Presentation is loading. Please wait.

Presentation is loading. Please wait.

Centre for Shellfish research Introduction, impact and management of the Pacific oyster Crassostrea gigas in Dutch coastal waters Aad Smaal, Karin Troost.

Published byCael Beecroft Modified over 9 years ago

Similar presentations

Presentation on theme: "Centre for Shellfish research Introduction, impact and management of the Pacific oyster Crassostrea gigas in Dutch coastal waters Aad Smaal, Karin Troost."— Presentation transcript:

1 Centre for Shellfish research Introduction, impact and management of the Pacific oyster Crassostrea gigas in Dutch coastal waters Aad Smaal, Karin Troost & Jeroen Wijsman Institute for Marine Resources and Ecosystem Studies

2 Flat Oyster (Ostrea edulis) culture since 1870 Problems with overstocking (1890), shell disease (1930), severe winters (1963) and Bonamia (1980) Introduction Pacific Oyster (Crassostrea gigas) in 1964 to restore oyster culture Pacific oyster culture:1550 ha bottomplots meanwhile proliferation: by (unexpected) reproduction in warm summers and larval dispersal INTRODUCTION C. gigas in the OOSTERSCHELDE

3 musselplots oysterplots Oosterschelde and Wadden Sea are main areas for shellfish bottom culture WAD OS

4 1980: 15 ha 1990: 210 ha 2002: 640 ha 2005: 800 ha OYSTER PROLIFERATION ON TIDAL FLATS: reconstruction on the basis of aerial photographs and ground truth

5 Centre for Shellfish research TOWARDS AN OYSTERSCHELDE ? OYSTER STOCK OOSTERSCHELDE 2000 - 2005 hamln kg kg/m2 oysterbed totalaliveflesh (ww) TIDAL FLATS80020025151 GULLIES700???? ROCKY SHORES100????

6 Centre for Shellfish research FURTHER PROLIFERATION 20 days

7 Centre for Shellfish research Biomass Surface N obs *10^6 kg Ha 2002:0.1 n.d.4 20030.15 n.d.4 2004: 11 40040 2005: 28 55087 OYSTERS WADDEN SEA 2005

8 North Sea Texel Sylt Eastern Wadden Sea Western Wadden Sea The Netherlands Germany Colonization of the German Wadden Sea - Sylt Oyster culture: 1986 - Proliferation from Dutch Wadden Sea 1998

9 Centre for Shellfish research BEFOREAFTER PACIFIC OYSTER INVASION : characteristics epifauna, reef builder, resistant, filter feeder

10 OTHER DOMINANT FILTER FEEDERS Cockle Native infauna, dynamic, resilient Mussel Native epifauna, forms bed structures, slow recovery, resistant

11 OTHER INVASIVE SHELLFISH SPECIES Slipper limpet 1930 Drilling mussel 1896Soft clam 1250 ? Razor clam 1978 Mainly infauna, No reef building

12 Centre for Shellfish research HYPOTHESIS Exotic species that are able to build resistant structures may change ecosystems more dramatically than resilient species As the oyster is typically a resistant species (eco-engineer) the introduction may induce a regime shift See: Smaal et al, 2005. IN: The Comparative Roles of Suspension-Feeders in Ecosystems, Dame RF Olenin S (Eds.) Kluwer Academic Publishers, Dordrecht.

13 Centre for Shellfish research IMPACT CONSEQUENCES - Food role in the- Shellfish culture - Recruitment ecosystem- Nature conservation - Space- Recreation

14 FOOD: competition Biomass Filtration capacity (5 – 25 l/h) Competition with other filter feeders: decrease of mussel growth 15 20 25 1990 199119921993199419951996 1997 19981999 2000 2001200220032004 Meat content of marketed mussels Oyster 32% Mussel 44 % Cockle 24 % days Carrying capacity problem: www.keyzones.com

15 RECRUITMENT: - gregarious settlement of oysters: positive feedback - filtration of (mussel) larvae: competition PhD project Karin Troost 0 1000 2000 3000 4000 5000 6000 oysterbedcontrol nr of larvae

16 SPACE: - Oysters settle on mussel and cockle beds - Oysters settle in subtidal areas including mussel culture plots - Oysters take over rocky shore fauna on average > 60 % coverage - Oysters form new habitat (reefs) on tidal flats

17 Centre for Shellfish research ECOSYSTEM ROLE OF OYSTER BEDS suspension feeding capacity: HIGH recruitment capacity: HIGH habitat type: epifauna or infauna: EPIFAUNA eco-engineering potential = substrate formation: POSITIVE FEEDBACKS = reef building: YES ability to form structures: HIGH RESISTANCE

18 Centre for Shellfish research REGIME SHIFT ? If oyster become dominant than changes in - species composition - food availability for waders - local geomorphology - habitat complexity - resilience - regime shift CONSEQUENSES ?

19 CONSEQUENSES for SHELLFISH CULTURE: - increased competition = production capacity change NATURE CONSERVATION: - less food for birds = carrying capacity change RECREATION: - health risk = multi-user conflict

20 WHAT TO DO? step 1 - Biomass reduction step 2 - Maintenance step 3 – Exploitation 2006: Experimental fishery 2 * 25 ha BACI oysters, sed, birds, mf 10 mln kg = 20.000 m3 100 shiploads

21 Centre for Shellfish research If you cant beat them, eat them

Download ppt "Centre for Shellfish research Introduction, impact and management of the Pacific oyster Crassostrea gigas in Dutch coastal waters Aad Smaal, Karin Troost."

