Intertek Moody Marine

INTERTEK MOODY MARINE

Date: August 2012

Ref: 82140

Dutch Oyster Association Oyster Fishery

Public Comment Draft Report

Authors: A Hough, A Brand, Z Jager

Jaap de Rooij Dutch Oyster Association Postbus 124 4400 AC Yerseke Netherlands Tel: +32 50674822 [email protected]

Intertek Moody Marine Merlin House Stanier Way Wyvern Business Park Derby United Kingdom DE21 6BF

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Contents

Contents ...... 2 1. Executive Summary ...... 3 2. Authorship and Peer Reviewers ...... 5 3. Description of the Fishery ...... 6 4. Evaluation Procedure ...... 34 5 Traceability ...... 37 6 Evaluation Results ...... 37 References ...... 41 Appendices ...... 45 Appendix 1 Scoring and Rationales ...... 45 Appendix 1.1 Performance Indicator Scores and Rationale ...... 45 Appendix 1.2 Risk Based Framework (RBF) Outputs ...... 89 Appendix 1.3 Conditions ...... 97 Appendix 2. Peer Review Reports ...... 98 Appendix 3. Stakeholder submissions ...... 119 Appendix 4. Surveillance Frequency ...... 120 Appendix 5. Client Agreement ...... 121 Appendix 5.1 Objections Process ...... 122

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1. Executive Summary

This assessment is of two species of oyster, the native flat oyster (Ostrea edulis) and Pacific oyster (Crassostrea gigas). Both species are fished in two adjacent waterbodies in Southern Holland, the Oosterschelde and Lake Grevelingen. As discussed below, the native oyster has been decimated by the disease bonamiosis while the Pacific oyster has thrived.

The fishery in both waterbodies is based on an area of cultivated plots, with each plot assigned to a licenced fisherman to manage. In Grevelingen, plots are managed to encourage native oyster (a more valuable species), but Pacific oyster may also be taken. In Oosterschelde, native oyster are very rare and so fishing is mostly of gigas; some native oyster may be taken. In both waterbodies, the provision of suitable substrate for settlement of native oyster, and harvest before animals are susceptible to bonamia, serves to preserve the native stock.

The assessment therefore includes both species in both waterbodies (Oosterschelde and Grevelingen). It is noted that there are also imports and exports of oyster carried out by companies based in Yerseke (the base of the oyster fishing fleet). As these do not overlap with the fisheries under assessment, these are not considered further here. As there are two species targeted, and two areas (Oosterschelde and lake Grevelingen), there are four separate Units of Certification (UoC), although these are being assessed at the same time.

The assessment was carried out by a team of three specialists; Dr Andrew Hough PhD. Lead auditor contracted from Hough Associates, Dr Andrew Brand, PhD. Retired university lecturer and Dr Ir Zwanette Jager, PhD. Consultant. Andrew Hough is fully trained in use of the MSC Risk-Based Framework. The draft report was peer-reviewed by a further two specialists, Andy Read and Dr Terry Holt.

Information gathering was carried out principally during a visit to Yerseke, the main port for the oyster fleet. Itinerary and meetings were as follows: 13 March 2012. Site visit in Yerseke, Netherlands. Interviews and discussions on fishery with: J de Rooy, Secretary, NOV B Keus, Advisor NOV J Dingemanse, Member, NOV K Troost, IMARES M Poelman IMARES G-J van Veen, Fishery Inspector, AID 14 March 2012. Yerseke a.m. Observation of fishing activity on board NOV member vessel YE 60 in Kom, Oosterschelde. Aart Cornelisse Skipper. p.m. SICA Workshop at offices of IMARES, Yerseke. Attending: B Keus, Advisor, NOV K Troost, IMARES A Smaal, IMARES

Fishing on the free grounds, using an oyster dredge. In the fishery on the free grounds, both spat and grown oysters are retained, other by-catch is returned to the water through an on-board flushing system. This activity occurs in Oosterschelde, not in Grevelingen, and the fishermen need a fishery licence and an Nb-(nature conservation act) permit. The spat and grown oysters are then transferred to the culture plots in Oosterschelde for growing on and harvesting in time with market demands. It is

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not allowed to transfer shellfish from Oosterschelde to Grevelingen. Fishing on the free grounds is not allowed in the intertidal areas, except in the Kom (which is given over to oyster plots), nor inside areas closed for other purposes (nature conservation, mussel culture etc) as indicated on Hydrographical Map 1805 (edition 2011).

Growing oysters on the culture plots in Oosterschelde and Grevelingen. The culture plots cover a total area of 1500 ha in Oosterschelde and of 550 ha in Grevelingen. The Oosterschelde culture plots are all concentrated in the shallow eastern part, which is called “Kom van de Oosterschelde” or the Kom. The culture plots in Lake Grevelingen are in designated areas, situated around Hompelvoet, Veermansplaat and alongside the former tidal channels at water depths between 1-5 m. The flat oyster is mainly cultivated in Grevelingen, not in Oosterschelde (Troost 2009).

The growing of Pacific oysters on culture plots in the Oosterschelde involves manipulation by the fishermen: oysters are repeatedly fished on the plots, using the oyster dredge. The fishermen sort the oysters to different size classes on board of the vessel and redistribute the oysters over their plots. As a side effect of this repeated handling, the oyster shells get more rounded and thicker, which improves their commercial value. Oyster spat is collected on the plots by providing suitable settling substratum (empty shells). Spat and small oyster may also be introduced onto plots from fishing on the free grounds; however, the number of Pacific oyster (C gigas) in both water bodies is extremely large, recruitment is high and the management of plots is more an issue of providing oyster of the right size at the right time, rather than securing stock. The flat oyster (cultivated in Lake Grevelingen) is more fragile and is disturbed as little as possible.

The scores for the MSC Principles for the Native Oyster Ostrea edulis unit of certification in Lake Grevelingen were: Final Principle Scores Principle Score Principle 1 – Target Species 90.0 Principle 2 - Ecosystem 85.3 Principle 3 – Management System 89.9

All other units of certification scored: Final Principle Scores Principle Score Principle 1 – Target Species 83.5 Principle 2 - Ecosystem 85.3 Principle 3 – Management System 89.9 The recommendation of the assessment team is therefore that all units of certification be certified.

One Condition of Certification was raised for PI 2.2.2, management of bycatch species; The SG80 requirements for this PI are only partially met as there is not ‘qualitative information and some quantitative information available on the amount of main bycatch species affected by the fishery, nor does sufficient data continue to be collected to detect any increase in risk to main bycatch species (e.g., due to changes in the outcome indicator scores or the operation of the fishery or the effectively of the strategy)’.

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2. Authorship and Peer Reviewers

Assessment Team:

Dr Andrew Hough PhD. Lead auditor contracted from Hough Associates.

Dr Andrew Brand, PhD. Retired university lecturer.

Dr Ir Zwanette Jager, PhD. Consultant.

Andrew Hough is fully trained in use of the MSC Risk-Based Framework.

Peer Reviewers:

1. Andy Read. Andy Read is currently Director of Fisheries in the Isle of Man. A week after graduating with a degree in marine biology he started out as a ‘deckie learner’ in the Isle of Man scallop fleet, before working in Australia and Scotland on larger vessels, and eventually owning his own potting vessel. After 8 years at sea he took a Masters degree in Fisheries Science at Aberdeen University, and following a brief spell in Washington DC working on fisheries policy, took up a post as Assistant Chief Executive of the National Federation of Fishermen’s Organisations, based in Grimsby. He remained in Grimsby as secretary of a large Fish Producer’s Organisation, the North Sea Fishermen’s Organisation, for a further 5 years, before returning to the Isle of Man. During the 5 years with the NSFO he also worked as a consultant on a number of fisheries projects, including ones for the European Parliament Fisheries Committee, European Commission, Government of Malta and a variety of offshore energy developers. As Director of Fisheries in the Isle of Man, Andy Read has overseen a large number of changes within the industry, developing a conservation regime, underpinned by scientific advice that has seen the Isle of Man Queen Scallop fishery successfully apply for MSC accreditation. He has also worked on shellfish MSC assessments in the Netherlands.

2. Terry Holt. Dr. Holt is a director of CMACS Ltd with responsibility for managing marine consultancy projects, Environmental Assessments and ecological surveys. He has over thirty years experience in shellfish ecology, marine aquaculture, EIAs and benthic fish and invertebrate surveys, including providing expert evidence on molluscan fisheries at planning enquiries. Dr Holt has previously been involved in Marine Stewardship Council (MSC) preassessments, main assessments and annual surveillance audits for Intertek Moody Marine and other companies, (Burry Inlet Cockle fishery, Danish Blue shell mussel fishery Limfjord, Ben Tre clam fishery Vietnam, Patagonian Toothfish, Kerguelen and Crozet Toothfish, Blackwater Oyster Fishery; Canadian east coast scallops and Isle of Man Queen Scallop Fishery) and has worked on molluscan fishery pre-assessments for other organisations in SE Asia. He also contributed at early MSC workshops on the development of generic scoring guidelines and refining of assessment methods.

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3. Description of the Fishery

3.1 Unit(s) of Certification and scope of certification sought

This assessment is of two species of oyster, the native or flat oyster (Ostrea edulis) and Pacific oyster (Crassostrea gigas). Both species are fished in two adjacent waterbodies in Southern Holland, the Oosterschelde and Lake Grevelingen. As discussed below, the native oyster has been decimated by the disease bonamiosis while the Pacific oyster has thrived.

The assessment therefore includes both species in both waterbodies (Oosterschelde and Grevelingen).

It is noted that there are also imports and exports of oyster carried out by companies based in Yerseke (the base of the oyster fishing fleet). As these do not overlap with the fisheries under assessment, these are not considered further here.

As there are two species targeted, and two areas (Oosterschelde and lake Grevelingen), there are four separate Units of Certification (UoC), although these will be assessed at the same time.

UoC 1 Species: Pacific Oyster Crassostrea gigas Gear: Oyster dredge Area: Oosterschelde (Eastern Scheldt) Management: Dutch Oyster Association (NOV) Client Group: Members of Dutch Oyster Association

UoC 2 Species: Pacific Oyster Crassostrea gigas Gear: Oyster dredge Area: Lake Grevelingen (Grevelingenmeer) Management: Dutch Oyster Association (NOV) Client Group: Members of Dutch Oyster Association

UoC 3 Species: Native Oyster Ostrea edulis Gear: Oyster dredge Area: Lake Grevelingen (Grevelingenmeer) Management: Dutch Oyster Association (NOV) Client Group: Members of Dutch Oyster Association

UoC 4 Species: Native Oyster Ostrea edulis Gear: Oyster dredge

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Area: Oosterschelde Management: Dutch Oyster Association (NOV) Client Group: Members of Dutch Oyster Association

The client group is all members of the Dutch Oyster Association (NOV). This includes all eligible fishers. The fisheries are all within scope of the MSC standard – see below.

3.1.1 Scope of Assessment in Relation to Enhanced Fisheries

Both fisheries rely on enhancement of oyster stocks – a Catch and Grow (CAG) system. A1. Young oysters are collected from natural spatfall A2. The native oyster is native. Pacific oyster is an introduced species (see below). A3. The stock reproduces naturally A4. This is not a HAC system B1. No artificial feeding takes place B2. No disease prevention chemicals etc are used C1. Habitat modifications are reversible and do not cause serious harm to ecosystem structure and function

3.1.2 Scope of Assessment in Relation to Introduced Species Based Fisheries (ISBF)

For Pacific oyster, this is within scope as an Introduced species: A. It has a larger population size than the native oyster; the species has extended its range; the species cannot be eradicated B. The species was introduced prior to 1993 C. There are no continuing introductions to the area

3.2 Overview and History of the fishery

The native (or flat) oyster Ostrea edulis is the native species in the Netherlands, but has never been very abundant. Flat oysters have always been considered a scarce and expensive delicacy. Oyster fishing has been practised in the Netherlands for at least two centuries. Before 1860 all oysters harvested in the Netherlands came from wild oyster banks in Zeeland and at the Wadden Sea. At that time, in France wild oyster banks started to overgrow each other and a method of oyster farming with "collecteurs" was developed. Collecteurs are substrates for young oysters (spat) to settle on. Collecteurs were used to keep oysters in correct (not too high) densities in sufficiently fertile water in order to guarantee good growth. Examples of collecteurs are roof tiles and oyster or mussel shells.

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In 1870 in the Netherlands province of Zeeland this method of oyster farming was introduced together with a system of ownership of oyster fields (oesterpercelen). Due to the developing oyster industry, the village of Yerseke experienced a growth from 770 inhabitants in 1849 to 4 469 in 1885. With ups and downs the oyster industry maintained itself well until in 1963 almost the entire flat oyster population was wiped out due to the severe winter. Around 160 oyster farmers stopped their activity in the next year, also because it was decided to close the Oosterschelde dam. The feared consequence of this closure was the transformation of the Oosterschelde into a freshwater body in which oyster farming was impossible. On top of this, the flat oyster was hit by bonamiosis disease in 1980 and from this the flat oyster stock has never recovered. Flat oysters can still be found in limited numbers, mostly in Grevelingen, but production has been decimated.

Although the flat oyster is scarce and hard to get to the market size (because of the high mortality of the flat oysters due to the continuing presence of Bonamia ostreae, the organism that causes bonamiosis), farming the flat oyster is still economically viable because of its high price. Recently oyster farmers have started a project to develop "Bonamia free oyster farming".

In the early 1960s the Pacific oyster invaded the seashores of France and Belgium. By 1963 Pacific oysters were found in the harbour of Oostende, a few tens of kilometres from the Dutch border. In 1964 the Pacific oyster was introduced in the Netherlands by oyster farmers to compensate for the loss of the flat oysters in the severe 1963 winter. Initially it was believed that the Pacific oyster would not be able to reproduce in the colder waters of the Netherlands, and that the Oosterschelde would

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eventually turn into a freshwater system. However, this was a misjudgement (and the Oosterschelde remains a marine ecosystem) and the Pacific oyster gradually spread to all coastal waters of the Netherlands. Nowadays, the bulk of the Dutch oyster harvest consists of the Pacific oyster.

In 1986 the Oosterschelde was cut-off from the sea by the permeable Oosterschelde dam. To maintain the marine environment in the Oosterschelde the original design had been modified in such a way that restricted tidal access is allowed. But the tidal flow, and hence the difference between low and high tides, was reduced. This reduction in water flow means that the once fast flowing deep channels are getting shallower which causes the shallow intertidal flats to suffer from erosion (in Dutch this phenomenon is called "zandhonger", meaning hunger for sand). In this way yearly around 50 ha of intertidal flats disappear under the water surface. Oysters banks make the plates resistant to erosion. This makes the increase of the Pacific oyster in the Oosterschelde even more pronounced: while banks with mussels or other shellfish tend to decrease in surface area, oyster banks remain.

Being an enhanced fishery, the management of the fisheries is the responsibility of the Dutch Oyster Association. The Directorate General for Public Works and Water Management is responsible for management of water bodies.

There is no TAC as this is an enhanced fishery. In 2010 there was a production of about 35,000,000 Pacific Oysters and about 700,000 Native Oysters (note that in this fishery production and landings statistics are always recorded as numbers of oysters and never as weight). This is a typical annual production.

The fishery consists of two separate activities (see “Visplan 2012” of the Dutch Oyster Association):

1. Fishing on the free grounds, using an oyster dredge. In the fishery on the free grounds, both spat and grown oysters are retained, other by-catch is returned to the water through an on-board flushing system. This activity occurs in Oosterschelde, not in Grevelingen, and the fishermen need a fishery licence and an Nb-(nature conservation act) permit. The spat and grown oysters are then transferred to the culture plots in Oosterschelde for growing on and harvesting in time with market demands. It is not allowed to transfer shellfish from Oosterschelde to Grevelingen. Fishing on the free grounds is not allowed in the intertidal areas, except in the Kom (which is given over to oyster plots), nor inside areas closed for other purposes (nature conservation, mussel culture etc) as indicated on Hydrographical Map 1805 (edition 2011).

2. Growing oysters on the culture plots in Oosterschelde and Grevelingen. The culture plots cover a total area of 1500 ha in Oosterschelde and of 550 ha in Grevelingen. The Oosterschelde culture plots are all concentrated in the shallow eastern part, which is called “Kom van de Oosterschelde” or the Kom. The culture plots in Lake Grevelingen are in designated areas, situated around Hompelvoet, Veermansplaat and alongside the former tidal channels at water depths between 1-5 m. The flat oyster is mainly cultivated in Grevelingen, not in Oosterschelde (Troost 2009).

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Figure 1. Map of Oosterschelde (top panel) and Grevelingen (bottom panel) with the locations of the oyster culture plots indicated in brown (top panel) and pink (bottom panel). Source: RWS.

