Traditional mussel culture depends on the natural environment for the provision of their feed, seed and space. The culture process is based on nature, depends on nature, and it also contributes to nature. A recent study showed the natural values of mussel culture plots, with more biomass and more biodiversity, being higher than natural mussel beds in the Dutch Wadden Sea. Despite or due to the maintenance and harvest activities of the farmers, mussel stocks on culture plots last longer than natural beds. It was concluded that mussel culture promotes nature conservation. Given the expected global population increase by 50 % in 2050, there is a strong need for improved food supply. Farming the ocean is a likely option. Aquaculture low in the food chain, without the provision of formulated feed, ie shellfish and seaweed should offer solutions. Given actual production trends in Europe, showing a decrease rather than a production increase, there is a clear need for an innovation agenda for all parties involved: producers, processors, governments, and stakeholders.

1. 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

2. GOALS OF THIS TALK
 What are characteristics of shellfish culture ?
 What makes it sustainable ?
 How can this be further developed ?
 Why is this relevant ?

3. • 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

4. 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

5. Suspended
culture
Pole culture
TRADITIONAL SHELLFISH CULTURE
• extensive : no additions
• depends on nature for feed, seed and space
• shellfish culture links to nature management

6. 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

7. LIFE CYCLE OF A MUSSEL
ADULT LARVAE
SPAT
SEED

8. CULTURE CYCLE - traditional
ADULT LARVAE
SPAT
SEED
SEED
FISHERY
HARVEST

9. CULTURE CYCLE - new
ADULT LARVAE
SPAT
SEED
SEED
FISHERY
HARVEST
SEED
COLLECTORS
HATCHERY

10. Seed Mussel Collector :
= Net or rope in the
water column
= Substrate for larvae

11. 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

12. 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

13. 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

14. 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

15. 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

16. 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

17. Impact
Control
Suction
dredge
Box core

18. 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

19. 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

20. 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 ?

21. Culture plot biomass
(red) >
Wild beds (green)
MUSSEL BIOMASS WILD BEDS / CULTURE PLOTS

22. 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

23. 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

24. 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

25. LEAFLET SHELLFISH FARMERS USA

26. 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

27. 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

28. 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

29. 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

30. FED VS NON FED AQUACULTURE (FAO, 2012)
Decrease in % non fed low food chain culture
Challenge for shellfish production

31. Duarte et al , 2007:
Rapid domestication of
marine species
in <100 years
FAO, 2012
Bivalve mollusc species
in culture > 70
PERSPECTIVE: DOMESTICATION

32. Analysis of culture perspectives
of valuable species for Europe
basis for diversification
Ranking,
Based on
- aquaculture
experience
- native
- price
- culture time

33. controlled production of spat:
= prerequisite for breeding and selection
= triploids, better growth, stronger shells and byssus threads,
low allergen shellfish, ...
PERSPECTIVE: HATCHERY / NURSERY SYSTEMS

34. Culinary biodiversity: fruit de mer > 15 species

35. Thank you