1. Brussels the 3rd of December 2008 - COBECOS 1 COMPUTER MODEL Costs and Benefits of Control Strategies SIXTH FRAMEWORK PROGRAMME Policy-Oriented Research Jenny Nord, Brussels 3 rd of December 2008

2. Brussels the 3rd of December 2008 - COBECOS 2 Outline 1. Description 2. Functionality 3. Simulations using different levels of Enforcement effort Fines Shadow value of biomass 4. Future work

3. Brussels the 3rd of December 2008 - COBECOS 3 COBECOS Computer model Written in the statistical programme R Based on the theory developed within the COBECOS Available with manual, tutorial and example data R and text editors are freely downloadable online Two versions of the programme: Basic version - single exploited stock and single enforcement type. Extended version - allows for multiple stock and multiple enforcement types.

4. Brussels the 3rd of December 2008 - COBECOS 4 Functionality of the programme Defines: theoretical relationships between enforcement effort and enforcement costs and enforcement effort and probability of detecting violations. Defines functional forms of private and social benefit Evaluate the private and social benefit at different levels of enforcement effort Finds the optimal level of enforcement level and evaluates the social benefits at this level Allows the user to investigate the robustness of the estimated parameters by introducing stochasticity

5. Brussels the 3rd of December 2008 - COBECOS 5 Simulations Example fishery: Hake with onboard observers Is the social benefit from the Hake fishery maximized at the current level onboard inspections? How will the harvest rate of Hake change if the fines for violation are increased? Taking costly enforcement into consideration how many onboard inspections should we invest in? How does a change in the value of leaving the Hake behind to let it grow and spawn influence the social benefit?

6. Brussels the 3rd of December 2008 - COBECOS 6 Relationship between enforcement effort (e) and costs and enforcement effort (e) and probability of detection Π (e) TypeEnforcment effort Cost Observer0.1151.237 Observer0.3761.716 Observer0.5181.87 Observer0.5511.899 TypeEnforcement Effort Probability Observer0.2015750.517901 Observer0.37253070.811373 Observer0.4486590.895643 Observer0.6304690.99 TypeEP.ModelEPpar1EPpar2EPpar3EC.ModECpar1ECpar2ECpar3Effort_MinEffort_Max ObserverNA nonlinearNA0 01

7. Brussels the 3rd of December 2008 - COBECOS 7 Relationship between enforcement effort and C(e) and enforcement effort and Π (e)

8. Brussels the 3rd of December 2008 - COBECOS 8 Calculating the social benefits Two options: 1. User defined enforcement effort. The programme displays the associated private and social benefits as well as the harvest rate. 2. Optimisation of social benefit. The program finds the enforcement level that maximizes the social benefit. ParameterValue Price1 Costs0.5 Biomass1000 Fine1 Shadow value0.2 Enforcement effort0.1

9. Brussels the 3rd of December 2008 - COBECOS 9 Calculating social benefits

10. Brussels the 3rd of December 2008 - COBECOS 10 Optimization of enforcement effort

11. Brussels the 3rd of December 2008 - COBECOS 11 Increased fine level by 70 % (1-1.7)

12. Brussels the 3rd of December 2008 - COBECOS 12 Increased shadow value (0.2 – 0.5)

13. Brussels the 3rd of December 2008 - COBECOS 13 Accuracy of the results

14. Brussels the 3rd of December 2008 - COBECOS 14 Future development Tested and used with real data by each case study Modifications and improvements Inclusion of multiple enforcement types in the basic model? Development of a user friendly interface

15. Brussels the 3rd of December 2008 - COBECOS 15 Thank you for your attention!