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3.3 Principle One: Target Species Background

3.3.1 Biology of the target species

Ostrea edulis

There is an enormous literature on the European flat or native oyster, Ostrea edulis, Linnaeus, 1758. Ostrea edulis is a bivalve mollusc with a wide geographical range which extends from latitude 65°N in Norway, along the west coast of Europe as far as the Iberian Peninsula, and further south along the Atlantic coast of Morocco. It extends into the Mediterranean, primarily along the north coast and penetrates into the Black Sea as far as the Crimea (Alcaraz & Domingues 1985). Natural populations of native oysters formerly fringed much of this range (Yonge 1960). Although some beds remained in various regions, including Grevelingen in the Netherlands, wild oyster populations had become scarce around Europe by the 1940s. As a result, the European flat oyster industry became based mainly on aquaculture, though some native oysters have continued to be produced by dredging from wild stocks (Kennedy & Roberts, 1999). In many cases, as in the Netherlands, these wild stocks have often been augmented at various times by the re-laying of large numbers of spat brought in from elsewhere. The likely consequences of this will have been a genetic homogenization, masking any naturally evolved geographic differentiation (Saavedra et al., 1993).

Native oysters can be found intertidally but generally occur offshore from about low water down to some 80 m on firm, comparatively immobile bottoms of mud, rocks, muddy sand, muddy gravel with shells, hard silt or old peat bottoms (Tebble 1966), but the main concentrations are usually in shallower water, down to some 20 m. They are sessile animals, cementing to hard objects on the seabed by the left (lower) shell, so the substrate must contain suitable, clean, hard surfaces for settlement (known as cultch).

In appearance, O. edulis is usually roughly circular in shape, but the shell is often distorted, conforming to the shape of the surface to which it is attached. The irregular shell has a distinct hooked beak, patterned with delicate foliation. The two halves (valves) of the shell are of different shapes. The left valve is concave and fixed to the substratum, while the right valve is flat with rougher edges and sits inside the left. The valves are held together at one end by an elastic ligament. Oysters are monomyarian bivalves (Yonge, 1960), with only one large adductor muscle after settlement, with its centre to the posterior of the midline: this serves to close the valves against the pull of the ligament. If left unfished, the native oyster often grows to 10-12 cm shell length but occasional very large specimens have been reported up to some 20 cm (Orton & Amirthalingam 1930) and these very large oysters can live for over 20 years.

Both the planktonic larvae and adult oysters are filter feeders, extracting particles from the water by means of ciliary mechanism that sort particles and pass them to the mouth. In the larval stages, small organic particles and micro-organisms are collected around the base of the velum but only the most minute can enter the very small mouth (Yonge, 1960). At this stage micro-flagellates make up a most important part of the diet. After settlement, spat and adult oysters live in an environment on the seabed where they are exposed to, and have mechanism to deal with, larger concentrations of particulate organic matter in the water. Ciliary mechanism on the gills, labial palps and in the stomach, pump water, and filter and sort particles so that the smallest particles are available for intracellular digestion. The diet now includes organic detritus, bacteria, diatoms, dinoflagellates and a variety of protozoans, together with the smallest planktonic crustaceans and fragments of larger animals. However, it is not clear to what extent these larger particles are utilized, as there is little evidence of extracellular digestion in Ostrea edulis (Yonge, 1946,1960), though this has been shown

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to occur in some other bivalve species (Davenport et al. 2000). Oysters have mechanisms to deal with increased turbidity, but high concentrations of suspended particles, even though edible, often prevent efficient feeding by forcing the oyster to close the shell and stop feeding or to incur the high metabolic cost of pseudofaeces production.

Ostrea edulis is a protandric sequential hermaphrodite: the young oyster first becomes sexually mature as a male, then changes relatively slowly to a functional female, after which it very quickly becomes a male again and so on alternately throughout life (Spärck, 1925; Orton 1937). The change from female to male takes place very quickly, being completed within a few days of the eggs being discharged (Yonge, 1960). The change from male to functional female is much slower as the formation of eggs makes greater metabolic demands to provide the yolk needed for the initial development of the larvae. The speed and frequency with which the oysters change sex depends upon the feeding and temperature conditions. There is a general pattern throughout the latitudinal range of the species. At the northern end of the range in Scandinavia and the Netherlands oysters generally change sexes only once a year, functioning in alternate years first as males, then as females (Korringa, 1957). At the latitude of the UK they may function as both sexes in the same year, with some individuals at favourable locations spawning twice as females, with intervening activity as males, in the same summer. Finally, at the southern end of the range in the warmer waters of the Biscay coast of France or in the Mediterranean, oysters may alternate between being a functional male and a functional female several times in the same season. The age of first sexual maturity varies with temperature but is usually 3-4 years old in the UK and in the Netherlands (Orton 1927; Cole 1941, Korringa, 1957 although functional males have been recorded at one year of age after exceptionally warm years (Orton 1922; Dodd et al. 1937).

Spawning takes place in the summer months, when the temperature reaches about 15°C. The eggs and sperm are discharged from the gonad into the chamber above the gills. For male oysters the sperm is immediately pumped out in the exhalent water current. For the females, however, the eggs are forced against the water current through the fine channels in the gills into the inhalant chamber, where they are fertilized by sperm brought in with the inhalant water current. Successful fertilization is enhanced by synchronised spawning between individuals: when one oyster spawns it stimulates others nearby to start spawning. In all Ostrea species (but not in Crassostrea) the fertilized eggs are retained in the inhalant chamber for a period of incubation, covering the gills, viscera and mantle while they undergo their initial development. After 7-15 days, depending on temperature, they have developed into veliger larvae capable of swimming and feeding in the plankton, and are ready for release, a process known as swarming. This involves the shell opening widely and ejecting a cloud of larvae through the inhalant siphon by rapid contraction of the adductor muscle closing the shell. This process is repeated several times at irregular intervals over a period of several hours, until all the larvae are ejected. Ostrea eggs are fairly large (about 0.15mm diameter) because yolk reserves are needed by the larvae during the period of incubation. Despite this, the fecundity is still very high (though not nearly as high as the Crassostrea oysters that do not incubate the larvae), with 1-2 million larvae incubated at one spawning (Walne 1964), and one individual may spawn more than once a year in warm waters.

The planktonic veliger larvae swim and feed for a period of 7-20 days, depending on temperature. During this time the structure of the larvae become more complex with the development of the umbo, larval shell, foot and byssus gland, together with sense organs to detect light and gravity. When the ciliated velum is withdrawn the larvae sink to the bottom and can crawl around on the recently developed foot, seeking a suitable hard surface for settlement. At this time the larvae can withdraw the foot, extend the velum and resume swimming, and can do this a number of times before undertaking the irreversible processes of final settlement. Site selection involves various sense organs, and larvae tend to settle away from the surface and in shady places on the under surfaces of objects (Korringa 1940). Settlement is also gregarious, with larvae settling more readily on surfaces to which

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others are attached (Cole & Knight-Jones 1939). This is a chemosensory response that tends to aggregate populations into patches, an adaptation that aids fertilization success in a sessile species.

When a suitable site is selected, the contents of the byssal gland are squeezed out onto the surface of the substrate and the larva pushes the left shell valve into the drop of byssal cement, which sets rapidly in contact with seawater. The oyster is then firmly fixed in that position; if it becomes detached, it is incapable of reattaching or of any form of locomotion for the rest of its life – a factor utilized in hatchery cultivation to provide cultchless spat.

Settlement is followed by a rapid metamorphosis that involves the loss of those structures concerned with swimming and crawling (e.g. the velum, foot and eyes) and the body takes on the adult form with the elaboration of structures, like the gills and shell, required for a sessile way of life. There is a rapid marginal extension of the shell, which widens the area of attachment of the left valve to the surface as it grows, and the shell form becomes flatter, which reduces resistance to water movements. Subsequent growth in juvenile and adult oysters depends on various environmental factors such as temperature, food supply and exposure, and after sexual maturity on the metabolic demands of spawning. Shell growth in oysters is added in the form of “shoots”, which are periodic rapid paper- thin marginal extensions of the shell, which then thicken and harden over a period of a few weeks. This form of growth results in the characteristic series of wavy ridges that cover the shell surface in concentric rings.

As with all high fecundity invertebrates, the mortality of the planktonic larvae and newly settled juveniles is enormous. Korringa (1941) estimated that only about 250 larvae out of every million O. edulis larvae survived to become spat in the Oosterschelde. Of these, 95% died before winter. Annual variations in the numbers of eggs released, fertilization success, and larval and spat mortality all contribute to large annual variations in recruitment. In general, warm summers often prove to be good years for oyster settlement and survival. Despite the high fecundity, the recovery of depleted populations is often a slow process (Spärck, 1951).

After settlement, spat and adult oysters are exposed to numerous physical hazards, predators, parasites and diseases that cause mortality. They also have to contend with animals that compete with them for space, or food. Exceptionally hot summers or very severe winters have occasionally caused mass mortalities in shallow-water European populations, as occurred in the Netherlands in 1963. While able to tolerate salinities down to about 23 ppt, flat oysters are not able to survive prolonged exposure at lower salinities, so are vulnerable to major floods and melting ice and snow. Burial under mobile sediments and exposure to anoxic water are also occasional causes of heavy mortalities.

Oysters have numerous invertebrate predators and are also eaten by some fish. In general, the thin- shelled spat are the most vulnerable and predation declines as the oysters becomes larger and the shell thickens. Various crabs, but notably the common shore crab Carcinus maenas, and the common starfish Asterias rubens, are serious predators in many fisheries (Hancock, 1955). In many European oyster populations the most serious predators are the gastropod molluscs, known as oyster drills. These highly specialised predators are able to drill through the shell, using the radula aided by acid secretion. There are two important species of drill, the native rough tingle, Ocenebra erinacea, and the introduced American whelk tingle, Urosalpinx cinereraria, but the common whelk, Buccinum undatum, and the dogwhelk, Nucella lapillus also occasionally eat oysters (Yonge, 1960). Although common around the British Isles, Ocenebra erinacea was not thought to occur in more northerly populations, because of its susceptibility to cold (Mistakidis & Hancock 1955; Crisp, 1964), until it was reported in surveys of the Oosterschelde, Netherlands (Faasse & Ligheart, 2007) and in Limfjord, Denmark (Jensen & Hoffman, 2007). However, both of these populations have subsequently been found to be the very similar looking Japanese oyster drill, Ocinebrellum inornatus, a native of the North Pacific that has been unintentionally transferred to Europe, via North America, with shipments

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of the Pacific oyster Crassostrea gigas (Lützen et al. 2011). While Crassostrea gigas is its principal food in the North Pacific, it has taken readily to feeding on Ostrea edulis in Europe.

Many animals, like ascidians and barnacles, compete with Ostrea edulis for space, or food, but perhaps the most important in the Netherlands is the Pacific oyster, Crassostrea gigas. These were widely introduced into Europe as a cultivated species in the 1960s but have subsequently naturalized and are now spawning and settling in many areas including Oosterschelde and Lake Grevelingen. Compared with Ostrea edulis, C.gigas is a more efficient filter-feeder and has a higher growth rate then O. edulis (Mann 1979) and appears to be generally competitively superior.

Another important competitor in many areas is the slipper limpet, Crepidula fornicata. This species was introduced into the UK with imported oysters from North America in about 1880 and has subsequently spread throughout Europe where it can occur in such high densities that it causes problems for oyster cultivation. Although it has been reported to be present in the Netherland since about 1926 (Blanchard, 1997), and increase rapidly in Grevelingen to make up half the macrobenthic biomass by 1988 (Nienhuis, 1992), it does not appear to have caused problems for the oyster cultivation and the population now appears now to be declining in Grevelingen (A Comelisse, Boat skipper Pers com.).

Various invertebrate and fungal parasites affect the body and shell of oysters, resulting in reduced growth, loss of condition or death. Probably the most important are a number of protozoan parasites that have caused mass mortalities. In 1920/1, the minute flagellate protozoan Hexamita reduced stocks of Ostrea edulis on both cultivated and natural beds in England, France, Holland, Germany and Denmark to such low levels that many never recovered (Yonge, 1960). More recently, first Marteilia refringens in the 1960s (Balouet & Chastel 1979), followed by Bonamia ostreae in the 1970s, spread across Europe causing major mortalities and loss of production (McArdle et al. 1991). Bonamia was introduced into the Netherlands with oysters (O.edulis) from Brittany in 1980. It caused the nearly complete disappearance of Dutch culture of O. edulis and is still infecting oysters in the Oosterschelde estuary and Lake Grevelingen (Van Banning 1991; Wolff 2005). Culture of native oysters in many areas of Europe is now dictated by measures to counter Bonamia ostreae by reducing densities and taking other actions to reduce infestation levels (Hugh-Jones 1994). The threat of Bonamia has driven many European oyster growers to cultivate the Pacific oyster, which is not susceptible to bonamiosis and has a faster growth rate than O. edulis (Kennedy & Roberts, 1999).

Crassostrea gigas The Pacific oyster (also known as the Japanese or cupped oyster), Crassostrea gigas (Thunberg, 1793), originates from the Sea of Japan but was introduced for cultivation into the USA and Canada in the early 1900s and into Europe much later, in the mid-1960s. Oyster growers first introduced C.gigas into the Dutch Oosterschelde estuary in 1964 (Drinkwaard 1999a, 1999b) and they then spread rapidly throughout all Dutch estuaries (Bruins 1983; Drinkwaard 1999b; Wolff and Reise 2002; Smaal et al. 2005; Dankers et al. 2006) aided by numerous consignments of different genetic strains from British Columbia, Japan and elsewhere.

Many aspects of the biology of Crassostrea gigas are similar to Ostrea edulis but there are a number of important differences. While shell shape can be very variable, depending on the nature of the seabed and the degree of crowding, C. gigas is more deeply cupped, is often elongated and can grow to a larger size (30cm). The shell surface is sculpted with large, irregular, radial folds with overlapping, concentric lamellae in mature specimens, often with extensive fluting.

The two species occupy a similar ecological niche but C. gigas has much broader environmental tolerances. Ostrea edulis has a low temperature tolerance of about -1.5°C and suffered mass mortality in Oosterschelde during the severe winter of 1962/3, with numbers falling from 120M to 4M

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(Drinkvaard, 1999; Smaal et al 2009). As a result, very large numbers of C. gigas were imported from 1964 onwards as this species has a low temperature tolerance of -5°C, and can resist temperatures as low as -17°C (Troost, 2009). Similarly, the salinity tolerance range of C. gigas is much greater at 10- 42 psu, compared with 25-34psu for O.edulis. In the Netherlands, C. gigas is almost exclusively found in estuaries and the coastal Wadden Sea, whereas O. edulis was found in more marine salinities, and was common in the North Sea (e.g. the 'oestergronden' north of the Wadden Sea islands; Olsen 1883) but is now only common in Lake Grevelingen. C. gigas tends to settle in the same locations and at the same tidal level as Mytilus edulis resulting in the overgrowth of mussel beds (Nehls et al 2006) but they themselves can form substrate for mussels (Fey et al 2010) However, C. gigas is a universal ecosystem transformer taking over vast areas of suitable substrate and constructing reef structures.

The reproductive biology of Crassostrea gigas also differs considerably from Ostrea edulis. Whereas the native oyster, like all species of the genus Ostrea, are larviparous and brood the larvae in the mantle cavity for a period before release, Crassostrea oysters are oviparous and the eggs and sperm are released immediately on spawning so fertilization takes place outside the shell. Fecundity is much higher, at 50-120 million for C. gigas compared with 1-2 million in O.edulis. In the Netherlands, C. gigas needs a period of 4-8 weeks with temperatures >18°C before spawning, which usually occurs in July and August, and the larval period is 3-4 weeks depending on temperature. First sexual maturity occurs in summer one year after settlement. C. gigas, like O. edulis, is a sequential hermaphrodite, maturing first as a male then turning into a female and retaining the ability to change sex throughout life (Reise, 1998).

Crassostrea gigas is less predated and infected by diseases and parasites than O. edulis (Troost, 2009). In Dutch waters C. gigas has some parasites that came with it from the north-west Pacific, and is also infected by European parasites, but parasites and diseases do not appear to cause significant mortality among C. gigas in the Netherlands. The apparent lack of natural predators and the low vulnerability to parasites and diseases in the Netherlands is likely to have contributed to the oyster’s invasion success. However, in recent years a virulent new strain of the oyster herpes virus (OsHV-1 μVar) has caused massive mortalities of Pacific oysters in France and this has now spread to Oosterschelde, but is not yet present in Lake Grevelingen (by 2011). This virus is temperature dependent and only causes oyster mortalities when the temperature exceeds 16°C. The oyster herpes does not affect O.edulis.

