Research on monkfish (anglerfish) Research on monkfish (anglerfish) Lophius piscatorius Lophius piscatorius

at the NAFC Marine Centreat the NAFC Marine CentreNorwegian: Breiflabb,

Havtaske, Marulk,

Faroese: Havtaska Danish: Bredflab, HavtaskeIcelandic: SkötuselsurFinnish: Merikrotti

Dr Chevonne Laurenson

When?When?• Research started in July 1997 and has been

ongoing since then.

Why?• Research started because the fishery had rapidly

developed during the late 1980’s and early 1990’s but little was known of the biology;

• The first monkfish Total Allowable Quota was implemented for waters around Shetland (Area IV) in 1998 but was not based on biological or survey data.

Importance of monkfishImportance of monkfish• The fishery developed as a result of the quotas for

“traditional” species (cod, haddock, whiting) being reduced.• Several vessels were built specifically to target monkfish,

others altered their gear to that they could better target them.• In the mid-1990’s monkfish accounted for approx. 25% by

weight of the landings from the 4 main species (monkfish, cod, haddock & whiting) and represented 50% of the value.

Several projects…..

– EU project 1997 – 1999– Teaching Company Scheme (NAFC & SFPO

partnership project) 2000 – 2002– PhD completed 2003, Publications 2004 & 05– Nordic projects (Norway, Faroe, Iceland and NAFC)

2002-03 & 2003-05– Contract with FRS, Aberdeen 05-06.

Research areas

• Catch Data • Age and Growth• Reproduction• Tagging• Behaviour• Diet

Summary of important findings …..

Catch data

• Relationship between monkfish length and water depth (bigger – deeper trend)

• Possibly using some inshore areas as nursery grounds

• Distribution patchy and seasonal differences in catch rates

Age & growth

• Important for stock assessment inputs• Ageing using hard parts analysis (otoliths) was

verified by identifying modes in length frequency distributions in time series data and growth rates were verified using growth data from tagged monkfish

• Growth rates were found to average around 10 cm per year.

Tagging study• Important for assessing the amount of mixing between

different “stocks”.• This tagging study was the first on monkfish in Northern

European waters and is the largest to date.• Almost 1800 monkfish tagged around Shetland, some in 2000

but mainly in summer 2001.• To Aug 2006, 83 recaptures reported (4.7%).• Days at liberty 5 – 2129.

Tagging study

Latest recapture July 2006 at Norway after 2129 days since tagging. Growth from 45 – 109 cm (10.9 cm/yr).

Reproduction

• Important for stock assessment inputs. • The mean length at which maturity is reached is

58cm for males and 98cm for females.• Fishery mainly relying on juvenile monkfish – ripe

females rarely caught in fishery around Shetland

Behaviour• First publication of analysed in situ video footage of

behaviour.

• Footage obtained by Remotely Operated Vehicle (ROV) deployed at Schiehallion and Foinhaven oil fields.

• The behaviours included:• resting and sit-and-wait behaviours, • concealment behaviour by recess excavation, • cough responses, • prey detection and attraction responses, • walking behaviour, • attack behaviours.

Behaviour

Current management issues …..• Catches and TACs do not correspond. • Fishermen could catch significantly more than the

quotas allow.• The 2006 TAC included a mid-term review of

scientific evidence and data. Data collected at NAFC during 05-06 comprised a significant proportion of the evidence that went forward to the STECF. The outcome was a recommended increase of 10% on the 06 TAC. This is however still to be implemented.