Transcript Economic implications of projected changes to tuna

Projected changes
to coastal aquaculture
Presented by
Timothy Pickering
Authors
This presentation is based on Chapter 11 ‘Vulnerability of
aquaculture in the tropical Pacific to climate change’ in the
book Vulnerability of Tropical Pacific Fisheries and
Aquaculture to Climate Change, edited by JD Bell, JE
Johnson and AJ Hobday and published by SPC in 2011.
The authors of Chapter 11 are: Timothy Pickering, Ben
Ponia, Cathy Hair, Paul Southgate, Elvira Poloczanska, Luc
Della Patrona, Antoine Teitelbaum, Chadag Mohan,
Michael Phillips, Johann Bell and Sena De Silva
•Coastal aquaculture
(mariculture) already makes
a significant contribution to
some Pacific economies
•It has unrealised potential
in other PICTs
•But future plans could be
derailed by projected
climate changes
Current and projected mariculture
production
Pearls
Marine shrimp
Seaweed
(Kappaphycus)
Marine finfish
Batfish (P. orbicularis)
Barramundi
Grouper (Serranidae)
Other species
Mud crab
Edible Oysters
Culture-based fisheries: restocking
Sea cucumber
Giant clam
Trochus
Green snail
Annual value of aquaculture
• Total value in 2007
was US$ 211 m
• Pearl farming in
French Polynesia
dominates
• Next is shrimp in
New Caledonia
• Together, >90% of
total value
Annual value of aquaculture commodity production
Livelihoods
Shrimp
Pearl
Contribution of aquaculture to GDP
• Aquaculture provides 22% of fisheries
contribution to GDP across the region
Projected production
• Without considering the effects of cliamte
change, aquaculture production is
optimistically forecast to be to be worth USD
320 million by 2025 *
• Growth mainly driven by expansion of existing
commodities, and via adoption of these
commodities by additional PICTs
* But note SPC report ‘Opportunities for the Development of the Pacific
Islands Mariculture Sector‘
Vulnerability of mariculture
Projected climate change
Source: Lough et al. (2011), Ganachaud et al. (2011)
Ocean acidification
Source: IPCC (2007), Ganachaud et al. (2011)
Temperature
2035
2050*
Spatial variation
in temperature
increase
2035
* Based on B1 2100
2100
Source: Lough et al. (2011)
Projected impacts
• Mariculture faces major
uncertainties
• Poor knowledge about
effects of seawater
acidification on shell
formation
• Pearl aquaculture is more
vulnerable to acidification
than shrimp
Acidification and pearls
If projected changes in seawater pH adversely affect
pearl oyster spat and adults, or pearl quality, then
industry will be highly vulnerable
High-quality Fiji Pearls
Poor lustre, defects
Pearl farming
Hunter Pearls hatchery, Fiji Islands
• Vulnerable to cyclones
but may benefit from
sea-level rise
Storm surge during Cyclone Tomas,
February 2010
Shrimp farming
Now:
• Industry faces both
benefits and risks from
climate change
• Climatic conditions for
shrimp farming in
subtropics are likely to
improve, subject reduced
temperature fluctuation
Future: good
Future: bad
Shrimp farming
The main threats to shrimp aquaculture stem from:
• Acidification
• Sea-level rise
• Scarcity of fishmeal
• Pathogens
Shrimp farming
Now: crop in progress
• Sea-level rise will
make ponds
impossible to dry
between crops
Now: pond preparation
Future: poor pond preparation
Future: difficult to harvest
Kappaphycus seaweed
• Seaweed is vulnerable
to seawater
temperature >30oC
Ice-ice
• Reduced salinity due to
more rainfall stresses
seaweed
• Cause “ice-ice” and
Epiphytic Filamentous
Algae (EFA) outbreaks
• Reduced nutrient supply
will slow growth
EFA
Marine fish, shellfish
• Mariculture of fish and
shellfish faces major
uncertainties
• Possible effects of
seawater acidification
on larval fish
and shells
Aquatic animal diseases
• Higher temperatures
caused increased
prevalence of pathogens
• Nature and extent of
future aquatic animal
disease risks are not clear
White Spot Virus WSV
Summary of vulnerability
Summary of vulnerability
Key responses and adaptations
How should we adapt?
• Expect production losses from extreme events
and ‘unexpected’ causes
• Ensure that financial planning for enterprises
can absorb such shocks
How should we adapt?
• Grow pearls at greater depth for final nacre
Photo: Leanne Hunter
Source: Pickering et al. (2011)
How should we adapt?
• Long term data collection to identify sites where
conditions for nacre growth may be better
• Progressively switch to hatchery production
Photo: Rusiate Vadiga
How should we adapt?
• Build new shrimp ponds where drainage will
not be affected by sea level rise
How should we adapt?
Move shrimp ponds
landward or to higher
ground
Adopt more intensive
farming methods that
use less land and water
How should we adapt?
• Build up walls and floors of existing shrimp ponds
Suitable sediment for
shrimp and meiofauna
Source: Della Patrona et al. (2011)
How should we adapt?
• Select sites for seaweed farms near upwelling areas
and at low risk from increased freshwater runoff
• Use temperature- and salinity-tolerant strains to
avoid “ice-ice” and EFA
Photo: Gideon Tiroba
Photo: George Steinmetz
Outlook for mariculture
Pearl farming
• Difficult to project
production of pearls
until more is known
about effects of
seawater acidification
Shrimp farming
• New Caledonia could still
double production (to 4000
tonnes per year and 1000
livelihoods)
• Fiji could develop to 1000
tonnes in the medium term
• PNG could develop to 2000
tonnes
• But rofit margins will be lower
Kappaphycus seaweed
• Medium-term targets of
~1000 tonnes per year
(engaging hundreds of
households) for Fiji, Kiribati
PNG and Solomon Islands ,
should still be achievable
• But not in the same places,
by the same methods, or
with the same varieties
Other commodities
• Marine finfish, mud crab,
corals, giant clam, trochus,
and sea cucumber are
fledgling industries
Conclusion
• Mariculture has much scope for development
• Production efficiency is likely to be affected by
climate change