3.3.2 Stock Status

Crassostrea gigas C. gigas is a very high fecundity species (50-120 million eggs at one spawning), with early first sexual maturity, so the reproductive potential is extremely high and very large numbers of spat can be produced from a very small spawning stock biomass. After its introduction into Oosterschelde by oyster farmers in 1964 the first natural spatfall of C. gigas was recorded in 1975 (Smaal et al 2008). This was followed by very large settlements in 1976, 1982 and 1986, all years with very warm summers (Diederich et al 2004), and the stock proliferated enormously. With the more frequent occurrence of warm summers, and rapidly increasing spawning stocks, the recent history is of very high spat settlement and survival in both Oosterschelde and Grevelingen. In the cultivated plots settlement is promoted by depositing mussel shells as cultch for the oyster larvae to settle on (usually in May/ June).

While the presence of a large spawning stock biomass of Pacific oysters in both Oosterschelde and Grevelingen has been readily apparent from visual observations of the extensive intertidal oyster reefs, until very recently there have been few quantitative estimates of stock biomass. Some data are available for the period 1999-2005 but a more extensive survey of the Pacific oyster stocks in Oosterschelde was undertaken by IMARES (a Dutch science provision organisation) in 2011

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(Brummelhuis et al., 2011) under a contract commissioned by the Ministry of Agriculture. This survey will now be repeated annually but no survey of stock biomass has been carried out in Grevelingen.

The IMARES survey aims to assess the wild stocks of Pacific oyster in the intertidal areas of Oosterschelde, but does not include the subtidal areas or the cultivated plots. The 2011 survey produced contour maps of the beds and took quantitative samples to estimate total wet biomass. The stock of Pacific oysters in the intertidal areas of the Oosterschelde was estimated to cover 845 ha (outside the culture plots) plus 175 ha (inside the culture plots); the geographical locations of the intertidal oyster beds are indicated in Figure 1.

The estimated mean biomass of oysters was 72.1 kg.m-2 fresh weight, corresponding with 2.6 kg.m-2 boiled flesh weight. The total fresh weight (including the shell) of the oyster beds in 2011 was 85 million kg (ranging between 59-111 million kg) or 4 million kg flesh weight.

Pacific oysters in the sublittoral zone were found only in low abundance (Figure 2) at densities < 10 oysters per m2. Relatively high densities were found at the edges of tidal flats, where the intertidal oyster beds extend into the sublittoral.

It is possible that the abundance of Pacific oysters in Oosterschelde may now be declining due to the Oyster herpes virus (OsHV-1 μVar) (A. Comelisse, Boat skipper Pers. comm.), which may have been introduced via France and first detected in Oosterschelde in 2009 but this has not be confirmed by any quantitative studies. The Oyster herpes virus is not yet present in Grevelingen (up to 2011).

IMARES Stock survey 2011 (Oosterschelde) of intertidal Pacific oyster (C. gigas). Source: Brummelhuis et al., 2011.

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Sublitoral occurrence of Pacific oysters in Oosterschelde, spring 2011 (Brummelhuis et al., 2011).

Ostrea edulis The spawning stock biomass of the native oyster Ostrea edulis in both Oosterschelde and Grevelingen is not known as no quantitative surveys have been carried out. Catches of some 1M oysters per annum

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from commercial plots in Grevelingen over the last 20 years indicate a sizeable SSB, though this is very small compared with the stocks present before the severe winter mortality in 1962/3 (Drinkwaard, 1999 a, b). Since 1980, continuing infestation with the protozoan parasite Bonamia ostrea has limited stock size and makes early harvesting essential. Reported catches from Oosterschelde are very low and of no commercial significance. O. edulis is a high fecundity species (ca. 1-2 M larvae released at one spawning) with early first sexual maturity (1-2 years) so the reproductive potential is high and large numbers of spat can be produced from a very small spawning stock biomass. There is a recent history of regular, good, spat settlement in cultivated plots in Grevelingen (approx. 50% O.edulis: 50% C.gigas), promoted by later deposition of mussel shells as cultch (typically in July) since O.edulis larvae settle later than C.gigas. Recent spat settlement in Oosterschelde is very low and out-competed for space by C.gigas.

The fisheries for both Crassostrea gigas and Ostrea edulis in Oosterschelde and Grevelingen are enhanced fisheries with the major production coming from the cultivated plots, which are managed to promote a high density of settlement by providing mussel shell material at the appropriate time for the naturally produced larvae to settle upon. These are therefore catch and grow fisheries, based on the collection of spat that arises from spawning stock located both in the cultivated plots and in the wild populations outside. For O.edulis in Grevelingen and, to a lesser extend for C. gigas in both locations, a major part of the spawning stock biomass is contained in the cultivated plots where the high densities promote high fertilization success. O edulis is very rare in Oosterschelde and no significant targeted fishery exists. Some individuals may be taken and will be sold with Grevelingen eduylis.

For C. gigas there are very substantial spawning stocks in both Oosterschelde and Grevelingen outside the cultivated plots, in both intertidal and subtidal areas. While the IMARES survey programme started in 2011 provides an assessment of wild C. gigas biomass in the intertidal areas of Oosterschelde, there are no quantitative estimates of the total spawning stock biomass in Oosterschelde or Grevelingen for either species. No analytical assessments are made of these fisheries, no TAC’s are set, no biological reference points are calculated and the status of the stock relative to unfished cannot be assessed. There are, therefore, not sufficient data available to enable a conventional assessment to be carried out so it is necessary to use the RBF to assess PI 1.1.1

3.3.3 Biological limits on stock status (Reference Points)

There are no explicit or implicit target or limit reference points available for the enhanced fisheries for either Crassostrea gigas or Ostrea edulis. Since the RBF was used to score PI 1.1.1., a default score of 80 will be awarded for PI 1.1.2 for both fisheries.

3.3.4 Harvest Strategy

The national harvest strategy for the oyster fishery is set out in the policy document “Ruimte voor een Zilte Oogst” (2004) which states that the aim is to produce an economically viable shellfish sector while using production methods that respect or even enhance the natural values of the ecosystem. For the oyster fishery, this requires that ecosystem effects are taken into account when considering future economic developments. The Pacific oyster is seen as a threat to the ecosystem that can be managed by allowing a fishery. Since there is no direct consumption of Pacific oysters by birds, a policy of food reservation for birds (as exists for the cockle and mussel fisheries) is not necessary.

For oyster production in Oosterschelde and Grevelingen, areas of seabed are licensed as cultivation plots: in Oosterschelde there are 310 plots totalling 1550 ha (all in the eastern region known as the Kom), while in Grevelingen there are 110 plots, totalling 550 ha. The plots were originally granted in the 1950s and are renewed annually. The current policy is not to issue any further licences but they can be traded, allowing new people to enter the fishery. There are currently some 30 individuals or companies holding licences, with individuals or companies holding from 2 -20 plots each. The plots

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are managed by the licensee who is responsible for maintaining the productivity of the plot and has the sole right to harvest oysters within their plot.

In addition to the cultivated plots there are free grounds where oyster dredging is permitted in Oosterschelde (but not in Grevelingen) and the oysters caught here may be marketed or relayed on cultivated plots. There are some permitted open areas outside the Kom but dredging on the intertidal flats is only allowed in the Kom. It is not permitted to move oysters from Oosterschelde to Grevelingen. The fishery for oysters is regulated by an annual Fish Plan drawn up by the Dutch Oyster Association and approved by the Ministry.

Oysters within the cultivation plots are the property of the licencee and can be harvested whenever required. Since these oysters originate, at least in part, from larvae spawned by the wild populations and settling as spat in the cultivated plots, or as adult oysters relayed from the free grounds, the key issue is whether this initial capture of stock leads to the depletion of the wild populations. However, this is highly unlikely because oysters in the cultivated plots start to spawn before capture and the plots are managed to maintain high densities, which enhances fertilization success, so the cultivated plots are most likely to be net exporters of larvae.

The harvest strategy for Crassostrea gigas imposes few limits on its exploitation as it is considered as an introduced invasive species that out-competes and limits the production of the more valuable native oyster, Ostrea edulis. In Grevelingen, C.gigas is removed from the vicinity of beaches and other tourist facilities, crushed and disposed of, as the sharp edges to the shell can cut the feet of recreational users indicating its essentially ‘nuisance’ status there. In the cultivation of C.gigas, spat are encouraged to settle by spreading crushed mussel shells as spat collectors onto the seabed within plots in May and June; after spat settlement this is then retrieved and seeded onto the subtidal cultivation plots. These oysters are then dredged up, graded by size and relayed several times a year. The cultivated plots are therefore used on a 3-year cycle: spat settlement, growth and harvesting. Pacific oysters are harvested from a size of 60-70g, up to about 250g to supply different markets. This is normally at an age of 2-3 years old but in Grevelingen, where growth rates are faster, they can be harvested from 18 months old or left to get larger.

The cultivated plots in Grevelingen are managed to promote the settlement, growth and survival of O. edulis, rather than the much less valuable C. gigas or other competing organisms. This is achieved by depositing the spat collectors (usually crushed mussel shells) later in the summer (in July), as O.edulis larvae settle later in the year. Unlike C. gigas, the more delicate O. edulis are not dredged up and graded until they reach marketable size. The usual harvesting strategy for Ostrea edulis is to harvest them at the end of the second year (at 50-60g) to avoid mortalities by Bonamia, but if the incidence of Bonamia is low then harvesting may be delayed until the oysters are three years old to produce larger, more valuable, oysters (at 80-90g).

With limited supplies of local mussels shells available, and increasing restrictions on importing shell material from elsewhere, the cost of spat collector material is going up and oyster farmers are now seeking to improve the quality of their product by experimenting with different forms of off-bottom culture. However, this assessment is only concerned with oysters harvested by dredge.

In addition to the commercial exploitation, members of the public are allowed to harvest up to 10 kg of shellfish (gross weight) per person per day (from outside the cultivation plots and closed areas but only during the daytime). These are taken mostly from the dykes but the totals harvested are very small in relation to the total stock.

There are a number of regulations in place on the importation of living shellfish into Oosterschelde and Grevelingen from other areas that aim to prevent the further importation of alien species and diseases.

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3.3.5 Harvest Control Rules and Tools

Harvest controls are very well defined, and are set out in the fishing licences issued to each operator in the fishery. The fishermen need several licences and permits to exploit oysters in Oosterschelde and Lake Grevelingen. First, there are the public law and private law fishing permits for the fishery, both of which list a series of conditions under which the permit holder may fish for oysters on the free grounds in Oosterschelde. In addition, a licence issued under the Nature Conservation Act is required: the current licence is valid until the end of 2012. Finally, there are agreements on the use of the culture plots that are renewed every year.

Management of the fishery is overseen by the Dutch Oyster Association, which produces an annual Fishing Plan (e.g. Reglement Visplan 2012) that aims to establish a controlled fishery on the free grounds and on the culture plots. It includes the relevant rules listed in the fishing permits and Nature Conservation Act licences, and specifies the following (text in italic):

The fishing season starts on the 1st January and ends on 31st December. The fishery on the culture plots is allowed during week-days during daylight, and on Saturdays from sunrise to 12:00 h, with the exception of generally recognised Christian holidays (Boxing Day excluded) or when the visibility is <250 m. Fishing on the free grounds is allowed during weekdays (but not on Saturdays) during daylight, except on Christian holidays and when the visibility is <250 m. The Board of the Dutch Oyster Association is authorised to close the oyster fishery (either totally or partially) in special circumstances.

Participants are obliged to use a Larus blackbox GPS-based position logging system on board all vessels participating in the fishery on both the free grounds and on the culture plots. The blackbox system (BBS) must be used throughout the whole fishing season, the BBS or the antenna for the reception of the GPS signal must not be modified, instructions for use must be followed and every fault of the BBS should be reported immediately to the supplier. The BBS data are read out periodically on behalf of the Dutch Oyster Association by the Producers Organisation “PO Mosselcultuur” who must treat all information obtained as confidential. These data can be used to determine if the fishing plan has been violated, or for analysing fishing activity (not aiming at individual participants).

Conditions that apply to the fishery on the free grounds are: a). Fishing is only allowed if the participant has the required permits from the Ministry, including all connected conditions, and if the participant can show the permits immediately when requested. b). Fishing should be practiced with the vessel for which the permit was given, or with a fishing vessel that is named on the permit of another permit-keeper. c). A replacement vessel can be used only if it is reported beforehand to the secretariat of the Association, if the vessel has a public law licence from the Ministry and it has the Larus blackbox system. d). Fishing outside the free grounds is not permitted, unless inside plots that are rented by the permit- keeper.

Conditions that apply to the fishery inside the cultivated plots are: a). Fishing outside the licence holder’s own plots is not permitted, unless the participant is allowed by the government to fish oysters that were sewn outside his plots, or if the fishery is undertaken on the free grounds in Oosterschelde and the participant has the necessary permit (“publiekrechtelijke vergunning”). b). All conditions of the agreements on the culture plots (“Akten van verhuring van visrecht”) should be followed in Oosterschelde and Lake Grevelingen.

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c). A replacement vessel can be used only if it is reported beforehand to the secretariat of the Association, and it has the Larus blackbox system.

In addition to the culture plots, there are restrictions on the areas where oyster dredgers can operate, with closed areas to protect nature conservation areas, set net fisheries etc. Since the Oosterschelde is a Natura 2000 site annual reporting of landings of oysters and spat are required and an Appropriate Assessment is required every 3 years to evaluate the effects of the fishery.

It is forbidden to distribute oysters and other living creatures into Lake Grevelingen that originate from outside Lake Grevelingen. It is also forbidden to use substrate to enhance spatfall that originates from outside Lake Grevelingen, unless it has been treated in a way that no marine organisms are attached.

The dredges used in this fishery must have a maximum width of 1.90m.

There are financial penalties for contravention of the Fishing Plan, which can be imposed by both the Dutch Oyster Association (maximum €23,000) and the Ministry (maximum €10,000).

The Nb-permit in addition forbids fishing in seagrass beds. It includes rules of keeping distance to birds (500 m) and seals (1500 m).

3.3.6 Information and Monitoring

There is a considerable amount of published literature on the biology and fishery of oysters in Oosterschelde and Grevelingen. The earlier literature is all about the native oyster Ostrea edulis (e.g. Korringa, 1940, 1952, 1957) but since the early 1960s scientific study has concentrated on the demise of the native oyster stocks and the introduction and spread of the Pacific oyster, Crassostrea gigas (e.g. Drinkwaard 1999a, b; Wolff 2005; Smaal et al. 2009; Fey et al. 2010) and the various pests and diseases that have been introduced with the imported oysters (e.g. Van Banning 1991; Reise, 1998;Wolff & Reise 2002; Faasse & Ligthart 2007, Haydar & Wolff 2011).

Good records of fishery removals are made by the Dutch Oyster Association, with independent monitoring by the Fishery Inspectorate. Historical records of stock abundance are limited but a survey of wild Pacific oyster stock biomass in the intertidal area in Oosterschelde was made in 2011 by IMARES and this will now be assessed annually. There is also limited information available on stock structure and productivity, though carrying capacity is now being assessed in a study that will end in 2013. In Grevelingen the exploited stocks are all within the cultivated plots, with no areas open to a free fishery, so these stocks are not assessed. With the only major populations of O.edulis within the cultivated plots in Grevelingen there is little survey data or monitoring directed at this species, although O.edulis would appear and be recorded in the C. gigas surveys if they became more abundant elsewhere.

Fleet composition information is excellent and fishing activity is recorded by blackbox VMS and monitored by the Dutch Oyster Association, with additional monitoring by the Fisheries Inspectorate.

A ‘Knowledge Group for Oysters’ has now been set up involving IMARES and other biological research institutes, together with economists and 6-8 oyster cultivators to look at future research requirements of the oyster industry.

3.3.7 Assessment of Stock Status

As this is an enhanced, catch and grow, fishery there are two components to the stocks of both Crassostrea gigas and Ostrea edulis: the stocks on the culture plots and the wild stocks elsewhere.

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The status of the cultivated stock is monitored by each oyster farmer within their leased plots, and the plots are managed to maximise production of C. gigas in Oosterschelde and O. edulis in Grevelingen. The wild stocks of C. gigas in the intertidal areas of Oosterschelde were assessed in 2011 by IMARES, and will now be assessed annually, but the subtidal populations were not assessed, no assessments of either species have been made in Grevelingen and there are no good historical time series of stock data available. With no quantitative data available, no analytical assessments have been made for these fisheries, no TAC’s are set, no biological reference points are calculated and the status of the stocks relative to unfished cannot be assessed. There are, therefore, not sufficient data available to enable a conventional assessment to be carried out so the RBF was used to assess PI 1.1.1 and a default score of 80 awarded for PI 1.2.4 for both species in accordance with the MSC Fishery Requirements.

3.4 Principle Two: Ecosystem Background

3.4.1 Background to Ecosystem Within Which Fishery Operates

The Oosterschelde and Lake Grevelingen are both part of the Rhine-Meuse-Scheldt Delta in the southwest of the Netherlands. After the disastrous storm surge in January 1953, the national safety plan (Deltaplan) was enacted to prevent flooding. The resulting Delta works, a coherent and carefully planned construction of dams, sluices, levees, dikes and storm surge barriers, caused very drastic changes to the marine ecosystems of Oosterschelde and Grevelingen.

