fisheries & aquaculture - mekong · pdf file• dominated by pangasius, ... •...

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Fisheries & Aquaculture

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Presentation Structure• 1: Introduction to Fisheries and climate change in the LMB

– Capture Fisheries & Aquaculture Sector

– Fisheries based Livelihoods

– Macro trends and drivers

– Probable impact of climate change on LMB fisheries

• 2 CAM for assessing local vulnerabilities of fisheries– Overlay of Catchments and Agro-ecological zones

– The Aquatic Species Database

– Aquatic Species & Agro-ecological zones

• 3: Example of CAM application: Chiang rai, Thailand– Capture Fisheries

– Aquaculture

– Overall vulnerability of climate change to Fisheries Sector in Chiang rai.

• 4. Wrap up.

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1. LMB Fisheries Overview

• Capture Fisheries• The number of fish species in the Mekong basin is current estimated at around 1,200.

• Estimated to be around 2 million tonnes per year. This is around 2% of the World’s total marine & freshwater capture fishery. Varies considerably from year to year. More water=more fish.

• Capture fisheries still probably under reported in the statistics. E.g. Some countries do not include fish production from rice fields and swamps in its inland fisheries statistics.

• Aquaculture• Latest estimates = 1.9 million tones. (almost 50% of total LMB fish production)

• Wide range of indigenous and exotic fish ‘closed’ and available.

• Dominated by Pangasius, export orientated culture in Vietnam’s Mekong Delta

• Intensive and super-intensive aquaculture systems developed in Thailand and Vietnam.

• Small-scale aquaculture an important source of food at the village/household level, in many areas

• Many aquaculture systems still dependent upon capture fisheries for wild caught juveniles for stocking and low value fish, for feed.

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IMPORTANCE OF FISH FOR FOOD SECURITY

• From HORTLE, K.G. (2007) Consumption and the yield of fish and other aquatic animals from the Lower Mekong Basin. MRC Technical Paper No. 16, Mekong River Commission, Vientiane. 87 pp.

• ‘Fish-eating cultures’. Thailand is perhaps the only country in the world where increased GDP has not been accompanied by a corresponding increase in meat consumption.

• GIven current population growth in the LMB, (approx 1%) an additional 21,000 tonnes of fish is required, each year, to maintain current levels of fish consumption.

• Processed fish products; fish paste etc. are important during low fish production periods.

Cambodia Lao PDR Thailand Vietnam Average / Total

Fish consumption (kg) /capita/year

36.8 28.6 29.1 39.0 33.6

Extrapolated fish production

(tonnes/year)

587,004 208,503 911,485 852,823 2,559,815

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Capture? Culture? An example from Steung Treng market

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The Decline of Capture Fisheries ?Some Pressures on the capture fishery

• Overfishing, from increased numbers of fishers and sizes of gears.

• Loss of connectivity, Reduced pulse effect.

• Damming of tributaries reducing biodiversity and production from migratory species.

• Loss of productivity through habitat destruction/change,

• Aggressive fishing methods, e.g. explosives.

• Radical changes in land use patterns that change run off patterns from upland areas.

• Establishment of exotic fish populations from aquaculture escapees,

• Water pollution from urban centres, industry and intensive aquaculture.

• Despite these enormous pressures, there appears to be no decline in overall fish production in the LMB.

• Robustness. It’s amazing that the system hasn’t crashed already.

• However, declining catches of large, high-value and highly specialist species, replaced by smaller, less valuable, (in monetary terms) fish are reported.

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Spot the endangered fish!

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The Meteoric Rise of Aquaculture!

• Exponential growth of aquaculture in the LMB. Will soon surpass capture fisheries.

• Wide range of exotic and indigenous fish species are available.

• Insatiable international demand for Pangasius & Tiger Shrimp.

• Huge demand for lower value cultured fish for domestic consumption.

• Perhaps the only realistic hope of maintaining current LMB fish consumption levels as populations rise.

• Cheap fish meal and carbohydrate sources available for aquaculture feeds.

• Large freshwater wetland areas that can be used for the expansion of inland aquaculture. But limited scope for further coastal aquaculture expansion.

• Strong promotion of aquaculture and pond digging by Governments.

• Some excellent (blue-fingered) aquaculture technicians working in the region.

