Fishing practise, science and management, a French case study Cédric Briand ÅLSEMINARIUM i Stockholm den 20 oktober 2005

I.Status of fisheries and current management practises in France II.A practical example of management : the Vilaine III.What consequence will have the setting of management plans on the quantity of glass eel available for transport ?

Landings of the glass eel fisheries in France Estimation for 2004 FAO 76 T T Statistics Loss of 40 % >

Export from France Source Ofimer, Castelnaud, Thibault 2004 Export =65 T, FAO expertise > 76 T

Yellow eel catches (T) Yellow eel fisheries landings 2001 Atlantic 220 T Mediterranean 900 T Mediterranean 300 T

Management by hydrographical district Separate management for marine and fluvial areas Separate management in the Atlantic and the Mediterranean areas Habitat restoration along with fishery management measures Eel management in France

The Vilaine km² II. A practical example of management : the Vilaine

Exploitation rate 96%

Piège

Targets – 700 kg glass eel > freshwater –0.3 eels/m² of riffle Measures –Reduction of the fishing season –Fishing trips after closure of the fishery Management in the Vilaine

Total annual catch for the Vilaine fishery

< >100 Yellow eel density in the basin /electrofishing

15 trips 60 trips

Fishing ladder efficiency = Trapping ladder catches/Stock in the estuary (marking recaptures) % The efficiency of the fishing ladder has diminished 5 kg

700 kg Target of 700 kg never reached

R² = /11/0201/01/0301/03/0301/05/03 Glass eel recruitment (Kg) p=0, p=0, p=0,5 Modelling of glass eel recruitment Modelling of April recruitment

/11/0201/12/0201/01/0301/02/0301/03/0301/04/0301/05/03 Glass eel (Kg) Standing stock always lower than expected Cumulated recruitment Recruitment Standing Stock Fisheryclosure Fishery catch Models should account for mortality and settlement

Summary Glass eels have no chance to die naturally Estuarine stock is probably below density- dependent migration The Vilaine is an extreme case, also an habitat problem

How much glass eels are available for transport once French basins achieve the target ? What is the target ? III Consequence of the management plans for the resource available for transport

Bpa 40 % of pristine production

40 % of potential production at the actual recruitment Zpa

How do we implement Bpa? The following discussion applies to Zpa What does 40 % SPR means when fishing several stages ?  63 % SPR per stage if fishing of both yellow eel and glass eel  73 % SPR per stage in the Loire where silver eel are also fished About Targets

Glass eel fisheries : 2005 Fishing limitations  -13 T % SPR marine fishery=70 to 87 Loire Gironde Adour %SPR=4 %SPR=20

Eel repartition is receding in the Gironde and the Loire

Decrease of the total catch of yellow eel fisheries in the Gironde and Loire estuaries

Low fishing efficiency also corresponds to large carrying capacity ?

Conclusion  About 60 T available after management measures (guess)  French basins now seem to be below carrying capacity ?  Market problem

Tack