In 1965, the Grevelingendam was closed and it separated Grevelingen from Krammer-Volkerak. Subsequently, the Brouwersdam was constructed at the seaward side. This dam was closed in 1971, separating Grevelingen from the North Sea to create the brackish Lake Grevelingen. In 1978, the Brouwersdam was perforated with sluices to enable some exchange between North Sea and Lake Grevelingen; water exchange was allowed only during winter. Since 1999, the Brouwersdam inlet is opened year-round. The Flakkeese sluizen in the Grevelingendam were re-used since 2009 and create an enhanced water exchange between Oosterschelde and Lake Grevelingen (Bouma et al., 2008).

In the southeastern part of Oosterschelde, the Oesterdam (1986) was constructed with the aim of reducing the water volume of this waterbody and to facilitate shipping traffic between Rotterdam and Antwerp through the Schelde-Rijnverbinding. The Philipsdam (1987) cut off the northern branch of Oosterschelde from Krammer-Volkerak. In 1986, the permeable storm surge barrier “Oosterschelde- kering” was constructed. As a consequence there was a reduced input of fresh water, a reduced exchange of marine water and a reduced tidal range in Oosterschelde.

Oosterschelde In the Oosterschelde (surface area 370 km2), different geographical sub-areas can be distinguished: Monding (western part), Midden (central part), Noordtak (northern branch), Kom (eastern branch). Each has its own characteristics. The Monding is characterised by deep water (12 m on average), whereas the Kom is quite shallow (mean depth 4 m).

Due to its high and outstanding natural qualities, the Oosterschelde was designated as a State Nature Reserve in 1990, as a National Park (Nationaal Park) in 2002 and as a Natura 2000 area in 2009.

After the completion of the Deltaworks, the Oosterschelde gradually changed from an estuary to a shallow marine embayment. It now has a stable high salinity of c. 30 PSU. The Oosterscheldekering is only closed during exceptional storm conditions, but the tidal prism and tidal range of Oosterschelde have been restricted due to the dam. As a consequence of the reduction of the tidal prism, the gullies adapt to a new equilibrium situation and tend to fill with sediment; this process is called “zandhonger”. The sediment exchange with the North Sea is limited and so sediment can only be

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drawn from the tidal flats in the Oosterschelde. As a consequence, the intertidal area is reducing by around 50 ha per year (Geurts van Kessel, 2004).

The mean tidal volume of Oosterschelde was originally 1230 x 106 m3 and is now 880 x 106 m3 (- 28%). At Yerseke, the mean tidal range is 3.25 m. The residence time of the water is 10-150 d (Smaal & Nienhuis, 1994). Different types of habitats are found in the Oosterschelde: open water (304 km2), intertidal sand and mudflats (118 km2), supratidal salt marshes (6,4 km2), as well as hard substrates (dike slopes) and peat banks. The foodweb is dominated by phytoplankton (primary production), benthic filter feeding molluscs (secondary level) and carnivorous birds and man (tertiary level) (Nienhuis & Smaal, 1994). Eelgrass (Zostera noltii) used to be common, but its area has reduced and eelgrass is now present only in low coverage in some shallow parts of the Northern branch and Kom (data RWS-DID, 2011).

Traditionally, the (shellfish) fishery (flat oyster Ostrea edulis and mussel Mytilus edulis) has been an important economic activity for the Zeeuwse population. At present, the flat oyster has diminished due to the Bonaemia disease and the culture of the introduced Pacific oyster (Crassostrea gigas) has taken over.

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Grevelingen

The former estuary Grevelingen (110 km2) was changed into a brackish lake without tidal influence after the construction of Grevelingendam and Brouwersdam. Shallow parts, that used to emerge only during low tide, are now permanently dry and covered with vegetation (e.g. Hompelvoet, Veermansplaat, Stampersplaat). The former tidal channels are up to 25 m deep. The shallow areas (<1.5 m deep) cover c. 40 km2. Lake Grevelingen is the largest marine lake in Europe, including a number of islands and shores with extended dune vegetations and salty pioneer vegetation. It is an important area for fish eating birds.

Topography of Lake Grevelingen with the names of the closures indicated.

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Map of Lake Grevelingen with the names of the former tidal flats indicated (source: www.grevelingen.nl).

Over the years, the management of Lake Grevelingen was modified constantly, answering to the sequence of ecosystem problems that occurred. Currently, there are still ecological problems in Lake Grevelingen, caused by a persistent stratification of water layers and the development of anoxic conditions in the deeper water layers due to decomposition of the accumulated sediment, which is loaded with organic matter. Management aims at <5% anoxic bottom area, but this is not achieved; currently 10% of the bottom area can get anoxic and the problems no longer occur only in the deeper part but also in areas shallower than 5-6 m and the oxygen problems are therefore now also affecting the commercial oyster plots. Salinity fluctuates around 17 g/l Cl which is at a similar level to the salinity in Oosterschelde. Transparency of the water decreased over the years to 2-2.5 m (stable) and is now at comparable levels to Oosterschelde (Bouma et al., 2008, Wetsteijn, 2011).

3.4.2 Retained Species (retained by-catch or by-product)

The plots (on Oosterschelde and Grevelingen) are managed almost exclusively for oyster, and so no bycatch species are present. In the Oosterschelde free ground, mussels (Mytilus edulis) may occur mixed with oysters and therefore may be fished at the same time. However, the fishing permit demands that all other shellfish than oyster should immediately be put back if their share in the catch is >15% of the gross catch weight. Processing requirements mean that dealing with such small amounts of bycatch is uneconomic and so the oyster fishery has no retained species other than the target species.

3.4.3 By-catch Species (discarded bycatch)

There is very little systematic recording of bycatches in the Dutch oyster fishery. Bycatch may consist of the benthic fauna, living amongst oyster beds, or the benthic epiflora and fauna, attached to or associated with the oyster shells. The epiflora and fauna on the flat oyster O. edulis were first

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described by Korringa (1951) and were recently listed by Haydar & Wolff (2011), who found as much as 41 species of macroalgae associated with oysters.

Impacts on bycatch may arise in the free ground fishery and on cultured plots. The bycatch in the fishery on the culture plots is restricted to the maximum area of the plots (1550 ha in Oosterschelde and 500 ha in Lake Grevelingen). The culture plots are manipulated and the fauna living on the culture plots highly depend on the presence of the cultured oysters. Impacts here are expected to be minimal and extremely localised.

Effects on bycatch species of the free grounds has been studied in an oyster removal experiment that was carried out in Oosterschelde (Wijsman et al., 2008). Initially, there was found a clear distinction between the benthic macrofauna, occurring in sublittoral or in littoral oyster beds, with a richer fauna in the littoral areas (89 species) than in the sublittoral areas (63 species). Harvesting of oysters did not lead to structural, irreversible changes in the composition of the macrobenthos community (Wijsman et al., 2008). Before the experimental removal, the oyster beds contained more species than the reference areas. IMARES conclude that no irreversible damage occurred to the benthic macrofauna as a consequence of the oyster fishery. However, there is little systematic information available on the bycatch.

3.4.4 Endangered, Threatened and Protected Species (ETP)

The most important legislation affecting nature conservation in the Oosterschelde and Lake Grevelingen is the EU Habitats Directive and Birds Directive – giving rise to protection of habitats and species within Natura 2000 sites (‘European Sites’). Harbour seal and several seabirds are protected under this legislation, but none interact directly with the oyster fishery in either waterbody. Indirect effects are limited to possible disturbance by vessels of roosts, feeding areas or seal haul-out areas; oysters do not form a significant food source for any of these species.

Although not binding national legislation, the OSPAR (2008) list of Threatened and/or Declining species and habitats include the following, relevant to Oosterschelde and/or Grevelingen:

 Dogwhelk (Purperslak) Nucella lapilus: occurs in Oosterschelde (recovering from TBT- impact), disappeared from Grevelingen after closure of the Brouwersdam in 1971 and was not found there since 1978 (Gmelig Meyling et al., 2006).  Native Oyster (Platte Oester) Ostrea edulis: occurs in Oosterschelde and Grevelingen. The species is severely impacted by Bonamia-disease. The native oyster in Lake Grevelingen is cultivated and its presence is enhanced by collecting the natural spatfall.  Intertidal mud flats: occur in Oosterschelde; the area of intertidal flats is getting reduced as a consequence of the changed morphodynamic conditions (“zandhonger”). In Grevelingen, the intertidal mud flats disappeared after closure, because there is no dynamic tidal range left. The oysterfishery does not form a threat for the intertidal mudflats; on the contrary, the presence of oysters along the tidal flats can reduce the erosion by “zandhonger”.  Intertidal mussel beds of Mytilus edulis: no longer present in Oosterschelde in its natural form since the construction of the Oosterscheldekering. There is mussel culture and rope culture of mussel seed (MZI).  Ostrea edulis beds: present in (Oosterschelde and) Grevelingen, no longer in natural form. Management measures, suggested in the Ospar “case document”, are the regulation of directed fishery, control the spread of introduced species, reduce the risk of disease transmission, maintain suitable habitat for spatfall. These measures are already in place.  Zostera beds: occur in Oosterschelde only in intertidal areas and is very scarce; disappeared from Grevelingen due to changed salinity. There is a condition included in the NB-permit for not fishing in Zostera beds.

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3.4.5 Habitats

Oosterschelde

The Oosterschelde is designated as a shallow marine bay (H1160 – Grote baaien) in Natura 2000. It consists of different ecotopes, such as large areas of water and tidal channels; subtidal and intertidal sandy or muddy tidal flats. Special habitats are formed by banks of mussels, oysters or cockles and seagrass. In the Netherlands, the habitat type ‘marine bay’ (H1160) is only found in Oosterschelde. The quality of Oosterschelde is determined by the variation of different ecotopes and its associated biodiversity. Typical species, characteristic for the habitat type H1160 and occurring inside this water body, are listed in the Table below.

Scientific name Dutch name English name Metridium senile Zeeanjelier sea anemone Arenicola marina Wadpier Lugworm Lanice conchilega Schelpkokerworm Sand mason Nephtys hombergii Zandzager Catworm Nereis diversicolor Zeeduizendpoot Ragworm Carcinus maenas Gewone strandkrab Shore crab Urothoe poseidonis Buldozerkreeftje Amphipod Zostera marina Groot zeegras Eelgrass Zostera noltii Klein zeegras Dwarf eelgrass Platichthys flesus Bot Flounder Clupea harengus Haring Herring Zoarces viviparus Puitaal Eelpout Limanda limanda Schar Dab Pleuronectes platessa Schol Plaice Trisopterus luscus Steenbolk Bib Merlangius merlangius Wijting Whiting Myoxocephalus scorpius Zeedonderpad Bull rout Echinocardium cordatum Hartegel Heart urchin Cerastoderma edule Kokkel Cockle Mytilus edulis Mossel Mussel

Characteristics of a good structure and functioning of this habitat type (H1160) are the presence of :  tidal currents  natural tidal channels  a variation of sandy and silty parts and transitions  a variation in elevation, with tidal flats that are permanently submersed and tidal flats that emerge during low tide  a variation of areas with high and low dynamics  a good water quality in terms of transparency and salinity  seagrass and ruppia  mussel beds with high numbers of associated species  algae or a film of diatoms and cyanobacteria  completeness of the ecosystem in terms of  biomass, density and diversity of macrobenthic organisms  abundance and species diversity of the fish fauna  abundance and species diversity of the bird populations  abundance and species diversity of marine mammals  the presence of saltmarshes along the borders

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Sea grass The presence of seagrass in the Dutch coastal waters is monitored and reported each year (EFTAS, 2010). Only dwarf eelgrass Zostera noltii is found at 6 locations in the Oosterschelde (see Fig. below), in total 90.8 ha (2010). The locations 10, 11 and 12 are situated in the Kom, which is also the area where the oyster culture plots are situated. However, dwarf eelgrass grows in the shallow intertidal areas whereas the oyster plots are found in deeper water.

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Lake Grevelingen

The designation of Lake Grevelingen as a Natura 2000 area is pending; a preliminary designation was assigned in September 2008. The habitats that are listed for this Natura 2000 area are all on land or in the supratidal zone and will therefore not be affected by the current activities of the Oyster culture. See section 3.4.1 for a description of the background of the ecosystem.

3.4.6 General Ecosystem Effects

Both Oosterschelde and Grevelingen ecosystems have been influenced and changed to a large extent by a combination of the Delta works and the associated management of the areas, temperature rise, TBT (anti-fouling) and active import of (exotic) organisms by mussel/oyster culture and/or ballast water.

After the completion of the Deltaworks, the Oosterschelde gradually changed from being an estuary to a shallow marine embayment. It now has a stable high salinity of c. 30 PSU. The Oosterscheldekering is only closed during exceptional storm conditions, but the tidal prism and tidal range of Oosterschelde have been restricted due to the dam. As a consequence of the reduction of the tidal prism, the gullies adapt to a new equilibrium situation and tend to fill with sediment; this process is called “zandhonger”.

Oysters have been partly attributed with a positive role in stabilising intertidal areas. Due to the expansion of the Pacific oyster, by providing suitable settlement substratum, the native mussel Mytilus edulis was reintroduced in the intertidal areas of Oosterschelde (Troost, 2009). There is some ecological niche overlap between the different shellfish species, where C. gigas is restricted to the low intertidal and the other species may also occur higher in the intertidal. It is not believed that there is competition for space between the shellfish species (although the “zandhonger” phenomenon may reduce the area of the high intertidal).

Oysters do not fulfil a prey role in either system. As filter-feeders, they will compete with other species such as mussels for food; there are indications that there is competition for food and even that the carrying capacity of Oosterschelde is limiting for the production of shellfish. The recruitment of shellfish may also be limited by larvifagy (shellfish consuming their own larvae), causing 95% larval mortality. It is not believed that any species will disappear due to competition (Troost, 2009).

Shellfish culture has also led to the introduction of considerable numbers of exotic species. At least 8- 9 of these species were introduced in the Netherlands by oyster (and mussel) culture (Wijnhoven & Hummel, 2009). The most recent documented introduction associated with oyster culture is that of the Japanese oysterdrill Ocinebrellus inornatus, which was first recorded in the Netherlands in 2007 (Haydar & Wolff, 2011).

In the Oosterschelde, exotic species contribute 7.4% to the density and 41% to the biomass of benthic organisms (Van Wijnhoven & Hummel, 2009; Wetsteijn, 2011).

Introduced exotic species in the Oosterschelde, probably due to the shellfish culture include: Syllidia armata Proceraea cornuta Sylis gracilis Crepidula fornicata Crassostrea gigas Styela clava Hemigrapsus penicillatus

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Gibbula spp.

For a number of other species, their introduction may have been caused either by the oyster culture, the mussel culture or by ballast water/ship transports.

In Grevelingen, in terms of density of benthic organisms, 23% consists of exotic species; in terms of biomass, 70% is contributed by exotic species. The slipper limpet (Crepidula fornicata) is by far the dominant exotic species (Wetsteijn, 2011). Other introduced species in Lake Grevelingen are Crassostrea gigas, Ensis directus and Mya arenaria. The Pacific oyster is also quite dominant in Lake Grevelingen.

3.5 Principle Three: Management System Background

3.5.1 Management Background

The Oyster fishery takes place in the Oosterschelde and Lake Grevelingen. Both of these are European Sites designated under the EC Habitats Directive. Nature conservation therefore plays a major role in the management of the fishery; in particular, the fishery, as a ‘plan or project’ under the Directive, requires a regularly updated Appropriate Assessment identifying any impacts arising from the fishery which could compromise its nature conservation status. Through PO Mossel and/or Productschap Vis (the Dutch fisheries marketing organisation), the NOV are represented in the stakeholders that participate in the process of establishing the Natura 2000 management plan for the Delta waters.

As both systems have been the subject of enclosures following the floods of 1953, management of the water bodies, and ecological stabilisation, are both ongoing; Rijkwaterstaat has a process to allow stakeholder input into this and other projects..

The National Park Oosterschelde has an “overlegorgaan” (board) including a representative for the fishery and PVis. However, the fishery policy is determined at a national level, which leaves little manoeuvring space within the management of the National Park Oosterschelde.

In both Oosterschelde and Grevelingen, the majority of the fishery takes place in ‘plots’ allocated to individual fishers; all individual plots are of 5 ha. In Oosterschelde, fishers are also able to fish on ‘free grounds’; fishing in Grevelingen is restricted to plots. Plots are subject to rental agreements (Overeenkomst voor de verhuring van visrecht voor oesterpercelen in de Oosterschelde) for three years. Fishing on free grounds requires a private law and public law fishing licence (Schriftelijke toestemming voor het vissen van oesters op de vrije gronden in de Oosterschelde), as well as a Nature Conservation Permit (Nb-vergunning) under the Nature Conservation Act.

