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SUSTAINABLE MUSSEL CULTURE:
Profitable for Planet and People
Aad Smaal,
Wageningen Universiteit and IMARES Yerseke
(Institute for Marine Resources and Ecosystem Studies)
Mussel Academy, June 3, 2014
GOALS OF THIS TALK
What are characteristics of shellfish culture ?
What makes it sustainable ?
How can this be further developed ?
Why is this relevant ?
• New institute 2006 • Part of Wageningen UR • 207 employees • Annual turnover € 26 Million
3 sites : = Yerseke 40 p = IJmuiden 87 P = Den Helder 80 p
IMARES YERSEKE
- location Yerseke 40 people
6 PhD’s, students
- > 50 Years shellfish research
- monitoring & assessment
- carrying capacity
- shellfish farming
- now including fish farming,
integrated culture and
coastal zone management Yerseke, centre of the
shellfish industry
Suspended culture
Pole culture
TRADITIONAL SHELLFISH CULTURE
• extensive : no additions
• depends on nature for feed, seed and space
• shellfish culture links to nature management
TRADITIONAL MUSSEL CULTURE NL:
Bottom culture since 1870
Based on
- new recruitment
- feed
- proper culture sites
i.e. based on nature
...and depending on nature
technical innovations
... but also on society: - other (new) stakeholders
- license to produce
management innovations
WADDEN SEA
LIFE CYCLE OF A MUSSEL
ADULT LARVAE
SPAT
SEED
CULTURE CYCLE - traditional
ADULT LARVAE
SPAT
SEED
SEED FISHERY
HARVEST
CULTURE CYCLE - new
ADULT LARVAE
SPAT
SEED
SEED FISHERY
HARVEST
SEED COLLECTORS
HATCHERY
Seed Mussel Collector : = Net or rope in the water column = Substrate for larvae
INNOVATION: SEED MUSSEL COLLECTORS (SMC)
Seed collection : since 2007 Increase from 2 to 15 mln kg Seed fishery : On average 2007-2012: 20 mln kg Largely variable 2010 and 2011 : 0 2012: 40 mln kg need: > 40 mln kg SMC = technical innovation
SMC harvest
Red = wild catch
Court decision: fishery may be harmful
Response of industry :
- Uncertainty: fishery policy promised
time for innovation till 2020
- Anger: negative impact was
not proven but suggested
- Public action: against the “green lies”
Response of NGO’s :
- It is the Ministry that was blamed by
the court for lack for clear policy
Response of Ministry :
- mediation agreement
DRIVER: CONFLICT DUE TO COURT DECISION 2008
Stop the green lies
Environmentalists not against mussel industry
AGREEMENT ON MUSSEL TRANSITION : 2009 - 2020
• No court cases
• Stepwise decrease of bottom seed fishery and development of SMC
• Closure of Wadden Sea areas for fishery
Oktober 2008 Agreement between stakeholders
• Mid term evaluation 2014
management innovation
Research framework
Traditional mussel culture depends
on mussel seed fished from wild beds
in the Wadden Sea
Mussel seed is fished on wild sublittoral beds
by bottom dredging after new spatfall in
autumn on unstable beds (green), and
next spring on relatively stable beds (red)
Fishery may disrupt benthic habitats including
their natural values
In case of doubt: no N2000 permit
Not only in NL, relevant for Europe
Research questions
Research approach
I – Seed fishery impact on natural values:
before – after, control – impact (BACI)
II - Comparison of natural values = biodiversity of:
● wild mussel beds
● mussel culture plots
● other sublittoral habitats in the western Wadden Sea
Sampling stations
western wadden sea: 40 * 2 * 4 ha plots Sampling inner 100*100 m Mussel spatfall driven distribution Sampling period 2006 - 2011
Closed Open
Impact
Control
Suction dredge
Box core
Mussel densities per plot : t0 / t1
1
2
0
Ref
2
0
Vis
2
2
0
Ref
2
0
Vis
Autumn fishery: t0=Before t1=After
control
impact
3
2
0
Ref
2
0
Vis
4
2
0
Ref
2
0
Vis
Spring fishery: Before After
Mussel biomass per plot over time excl spatfall
5
2
0
Ref
2
0
Vis
7
2
0
Ref
2
0
Vis
9
2
0
Ref
2
0
Vis
after 1 yr 3 yr 5 yr after spring fishery spring spring
control
impact
CONCLUSIONS FISHERY IMPACTS
Mussel biomass
Autumn fishery: decrease of mussel biomass, no significant
difference between fished and control plots
Spring fishery: significant difference,
lower biomass for 2 years after fishery on fished plots
After 3 years no difference impact and control sites:
wild mussel beds have limited longevity,
no dramatic fishery impact
What about mussels on culture plots ?
Culture plot biomass (red) > Wild beds (green)
MUSSEL BIOMASS WILD BEDS / CULTURE PLOTS
BIODIVERSITY WILD BEDS / CULTURE PLOTS
Survey on wild mussel beds, oyster beds, and mussel culture plots; 2008 – 2010: 568 stations in 3 yrs shellfish beds = biodiversity hot spots
All stations
Without M & O
M
O
Nr of species
Nr of samples
Species nr wild beds / culture plots
• Total 108 species in 159 box cores • 84 species on wild beds (5 unique) • 102 species on mussel culture plots (23 unique) • 16 species were invasive
and were all found in both habitats • Typical species:
wild: barnacles, sea anemones culture: ragworm, crab, starfish
CONCLUSION
Mussel beds are biodiversity hot spots
More mussels on culture plots
More biodiversity on culture plots
Wild beds sensitive to predation, better survival in low
salinity areas, with lower biodiversity
Fishery impact less dramatic than originally thought:
maintenance activity by the farmers enhances survival
Paves the way to combine exploitation and nature
conservation: Profit and Planet
LEAFLET SHELLFISH FARMERS USA
GOALS OF THIS TALK
√ What are characteristics of shellfish culture ?
nature based
√ What makes it sustainable ?
Profit and Planet
√ How can this be further developed ?
combine exploitation with other functions
Why is this relevant ?
People
FUTURE PRODUCTION
Global view:
● World population 1 ½ * (6 >> 9 mrd).
● Global welfare per capita : 5 *
● Pressure on earth: ~2 * lower
● Challenge : 1 ½ * 5 * 2 = 15 * so efficient
Seafood:
● Agrification of the oceans: blue growth
Challenge for Europe
PRODUCTION TRENDS
Asia + 5 % /yr Europe – 2 % / yr Compensated by price > European shellfish culture: • Tradition driven production • Small enterprises • Limiting factors
• Competing claims • Equal level playing field
PERSPECTIVES • Market pull • High-quality products • Low-food chain production
Duarte et al, 2009: Will oceans help feed humanity?
- Mariculture could be expanded to meet global demands
and should be based on low trophic level production
mussels, meat of the future
FED VS NON FED AQUACULTURE (FAO, 2012)
Decrease in % non fed low food chain culture
Challenge for shellfish production
Duarte et al , 2007: Rapid domestication of marine species in <100 years
FAO, 2012 Bivalve mollusc species in culture > 70
PERSPECTIVE: DOMESTICATION
Analysis of culture perspectives of valuable species for Europe basis for diversification
Ranking, Based on - aquaculture experience - native - price - culture time
controlled production of spat: = prerequisite for breeding and selection = triploids, better growth, stronger shells and byssus threads,
low allergen shellfish, ...
PERSPECTIVE: HATCHERY / NURSERY SYSTEMS
Culinary biodiversity: fruit de mer > 15 species
Thank you