• Demand for restocking of depleted fisheries with hatchery produced seed, including endangered fish species.

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Climate change threats to LMB Capture Fisheries & Aquaculture

How will these affect the sector?

• Temperature increases

• Timing of the monsoon

• Increased rainfall

• Longer dry periods

• Increased erosion

• Increased CO2 levels

• Increased sea levels

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Some LMB fisheries climate change impact hypotheses to test.

Capture Fisheries

• The reduced connectivity of habitats and the Mekong ‘pulse effect, will affect the productivity of highly migratory fish species. Climate change may exacerbate this.

• Increasing dominance of ‘black fish’ in wild fish catches?

• Disappearance of habitat specific fish species; dominance of small species ‘generalists’?

• Capture fisheries may be less vulnerable to climate change, than farming systems?

• Invasive fish, (which tend to be generalists) will become more prevalent in the capture fishery

Aquaculture

• Intensive culture systems affected more than semi intensive or extensive systems?

• Higher elevation aquaculture likely to gain in importance?

• More balanced production systems will emerge, as environmental extremes are reached

• The diversity of species and production systems allows farmers to have plenty of ‘tools’ with which to adapt and modify aquaculture systems, as environmental and climate changes arise.

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The CAM Fisheries Vulnerability Assessment.

• The challenge. To develop a methodology that facilitates a robust vulnerability assessment of the fisheries, (i.e. capture fisheries and aquaculture) in a particular areas of interest.

• Note: In assessing the climate change vulnerability of fisheries, it appears to be important to treat capture fisheries and aquaculture differently.

• Capture fisheries can be treated in a similar way to the NTFP component, i.e. focused on species.

• Aquaculture can be treated in a similar way to the Livestock component, i.e. focused on farming systems.

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The Aquatic Species Database

At the heart of the Fisheries CAM is

the Aquatic Species Database, (could be

combined with the NTFP database)

Currently has records for 30 aquatic

species from a range of Mekong

environments.

Each ‘fish’ is classified by

•Type: Upland, migratory, black,

estuarine, or exotic

•IUCN status: endangered-> of least

concern

•Use: Aquaculture, capture fisheries,

commercial, food security.

•Information on biology, migration,

water quality tolerances etc is entered

(there are many gaps).

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• Why are these classifications of fish suitable for climate change assessments?

• Upland fish: Inhabiting cool forest streams, these species are likely to be the most vulnerable to temperature increases and may well to shift their range to higher elevations.

• Migratory (white) fish: Sensitive to poor water quality and loss of connectivity of their ‘highways’ and habitats

• Black fish: Highly resilient, air breathing swamp fish that have evolved to withstand harsh environmental conditions. Likely to be climate change resilient.

• Estuarine fish: Likely to be the more resilient to sea level rise in the Delta.

• Exotic fish: Likely to compete with indigenous species as temperatures increase.

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Overlay of catchments on ecological zones,,

allows for estimates of which species are likely

to be where.

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‘Hotspot’ Capture Fisheries Vulnerability Assessment

• Through the overlay, each of the ‘fish’ in the database have been assessed, (by reference materials and personal experience) for their likelihood of being found in each of the ecological zones.

• Each species is then coded for each zone as follows:

– Found: Reference to species in report or personal experience: 100% certainty

– Likely to be found: No direct reference to the species but environmental conditions suggest it would be found with >50% confidence

– Possibly found: No reference to the species but environmental conditions suggest it could be found but with <50% confidence

– Not found: Extremely unlikely that the species would be found in the zone. 0% probability

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Check list compiled for the presence of the 30 aquatic animal species in each zone

Fish Species Type of fish Aquaculture

Food

security IUCN status

Low Elevation Dry

Broadleaf Forest

1 Anadara granosa Estuarine Y Y

Least

concern Not Found

2 Bangana behri Upland N Y Vulnerable Found

3 Barbonymus gonionotus Migratory Y Y

Least

concern Found

4 Channa lucius Upland N N

Least

concern Possibly found

5 Channa striatus Black Y Y

Least

concern Found

6 Cirrhinus microlepis Migratory Y Y Vulnerable Found

7 Clarias batrachus Black Y Y

Least

concern Found

8 Colossoma macropomum Exotic Y N invasive Possibly found

9 Cyclocheilichthys enoplos Migratory N Y

Least

concern Found

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Site Ecozones Indicator Species