Permit holders are all members of the Dutch Oyster Association (NOV); membership of the DOA is outlined below. Permit and other restrictions are developed by the NOV into a ‘Fishing Plan’ which provides an operational document for fishers.

3.5.2 Legal Framework of Management System

As above, the fishery operates within a legal framework designed for both fishery management and nature conservation. Key legislation includes:  Visserijwet 1963 (Dutch Fishery law) which sets out basic operating parameters for fisheries.  Waterwet 2009, reglementing the use and management of surface water and groundwater

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 Water Framework Directive (WFD 2000, in Dutch: Kaderrichtlijn Water, KRW) which requires maintenance of ecological function of waterbodies  Natuurbeschermingswet 1998 (Nb-wet; Nature protection law/ Nature Conservation Act)  Designation of Oosterschelde as State Nature Reserve (aanwijzing Staatsnatuurmonument) (20 December 1990)  Designation of Oosterschelde and Grevelingen as SAC Birds Directive and SAC Habitats Directive; Designations Natura 2000: Aanwijzingsbesluit Oosterschelde (23 December 2009), Ontwerp Aanwijzingsbesluit Grevelingen: (draft, 10 September 2008).

Policy documents on the shellfish fishery “Ruimte voor een zilte oogst” (2004)  Oosterschelde: 16% areas closed for (shellfish)fishery;  Food reservation policy (cockles, mussels) for Oystercatchers  “Beleidslijn inzake Verplaatsing Schelpdieren (TRC 97/2901)”; adapted in 2003; expert judgement on “Verplaatsingsproblematiek Schelpdieren”.This policy document deals with transports of shellfish between different parts of the Wadden Sea and between the South of the NL and the Wadden Sea. There are risks of transporting diseases and of introducing exotic or invasive species.

Management documents  “Van de parels en het slik” Nationaal Park Oosterschelde (2001).  Management plan Natura 2000: “Beheerplan Deltawateren” (in prep.); underlying document: “Globale en Nadere effectenanalyse” (Rijkswaterstaat and Ministry of EL&I, 2011).

Access to the oyster fishery requires  Fishing permit  Nb-permit (nature permit to fish on free grounds)  Blackbox system operational (VMS)  Oyster fishers need private law and/or public law fishing licences (see documentation). These documents describe the rules and regulations for access; they are embedded in the Visplan (Fishing plan).

The management of the fishery on the free grounds in the Oosterschelde aims at no further increase of the number of permits for bottom-disturbing fishery activities. Current licences can be transferred, however. Each licence allows free oyster fishery with a vessel. Further developments of oyster culture are permitted; initiatives are judged positively, but according to their compliance with existing frameworks. Plots on Oosterschelde are restricted to 1550 ha, located within the ‘Kom’ in the east of the waterbody.

The current Nb-permit is valid until 31 December 2012 and is granted to each member of the Dutch Oyster Association, as listed in annex 3 of the permit. The Nb-permit is based on an Appropriate Assessment of the effects of the fishery on the free grounds on the Natura 2000 area Oosterschelde. The “Reglement Visplan” and the Public law fishing licence describe the type of gear, with only restriction on the opening of the gear, which should not be wider than 1.90 m. The fishing licence also forbids the use of gear that apply suction of shellfish. Usually, each vessel has 2-4 dredges.

As the main functions of Grevelingen are nature and recreation, therefore there is a limitation of max. 500 ha culture plots. This can be revised with mutual agreement between VBC (visserij beheer commissie; fishery management committee) and Grevelingenschap (Grevelingen board for recreation and tourism).

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The live import of oysters and other bivalve molluscs to Oosterschelde is now regulated with licences, based on a policy document of 2003 and partial adaptations in 2004. Currently, the policy is in revision and the latest version is not yet published. The current best practice can be derived from a recent verdict of the Raad van State (February 2012), which allows the import of shellfish from Irish and UK waters with the application of a shellfish import protocol (Gittenberger, 2010), applicable to the import of mussels and oysters. The shellfish import protocol involves sampling in the area of origin in combination with the sampling of probes from ‘big bags’ that contain the imported shellfish.

3.5.3 Consultation, Roles and Responsibilities

The Dutch Oyster Association (NOV) is the umbrella organisation of Dutch oysterfishers and oyster growers. Nearly all oyster-producers have joined the Dutch Oyster Association, which was founded in 2007. Details of licence holders are provided in an official “List of license holders” (n=31); licences are valid 01-09-2009 to 31-12-2012 (source: VIRIS, Ministry of EL&I, dated 09-11-2009). Prior to issuance of licences, there is a 6 week consultation period.

The Ministry EL&I (Economie, Landbouw & Innovatie: economic affairs, agriculture and innovation) has overall responsibility for fishery management, with general inspection activities carried out by the Inspectorate division AID (Algemene Inspectie Dienst). Fishing permits and plot licences are issued by Min EL&I. The permit regulations and other rules of fishing are incorporated by NOV into an annual fishing plan. The fishing plan is subject to consultation, including discussions within an NOV annual meeting and with agencies involved in management of the Natura 2000 sites (including Rijkwaterstaat). The fishing plan is considered along with the Appropriate Assessment of effects on the Natura 2000 site.

The Netherlands marine science provider, IMARES, has a long involvement with fisheries in the area, including oyster fisheries, and carries out, among other activities, an annual survey of intertidal oyster beds. There is also cooperation between IMARES and the fishing sector in the “Kenniskring Oesterkweek”.

3.5.4 Long-Term (and Fishery-Specific) Management Objectives

The overall objectives for the fishery on the licensed plots are simply to maintain an economically viable fishery. Objectives for the oyster fishery on free grounds in Oosterschelde are to contribute to an economically viable fishery that respects the environment. Objectives for the Natura 2000 sites (Oosterschelde and Grevelingen) are to create and maintain a favourable conservation status for the features of importance in both sites.

3.5.5 Incentives for Sustainable Fishing

The majority of fishing activity takes place on licensed plots which fishermen lease on a commercial basis and effectively ‘cultivate’ to maximise returns. In Oosterschelde, this is supplemented by fishing on free grounds, which is carried out according to the fishing plan and is closely inspected. No subsidies are in place that would compromise sustainability of the fishery. Fishermen are also strongly encouraged (e.g. by the fish board Productschap Vis) to develop better methods of cultivating oysters to maximise returns while minimising environmental effects.

3.5.6 Decision-Making Processes

The regulation of the fishery is operationally achieved through the Fishing Plan, which incorporates licence conditions etc. The NOV meet 4 or 5 times per year; meetings include for annual review of the

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Fishing Plan. In tandem, the fishery is subject to an Appropriate Assessment which evaluates its effects on the Natura 200 sites (Oosterschelde and Grevelingen). Any significant adverse effects of the fishery would be accommodated within licence conditions and so the Fishing Plan.

3.5.7 Compliance and Enforcement

All vessels have VMS systems (black box), data from which provides the basis for monitoring and surveillance. Inspections may be carried out by AID at-sea and in port; AID also controls fishing on free grounds (under licence conditions) and rental agreements (together with water quality, bacteriology). Penalties for non-compliance are contained within the Fishing Plan and administered through NOV.

Regular meeting of NOV and reviews of Fishing Plan ensures fishers are aware of requirements. Little non-compliance has been confirmed by NOV and AID.

3.5.8 Research Planning

Research requirements for the Natura 2000 sites are identified, these will form part of the Ecological Management Plan for both Oosterschelde and Grevelingen ; these will include issues related to the fishery together with wider environmental aspects. General research requirements (associated with, e.g. effects of introduced species and the carrying capacity of Oosterschelde) are identified through the Knowledge Group for Oysters, including the Economics Institute, IMARES and NOV. These are considered to comprise separate but interacting research plans.

3.5.9 Monitoring and Evaluation of Management Performance

The key elements in the operation of the fishery are documented in the Fishing Plan. This contains elements of licence conditions for plots and, in Oosterschelde, the free ground fishery The Fishing Plan is reviewed annually by NOV. Licence conditions contained within the Fishing Plan are reviewed on a three-yearly basis by the Ministry; the effects of the fishery on the Natura 2000 sites are reviewed through the Appropriate Assessment mechanism.

4. Evaluation Procedure

4.1 Harmonised Fishery Assessment

These fisheries do not overlap with other oyster fisheries in the same areas. It is noted that an MSC assessment of the Cockle fishery in the Oosterschelde has been undertaken for OHV, with similar outcomes for Principle 3.

4.2 Previous assessments

This is the first assessment of these fisheries.

4.3 Assessment Methodologies

This assessment has used MSC Certification Requirements version 1.2 and MSC Full Assessment Reporting Template version 1.2.

The default assessment tree was used without adjustments.

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4.4 Evaluation Processes and Techniques

4.4.1 Site Visits

Information gathering was carried out principally during a visit to Yerseke, the main port for the oyster fleet. Itinerary and meetings were as follows:

13 March 2012. Site visit in Yerseke, Netherlands. Interviews and discussions on fishery with: J de Rooy, Secretary, NOV B Keus, Advisor NOV J Dingemanse, Member, NOV

K Troost, IMARES M Poelman IMARES

G-J van Veen, Fishery Inspector, AID

14 March 2012. Yerseke a.m. Observation of fishing activity on board NOV member vessel YE 60 in Kom, Oosterschelde. Aart Comelisse Skipper. p.m. SICA Workshop at offices of IMARES, Yerseke. Attending: B Keus, Advisor, NOV K Troost, IMARES A Smaal, IMARES

4.4.2 Consultations

Consultations were as above. Information obtained is summarised in Appendix 3 and presented throughout this report.

4.4.3 Evaluation Techniques

This assessment was announced through direct email to stakeholders, notification on the MSC website and an advertisement placed in Fishing News International – to attain maximum coverage of stakeholders.

The MSC Principles and Criteria set out the requirements of a certified fishery. The certification methodology adopted by the MSC involves the interpretation of these Principles and Criteria into specific Performance Indicators and Scoring Guideposts against which the performance of a fishery can be measured. In order to make the assessment process as clear and transparent as possible, these identify the level of performance necessary to achieve 100, 80 (a pass score), and 60 scores for each Indicator.

This re-assessment used the Standard Assessment Tree set out in MSC Certification Requirements. Use of this assessment tree has been the subject of stakeholder consultation. No comments were received on the use of this Assessment Tree.

Use of the RBF was notified to stakeholders in the fishery by email and via the MSC website. No comments were received on the use of the RBF. RBF was used for PIs 1.1.1, 2.1.1 and 2.2.1 because, although there is a significant amount of information on the ecosystem in question, it is not clear that

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this is entirely adequate, or in the form necessary, to evaluate target stock status, retained species status, by-catch status or habitat status. The MSC ‘Use of RBF’ form is appended in Appendix 1.2.

For each Performance Indicator, the performance of the fishery is assessed as a ‘score’. In order for the fishery to achieve certification, an overall score of 80 is considered necessary for each of the three Principles, 100 represent ideal best practice and 60 a measurable shortfall. A fishery cannot be certified if a score below 60 is recorded. As it is not considered possible to allocate precise scores, a scoring interval of five is therefore used in evaluations. Scores are allocated based on the consensus opinion of the assessment team.

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5 Traceability

5.1 Eligibility Date

The target eligibility date shall be 6 months prior to the issuance of the Public Comment Draft Report – 1 March 2012.

(REQUIRED FOR PCR ONLY)

The report shall include: a. The actual eligibility date. b. The rationale for any difference in this date from the target eligibility date

5.2 Traceability within the Fishery

Fishers will take oyster from their own plots to meet customer requirements. Landings are recorded by NOV and Productshap Vis; P Vis may also make inspections of landings. Oysters may then be sold or transported to market by fishers. Fishers would only operate within Oosterschelde and Grevelingen – all fishing would therefore be within the Units of Certification and there would be no opportunity for substitution of product prior to landing.

There is no at-sea processing or transhipment..

5.3 Eligibility to Enter Further Chains of Custody

Product is eligible to enter further Chain of Custody. All product landed by NOV members is eligible to enter Chain of Custody (all active fishermen are NOV members).

All landings take place at Yerseke.

As processing plants at Yerseke may contain oysters imported from other areas, Chain of Custody should commence at point of entry to processing plants or point of first sale, whichever is earliest.

5.4 Eligibility of Inseparable or Practically Inseparable (IPI) stock(s) to Enter Further Chains of Custody

There are no inseparable or practicably inseparable species are associated with this fishery.

6 Evaluation Results

6.1 Principle Level Scores

UoC 1 Pacific Oyster Crassostrea gigas, Oosterschelde

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Final Principle Scores Principle Score Principle 1 – Target Species 83.5 Principle 2 - Ecosystem 85.3 Principle 3 – Management System 89.9

UoC 2 Pacific Oyster Crassostrea gigas, Lake Grevelingen

Final Principle Scores Principle Score Principle 1 – Target Species 83.5 Principle 2 - Ecosystem 85.3 Principle 3 – Management System 89.9

UoC 3 Native Oyster Ostrea edulis, Lake Grevelingen

Final Principle Scores Principle Score Principle 1 – Target Species 90.0 Principle 2 - Ecosystem 85.3 Principle 3 – Management System 89.9

UoC 4 Native Oyster Ostrea edulis, Oosterschelde

Final Principle Scores Principle Score Principle 1 – Target Species 83.5 Principle 2 - Ecosystem 85.3 Principle 3 – Management System 89.9

6.2 Summary of Scores

The table below provides summary scores for UoC 1, 2 and 4. O edulis in Grevelingen scored the same except for PI 1.1.1 which scored 100.

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Prin- Wt Component Wt PI Performance Indicator (PI) Wt Weight ciple (L1) (L2) No. (L3) in Score Either Principl Or One 1 Outcome 0.5 1.1.1 Stock status 0.5 0.25 0.333 0.1667 94 1.1.2 Reference points 0.5 0.25 0.333 0.1667 80 1.1.3 Stock rebuilding 0.333 0.1667 Management 0.5 1.2.1 Harvest strategy 0.25 0.125 80 1.2. Harvest control rules & tools 0.25 0.125 80 1.2.2 Information & monitoring 0.25 0.125 80 1.2.3 Assessment of stock status 0.25 0.125 80 Two 1 Retained 0.2 2.1.4 Outcome 0.333 0.0667 100 species 2.1.1 Management 0.333 0.0667 80 2.1.2 Information 0.333 0.0667 80 Bycatch 0.2 2.2.3 Outcome 0.333 0.0667 100 species 2.2.1 Management 0.333 0.0667 80 2.2.2 Information 0.333 0.0667 65 ETP species 0.2 2.3.3 Outcome 0.333 0.0667 100 2.3.1 Management 0.333 0.0667 85 2.3.2 Information 0.333 0.0667 100 Habitats 0.2 2.4.3 Outcome 0.333 0.0667 80 2.4.1 Management 0.333 0.0667 80 2.4.2 Information 0.333 0.0667 90 Ecosystem 0.2 2.5.3 Outcome 0.333 0.0667 80 2.5.1 Management 0.333 0.0667 80 2.5.2 Information 0.333 0.0667 80 Three 1 Governance 0.5 3.1.13 Legal & customary framework 0.25 0.125 100 and policy 3.1.2 Consultation, roles & 0.25 0.125 95 3.1.3 Longresponsibilities term objectives 0.25 0.125 100 3.1.4 Incentives for sustainable fishing 0.25 0.125 80 Fishery specific 0.5 3.2. Fishery specific objectives 0.2 0.1 80 management 3.2.1 Decision making processes 0.2 0.1 80 system 3.2.2 Compliance & enforcement 0.2 0.1 100 3.2.43 Research plan 0.2 0.1 80 3.2.5 Management performance 0.2 0.1 90 evaluation

6.3 Summary of Conditions

Table 6.3: Summary of Conditions Condition Condition Performance Indicator number Information on by-catch species and ongoing evaluation of 1 2.2.3 changes in risk to these species.

6.4 Determination, Formal Conclusion and Agreement

The fishery attained a score of 80 or more against each of the MSC Principles and did not score less than 60 against any MSC Performance Indicator. It is therefore recommended that the Dutch Oyster Association Oyster Fisheries (as defined above) be certified according to the Marine Stewardship Council Principles and Criteria for Sustainable Fisheries.

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(REQUIRED FOR PCR)

The report shall include a formal statement as to the certification action taken by the CAB’s official decision-makers in response to the Determination recommendation.

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Appendices

Appendix 1 Scoring and Rationales

Appendix 1.1 Performance Indicator Scores and Rationale

Evaluation Table PI 1.1.1 The stock is at a level which maintains high productivity and has a low PI 1.1.1 probability of recruitment overfishing SG Issue Met? Justification/Rationale (Y/N) 60 a It is likely that the stock is above the point where recruitment would be impaired.

