Is the Balc Sea Ready for Ecosystem- Based Fisheries Management? Jeremy S. Collie Graduate School of Oceanography University of Rhode Island

Michael J. Fogarty Ecosystem Assessment Program Northeast Fisheries Science Center Outline

• Ecosystem-Based Fisheries Management (EBFM) means different things to different people • Some myths concerning EBFM • Implementaon of EBFM in the United States • Opportunies and constraints for EBFM in the Balc Sea o Cod-herring-sprat trophic interacons o Mulspecies models and reference points o Economic, spaal, and polical consideraons • Is the Balc Sea ready for EBFM?

U.S. Commission on Ocean Policy: Ecosystem-Based Management

“U.S. ocean and coastal resources should be managed to reflect the relaonships among all ecosystem components, including human and nonhuman species and the environments in which they live. Applying this principle will require defining relevant geographic management areas based on ecosystem, rather than polical, boundaries (USCOP 2004)”

Some Myths Concerning EBFM Link et al. (2015) Fisheries 40:155-233-160 •EBFM is too complex and poorly defined to implement •EBFM lacks mandates & appropriate governance structures •EBFM data requirements are prohibive •EBFM always results in overly conservave advice •EBFM is a panacea for a complex social- ecological system •EBFM is cost-prohibive to implement Management Connuum: From Single Species to Ecosystem-Based Management

Courtesy Dr. Jason Link How does EBFM differ from convenonal fisheries management?

Human dimensions

Target Fishery species

Technical Climate interactions How does EBFM differ from convenonal fisheries management?

Human dimensions

Target Fishery species

Trophic Technical Habitat Climate interactions interactions Confronting Complexity: Can We Use Simpler Models and Analytical Approaches?

“Optimal” Model Model Complexity Inaccuracy for Prediction

Measurement

Prediction Error Error Systematic Bias

Model Complexity

Collie et al. 2014. Fish & Fisheries Aggregate Mulspecies Models: Tradeoffs Between Yield and Biodiversity

mMSY Yield 100 Collapse

75

50

PercentMaximum of 25

0 0 0.25 0.5 0.75 1 Exploitation Rate Worm et al. 2011. Science Opportunies and Constraints for Implementaon of EBFM in the Balc

• Relavely ‘Simple’ Fishery Ecosystem • Extensive Scienfic Background Knowledge • Environment Strongly Impacted by Human Acvity • Differing Naonal Objecves and Perspecves Cod-Herring-Sprat Interacons

Cod Sprat Herring 500 1500 1000 300 CodSSB (kt) 500 Herring and Sprat SSB (kt) Sprat andHerring 100

1980 1990 2000 2010

Year 700 600 500 400 1800 300 1600 1400

200 1200 CodSSB (kt) 1000

100 800 600 SSBHerring (kt)

0 400 0 500 1000 1500 2000

Sprat SSB (kt) A MULTISPECIES INTERACTIVE STOCHASTIC OPERATIVE MODEL Noel Holmgren, Niclas Norrström, Michele Casini Methods: • Age-structured model for each stock (cod-herring-sprat) • Four functions control the changes in the variables: recruitment, mortality, growth and recruitment weight • Environmental pressures are included in the functions: reproductive volume, salinity, temperature • Stock interactions are included in the mortality of prey and the growth of the predator. • Functions are fitted to ICES assessment data

• Find Fmsy for each species such that all species are at their Fmsy levels (Nash Equilibrium)

Bild 12 Cod Herring Sprat

1,0 1,0 0,50 0,9 0,9 0,305 0,295 0,45 0,8 0,8 0,40 0,7 0,7 0,300 0,35 0,6 0,6 0,30 0,5 0,5 Sprat F Sprat F Herring F Herring 0,25 0,7 0,4 0,4 0,300 0,20 0,3 0,44 0,3 0,6 0,48 0,2 0,52 0,2 0,15 0,5 0,1 0,1 0,10 Fishing mortality 0,1 0,2 0,3 0,4 0,5 0,4 0,6 0,8 1,0 1,2 1,4 0,4 0,6 0,8 1,0 1,2 1,4 Herring F Cod F Cod F Nash Equilibrium

1,0 1,0 0,50 Upper row shows the 0,9 0,9 0,45 540 FMSY landscape for 0,8 0,8 0,40 180 each species. 0,7 0,7 520 0,35 1000 0,6 0,6 0,30 0,5 0,5 The Fishing mortality Sprat F 220 Sprat F 500 Herring F Herring 0,25 900 0,4 0,4 480 Nash Equilibrium can 0,20 800 0,3 260 0,3 be found by iteration 0,2 0,2 0,15 0,1 0,1 0,10 (solid lines). 0,1 0,2 0,3 0,4 0,5 0,4 0,6 0,8 1,0 1,2 1,4 0,4 0,6 0,8 1,0 1,2 1,4 Herring F Cod F Cod F Middle row shows

1,0 1,0 0,50 BMSY landscape.

0,9 50 0,9 0,45 0,8 0,8 0,40 Bottom row shows 0,7 0,7 0,35 130 yield landscape. 0,6 70 0,6 0,30 0,5 0,5 Sprat F Sprat F Herring F Herring 0,25 600 0,4 90 0,4 120 500 0,20 0,3 110 0,3 400 110 0,2 0,2 0,15 0,1 0,1 0,10 0,1 0,2 0,3 0,4 0,5 0,4 0,6 0,8 1,0 1,2 1,4 0,4 0,6 0,8 1,0 1,2 1,4 Bild 13 Herring F Cod F Cod F MSY (t tons) BMSY (t tons) FMSY REFERENCE POINTS

FMSY BMSY MSY Cod 0,47 211 76 Herring 0,30 460 115 Sprat 0,54 794 402

These multispecies reference points are sensible compared with ICES advice.

FMSY Blim Bpa

Cod (2014) 0,46 63 88 Herring 0,22 430 600 Sprat 0,26 410 570

Bild 14 The multispecies model implies higher rates of fishing for Herring and Sprat

Distribuon of Catches from Pelagic and Demersal Trawls in the Balc Sea

HelCom Balc Sea Environment Proceedings No. 122 Regional trade-offs from mulspecies maximum sustainable yield opons (Voss et al. 2014)

Opmize profits from cod, Opmize profits from sprat, condional on sprat Bpa condional on cod Bpa Myth busting and parting questions

• The road to EBFM has been well defined if not yet well travelled; • In the Balc Sea there is a mandate from HELCOM and provision of fisheries advice from ICES; • The Balc Sea is data rich; • EBFM does not always result in more conservave advice; • Do ecosystem data and scienfic understanding provide a sufficient basis for EBFM? • Is the management system ready for EBFM?