Setting objectives for fisheries management

the role of science and society

Martin Pastoors

Public Hearing, European Parliament, Committee on Fisheries“Management of fishery resources and fishing fleet”

Brussels, 23 November 2011

Q:Is Maximum Sustainable Yield (MSY)

an appropriate target for fisheries management?

Maximum Sustainable Yield (MSY) is not the magic bullet for everything

... but it could provide a direction for travel

it is not the numerical values that count but the way they get established

The theory is (relatively) simple

Catch Revenue

Effort

MSY

MEY MSocY

Maximum Sustainable Yield

Maximum Economic Yield

Maximum Social Yield

Costs

... but the practice is (at least) confusing

Fishing mortality

Three types of “MSY”

MaximumSustainable

Yield

Fmsy Bmsy

BiomassMSY

MSY in regulations is ill-described

“maintain or restore stocks to levels that can produce the maximum sustainable yield with the aim of achieving these goals for depleted stocks on an urgent basis and where possible not later than 2015”

Johannesburg declaration, 2002

= Bmsy?

MSY is a single-species concept: how to deal with ecosystem links?

Seal

Cod Herring

Zoo-plankton

Can science estimate “MSY”?

No, not really

...but we can come up with proxies

Fmed, F0.1, Fmax, Fmt, Fsim

Lessons from the introduction of the precautionary approach

MSY approach = Fish less?

Reference points for MSY are approximations, not carved in stone

Fisheries science can inform decision-making but cannot make decisions

Should not

Use the MSY concept:get stakeholders talking,

move in the right direction

Extra

Maximum Sustainable Yield is a “new” element in EU fisheries policy

“Issues” with MSY

• Unclear meaning• Single species• Estimation aspects

MSY became prominent through the Johannesburg Declaration 2002

Maximum Economic Yield (MEY) is achieved at lower effort than

Maximum Sustainable Yield (MSY)

Catch Revenue

Effort

MSY

MEY Costs

FMEY < FMSY

Theory

Adding up Bmsy is problematic

Charts based on: Froese et al 2010Example: North Sea fish stocks

Bmsy Current biomass

Flatfish

Predators

Prey

x 7.3

3. MSY is an equilibrium approach applied to a dynamic system