See 100 a)

80 a It is highly likely that the stock is above the point where recruitment would be impaired. See 100 a

b The stock is at or fluctuating around its target reference point. See 100 a

100 a There is a high degree of certainty that the stock is above the point where recruitment would be impaired. As there is no stock assessment, the Risk-Based Framework was used to evaluate the fisheries. As required for Principle 1, both SICA and PSA analyses were conducted. The outcome of the PSA analysis was a score of 94 for this PI. The exception to this is O edulis in Lake Grevelingen where the positive contribution of plot management to the age/size structure of the population results in a SICA score of 100.

b There is a high degree of certainty that the stock has been fluctuating around its target reference point, or has been above its target reference point, over recent years. See 100 a

See Appendix 1.2 References

Stock Status relative to Reference Points

Type of reference Current stock status Value of reference point point relative to reference point Target reference point n/a Limit reference point n/a OVERALL PERFORMANCE INDICATOR SCORE: C gigas Oosterschelde 94

OVERALL PERFORMANCE INDICATOR SCORE: C gigas Grevelingen 94

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The stock is at a level which maintains high productivity and has a low PI 1.1.1 probability of recruitment overfishing

OVERALL PERFORMANCE INDICATOR SCORE: O edulis Oosterschelde 94

OVERALL PERFORMANCE INDICATOR SCORE: O edulis Grevelingen 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 46 V3

Evaluation Table: PI 1.1.2

PI 1.1.2 Limit and target reference points are appropriate for the stock

Met? SG Issue Justification/Rationale (Y/N) 60 a Generic limit and target reference points are based on justifiable and reasonable practice appropriate for the species category. As the RBF is used for Principle 1, this PI scores a default 80 score.

80 a Reference points are appropriate for the stock and can be estimated.

b The limit reference point is set above the level at which there is an appreciable risk of impairing reproductive capacity.

c The target reference point is such that the stock is maintained at a level consistent with BMSY or some measure or surrogate with similar intent or outcome.

d Key low trophic level species, the target reference point takes into account the ecological role of the stock.

100 b The limit reference point is set above the level at which there is an appreciable risk of impairing reproductive capacity following consideration of precautionary issues.

c The target reference point is such that the stock is maintained at a level consistent with BMSY or some measure or surrogate with similar intent or outcome, or a higher level, and takes into account relevant precautionary issues such as the ecological role of the stock with a high degree of certainty.

References OVERALL PERFORMANCE INDICATOR SCORE: All Units of Certification 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 47 V3

Evaluation Table: PI 1.1.3

PI 1.1.3 Where the stock is depleted, there is evidence of stock rebuilding

Met? SG Issue Justification/Rationale (Y/N) 60 a Where stocks are depleted rebuilding strategies which have a reasonable expectation of success are in place. This PI is not applicable to this fishery.

b A rebuilding timeframe is specified for the depleted stock that is the shorter of 30 years or 3 times its generation time. For cases where 3 generations is less than 5 years, the rebuilding timeframe is up to 5 years.

c Monitoring is in place to determine whether they are effective in rebuilding the stock within a specified timeframe.

80 a Where stocks are depleted rebuilding strategies are in place.

b A rebuilding timeframe is specified for the depleted stock that is the shorter of 20 years or 2 times its generation time. For cases where 2 generations is less than 5 years, the rebuilding timeframe is up to 5 years.

c There is evidence that they are rebuilding stocks, or it is highly likely based on simulation modelling or previous performance that they will be able to rebuild the stock within a specified timeframe.

100 a Where stocks are depleted, strategies are demonstrated to be rebuilding stocks continuously and there is strong evidence that rebuilding will be complete within the specified timeframe.

b The shortest practicable rebuilding timeframe is specified which does not exceed one generation time for the depleted stock.

References OVERALL PERFORMANCE INDICATOR SCORE: All Units of Certification n/a

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 48 V3

Evaluation Table: PI 1.2.1

PI 1.2.1 There is a robust and precautionary harvest strategy in place

Met? SG Issue Justification/Rationale (Y/N) 60 a The harvest strategy is expected to achieve stock management objectives reflected in the target and limit reference points. See 80 a)

b The harvest strategy is likely to work based on prior experience or plausible argument. See 80 a)

c Monitoring is in place that is expected to determine whether the harvest strategy is working. See 80 b)

80 a Y The harvest strategy is responsive to the state of the stock and the elements of the harvest strategy work together towards achieving management objectives reflected in the target and limit reference points. The policy for all oyster fisheries is to maintain an economically viable fishery that respects the environment. This translates into a restricted number of licenses to fish managed plots and, for fisheries in the Oosterschelde to fish (subject to restrictions to protect mussel culture areas, environmentally sensitive areas and intertidal) on free ground, and regulations on the import of living shellfish. Elements of licence and plot management work together to achieve overall objectives.

Appropriate Assessments (AA) (including for the fishery on the free grounds in Oosterschelde) identified no effects of the fishery that would compromise the status of the European site. No further objectives were then identified.

b Y The harvest strategy may not have been fully tested but monitoring is in place and evidence exists that it is achieving its objectives. Strategy is not fully tested but the AA has identified no significant adverse effects, and fishery continues to be economically viable. IMARES now monitor oyster stocks on the free grounds in Oosterschelde, although only in intertidal areas. There is no monitoring in Grevelingen, but this fishery is restricted to a small area of managed plots.

100 a N The harvest strategy is responsive to the state of the stock and is designed to achieve stock management objectives reflected in the target and limit reference points. The strategy takes into account the maintenance of stocks (via plot management) but is not designed for stock management.

b N The performance of the harvest strategy has been fully evaluated and evidence exists to show that it is achieving its objectives including being clearly able to maintain stocks at target levels. Strategy not fully evaluated

d N The harvest strategy is periodically reviewed and improved as necessary. Elements of the harvest strategy are reviewed, but it is not reviewed as a single exercise. References Ministerie van LNV, 2004; Keus & Holstein, 2008; Brummelhuis et al. 2011.

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PI 1.2.1 There is a robust and precautionary harvest strategy in place

Met? SG Issue Justification/Rationale (Y/N) OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Evaluation Table: PI 1.2.2

PI 1.2.2 There are well defined and effective harvest control rules in place

Met? SG Issue Justification/Rationale (Y/N) 60 a Y Generally understood harvest rules are in place that are consistent with the harvest strategy and which act to reduce the exploitation rate as limit reference points are approached. See 80 a)

c Y There is some evidence that tools used to implement harvest control rules are appropriate and effective in controlling exploitation. See 80 c)

80 a Y Well defined harvest control rules are in place that are consistent with the harvest strategy and ensure that the exploitation rate is reduced as limit reference points are approached. Licenses are in place for: fishing for oyster, access to fishing grounds, nature conservation licence to fish on free grounds, rental agreement for plots. Licenses specify allowed activities.

The NOV Fishing Plan operationalises all of the licence conditions in a well-defined document. Oyster Association may also close all or part of the fishery under special circumstances. The status of the C. gigas population is of pest proportion and so limitations on catches are not of concern.

Nature license limits fishing to specific areas and requires reporting annually of landings of oyster and spat. Appropriate Assessment (currently 2009-Dec 2012) includes for an evaluation of effects of fishing in Oosterschelde on Natura 2000 site.

Rules are therefore well defined and are consistent with the harvest strategy in controlling exploitation as required.

b Y The selection of the harvest control rules takes into account the main uncertainties. The rules, expressed in licence controls have evolved in response to the changes in O. edulis and C. gigas populations and so have incorporated the main uncertainties.

c Y Available evidence indicates that the tools in use are appropriate and effective in achieving the exploitation levels required under the harvest control rules.

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PI 1.2.2 There are well defined and effective harvest control rules in place

Met? SG Issue Justification/Rationale (Y/N) For C. gigas, oyster are removed from an expanding population

For O. edulis, high mortality is expected (due to Bonamia), so these are removed prior to expected mortality but after spawning. Management of oyster grounds assists in maintaining the population. One management tool to control Bonamia is to maintain populations at low densities.

100 a

n/a

b N The design of the harvest control rules takes into account a wide range of uncertainties. It is not evidenced that a wide range of uncertainties have been considered.

c N Evidence clearly shows that the tools in use are effective in achieving the exploitation levels required under the harvest control rules. Evidence does not clearly show this.

Ministerie van LNV, 2008; Nederlandse Oestervereniging, 2012; Public Law References licence; Private Law Licence OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 51 V3

Evaluation Table: PI 1.2.3

PI 1.2.3 Relevant information is collected to support the harvest strategy

Met? SG Issue Justification/Rationale (Y/N) 60 a Y Some relevant information related to stock structure, stock productivity and fleet composition is available to support the harvest strategy.

See 80 a)

b Y Stock abundance and fishery removals are monitored and at least one indicator is available and monitored with sufficient frequency to support the harvest control rule. See 80 b)

80 a Y Sufficient relevant information related to stock structure, stock productivity, fleet composition and other data is available to support the harvest strategy. Populations on plots in both water bodies are well known. IMARES survey the extent of oyster beds on free grounds in Oosterschelde; productivity (carrying capacity) of Oosterschelde is being studied at present to feed into management of the Oosterschelde; fleet is very well known and monitored; a ‘Knowledge Group for oysters’ (Kenniskring Oesterkweek) involving collaboration between research institutes and industry has been set up to identify research requirements. b Y Stock abundance and fishery removals are regularly monitored at a level of accuracy and coverage consistent with the harvest control rule, and one or more indicators are available and monitored with sufficient frequency to support the harvest control rule. Catches from free grounds are reported and landings from free grounds and plots accurately recorded through the Oyster Association. c Y There is good information on all other fishery removals from the stock. There is no other fishery affecting the stock. A public allowance of 10kg per person (mostly from dikes), although this will be minor in relation to the overall stock. In Grevelingen, C. gigas are removed from some recreational areas in lake Grevelingen.

100 a N A comprehensive range of information (on stock structure, stock productivity, fleet composition, stock abundance, fishery removals and other information such as environmental information), including some that may not be directly related to the current harvest strategy, is available. Only limited information on stock abundance, stock structure and productivity

b N All information required by the harvest control rule is monitored with high frequency and a high degree of certainty, and there is a good understanding of inherent uncertainties in the information [data] and the robustness of assessment and management to this uncertainty. Uncertainties not well evaluated.

References Brummelhuis et al. 2011; Stakeholder meetings. OVERALL PERFORMANCE INDICATOR SCORE: All Units of Certification 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 52 V3

Evaluation Table: PI 1.2.4

PI 1.2.4 There is an adequate assessment of the stock status

Met? SG Issue Justification/Rationale (Y/N) 60 b The assessment estimates stock status relative to reference points. As the RBF is used for Principle 1, this PI scores a default 80 score.

c The assessment identifies major sources of uncertainty.

80 a The assessment is appropriate for the stock and for the harvest control rule.

c The assessment takes uncertainty into account.

e The assessment of stock status is subject to peer review.

100 a The assessment is appropriate for the stock and for the harvest control rule and takes into account the major features relevant to the biology of the species and the nature of the fishery.

c The assessment takes into account uncertainty and is evaluating stock status relative to reference points in a probabilistic way.

d The assessment has been tested and shown to be robust. Alternative hypotheses and assessment approaches have been rigorously explored.

e The assessment has been internally and externally peer reviewed.

References

OVERALL PERFORMANCE INDICATOR SCORE: All Units of Certification 80

Dutch Oyster Association Oyster Fishery Report page 53 V3

Evaluation Table: PI 2.1.1 The fishery does not pose a risk of serious or irreversible harm to the retained species PI 2.1.1 and does not hinder recovery of depleted retained species Met? SG Issue Justification/Rationale (Y/N) 60 a Y Main retained species are likely to be within biologically based limits (if not, go to scoring issue d below). See 100 a).

c Y If main retained species are outside the limits there are measures in place that are expected to ensure that the fishery does not hinder recovery and rebuilding of the depleted species. See 100 a)

d Y If the status is poorly known there are measures or practices in place that are expected to result in the fishery not causing the retained species to be outside biologically based limits or hindering recovery. See 100 a)

80 a Y Main retained species are highly likely to be within biologically based limits (if not, go to scoring issue c below). See 100 a)

c Y If main retained species are outside the limits there is a partial strategy of demonstrably effective management measures in place such that the fishery does not hinder recovery and rebuilding. See 100 a)

100 a Y There is a high degree of certainty that retained species are within biologically based limits and fluctuating around their target reference points. The only potential retained species might be the mussel Mytilus edulis or the razor shell Ensis sp taken in association with oyster on the free grounds. However, the fishing licence (for the fishery on the free grounds) states that it is obligatory to immediately return to the seawater all other shellfish than oysters, if they constitute >15% of the gross catch weight. The practicalities of handling such small amounts of other species mean that all bycatch is returned to the water. The fishery therefore has no retained species and scores 100 according to CR CB 3.2.1. b Y Target reference points are defined and retained species. See 100 a)

Stakeholder Meetings, Ministerie van LNV, 2008. References

OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 54 V3

Evaluation Table: PI 2.1.2 There is a strategy in place for managing retained species that is designed to PI 2.1.2 ensure the fishery does not pose a risk of serious or irreversible harm to retained species Met? SG Issue Justification/Rationale (Y/N) 60 a Y There are measures in place, if necessary, that are expected to maintain the main retained species at levels which are highly likely to be within biologically based limits, or to ensure the fishery does not hinder their recovery and rebuilding. see 80a b Y The measures are considered likely to work, based on plausible argument (e.g., general experience, theory or comparison with similar fisheries/species). see 80b 80 a Y There is a partial strategy in place, if necessary that is expected to maintain the main retained species at levels which are highly likely to be within biologically based limits, or to ensure the fishery does not hinder their recovery and rebuilding. There is a partial strategy for main retained species in that Nature Permit Article 11 requires release of any by-catch from the free grounds as quickly as possible. If catches exceed 15% of other bivalves, the entire catch must be released. The intense management of the plots means that there are no retained species from these areas. Both the Nb-permit and the fishery licence have restricting rules about the bycatch of shellfish other than oysters. b Y There is some objective basis for confidence that the partial strategy will work, based on some information directly about the fishery and/or species involved. The partial strategy is expected to work as no species other than oyster are landed. Practicalities of fishing, market forces and licence requirements together provide confidence that there would be no retained species. c Y There is some evidence that the partial strategy is being implemented successfully. Occasional inspections are carried out by the Ministry of EL&I, Inspection service (AID). Inspectorate confirms that compliance is good. PVis also check landings. 100 a N There is a strategy in place for managing retained species. There is not a strategy specifically for all bycatch species and so none of the 100 requirements are met. b N Testing supports high confidence that the strategy will work, based on information directly about the fishery and/or species involved.

c N There is clear evidence that the strategy is being implemented successfully.

d N There is some evidence that the strategy is achieving its overall objective.

Ministerie van LNV, 2008: Nb-licence art. 11; Fishery licence art. 8, References Stakeholder Meetings

Dutch Oyster Association Oyster Fishery Report page 55 V3

There is a strategy in place for managing retained species that is designed to PI 2.1.2 ensure the fishery does not pose a risk of serious or irreversible harm to retained species Met? SG Issue Justification/Rationale (Y/N) OVERALL PERFORMANCE INDICATOR SCORE: All Units of Certification 80

CONDITION NUMBER (if relevant):

Evaluation Table: PI 2.1.3 PI 2.1.3 Information on the nature and extent of retained species is adequate to determine the risk posed by the fishery and the effectiveness of the strategy to manage retained species Met? SG Issue Justification/Rationale (Y/N) 60 a Y Qualitative information is available on the amount of main retained species taken by the fishery. see 80a

b Y Information is adequate to qualitatively assess outcome status with respect to biologically based limits. see 80b c Y Information is adequate to support measures to manage main retained species. see 80c 80 a Y Qualitative information and some quantitative information are available on the amount of main retained species taken by the fishery. Qualitative and quantitative information is available from P Vis monitoring of landings and occasional inspections by the AID (carrying out fishery inspections on behalf of the Ministry of EL&I). This is supported by qualitative information from the Dutch Oyster Association b Y Information is sufficient to estimate outcome status with respect to biologically based limits. Information is adequate to identify that there are no retained species. c Y Information is adequate to support a partial strategy to manage main retained species. The partial strategy effectively results in no retained species. This is monitored. d Y Sufficient data continue to be collected to detect any increase in risk level (e.g. due to changes in the outcome indicator score or the operation of the fishery or the effectiveness of the strategy) Inspections of catches at sea and landings continue via AID and P Vis.

100 a N Accurate and verifiable information is available on the catch of all retained species and the consequences for the status of affected populations. As above, all catches are not monitored and there is not a comprehensive strategy for ALL potentially retained species and so none of the SG 100 requirements are met. b N Information is sufficient to quantitatively estimate outcome status with a high degree of certainty.

