Vulnerability of coastal fisheries - Chapter 9 -

1. Vulnerability of coastal fisheries - Chapter 9 - Presented by Morgan Pratchett

3. Importance of coastal fisheriesFiji

4. Coastal Fisheries Production Gillett 2009

5. Coastal Fisheries Production

6. What are coastal (inshore) fisheries? • Demersal fish • Nearshore pelagics • Invertebrates What are not considered (so far) • Deepwater snapper • Sharks

7. i. Demersal fish

8. ii. Nearshore pelagic fish

9. iii. Invertebrates

10. Coastal fisheries - Fiji 4,180 t/yr 5,270 t/yr 17,450 t/yr

11. Indirect effects of climate change Seagrass area Coral cover

13. 65% decline in abundance and diversity of fishes

14. Effects of habitat degradation 0.5 0 -0.5 -1 Macroalgae Proportional change Habitat complexity Coral cover 0 1 2 3 4 5 6 7 8 9 10 Time after extensive coral loss (years)

15. Effects of habitat degradation 0.5 0 -0.5 -1 Macroalgae Proportional change Habitat complexity Coral reef fishes Coral cover 0 1 2 3 4 5 6 7 8 9 10 Time after extensive coral loss (years)

16. Catch composition GeneralistsNot vulnerable Reef associatedVulnerable Coral associatedHighly vulnerable

17. Catch composition - Fiji

18. Catch composition - Fiji

19. Direct effects of climate change pH Temperature

20. Effects of temperature Growth (mg/week) Acanthochromis polyacanthus Maximum growth 28-30oC Projected increase 3oC by 2100 Temperature (oC) Zarco Perello and Pratchett 2012

21. Effects of temperature Declines in: growth lifespan reproduction Fewer & smaller fishes Growth (mg/week) Maximum growth 28-30oC Projected increase 3oC by 2100 Temperature (oC) Zarco Perello and Pratchett 2012

22. Effects of temperature Normal spawning temperature

23. Effects of ocean acidification Abalone Byrne 20120

24. Effects of ocean acidification Munday et al 2012

25. Effects of ocean acidification Munday et al2012

26. 100 80 60 40 20 0 • 2100 • Response conditional on emission scenario • Up to 50% decline in production, due mostly to habitat degradation and effects on fishes • Declines may be partly offset by slight increase in nearshore pelagic fishes Projected changes in maximum fisheries production 2030 2-5% decline in demersal fishes Potential increase in nearshore pelagics 2-5% decline in invertebrates B1 A2 2000 2020 2040 2060 2080 2100

27. Projected coastal fisheries productionFiji Page 54, Country summaries

28. Priority adaptations • Protect the structural complexity and biological diversity of coral reefs, mangroves and sea grasses to sustain fisheries and maximize adaptation potential. • Recognise the ecological importance of specific fishes (e.g, herbivorous fishes on coral reefs), and ensure stocks of these species are sufficient to maintain key ecosystem functions.

29. Priority adaptations 3. Diversify coastal fisheries activities to target species and habitats that will be least affected (or favoured) by climate change 4. Build the effects of climate change into fisheries management and planning, particularly the need to maintain adequate spawning stocks to overcome the shocks of greater climate extremes

30. Conclusions • Coastal fisheries are critically important for both food security and livelihoods across the Pacific • Effects of climate change will compound upon existing anthropogenic disturbances and pressures (e.g., overfishing).

31. Conclusions • Improved data on coastal fisheries catches is important for monitoring, understanding and predicting the effects of climate change on coastal fisheries Reporting • subsistence fisheries catches • separate data for distinct fisheries sectors and species, wherever possible

32. Conclusions • Up until 2035, effects of climate change will be difficult to detect against the backdrop of existing anthropogenic disturbances, but urgent action on climate change is critical to minimize long-term impacts 100 80 60 % change B1 A2 2000 2020 2040 2060 2080 2100