reliable and robust indicators for control chart based fisheries management
DESCRIPTION
Reliable and robust indicators for control chart based fisheries management. Deepak George Pazhayamadom 1 , Emer Rogan 1 , Ciaran Kelly 2 , Edward Codling 3. 1 Department of Zoology, Ecology and Plant Science, University College Cork, Ireland 2 Marine Institute, Galway, Ireland - PowerPoint PPT PresentationTRANSCRIPT
Reliable and robust indicators for control chart based fisheries management
1 Department of Zoology, Ecology and Plant Science, University College Cork, Ireland2 Marine Institute, Galway, Ireland3 University of Essex, UK
PhD : “Application of signal detection methods to fisheries management system”
Control chart : Cumulative Sum (CUSUM) Control Chart
Indicators : Types of age based catch indicators
Deepak George Pazhayamadom 1, Emer Rogan 1, Ciaran Kelly 2, Edward Codling3
An operating model that simulates fictional stocks (Iteration used: 1000)
Phase 1 : Self-populate and stabilize
Phase 2 : Low fishing mortality
Phase 3 Scenario – 1 : No management with high fishing mortality
Scenario – 2 : Managed using Total Allowable Catch (TAC)
Indicators were calculated from catch data
Type 1: Catch numbers (CN)
Type 2: Catch weights (CW)
Type 3: Positive proportions of CN
Type 4: Negative proportions of CN
Type 5: Positive proportions of CW
Type 6: Negative proportions of CW
Type 7: Positive proportions of average CW
Type 8: Negative proportions of average CW
Three fisheries (correlated with SSB) :
Celtic Sea and Bay of Biscay MegrimNorth East Atlantic MackerelIrish Sea Cod
Neg
ative
Pr
opor
tions
Posi
tive
Prop
ortio
ns
Age 1 Age 2 Age 3 Age 4 Age 5 Age 6
1 4 5 6 7 82 3
1 4 5 6 7 82 3
1 4 5 6 7 82 3
Boxplots: Indicator correlations with SSB (Scenario – 1 : No Management)
Type 1: Catch numbers (CN)
Type 2: Catch weights (CW)
Type 3: Positive proportions of CN
Type 4: Negative proportions of CN
Type 5: Positive proportions of CW
Type 6: Negative proportions of CW
Type 7: Positive proportions of average CW
Type 8: Negative proportions of average CW
Megrim (CS&BB)
Cod (IS)
Mackerel (NEA)
1 4 5 6 7 82 3
1 4 5 6 7 82 3
1 4 5 6 7 82 3
Boxplots: Indicator correlations with SSB (Scenario – 2 : TAC Management)
Type 1: Catch numbers (CN)
Type 2: Catch weights (CW)
Type 3: Positive proportions of CN
Type 4: Negative proportions of CN
Type 5: Positive proportions of CW
Type 6: Negative proportions of CW
Type 7: Positive proportions of average CW
Type 8: Negative proportions of average CW
Megrim (CS&BB)
Cod (IS)
Mackerel (NEA)
Megrim (CS&BB)
Positive
High
Type 1: Catch numbers (CN)
Type 2: Catch weights (CW)
Type 3: Positive proportions of CN
Type 4: Negative proportions of CN
Type 5: Positive proportions of CW
Type 6: Negative proportions of CW
Type 7: Positive proportions of average CW
Type 8: Negative proportions of average CW
Mackerel (NEA)
Positive / High
Cod (IS)
Positive
High
• Scenario 1 : Types 1,2,3,5• Scenario 2 : Type 3 and 5
