1. Projected changes to aquaculture

2. Based on…….

3. Outline Freshwater aquaculture (tilapia, milkfish, freshwater prawn)
Vulnerability of freshwater aquaculture
Coastal aquaculture (marine shrimp, marine ornamentals)
Vulnerability of coastal aquaculture

4. Tilapia
Food security
Cage culture
Household subsistence production

5. Tilapia Livelihoods Cage culture Semi-intensive ponds Aquaponics
PNG ,000 households with tilapia farms

6. Tilapia Tilapia farming is expanding in the region
PNG ,000 households
Fiji produces tonnes per year
Vanuatu tonnes p.a., hatchery established
Samoa has 25 farms

7. Freshwater prawn Macrobrachium
Hatchery-based culture (M. rosenbergii)
Capture-based culture (M. lar)
Fiji produces about 25 t per year

8. Vulnerability of freshwater aquaculture

9. Tilapia, freshwater prawn
Likely to benefit from climate change
Higher rainfall and warmer temperatures will allow farming in more places and at higher altitudes

10. Tilapia, freshwater prawn
Increased risks from flooding
Stratification from higher temperatures causes de-oxygenation

11. How should we respond? Build fish ponds to avoid more severe floods
Photo: Avinash Singh

12. How should we respond?
Increase aeration to combat stratification

13. Conclusion
Freshwater pond aquaculture is likely to be favoured by climate change
Source: Pickering et al. (2011)

14. Coastal aquaculture - livelihoods

15. Vulnerability of coastal aquaculture

16. Ocean acidification
Source: IPCC (2007), Ganachaud et al. (2011)

17. Temperature Spatial variation in temperature increase 2035 2050* 2035
2100
* Based on B1 2100
Source: Lough et al. (2011)

18. Sea-level rise Projection 2035 2050 2100 IPCC 8 cm 18-38 cm 23-51 cm
Semi-empirical
20-30 cm cm cm

19. Marine shrimp
Expected to benefit in short term from higher temperatures
In the long-term, the main threats to shrimp culture are:
Sea-level rise
Ocean acidification
Pathogens
Scarcity of fishmeal?

20. Marine shrimp Sea-level rise will make it difficult to:
Now: crop in progress
Sea-level rise will make it difficult to:
dry out ponds between crops
harvest shrimp
Now: pond preparation
Future: poor pond prep.
Future: difficult to harvest

21. How should we adapt
Modify shrimp ponds to drain well

22. Giant clams and marine ornamentals
2035
2050
2100
Effects due to:
Increased temperature
Ocean acidification
Greater runoff
More-intense cyclones

23. How should we adapt? Grow-out animals at greater depth (cooler waters)
Identify sites where CO2 is reduced

24. Outlook for coastal aquaculture

25. Conclusion Scope for development over next 30-40 years
Production efficiency is likely to be reduced