Integrating movement information from tagging data into stock assessment models: a review and perspective

1. Integrating movement information from tagging data into stock assessment models: a review and perspective Marriot Hotel, La Jolla, 4-7 October 2011

2. Project Evolution • Tuna tagging campaigns have been implemented episodically since the 1970s in the western and central Pacific Ocean, Eastern Pacific Ocean, Indian Ocean. • Tagging experiments provide data for estimation of mortalities, growth and movement. • Pacific Tuna Tagging Project is the most recent, commencing in 2006 releasing both conventional and electronic tagged tuna.

3. Project Evolution • 2010 a mid-term review was undertaken to evaluate progress and develop the work plan for the coming years. • Clear outcome of the mid-term review was the limited use of electronic tagging data in tuna stock assessment models. • Electronic tagging data viewed as potentially influential for estimating movement. • Tuna Assessment models, such as MFCL, integrate catch, effort, length and conventional tagging data.

4. Tagging Data - movement • Conventional tags – location and date of release and recapture. • Currently the only data regularly used in tuna SA models in the Pacific Ocean. • The tagging data (the most direct measure) however is often swamped by the length data when estimating movement parameters.

5. Tagging Data - movement • Electronic tags – location and date of release and recapture and an estimate of the most probable track(s). • Currently not used in tuna SA models in the Pacific Ocean. • Sample size low. • A further issue for consideration, electronic tags provide continuous data, SA models are discreet.

6. Project Objectives • How do we improve the integration of tagging data in tuna assessment models? Tasks • Prepare data for use in tuna SA’s. Include estimating most probable tracks for electronic tags from the WCPO & Hawaii tagging programs. • Undertaken at SPC but opportunity for wider participation.

7. Project Objectives • Review/synthesis on approaches for incorporating electronic tagging data into tuna SAs. • Objective of the meeting but discussion and topics not limited to electronic tagging. (PFRP would like a manuscript as an output) • Implement best options for both conventional and electronic • Budget to progress

8. Workshop • Get together as much thinking power on this topic as possible. • Participation is a mix of those with experience in geolocation, stock assessment and tuna biology. • Draft agenda with some presentation to stimulate and promote discussion. • Encourage as much discussion as possible.

9. Workshop • Maunder, Kleiber, Nicol to summarise discussion and regularly report back to group. • We have allocated 4 days for the workshop. Expectation of 3 full days and the option of Friday for further discussion. • A number of participants who could not make the meeting but will contribute remotely by assisting with manuscript preparations • Focus Questions to help guide discussion.

10. Focus Questions Movement models What types of movement should be considered: diffusion, advection, site fidelity, density dependent, temporal variability, environmentally driven? Estimating movement and movement behavior from tagging data Can advection diffusion models deal with area specific parameters? Incorporating movement into stock assessment models Integrating tagging data into stock assessment modelsHow should area be assigned to archival tag data?

11. Agenda Introduction and welcome • History of the project and purpose of meeting • Simon Nicol to provide an Introduction to the workshop, why it has come about and what the workshop expectations and provide a framework for summarising the discussion of the workshop Overview of movement models and modeling strategies and paradigms • Pierre Kleiber to provide an introduction to establish the vocabulary for the meeting • Juan Valero to provide a presentation on workable paradigms for modeling movement within a stock assessment model

12. Agenda Estimating movement and movement behavior from tagging data Conventional tags • Pierre Kleiber to provide presentation on Eulerian Models (eg Sibert/Adam -- grid point model; Kleiber/Hampton -- cell boundary (block transfer) model). • Discussion to be focussed on the data needs, analytical assumptions and computational requirements. Archival tags • Tim Lam to provide presentation of approaches to analysing geolocation data and key assumptions. • Discussion to be focussed on the data needs, analytical assumptions and computational requirements.

13. Agenda Incorporating movement into stock assessment models • Juan Valero to provide presentation on the lessons learned from the long history of using tagging data in the Pacific halibut assessment • Felipe Carvalho to provide a presentation on Integrating the Brownian Bridge Movement Model into a Spatially Explicit Age-structured Model • Shige Iwata to provide discussion points on the pacific bluefin tagging and its use in the species stock assessment • Simon Hoyle to provide discussion on parameter and structural uncertainty and stock assessment and the role that tagging data plays to reduce uncertainty in each • Discussion focussed on the conversion between movement model paradigms; Incorporating movement estimates vs. incorporating movement behavior

14. Agenda Integrating tagging data into stock assessment models • Ian Taylor to provide an overview presentation followed by presentations by Hoyle/Kleiber – Multifan examples, Maunder/Da Silva – SS3 examples, Senina/Royer – SEAPODYM • Simon Nicol to provide a summary of the integration of electronic tagging data in the stock assessment for swordfish in the southwestern Pacific Ocean • Mark Maunder to provide a summary of the integration of electronic tagging data into the assessment of southern bluefin tuna. • Discussion to be focussed on current and alternative approaches for integrating tagging data into stock assessment Project workplan and overview manuscript • Simon Nicol to rapporteur discussion and provide regular summaries. A potential output of the workshop is a draft manuscript authored by all participants. Discussion to allocate tasks to complete manuscript.

15. Other information • 30 min break for morning and afternoon coffee • 1hr 30mins lunch