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Keith Carlisle Anthony Rogers Jiaxi Wang March 29, 2013

Evaluating Trade-Offs in an Ecosystem-Based Fishery Management Paradigm: An Exploration through Analysis of the Atlantic Butterfish and Longfin Squid Fisheries. Keith Carlisle Anthony Rogers Jiaxi Wang March 29, 2013. Statement of Objectives.

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Keith Carlisle Anthony Rogers Jiaxi Wang March 29, 2013

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  1. Evaluating Trade-Offs in an Ecosystem-Based Fishery Management Paradigm: An Exploration through Analysis of the Atlantic Butterfish and Longfin Squid Fisheries Keith Carlisle Anthony Rogers Jiaxi Wang March 29, 2013

  2. Statement of Objectives Longfin Squid and Atlantic Butterfish Fisheries • Conduct geospatial and statistical analysis to determine patterns in landings and bycatch • Analyze landings and price data to better characterize the fisheries • Conduct bioeconomic modeling of the fisheries to determine the effects of management constraints and ecosystem interactions on economic rents

  3. Context for Masters Project:Transition to Ecosystem-Based Fisheries Management Integrated Multi-Species Management (ecosystem & fishery interactions) Ecosystem Approach: integrated management of all activities that impact marine ecosystem health Single Species (Stock) Management Messy Picture Habitat, climate, etc.; energy development, shipping, agriculture … Predation, competition, bycatch, total social and economic benefits Mortality, recruitment, harvest, etc. The norm today The next step (our focus for the MP) We’re years away! Graphic adapted from J. Link, What Does Ecosystem-Based Management Mean, Fisheries vol 27 no 4 (2002)

  4. Management Issue:Butterfish Rebound: How to Allocate Allowable Biological Catch Higher Landings Quota = Rebuild Directed Butterfish Fishery Higher Bycatch Cap = Prevent Early Closure of Longfin Squid Fishery Fixed Number of Total Allowable Butterfish Catch

  5. Management of the Fisheries • Limited Access Program • Gear Restrictions • Trimester System Trimester I Trimester III JAN FEB MAR APRIL MAY JUNE JULY AUG SEPT OCT NOV DEC

  6. GEOSPATIAL ANALYSIS OF OBSERVER DATA Are There Patterns in Landings and Bycatch?

  7. Longfin Squid and Atlantic Butterfish Landings by Trimester, 2007 - 2011

  8. 2.3% 1.6% 6.2%

  9. Butterfish Bycatch Ratio and Estimated Catch in 2011 Source: Mid-Atlantic Fishery Management Council

  10. ANALYSIS OF LANDINGS DATA Are There Distinct Inshore and Offshore Groups In the Longfin Squid Fishery?

  11. Inshore and Offshore Longfin Squid Landers 2002 - 2011 Percentage unique to the inshore fishery ranged from 28% to 58% (mean = 42%) Percentage unique to the offshore fishery ranged from 30% to 89% (mean = 56%)

  12. Analysis of Landings Data: Trends in the Longfin Squid Fishery • 2013 quota allocation (22,029 mt): • 43% to Trimester 1 • 17% to Trimester 2 • 40% to Trimester 3 • Percent of landings in Trimester 2 for past 5 years: • 2008: 32% • 2009: 35% • 2010: 33% • 2011: 46% • 2012: 61%

  13. ANALYSIS OF LANDINGS AND PRICE DATA How Significant are Revenues from Longfin Squid Relative to Other Species Harvested by the Inshore and Offshore Groups?

  14. Top Offshore Longfin Squid LandersProportion of 2011 Revenue by Species Landed Trimester 1 Trimester 2 Butterfish = 0% Longfin Squid = majority of revenue Longfin Squid = negligible revenue Focus is on Ilex Squid Trimester 3 Revenue: Longfin Squid = 26% Total 2011 Revenue: Longfin Squid = 22%

  15. Top Inshore Longfin Squid LandersProportion of 2011 Revenue by Species Landed Trimester 2 Trimester 1 Longfin squid is important, but no species = majority of revenues Inshore group relies heavily on longfin squid revenues in trimester 2 Trimester 3 Revenue: Longfin Squid = 12% Total 2011 Revenue: Longfin Squid = 46%

  16. BIOECONOMIC MODELING OF THE LONGFIN SQUID AND ATLANTIC BUTTERFISH FISHERIES What Can We Learn About the Effects of Management Constraints and Ecosystem Interactions on Economic Rents?

  17. Modeling the Fisheries Maximize across time: (profits from longfin harvest) + (profits from butterfish harvest) Keeping in mind that… Change in butterfish stock = (growth) – (predation) – (bycatch) – (direct harvest) & Change in longfin squid stock = (growth) + (benefits of more butterfish) – (direct harvest)

  18. Modeling the Fisheries Maximize across time: (profits from longfin harvest) + (profits from butterfish harvest) Keeping in mind that… Change in butterfish stock = (growth) – (predation) – (bycatch) – (direct harvest) & Change in longfin squid stock = (growth) + (benefits of more butterfish) – (direct harvest)

  19. Why do we care about Predation?

  20. Modeling the Fisheries Maximize across time: (profits from longfin harvest) + (profits from butterfish harvest) Keeping in mind that… Change in butterfish stock = (growth) – (predation) – (bycatch) – (direct harvest) & Change in longfin squid stock = (growth) + (benefits of more butterfish) – (direct harvest)

  21. Why do we care about the Bycatch rate?

  22. Why do we care about the Bycatch rate?

  23. Why do we care about how much the Bycatch buffer is? A fun calculation 3,884 mt - 1,984 mt = 1,900 mt (current butterfish (predicted butterfish (amount of butterfish bycatch cap) harvest at squid cap) left as a buffer) 4,188,783 lbs x $0.82 = $3,434,802.06 (amount left over, (2011 average converted to pounds) price per pound)

  24. Modeling the Fisheries Maximize across time: (profits from longfin harvest) + (profits from butterfish harvest) Keeping in mind that… Change in butterfish stock = (growth) – (predation) – (bycatch) – (direct harvest) & Change in longfin squid stock = (growth) + (benefits of more butterfish) – (direct harvest)

  25. Modeling the Benefits of More Butterfish

  26. Conclusions • Based on the observer data, the rate of butterfish bycatch appears to be related to distance from shore (highest 20 – 100 miles from shore) • This means that the inshore longfin squid fishery (trimester 2) has a lower bycatch rate than the offshore fishery

  27. Conclusions • Trimester 2 landings and participation has constituted a larger share of the longfin squid fishery in recent years. • Longfin squid represents a significant portion of total annual revenues for the trimester 2 fishermen. • The Council should consider allocating more longfin squid to the trimester 2 quota (currently 17%).

  28. Conclusions • Based upon our modeling, premature closure of the longfin squid fishery on account of the butterfish bycatch cap appears extremely unlikely under any reasonable scenario. • There are potentially additional economic rents that could be captured if more butterfish are allocated away from the longfin squid cap and to the direct butterfish fishery.

  29. Conclusions • Ecosystem-based fisheries management requires an extraordinary amount of data -- even a simple 2-species model is extremely data hungry. • If we're serious about ecosystem-based fisheries management in this country, a significant amount of resources will need to be directed to research.

  30. We wish to acknowledge and thank: • Marty Smith, our advisor on this MP, for his invaluable advice and support, and • Rich Seagraves and Jason Didden from the Mid-Atlantic Fishery Management Council for conceiving of this project, providing us with the necessary data, and patiently answering all of our questions

  31. Questions?

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