Transcript 11. Mariculture Pickering

Projected changes
to mariculture
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 D Pickering, Ben
Ponia, Cathy A Hair, Paul C Southgate, Elvira S
Poloczanska, Luc Della Patrona, Antoine Teitelbaum,
Chadag V Mohan, Michael J Phillips, Johann D Bell and
Sena De Silva
• Mariculture (marine
aquaculture) already
makes a significant
contribution to some
PICT economies
• It has unrealised
potential in other PICTs
• But future plans could
be de-railed by
projected climate
changes.
1. Current and projected
mariculture production in PICTs
Pearl
Marine shrimp
Seaweed (Kappaphycus)
Marine finfish
Batfish (P. orbicularis)
Barramundi
Grouper (Serranidae)
Edible Oysters
Mudcrab
Culture-based fisheries: Invertebrate re-stocking
Sea cucumber
Giant clam
Trochus
Green snail
Annual value of aquaculture in PICTs
• 2007 total value
US$ 211 million
• Pearl in French
Polynesia is
dominant
• Next is shrimp
in New
Caledonia
• These two
make up over
90% of total
value
Annual value of aquaculture commodity production
Livelihoods
Shrimp
Pearl
Contribution of aquaculture value
toward GDP
• Aquaculture
contributes
22% of
fisheries
contribution
to GDP in
PICTs
Annual percentage contribution of fisheries and aquaculture sectors to
Gross Domestic Product in PICTs
Projected production
without climate change
• Value of PICT aquaculture in 2007 it was USD
211 million (Ponia 2010)
• If no climate change, is “optimistically”*
forecast to be to be worth USD 320 million by
2025
* Though note recent SPC report ‘Opportunities for the Development of the Pacific
Islands Mariculture Sector‘
• Growth mainly driven by expansion within the
existing commodities, via adoption of these
proven commodities by additional PICTs.
2. Vulnerability of mariculture
Projected changes
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
• Mainly from lack of
knowledge about the
possible effects of
seawater acidification on
bone and shell formation
• Pearl aquaculture will be
more vulnerable to
acidification than shrimp.
• If projected changes in seawater pH adversely
affect pearl larvae, adult pearl shell, or pearl
quality, then this industry will be highly
vulnerable to climate change.
High-quality Fiji Pearls
Poor lustre, defects
Pearl
• The pearl industry is not
vulnerable to, and may
benefit from, other
projected changes in
climate such as sea level
rise, provided farm
structures do not become
too exposed to heavy seas.
• By 2100s seawater
temperature may become
problematic for larval
survival in some locations.
Hunter Pearls hatchery, Fiji Islands
Storm surge during Cyclone Tomas,
February 2010
Marine shrimp
• Pacific shrimp industries
face both benefits and risks
from climate change.
• Climatic conditions for
shrimp aquaculture in
higher latitudes are likely
to improve, subject to
seasonal temperature
instabilities in New
Caledonia not becoming
even more pronounced.
Now:
Future: good
Future: bad
Marine shrimp
The main threats to shrimp culture stem from:
• Acidification
• Sea level rise
• Scarcity of fishmeal
• Pathogens.
Marine shrimp
Now: crop in progress
• Inundation of lowlying coastal lands,
that make shrimp
ponds impossible to
drain dry, will have a
huge impact on the
New Caledonia
shrimp industry
Now: pond preparation
Future: poor pond prep.
Future: difficult to harvest
Kappaphycus seaweed
• Kappaphycus seaweed is
vulnerable to increased
seawater temperature
beyond 30oC
• Lower coastal salinity due to
higher rainfall can stress
seaweed
• These both cause “ice-ice”
and Epiphytic Filamentous
Algae (EFA) outbreaks
• Reduced nutrient upwelling
will slow seaweed growth
Ice-ice
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
• Due to higher
temperature, it is likely
there will be an increase
in the prevalence of
pathogens affecting
aquaculture commodities
in this region
• The nature and extent of
future aquatic animal
disease risks are not
clear.
White Spot Virus WSV
3. Key responses and adaptations
How should we respond?
• Expect production losses from extreme events
and ‘unexpected’ causes
• Ensure that financial planning for enterprises
can absorb such shocks
Photos: Cathy Hair
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
Source: Pickering et al. (2011)
How should we adapt?
Move shrimp ponds
landward or to higher
ground
Adopt more intensive
farming methods that
use less land and water
Source: Pickering et al. (2011)
How should we adapt?
• Build up walls and floors of existing shrimp ponds
Suitable sediment for
shrimp and meiofauna
Source: Pickering et al. (2011), 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
4. Outlook for mariculture
Pearl
• It will be impossible to
project production
changes for pearl until
more is known about
the likely effects of
seawater acidification
Shrimp
• Subject to adaptive strategies
being successful and costeffective, New Caledonia can
double its present size (i.e. to
4000 tonnes per annum and
1000 livelihoods)
• Fiji could develop to 1000 T in
the medium term
• PNG could develop to 2000 T
• But profit margins will be less
Kappaphycus seaweed
• Medium-term production
targets of around 1000
tonnes per year (engaging
several hundred
households) in each of Fiji,
Solomon Islands Kiribati and
Fiji should still be achievable
• But not in the same places,
by the same methods, or
with the same varieties in
current use.
Other commodities
• Marine finfish, mud crab,
corals, giant clam, trochus,
live rock and sea cucumber
are fledgling industries, so
projected change from
current production levels
will be small, however ...
• Loss of development
potential represents a
massive opportunity cost
for the region.
Conclusion
• Mariculture has
much scope for
development over
the next 40 years
and beyond
• But production
efficiency is likely
to be affected by
increased CO2
emissions
We need more
research on
the effects of
climate
change, and
on ways for
aquaculture to
be adapted to
the adverse
effects
Thank you