Chiangrai MEDBF plusHembf, lembf, ufwl

•Tor tambroides (U) •Cyclocheilichthys enoplos (M)•Trichogaster pectoralis (B)

Mondulkiri LEDBF/ MEDBF •Scaphiodonichthys acanthopterus (U)•Hypsibarbus malcolmi (M)•Mastocembalus armatus (B)

Kien Giang LLAA •Macrobrachium rosenbergii (M) •Channa straitus (B)•Anadosa granosa (E)

Gia Lai MEDBF Bangana behri (U)Probarbus jullianii (M)Hemibagrus nemurus (B)

Khammoune LEMBF hembf • Channa lacius (U)•Puntioplites falcifer (M)•Clarias batrachus (B)

For each of the 5 ARCC hotspots, 3 species have been selected representing: Upland fish, U (if relevant); Migratory fish M; Black fish B; Estuarine E (if relevant)

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Capture Fisheries CAM for Chiangrai

• Climate change tables and charts provided by ARCC GIS team for Chiang rai

• Proxy species representing important fish groups in Chiangrai, (black, migratory, upland ) selected and database accessed for biological information.

• CAM conducted, (best done by a group) for the three proxy species identified.

• Threats; level of exposure; sensitivity impact and adaptive capacity determined

• Most and least vulnerable species (groups) identified

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Some assumptions and notes

• This methodology assumes that the proxy fish selected, represents the wider group and that the majority of fish in each group will respond similarly to climate change variables.

• Individual fish species that are of particular interest, can be assessed as individual species, rather than proxies for a wider group.

• This methodology does not work with invasive species. We need to modify the CAM tool so that the vulnerability of the environment to an invasive species, in the light of climate change is assessed rather than the well-being of the species.

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Capture Fish CAM Example. Chiang Rai

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‘Hotspot’ Aquaculture Climate Change Vulnerability Assessment

• Focuses on systems & species.

• Aquaculture Systems classified as:

– Intensive (Ponds, Cages/Pens/Hapa

– Extensive (Ponds, Ricefields, Mudflats)

• Species (from 30 species Database)

– Exotic species: e.g. Common carp. Tilapia

– Indigenous species: E.g. Tiger shrimp, Blood cockle, Pangasisus

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Aquaculture CAM for Chiangrai

1. Climate change tables and charts provided by ARCC GIS team for Chiangrai

2. Identify aquaculture systems and popular species cultured.

3. Link information from the aquatic species database, to the aquaculture system, E.g. Intensive pond tilapia aquaculture

4. Carry out CAM on the aquaculture system and species to determine climate change vulnerability.

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Aquaculture CAM Example. Chiang Rai

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Initial Fisheries CAM results for Chiangrai

CAPTURE FISHERIES AQUACULTURE

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Main Conclusions from Chiangrai fisheries CAM

• Using this CAM methodology for Chiangrai appears to support the hypotheses that:

– Upland and migratory fish appear to be vulnerable to environmental changes from resulting from climate change.

– Black fish appear to be more ‘climate-proof’ than migratory fish & upland fish and may be expected to increase in the proportion of fish catches, as temperatures increase.

– Aquaculture appears to be more vulnerable to climate change than capture fisheries.

– Intensive aquaculture appears to be more vulnerable to climate change than semi-intensive or extensive systems. Even though the more intensive systems would have greater adaptive capacity in the form of technology and management.

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Looking ahead• The Fish Cam methodology needs to be tested and

further developed under the ARCC.

• But it may provide an approach for projects to periodically assess the fisheries sector for climate change vulnerabilities in specified areas.

• The continuous addition of new information (ground truth’ing), enrichment of the species (and systems) databases and verification of the ecological zone check list would allow for better judgements to be made and would strengthen the approach.

• The model should provide agood basis for discussions on adaptation and management interventions

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So that’s the fisheries sector. But hang on……..

Shouldn’t we be combining/balancing(?) the sector-focused CAM assessments and attempting: Integrated Livelihoods CAMs?

Try characterizing this man. Fisherman, Farmer, Rancher or NTFP collector?

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Thanks for listening