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PI 2.1.3 Information on the nature and extent of retained species is adequate to determine the risk posed by the fishery and the effectiveness of the strategy to manage retained species Met? SG Issue Justification/Rationale (Y/N) c N Information is adequate to support a comprehensive strategy to manage retained species, and evaluate with a high degree of certainty whether the strategy is achieving its objective.

d N Monitoring of retained species is conducted in sufficient detail to assess ongoing mortalities to all retained species.

References Nb-licence art. 11 Fishery licence art. 8, Stakeholder Meetings OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 57 V3

Evaluation Table: PI 2.2.1 The fishery does not pose a risk of serious or irreversible harm to the bycatch PI 2.2.1 species or species groups and does not hinder recovery of depleted bycatch species or species groups Met? SG Issue Justification/Rationale (Y/N) 60 a Y Main bycatch species are likely to be within biologically based limits (if not, go to scoring issue b below).

b Y If main bycatch species are outside biologically based limits there are mitigation measures in place that are expected to ensure that the fishery does not hinder recovery and rebuilding.

c Y If the status is poorly known there are measures or practices in place that are expected to result in the fishery not causing the bycatch species to be outside biologically based limits or hindering recovery.

80 a Y Main bycatch species are highly likely to be within biologically based limits (if not, go to scoring issue b below).

b Y If main bycatch species are outside biologically based limits there is a partial strategy of demonstrably effective mitigation measures in place such that the fishery does not hinder recovery and rebuilding.

100 a Y There is a high degree of certainty that bycatch species are within biologically based limits. Owing to a lack of information on the effects of the fishery on bycatch, the RBF was used to evaluate this PI.

References OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 58 V3

Evaluation Table: PI 2.2.2 There is a strategy in place for managing bycatch that is designed to ensure PI 2.2.2 the fishery does not pose a risk of serious or irreversible harm to bycatch populations Met? SG Issue Justification/Rationale (Y/N) 60 a Y There are measures in place, if necessary, which are expected to maintain main bycatch species at levels which are highly likely to be within biologically based limits or to ensure that the fishery does not hinder their recovery. See 80 a)

b Y The measures are considered likely to work, based on plausible argument (e.g. general experience, theory or comparison with similar fisheries/species). See 80 b)

80 a Y There is a partial strategy in place, if necessary, for managing bycatch species at levels which are highly likely to be within biologically based limits or to ensure that the fishery does not hinder their recovery. The evidence provided in relation to PI 2.2.1 above strongly suggests that the fishery would not affect bycatch species. In addition, any bycatch material is immediately returned to the sea. As such, a partial strategy is not considered necessary (ref CR CB 3.3). b Y There is some objective basis for confidence that the partial strategy will work, based on some information directly about the fishery and/or the species involved. As for a) above, a partial strategy is not considered necessary for this fishery. c Y There is some evidence that the partial strategy is being implemented successfully. As for a) above. 100 a N There is a strategy in place for managing and minimising bycatch. There is not a strategy specifically for all bycatch species and so none of the 100 requirements are met. b N Testing supports high confidence that the strategy will work, based on information directly about the fishery and/or species involved.

c N There is clear evidence that the strategy is being implemented successfully.

d N There is some evidence that the strategy is achieving its objective.

References Nb-licence art. 11 Fishery licence art. 8, Stakeholder Meetings; Keus & Holstein, 2008 OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 59 V3

Evaluation Table: PI 2.2.3 Information on the nature and the amount of bycatch is adequate to determine PI 2.2.3 the risk posed by the fishery and the effectiveness of the strategy to manage bycatch Met? SG Issue Justification/Rationale (Y/N) 60 a Y Qualitative information is available on the main bycatch species affected by the fishery. Although not documented, there is qualitative information on bycatch species affected by the fishery within the Dutch Oyster Association and IMARES b n/a Information is adequate to broadly understand outcome status with respect to biologically based limits Scoring issue not scored as RBF used to score PI 2.2.1 c Y Information is adequate to support measures to manage bycatch. There are quite strict rules that bycatch (of shellfish) should be released; management of the plots reduces the bycatch 80 a N Qualitative information and some quantitative information are available on the amount of main bycatch species affected by the fishery. Information on the bycatch in this fishery is not available b n/a Information is sufficient to estimate outcome status with respect to biologically based limits. [Scoring issue need not be scored when RBF used to score PI 2.2.1] c Y Information is adequate to support a partial strategy to manage main bycatch species. It is known that there is a low level of bycatch – leading to a strategy requiring return of material to sea as soon as possible. It is known that there is very little bycatch on culture plots. Removal experiment showed that effects of removal of oysters is temporary, with reversible effect. d N Sufficient data continue to be collected to detect any increase in risk to main bycatch species (e.g., due to changes in the outcome indicator scores or the operation of the fishery or the effectively of the strategy). See 80 a)

100 a N Accurate and verifiable information is available on the amount of all bycatch and the consequences for the status of affected populations.

b n/a Information is sufficient to quantitatively estimate outcome status with respect to biologically based limits with a high degree of certainty. n/a

c N Information is adequate to support a comprehensive strategy to manage bycatch, and evaluate with a high degree of certainty whether a strategy is achieving its objective.

d N Monitoring of bycatch data is conducted in sufficient detail to assess ongoing mortalities to all bycatch species.

References Wijsman et al., 2008

Dutch Oyster Association Oyster Fishery Report page 60 V3

Information on the nature and the amount of bycatch is adequate to determine PI 2.2.3 the risk posed by the fishery and the effectiveness of the strategy to manage bycatch Met? SG Issue Justification/Rationale (Y/N) OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 65

CONDITION NUMBER (if relevant): 1

Dutch Oyster Association Oyster Fishery Report page 61 V3

Evaluation Table: PI 2.3.1 The fishery meets national and international requirements for the protection of ETP species PI 2.3.1 The fishery does not pose a risk of serious or irreversible harm to ETP species and does not hinder recovery of ETP species Met? SG Issue Justification/Rationale (Y/N) 60 a Y Known effects of the fishery are likely to be within limits of national and international requirements for protection of ETP species. see 100a

b Y Known direct effects are unlikely to create unacceptable impacts to ETP species.

see 100b

80 a Y The effects of the fishery are known and are highly likely to be within limits of national and international requirements for protection of ETP species. see 100a

b Y Direct effects are highly unlikely to create unacceptable impacts to ETP species.

see 100b

c Y Indirect effects have been considered and are thought to be unlikely to create unacceptable impacts. see 100c

100 a Y There is a high degree of certainty that the effects of the fishery are within limits of national and international requirements for protection of ETP species. Such certainty is provided, for both waterbodies, by the regularly updated Appropriate Assessment. O edulis is also subject to protection; however, the presence of the flat oyster in Grevelingen is maintained by the culture of this species in this ecosystem, which enhances the settlement of oyster spat and harvests the oysters before Bonamia mortality causes their loss.

b Y There is a high degree of confidence that there are no significant detrimental direct effects of the fishery on ETP species. Direct effects would be direct mortality due to interactions with fishing gear. No such interactions would occur with this fishery. Zostera noltii is present in the Kom within the Oosterschelde (Z noltii protected under flora and fauna law) but does not overlap with culture plots and (within the Oosterschelde) fishing is not allowed in known Zostera beds or littoral areas. c Y There is a high degree of confidence that there are no significant detrimental indirect effects of the fishery on ETP species. Disturbance of seabirds (prevented by a 500m exclusion zone around roosts) and seals (prevented by a 1500m exclusion zone around haul-outs) is controlled by licence conditions, and incorporated in fishing plan. References Nb-licence art. 11 Fishery licence art. 8, Stakeholder Meetings; EFTAS 2010 OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 62 V3

Evaluation Table: PI 2.3.2 The fishery has in place precautionary management strategies designed to:  Meet national and international requirements; PI 2.3.2  Ensure the fishery does not pose a risk of serious harm to ETP species;  Ensure the fishery does not hinder recovery of ETP species; and  Minimise mortality of ETP species. Met? SG Issue Justification/Rationale (Y/N) 60 a Y There are measures in place that minimise mortality, and are expected to be highly likely to achieve national and international requirements for the protection of ETP species. see 80a

b Y The measures are considered likely to work, based on plausible argument (e.g., general experience, theory or comparison with similar fisheries/species). see 80b

80 a Y There is a strategy in place for managing the fishery’s impact on ETP species, including measures to minimise mortality, that is designed to be highly likely to achieve national and international requirements for the protection of ETP species. See 100 a).

b Y There is an objective basis for confidence that the strategy will work, based on information directly about the fishery and/or the species involved. The effectiveness of the strategy and measures contained therein is evaluated through a regular Appropriate Assessment of the fisheries (as a plan or project under the EC Habitats Directive). This is based on information on both the fishery and the species involved. c Y There is evidence that the strategy is being implemented successfully. Inspections are carried out by AID, supported by black-box data. Zostera is expanding (EFTAS 2010). The number of seals in the Delta area is still lower than the objective, but the cause of this is not the oyster fishery. 100 a Y There is a comprehensive strategy in place for managing the fishery’s impact on ETP species, including measures to minimise mortality that is designed to achieve above national and international requirements for the protection of ETP species. Management plans for the European sites represent a strategy for management of fishing impacts. This, and permit conditions, are operationalised through the Fishing Plan. Mortality and indirect effects of disturbance will be prevented by this strategy (indirect effects of disturbance are part of a comprehensive strategy to address all impacts). Potential effects on Zostera beds are also avoided. b N The strategy is mainly based on information directly about the fishery and/or species involved, and a quantitative analysis supports high confidence that the strategy will work. While the strategy is based on the fishery and species involved, no quantitative analysis has been carried out (nor would be expected given the low risks involved). c N There is clear evidence that the strategy is being implemented successfully. As above d N There is evidence that the strategy is achieving its objective.

Dutch Oyster Association Oyster Fishery Report page 63 V3

The fishery has in place precautionary management strategies designed to:  Meet national and international requirements; PI 2.3.2  Ensure the fishery does not pose a risk of serious harm to ETP species;  Ensure the fishery does not hinder recovery of ETP species; and  Minimise mortality of ETP species. Met? SG Issue Justification/Rationale (Y/N) As above References Beheerplan Natura 2000 Deltawateren (in prep.); Globale en Nadere effectenanalyse (Rijkswaterstaat and Min. EL&I, 2011). EFTAS, 2011. Keus & Holstein, 2008. OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 85

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 64 V3

Evaluation Table: PI 2.3.3 Relevant information is collected to support the management of fishery impacts on ETP species including: PI 2.3.3  Information for the development of the management strategy;  Information to assess the effectiveness of the management strategy; and  Information to determine the outcome status of ETP species. Met? SG Issue Justification/Rationale (Y/N) 60 a Y Information is sufficient to qualitatively estimate the fishery related mortality of ETP species. See 100 a)

b Y Information is adequate to broadly understand the impact of the fishery on ETP species. See 100 b)

c Y Information is adequate to support measures to manage the impacts on ETP species.

See 100 c)

80 a Y Sufficient data are available to allow fishery related mortality and the impact of fishing to be quantitatively estimated for ETP species. See 100 a)

b Y Information is sufficient to determine whether the fishery may be a threat to protection and recovery of the ETP species. See 100 b)

c Y Information is sufficient to measure trends and support a full strategy to manage impacts on ETP species. See 100 c)

100 a Y Information is sufficient to quantitatively estimate outcome status of ETP species with a high degree of certainty. Good information is available on the status of seal and bird populations in both Grevelingen and Oosterschelde.

b Y Accurate and verifiable information is available on the magnitude of all impacts, mortalities and injuries and the consequences for the status of ETP species. Information on the operation of the fishery if sufficient to verify that there would not be mortality or injury to seal or bird populations from fishing operations. Fishing is not allowed in Zostera beds, and this can be verified by at-sea inspections and VMS tracks.

c Y Information is adequate to support a comprehensive strategy to manage impacts, minimise mortality and injury of ETP species, and evaluate with a high degree of certainty whether a strategy is achieving its objectives. Information provided by Appropriate Assessment is adequate to support management of the European Sites. This information would provide a high degree of certainty on the effectiveness of the fishery plan.

References Strucker et al., 2012, EFTAS 2011; Keus & Holstein, 2008.

Dutch Oyster Association Oyster Fishery Report page 65 V3

Relevant information is collected to support the management of fishery impacts on ETP species including: PI 2.3.3  Information for the development of the management strategy;  Information to assess the effectiveness of the management strategy; and  Information to determine the outcome status of ETP species. Met? SG Issue Justification/Rationale (Y/N) OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 66 V3

Evaluation Table: PI 2.4.1

The fishery does not cause serious or irreversible harm to habitat structure, PI 2.4.1 considered on a regional or bioregional basis and function Met? SG Issue (Y/P/ Justification/Rationale N) 60 a Y The fishery is unlikely to reduce habitat structure and function to a point where there would be serious or irreversible harm. See 100 a

80 a Y The fishery is highly unlikely to reduce habitat structure and function to a point where there would be serious or irreversible harm. An experimental removal of oysters, and investigation of the effects of this (Wijsman et al., 2008) concluded that fishing of oyster beds does not lead to irreversible harm to the habitats concerned. Recovery of the oysterbed takes 3-6 yrs. The areas of oyster plots are managed for this purpose and represent extremely small proportions of total habitat in the two water bodies (in Oosterschelde, fishing takes place over free grounds and plots which total <15% of total oyster distribution; plots in Grevelingen comprise only 5% of the total area). Fishing on the free ground in the Oosterschelde is done by using oyster dredges which have low impact on the seabed. Furthermore, the areas where dredging is permitted are restricted; there are closed areas and it is not allowed to dredge on the intertidal flats, except in the Kom of Oosterschelde, where the culture plots are also located. 100 a N There is evidence that the fishery is highly unlikely to reduce habitat structure and function to a point where there would be serious or irreversible harm. Evidence has not been provided, however, on effects on all habitat types.

References Wijsman et al., 2008 OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 67 V3

Evaluation Table: PI 2.4.2 There is a strategy in place that is designed to ensure the fishery does not PI 2.4.2 pose a risk of serious or irreversible harm to habitat types Met? SG Issue Justification/Rationale (Y/N) 60 a Y There are measures in place, if necessary, that are expected to achieve the Habitat Outcome 80 level of performance. See 80 a)

b Y The measures are considered likely to work, based on plausible argument (e.g. general experience, theory or comparison with similar fisheries/habitats). See 80 b)

80 a Y There is a partial strategy in place, if necessary, that is expected to achieve the Habitat Outcome 80 level of performance or above. Elements within the fishing plan and other management measures for the Natura 2000 sites comprise a partial strategy that would be expected to achieve the SG 80 outcome. These include the clear identification and marking of oyster plots in the Oosterschelde and Grevelingen, permit requirements to fish on free grounds, restrictions on fishing in closed areas, mussel beds, Zostera beds and intertidal areas in the Oosterschelde (where a free-fishery occurs). b Y There is some objective basis for confidence that the partial strategy will work, based on information directly about the fishery and/or habitats involved. Studies have determined that oyster fishing does not have irreversible effects on habitat. The restriction to fishing in oyster plots in Grevelingen, and the extent of closed areas and other restriction in the Oosterschelde provide confidence that the partial strategy will work effectively. c Y There is some evidence that the partial strategy is being implemented successfully. Evidence of effective application of the partial strategy is provided by the use of VMS (black-box) on board vessels that records the dredge tracks. The fishing plan 2012 (Visplan) of the NOV describes the procedures for reading out the black box tracks and penalties if fishing occurred in areas where it was not allowed. Intertidal areas within the Oosterschelde, and features of nature conservation importance are monitored.

100 a N There is a strategy in place for managing the impact of the fishery on habitat types. There is no specific strategy to manage impacts on habitat within the fishery; accordingly, no SG 100 requirements are met.

b N Testing supports high confidence that the strategy will work, based on information directly about the fishery and/or habitats involved.

c N There is clear evidence that that strategy is being implemented successfully.

d N There is some evidence that the strategy is achieving its objective.

Dutch Oyster Association Oyster Fishery Report page 68 V3

There is a strategy in place that is designed to ensure the fishery does not PI 2.4.2 pose a risk of serious or irreversible harm to habitat types Met? SG Issue Justification/Rationale (Y/N)

References Strucker et al., 2011; Nederlandse Oestervisserij, 2012; Brummelhuis et al., 2011. OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 69 V3

Evaluation Table: PI 2.4.3 Information is adequate to determine the risk posed to habitat types by the fishery and PI 2.4.3 the effectiveness of the strategy to manage impacts on habitat types Met? SG Issue Justification/Rationale (Y/N) 60 a Y There is basic understanding of the types and distribution of main habitats in the area of the fishery. see 80a

b Y Information is adequate to broadly understand the nature of the main impacts of gear use on the main habitats, including spatial overlap of habitat with fishing gear. see 80b

80 a Y The nature, distribution and vulnerability of all main habitat types in the fishery are known at a level of detail relevant to the scale and intensity of the fishery. See 100 a)

b Y Sufficient data are available to allow the nature of the impacts of the fishery on habitat types to be identified and there is reliable information on the spatial extent of interaction, and the timing and location of use of the fishing gear. Effects of fishing have been investigated through an oyster removal experiment. Locations of the culture plots are exactly known, fishing in the free grounds is at a much lower level and is monitored by using the black-box system and by fishery inspectorate observations. c Y Sufficient data continue to be collected to detect any increase in risk to habitat (e.g. due to changes in the outcome indicator scores or the operation of the fishery or the effectiveness of the measures). The monitoring measures described above are continuing, as are regular updates of the Appropriate Assessment of the fisheries. A management plan is in place for both areas (as Natura 2000 sites). 100 a Y The distribution of habitat types is known over their range, with particular attention to the occurrence of vulnerable habitat types. The nature of habitats in both Oosterschelde and Grevelingen is known in some detail, particularly in relation to oyster plots (especially as in Oosterschelde this is a Natura 2000 feature). The only vulnerable habitat present (in Oosterschelde) is Zostera beds, which are clearly identified.

b N The physical impacts of the gear on the habitat types have been quantified fully.

