore are compromise harvest objectives. Since the fleet is predominantly inshore, monitoring, surveillance and enforcement is often reduced due how dispersed and plentiful the fleet are.

Some surveys collect data for the species though, these have not been used to evaluate stock trends.

Capture Information

Criterion score: 0.5 info

Summary
John Dory are normally caught as part of a mixed fishery e.g. where species such as hake are the main retained species. There are many other species caught in trawls, many of which have not received full stock assessments. Some ETP species are caught. John Dory are normally found over soft muddy substrates.

Justification
John Dory live on soft and muddy substrates, close to rocks. Almost all (99%) of catches are made between 20 m and 160 m.Due to the John Dory’s unusual shape, few gear adaptations can feasibly be implemented to increase selectivity. Since the area where John Dory are normally caught is a mixed fishery, measures must be suitable to catch and avoid a vast variety of species. There are general adaptations used in the fishery on beam trawl, demersal trawl and gill nets, though these are not specific to the species.

John dory is retained when caught as bycatch in mixed demersal fisheries targeting hake (Merluccius merluccius), anglerfish (Lophius piscatorius) and megrim (Lepidorhombus whiffiagonis). They are retained as valuable bycatch in trawl and gill net fisheries. Their unusual shape enables easier capture in nets, preventing their escape. To mitigate the impact of capture on the species, rockhoppers are advised on bottom trawling gear.

Alternatives

Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.

Basa, Tra, Catfish or Vietnamese River Cobbler
Bass, seabass (Farmed)
Bream, Gilthead (Farmed)
Cod, Atlantic Cod
Cod, Pacific Cod
Coley, Saithe
Haddock
Hake, Cape
Hake, European
Pollock, Alaska, Walleye
Sturgeon (Farmed)
Tilapia
Whiting

References

"EUMOFA. 2017. Monthly highlights No. 7/2017. Available at: http://www.eumofa.eu/monthly-highlights.

Project Inshore. 2013. John dory: Western Approaches (VIIe-j VIII a,b): gill net. Available at: http://msc.solidproject.co.uk/inshore-uoc.aspx?id=8250&s=&a=

Pinnegar, J. 2017. Fisheries and aquaculture climate science Potential impacts, adaptation and mitigation - overview of current scientific knowledge and cutting-edge developments. Available at: http://www.seafish.org/media/1698860/clg_june2017_fish_aquaclimatescience_cefas2.pdf.

FishBase. 2016. John Dory, Zeus faber. Available at: http://fishbase.sinica.edu.tw/Summary/SpeciesSummary.php?ID=1370&AT=john+dory

Fox C.J., Valcic L. and Veszelovszki A. 2015. Evidence Gathering in Support of Sustainable Scottish Inshore Fisheries: A Pilot Study to Define the Footprint and Activities of Scottish Inshore Fisheries by Identifying Target Fisheries, Habitats and Associated Fish Stocks. Published by MASTS. 190pp. ISBN 978-0-9934256-4-6

Jin, D. et al. 2014. An empirical analysis of portfolio management as a tool for implementing ecosystem-based fishery management. Available at: https://ir.library.oregonstate.edu/concern/conference_proceedings_or_journals/z603qz55s.

ICES. 2012. ICES Implementation of Advice for Data-limited Stocks in 2012 in its 2012 Advice. ICES CM 2012/ACOM 68. 42 pp.

ICES. 2013. Report of the Working Group on Elasmobranch Fishes (WGEF), 17-21 June 2013, Lisbon, Portugal. ICES CM 2013/ACOM:19. 649 pp. "