The role of scientific knowledge to inform investors in the Blue Economy The Seychelles tuna fisheries case study Francis Marsac, PhD Financing Sustainable and Climate-Resilient Ocean Economies in Africa Conference 22-23 Feb, Seychelles

KEY figures of Seychelles tuna economy Fisheries sector accounts for 20-25% of the GDP Fish and derived products make >90% of the exports in value 95% of those products are canned tuna 90% of WIO PS catches landed or transshipped in Victoria >30% of WIO tunas caught in the Seychelles EEZ 49 PS vessels operating in WIO, 13 Seychelles-flagged 10% of the population depend on tuna industry and related activities

Outstanding transformation of port-Victoria 1970 - 2003 1983

Longline (deep-dwelling tunas) Purse seine (surface dwelling tunas) Semi-industrial (EEZ) Industrial (high seas)

Average PS catches 2000-2016 The Seychelles EEZ has a strategic location in the core of the WIO purse seine fishing zone

The process of stock assessment Input for the decision-making Restrepo, ISSF The function of Regional Fisheries Management Org.

A tool to summarize status of a fish stock: The Kobe diagram Indicates the current status of a stock with respect to several reference points Target reference points Fmsy : Fishing mortality at the MSY Bmsy : biomass at the MSY Limit reference points Blim : biomasse threshold (% of B0 or Bmsy) Flim : fishing mortality threshold (% of Fmsy) Management objectives : To remain in the green quadrant How to achieve the objectives ? By implementing pre-agreed Harvest strategies Overfishing Overfished Overfishing Not overfished No overfishing Overfished No overfishing Not overfished Flim MSY Fishing mortality ratio (F/Fmsy) Blim Biomass ratio (B/Bmsy)

Current status for Yellowfin and Skipjack 67.6% YELLOWFIN Current status for Yellowfin and Skipjack Management measures : Catch reduction scheme by gear Harvest Control Rule for Skipjack SKIPJACK 47 % overfishing in general has reduced revenues and economic efficiency, increased variability and reduced the resilience of stocks and catches

Short-term projections according to catch scenarios Applying a catch reduction of 10% (2014 baseline), there would still be a 80 à 60% probability to remain below the biomass at MSY, at 3 and 10 years timeline respectively ; and a 65 to 57% probability to be above the fishing mortality at MSY Both being undesirable states

Average catch 1st quarter A threat to local economies : changes in spatial distribution of catches Average catch 1st quarter Catch 1st quarter 1998

Economic impacts OF THE 1998 ANOMALY in seychelles The relocation of the fleet to the East IO, and poor catches for several months in the WIO, substantially reduced the activity in the tuna hub of Port- Victoria (Seychelles) Tuna industry expenditure declined by 42% Same magnitude as the loss in Chilean and Peruvian fishmeal fisheries caused by Nino Overall economic loss for Seychelles : 3.6% of the GDP Robinson et al, Climate Res, 2010

This CHANGE IN SPATIAL PATTERN was CAUSED BY environmental anomalies MLD MLD End of 1997, deeper mixed layer around Seychelles (Positive Dipole mode) and low chlorophyll made tuna less abundant and less vulnerable to the purse seine. Opposite situation occurred in the East Indian Ocean Chlorophyll_a anomalies

Climate change perspective Dramatic changes expected in the RCP 8.5 scenario (IPCC AR-5) Increased temperature Ocean acidification Declining ocean productivity Contrasts in dissolved oxygen levels Bopp et al, 2013

Sketch of possible relocation of purse Seine fishing grounds during 21st Century Seychelles may see its strategic position for PS fleets challenged by other countries The longline gear would not be affected as much as purse seine Favorable conditions for longline could be maintained around Seychelles Opportunity for Seychelles-based longliners Marsac, 2017

Take-home message Robust science is necessary to empower the fisheries sector and provide advice for different governance scenarios Well-managed fisheries (= avoiding overfishing) is a prior condition to ensure sustainability for fish stocks, economic profits and human well-being Strong, responsible and regionally-coordinated fisheries policies mitigate ecosystem impacts of fisheries Environmental monitoring remains essential to adjust/adapt management measures Physical environment and ecosystems Different timescales to be considered Impacts on local economies : to foresee for adaption though innovative strategies