Fish in the Mekong from a BFP point of view
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The document discusses the author's interest in fish in the Mekong River from a food-poverty-environment perspective and questions around fish yields, demands, threats and research gaps. It notes that fish provide important food and livelihoods but yields are unclear and may be threatened by dams and other changes, and more study is needed on trends, demands, sustainability and management opportunities.
Fish in the Mekong from a BFP point of view
- 1. Fish in the Mekong from a BFP point of view (by a non-expert, who is really asking for advice rather than trying to tell you about fish) Mac Kirby, Mohammed Mainuddin, CSIRO Cali workshop, February 2008
- 2. Outline • Why am I interested in fish? • What does the literature tell me? • What are the gaps?
- 3. Why am I interested? • The BFP considers water - food - poverty in the Mekong • Fish are a key part of the food story and the livelihood story • They are linked to the environment and hence the sustainability story • They may be very vulnerable to expected changes • The literature didn’t seem to tell me what I wanted to know
- 4. Key questions • What is the yield of fish, and the trend in yields? • What is the food security / livelihood impact of that yield? • What are the likely demands in the future? • Is the yield likely to meet the projected demand? • What threatens the prospects of yield meeting projected demand? • What can be done to ensure that yield meets projected demand? • What are the research gaps (if any)?
- 5. Fisheries - yield • Very important inland fisheries - especially capture fisheries Tonle Sap and rapidly increasing aquaculture in delta • Estimates of yield unclear - consumption estimates regarded as more reliable and upper bounds are 2-3 x production ht estimates. o ug • However, few trend estimates for consumption. vie ws • Current growth rate unclear (uncertainre nd estimates), but maybe 0.5 m tonnes last ten ce a mainly aquaculture years, -a dvi Change in measurements ary min 800000 reli Production, tonnes 600000 P 400000 200000 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Year Total Capture Aquaculture Total - high estimate
- 6. Production estimates 40000 400000 Cambodia 35000 Laos 350000 30000 Production, T 300000 Aquaculture 25000 Capture Production, T 250000 20000 ht 200000 15000 150000 100000 10000 so ug w 5000 50000 0 re vie 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 nd 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 a Production, ton dvice 2000 Other farm product Farm shrim ed ed p Vietnam a Production, 000 ton 250000 ry - Farm fish ed Thailand 1500 Sea product ina 200000 Captured Inland product elim Produciton, T 1000 150000 100000 Pr 500 50000 0 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Year
- 7. Production estimates - spatial Capture Aquaculture
- 8. Consumption Cambodia • MRC estimates for Cambodia range from 250,000 to 720,000, and have increased in recent times • Upper figure is 65 kg/person/year • Other estimates range from 10 to 49-80 (FAO) • Other estimates have increased recently • Is the change in estimates a trend or a change in method or data adequacy? (Much the latter for the MRC?) Change in measurements 800000 Production, tonnes 600000 400000 200000 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Year Total Capture Aquaculture Total - high estimate
- 9. Basin - 2000 Production, Consumption Per capita Per capita production consumption m tonnes m tonnes kg/person/y kg/person/y Cambodia 0.1 0.7 9 65 Laos 0.03 0.2 6 42 Thailand 0.2 1.2 9 53 Vietnam 0.6 1.0 35 60 Basin 0.9 3.1 15 55
- 10. Food - livelihoods 1500 1,000 Cambodia 800 Laos GVP, million $ GVP, million $ 1000 600 400 500 200 0 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Year Year Crop Livestock Fish low estimate Crop Livestock Fisheries Fish - high estimate 5000 Thailand 5000 Vietnam 4000 GVP, million $ 4000 GVP, million $ 3000 3000 2000 2000 1000 1000 0 1995 1996 1997 1998 1999 2000 2001 2002 2003 0 Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Crop Livestock Fish low estimate Crop Year Livestock Inland fisheries Total Thai fish , Mekong agriculture
- 11. Fisheries growth prospects? • Demand will increase due to population increase and diet change • Expected increase ~ 1 m tonnes by 2020, 3.5 m tonnes by 2050 • Current growth rate unclear (uncertain estimates), but maybe 0.5 m tonnes last ten years, mainly aquaculture 1400000 1200000 Change in measurements 1000000 All fish, tonnes 800000 600000 400000 200000 0 1991 1993 1995 1997 1999 2001 2003 2005 Laos Thailand Cambodia Vietnam VCH VMD
- 12. Fisheries growth prospects? • Evidence of overfishing in Tonle Sap and elsewhere - shift in species and fewer large individuals • Yield maintained by increased effort (classic fishery development trajectory?) • Capture fishery seems unlikely to expand greatly (except perhaps increased effort before a crash?) • Aquaculture will expand more in delta - but what about upstream (freshwater)? Rice-fish systems in Laos?
- 13. Threats and growth prospects? • More flow more fish - Dai fishery in Tonle Sap river • Expect flow changes (dams) to lead to decline in yield • Can we really extrapolate this? • Process understanding that more flood in Tonle Sap (and elsewhere) releases more resources and will lead to greater production, hence more catch
- 14. Flow changes Phnom Penh reach China Increased dam storage for hydropower and increased areas of irrigated agriculture (one scenario only) Dry season flows not increased as much as dam Myanmar development only - water diverted for irrigation Laos Luang Prabang ~ 4m Tonnes extra rice plus hydropower vs impact on flood dependent ecosystems and fisheries? Thailand Observed flow Phnom Penh Calculated flow 100000 Tonle Sap 90000 80000 Cambodia Vietnam 70000 500 km Phnom Penh cm 60000 Flow, m 50000 40000 30000 20000 10000 0 1 12 23 34 45 56 67 78 89 100 111 122 133 144 155 166 Months
- 15. Climate change China Phnom Penh reach Increased intensity of wet season Myanmar Greater flood peaks Laos More destructive - but also may help preserve flood Luang Prabang dependent ecosystems and fisheries Thailand 140000 Current Tonle Sap Clim change ate 120000 Cambodia Vietnam 100000 flow, mcm/mo 500 km Phnom Penh 80000 60000 40000 20000 0 0 50 100 150 200 months
- 16. What can be done for future yield? • Maintain capture fisheries – stop overfishing – stop dams? Probably not – stop really bad dams (Pak Mun, Khone falls) – operate dams for environmental flows – fish bypass (fish ladder) – stop navigation blasting? (key areas only?) • Increase yields – aquaculture only hope? – Multi use systems – Local governance issues
- 17. What can be done for future yield? • Or, – build the dams, – go for growth and increasing wealth, – distribute the benefits (compensation downstream) – buy food from elsewhere (is it conclusively proven that yield declines will be dramatic?) – Monitor declines (attribution problem)
- 18. Research gaps Question Gaps Yield and trends? Publish More studies Consumption trend estimates Food and livelihoods? More studies Likely demands? Whole diet estimates taking account of growing wealth & urban shift (changing diet), growing population and global markets (ie more studies) Yield meet demands? Fishery growth projection, capture and aquaculture, taking account of sustainability Threats? Test real extent of flow change threat for the whole river Opportunities? Stop worst Manage others (environmental flows) Aquaculture, multi-use, local governance