Similar presentations

Pacific Oysters (Crassostrea gigas) in Strangford Lough, Northern Ireland Claire Guy and Dai Roberts The Queen’s University Belfast.

Pacific Oysters (Crassostrea gigas) in Strangford Lough, Northern Ireland Claire Guy and Dai Roberts The Queen’s University Belfast.
Centre for Shellfish Research SHELLFISH CULTURE AND NATURE CONSERVATION Aad Smaal Institute for Marine Resources and Ecosystem Studies Yerseke, NL.

Centre for Shellfish Research SHELLFISH CULTURE AND NATURE CONSERVATION Aad Smaal Institute for Marine Resources and Ecosystem Studies Yerseke, NL.
Lecture 20 Competition and Predation 1) Review: intertidal zonation 2) Causes of zonation -Physical and biological factors -Temperature and desiccation.

Lecture 20 Competition and Predation 1) Review: intertidal zonation 2) Causes of zonation -Physical and biological factors -Temperature and desiccation.
Lynn Ficarra. “an increase in the rate of supply of organic matter to an ecosystem.” (Nixon 1995) N & P land clearing, sewage, fertilizer, animals, fossil.

Lynn Ficarra. “an increase in the rate of supply of organic matter to an ecosystem.” (Nixon 1995) N & P land clearing, sewage, fertilizer, animals, fossil.
Water Use.

Water Use.
Esraa Elsayed Abou-Elmaaty Research Assistant at The National Institute of Oceanography and Fisheries Doing my masters on Venus clam biology in lake Timsah.

Esraa Elsayed Abou-Elmaaty Research Assistant at The National Institute of Oceanography and Fisheries Doing my masters on Venus clam biology in lake Timsah.
© 2006 Thomson-Brooks Cole Chapter 16 Continental Shelves and Neritic Zone.

© 2006 Thomson-Brooks Cole Chapter 16 Continental Shelves and Neritic Zone.
COASTAL ECOSYSTEM MANAGEMENT IN WELLFLEET HARBOR, MA: ADDRESSING SUSTAINABLE SHELLFISHING AND AQUACULTURE AnneMarie Cataldo, Earth, Environmental and Ocean.

COASTAL ECOSYSTEM MANAGEMENT IN WELLFLEET HARBOR, MA: ADDRESSING SUSTAINABLE SHELLFISHING AND AQUACULTURE AnneMarie Cataldo, Earth, Environmental and Ocean.
Life on the Continental Shelf

Life on the Continental Shelf
Chapter 8 Temperate Coastal Seas More than 90% of marine animals are benthic, living in close association with the seafloor, at the interface with the.

Chapter 8 Temperate Coastal Seas More than 90% of marine animals are benthic, living in close association with the seafloor, at the interface with the.
Food Webs in the Ocean Andrew W Trites Marine Mammal Research Unit University of British Columbia Who eats whom and how much?

Food Webs in the Ocean Andrew W Trites Marine Mammal Research Unit University of British Columbia Who eats whom and how much?
Museum Entrance Welcome to the Lobby History Eco- System Salinity Life- Cycle Museum of Oysters Visit the Curator Oysters.

Museum Entrance Welcome to the Lobby History Eco- System Salinity Life- Cycle Museum of Oysters Visit the Curator Oysters.
Class Bivalvia 1 Phylum Mollusca Class Bivalvia. 2 Defining characteristics – Two-valved shell – Body flattened laterally This class contains clams, oysters,

Class Bivalvia 1 Phylum Mollusca Class Bivalvia. 2 Defining characteristics – Two-valved shell – Body flattened laterally This class contains clams, oysters,
Intertidal Zones By. Ms. Messer. Intertidal Zone.

Intertidal Zones By. Ms. Messer. Intertidal Zone.
West Side Story the context, causes, and consequences of the Pacific oyster introduction to Washington State Jennifer Ruesink University of Washington.

West Side Story the context, causes, and consequences of the Pacific oyster introduction to Washington State Jennifer Ruesink University of Washington.
Oysters Addison Macaluso.

Oysters Addison Macaluso.
CHAPTER 15 Animals of the Benthic Environment

CHAPTER 15 Animals of the Benthic Environment
Garden of the Salish Sea What country is that? U.S.A.? Canada? Hey it’s both!

Garden of the Salish Sea What country is that? U.S.A.? Canada? Hey it’s both!
Printing: This poster is 48” wide by 36” high. It’s designed to be printed on a large-format printer. Customizing the Content: The placeholders in this.

Printing: This poster is 48” wide by 36” high. It’s designed to be printed on a large-format printer. Customizing the Content: The placeholders in this.
Marilyn Latta Eden Landing Working Group October 27, 2009 Subtidal Habitat Update Eden Landing Living Shoreline Project Ideas.

Marilyn Latta Eden Landing Working Group October 27, 2009 Subtidal Habitat Update Eden Landing Living Shoreline Project Ideas.

Similar presentations

Ads by Google