An experiment was conducted on oyster removal, but this is a one-off situation. Full quantification does not occur.

c Y Changes in habitat distributions over time are measured. As above

References Wijsman et al., 2008; Appropriate Assessment 2008 OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 90

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 70 V3

Evaluation Table: PI 2.5.1 The fishery does not cause serious or irreversible harm to the key elements of PI 2.5.1 ecosystem structure and function Met? SG Issue (Y/P/ Justification/Rationale N) 60 a Y The fishery is unlikely to disrupt the key elements underlying ecosystem structure and function to a point where there would be a serious or irreversible harm.

See 80

80 a Y The fishery is highly unlikely to disrupt the key elements underlying ecosystem structure and function to a point where there would be a serious or irreversible harm. The Pacific oyster has very successfully colonised both the Oosterschelde and Grevelingen; it cannot now be eradicated by fishing activities and the fishery serves to partly manage the C gigas population and sustain the O edulis population in Grevelingen. The fishery would not compromise the effects of oyster beds in stabilising intertidal areas.

Measures are in place to limit further introductions of species associated with shellfish culture in both water bodies. 100 a N There is evidence that the fishery is highly unlikely to disrupt the key elements underlying ecosystem structure and function to a point where there would be a serious or irreversible harm. While the points above can be concluded on the basis of expert judgement, provision of direct evidence of these points would be extremely difficult and expensive to obtain.

References Troost, 2012

OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 71 V3

Evaluation Table: PI 2.5.2 There are measures in place to ensure the fishery does not pose a risk of PI 2.5.2 serious or irreversible harm to ecosystem structure and function Met? SG Issue Justification/Rationale (Y/N) 60 a Y There are measures in place, if necessary.

See 80 a)

b Y The measures take into account potential impacts of the fishery on key elements of the ecosystem. See 80 b)

c Y The measures are considered likely to work, based on plausible argument (e.g., general experience, theory or comparison with similar fisheries/ecosystems). See 80 c)

80 a Y There is a partial strategy in place, if necessary. The ecosystems in both the Oosterschelde and Grevelingen are both still in state of flux following civil engineering works and their total or partial exclusion from the sea. This is having several effects including the slumping of intertidal beds into deeper channels; oyster beds may play a stabilising role reducing this phenomenon.

Other than the issues discussed above, the only ecosystem interaction to be managed is the potential for further introductions of exotic species. The live import of oysters and other bivalve molluscs to Oosterschelde is now regulated with licences, based on a policy document of 2003 and partial adaptations in 2004. Currently, the policy is in revision and the latest version is not yet published. The current best practice can be derived from a recent verdict of the Raad van State (February 2012), which allows the import of shellfish from Irish and UK waters with the application of a shellfish import protocol (Gittenberger, 2010). Introductions into Grevelingen are not permitted. b Y The partial strategy takes into account available information and is expected to restrain impacts of the fishery on the ecosystem so as to achieve the Ecosystem Outcome 80 level of performance. Information on potential species and routes of introduction (into the Oosterschelde) is available and effects associated with this fishery are expected to be adequately controlled (noting, however, that several other potential routes of transmission remain).

c Y The partial strategy is considered likely to work, based on plausible argument (e.g., general experience, theory or comparison with similar fisheries/ecosystems).

Dutch Oyster Association Oyster Fishery Report page 72 V3

There are measures in place to ensure the fishery does not pose a risk of PI 2.5.2 serious or irreversible harm to ecosystem structure and function Met? SG Issue Justification/Rationale (Y/N) As above, the partial strategy is expected to work in relation to the fishery under assessment, this was recently confirmed by a judgement of the Raad van State (February 2012), which allows the import of shellfish from Irish and UK waters with the application of a shellfish import protocol. As above, it is noted that other sources of introductions remain (e.g. ballast water) and new species continue to appear, although their effects on ecosystem structure and function is variable.

d Y There is some evidence that the measures comprising the partial strategy are being implemented successfully. Fishers are aware of restrictions on import of shellfish and the issue has been reviewed by the Raad van State. 100 a N There is a strategy that consists of a plan, in place. While the measures described above comprise a partial strategy, there does not appear to be a comprehensive strategy on biosecurity; none of the SG100 requirements are met, therefore.

b N The strategy, which consists of a plan, contains measures to address all main impacts of the fishery on the ecosystem, and at least some of these measures are in place. The plan and measures are based on well- understood functional relationships between the fishery and the Components and elements of the ecosystem.

This plan provides for development of a full strategy that restrains impacts on the ecosystem to ensure the fishery does not cause serious or irreversible harm.

c N The measures are considered likely to work based on prior experience, plausible argument or information directly from the fishery/ecosystems involved.

d N There is evidence that the measures are being implemented successfully.

References Gittenberger, 2010; Raad van State (February 2012), OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 73 V3

Evaluation Table: PI 2.5.3

PI 2.5.3 There is adequate knowledge of the impacts of the fishery on the ecosystem

Met? SG Issue Justification/Rationale (Y/N) 60 a Y Information is adequate to identify the key elements of the ecosystem (e.g., trophic structure and function, community composition, productivity pattern and biodiversity). See 80 a)

b Y Main impacts of the fishery on these key ecosystem elements can be inferred from existing information, and have not been investigated in detail. See 80 b)

80 a Y Information is adequate to broadly understand the key elements of the ecosystem. As detailed in Section 3.4.6, there is substantial information on the ecosystem parameters in both the Oosterschelde and Lake Grevelingen, including influences on primary productivity (in the Oosterschelde).

b Y Main impacts of the fishery on these key ecosystem elements can be inferred from existing information and some have been investigated in detail. The fishery will have extremely minor effects on ecosystem structure and function, especially given the spread of C gigas within both systems. The primary productivity within the Oosterschelde has been specifically investigated, as have the types and biomass of introduced species.

c Y The main functions of the Components (i.e., target, Bycatch, Retained and ETP species and Habitats) in the ecosystem are known. As above, there is a substantial body of knowledge on ecosystem functions within both systems.

d Y Sufficient information is available on the impacts of the fishery on these Components to allow some of the main consequences for the ecosystem to be inferred. As above, the main effects of the fishery can be readily inferred as being minor.

e Y Sufficient data continue to be collected to detect any increase in risk level (e.g., due to changes in the outcome indicator scores or the operation of the fishery or the effectiveness of the measures). The extent of the fishery is very closely monitored; the distribution of oysters in the intertidal is also monitored. Other data collection relates to the conservation status of the European sites. Such information would detect any increases in risk level associated with the fishery.

100 b N Main interactions between the fishery and these ecosystem elements can be inferred from existing information, and have been investigated.

Dutch Oyster Association Oyster Fishery Report page 74 V3

PI 2.5.3 There is adequate knowledge of the impacts of the fishery on the ecosystem

Met? SG Issue Justification/Rationale (Y/N) Given the low significance of the fishery in ecosystem structure and function in both systems, specific studies associated with the fishery are few. None of the SG100 requirements are met, therefore.

c N The impacts of the fishery on target, Bycatch and ETP species are identified and the main functions of these Components in the ecosystem are understood.

d N Sufficient information is available on the impacts of the fishery on the Components and elements to allow the main consequences for the ecosystem to be inferred.

e N Information is sufficient to support the development of strategies to manage ecosystem impacts.

Troost, 2012; Brummelhuis et al. 2011 References

OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 75 V3

Evaluation Table: PI 3.1.1 The management system exists within an appropriate legal and/or customary framework which ensures that it:  Is capable of delivering sustainable fisheries in accordance with MSC Principles 1 PI 3.1.1 and 2;  Observes the legal rights created explicitly or established by custom of people dependent on fishing for food or livelihood; and  Incorporates an appropriate dispute resolution framework. Met? SG Issue Justification/Rationale (Y/N) 60 a Y The management system is generally consistent with local, national or international laws or standards that are aimed at achieving sustainable fisheries in accordance with MSC Principles 1 and 2. Relevant International Laws have been transcribed into National Law; perhaps most notable in this case is the EC Habitats Directive which is implemented in the Nb- wet. The management system is consistent with both National and International Laws. These laws are aimed at sustainable fishing and maintaining the ecological status of the Oosterschelde and Grevelingen.

b Y The management system incorporates or is subject by law to a mechanism for the resolution of legal disputes arising within the system. See 100 b)

c Y Although the management authority or fishery may be subject to continuing court challenges, it is not indicating a disrespect or defiance of the law by repeatedly violating the same law or regulation necessary for the sustainability of the fishery. See 100 c)

d Y The management system has a mechanism to generally respect the legal rights created explicitly or established by custom of people dependent on fishing for food or livelihood in a manner consistent with the objectives of MSC Principles 1 and 2. See 100 d)

80 b Y The management system incorporates or is subject by law to a transparent mechanism for the resolution of legal disputes which is considered to be effective in dealing with most issues and that is appropriate to the context of the fishery. See 100 b)

c Y The management system or fishery is attempting to comply in a timely fashion within binding judicial decisions arising from any legal challenges. See 100 c)

d Y The management system has a mechanism to observe the legal rights created explicitly or established by custom of people dependent on fishing for food or livelihood in a manner consistent with the objectives of MSC Principles 1 and 2. See 100 d)

100 b Y The management system incorporates or subject by law to a transparent mechanism for the resolution of legal disputes that is appropriate to the context of the fishery and has been tested and proven to be effective.

Dutch Oyster Association Oyster Fishery Report page 76 V3

The management system exists within an appropriate legal and/or customary framework which ensures that it:  Is capable of delivering sustainable fisheries in accordance with MSC Principles 1 PI 3.1.1 and 2;  Observes the legal rights created explicitly or established by custom of people dependent on fishing for food or livelihood; and  Incorporates an appropriate dispute resolution framework. Met? SG Issue Justification/Rationale (Y/N) Disputes are first addressed within NOV, including analysis of black-box data. Further disputes may be addressed at local level or national (Ministry) level. Details of dispute resolution mechanisms are freely available. At the ultimate level, disputes may be taken to National and EU courts.

Mechanisms are entirely appropriate to the context of the fishery and have been tested at all levels and proven to be effective (from inspection of VMS data in a dispute over access to plots, viewed by the assessment team, to European Court decisions on Dutch application of the Habitats Directive – tested in respect of fishery management in the Waddenzee).

c Y The management system or fishery acts proactively to avoid legal disputes or rapidly implements binding judicial decisions arising from legal challenges. The management system includes a broad consultative process, which would minimise the risk of legal disputes. Binding judicial decisions are rapidly implemented. d Y The management system has a mechanism to formally commit to the legal rights created explicitly or established by custom of people dependent on fishing for food and livelihood in a manner consistent with the objectives of MSC Principles 1 and 2. Legal rights to fish are contained within fishing permits, which may be transferred, and protected by legislation. The issuance of permits, and restrictions associated with these, are designed to protect the resource and nature conservation status of the waterbodies.

References Reglement Visplan 2012; Public Law licence; Private Law Licence OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 77 V3

Evaluation Table: PI 3.1.2 The management system has effective consultation processes that are open to interested and affected parties. PI 3.1.2 The roles and responsibilities of organisations and individuals who are involved in the management process are clear and understood by all relevant parties Met? SG Issue Justification/Rationale (Y/N) 60 a Y Organisations and individuals involved in the management process have been identified. Functions, roles and responsibilities are generally understood.

See 100 a)

b Y The management system includes consultation processes that obtain relevant information from the main affected parties, including local knowledge, to inform the management system. See 100 b)

80 a Y Organisations and individuals involved in the management process have been identified. Functions, roles and responsibilities are explicitly defined and well understood for key areas of responsibility and interaction. See 100 a)

c Y The consultation process provides opportunity for all interested and affected parties to be involved. Consultation provides opportunities for input by all affected parties.

100 a Y Organisations and individuals involved in the management process have been identified. Functions, roles and responsibilities are explicitly defined and well understood for key areas of responsibility and interaction. All organisations and individuals engaged in management of these fisheries are clearly identified, along with their roles and responsibilities. The key activity is the formulation of the annual Fishing Plan; organisation and individuals involved in this are clearly defined. Organisations such as AID are well informed on the requirements of the Fishing Plan.

b Y The management system includes consultation processes that regularly seek and accept relevant information, including local knowledge. The management system demonstrates consideration of the information and explains how it is used or not used. Annual reviews of the Fishing Plan specifically involves input from fishermen and others (e.g. through the Appropriate Assessment process).

c N The consultation process provides opportunity and encouragement for all interested and affected parties to be involved, and facilitates their effective engagement.

Dutch Oyster Association Oyster Fishery Report page 78 V3

The management system has effective consultation processes that are open to interested and affected parties. PI 3.1.2 The roles and responsibilities of organisations and individuals who are involved in the management process are clear and understood by all relevant parties Met? SG Issue Justification/Rationale (Y/N) While consultation provides opportunities for input by all affected parties, no evidence was provided for active facilitation of such inputs, e.g. from NGOs.

Stakeholder Meetings, Reglement Visplan 2012 References

OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 95

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 79 V3

Evaluation Table: PI 3.1.3 The management policy has clear long-term objectives to guide decision- PI 3.1.3 making that are consistent with MSC Principles and Criteria, and incorporates the precautionary approach Met? SG Issue (Y/P/ Justification/Rationale N) 60 a Y Long-term objectives to guide decision-making, consistent with the MSC Principles and Criteria and the precautionary approach, are implicit within management policy

See 100

80 a Y Clear long-term objectives that guide decision-making, consistent with MSC Principles and Criteria and the precautionary approach are explicit within management policy. See 100

100 a Y Clear long-term objectives that guide decision-making, consistent with MSC Principles and Criteria and the precautionary approach, are explicit within and required by management policy. Policy for the oyster fishery is to maintain an economically viable fishery that respects the environment. This policy may not conflict with European conservation obligations under e.g. the Habitats Directive. Decision making must therefore respect both viability and environmental effect.

References Reglement Visplan 2012 OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 80 V3

Evaluation Table: PI 3.1.4 The management system provides economic and social incentives for PI 3.1.4 sustainable fishing and does not operate with subsidies that contribute to unsustainable fishing Met? SG Issue (Y/P/ Justification/Rationale N) 60 a Y The management system provides for incentives that are consistent with achieving the outcomes expressed by MSC Principles 1 and 2. See 80

80 a Y The management system provides for incentives that are consistent with achieving the outcomes expressed by MSC Principles 1 and 2, and seeks to ensure that perverse incentives do not arise. The majority of fishing activity takes place on licensed plots which fishermen lease on a commercial basis and effectively ‘cultivate’ to maximise returns. In Oosterschelde, this is supplemented by fishing on free grounds, which is carried out according to the fishing plan and is closely inspected. No subsidies are in place that would compromise sustainability of the fishery. Fishermen are also strongly encouraged (e.g. by the fish board Productschap Vis) to develop better methods of cultivating oysters to maximise returns while minimising environmental effects.

100 a N The management system provides for incentives that are consistent with achieving the outcomes expressed by MSC Principles 1 and 2, and explicitly considers incentives in a regular review of management policy or procedures to ensure they not contribute to unsustainable fishing practices. No evidence was presented of regular reviews (e.g. annual develop of Fishing Plan) which explicitly consider incentives.

References Reglement Visplan 2012, Stakeholder Meetings OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 81 V3

Evaluation Table: PI 3.2.1 The fishery has clear, specific objectives designed to achieve the outcomes PI 3.2.1 expressed by MSC’s Principles 1 and 2 Met? SG Issue (Y/P Justification/Rationale N) 60 a Y Objectives, which are broadly consistent with achieving the outcomes expressed by MSC’s Principles 1 and 2, are implicit within the fishery’s management system.

See 80

80 a Y Short and long-term objectives, which are consistent with achieving the outcomes expressed by MSC’s Principles 1 and 2, are explicit within the fishery’s management system. Given the nature of the fishery (i.e. based on cultivation of plots leased by individual fishers), the Shellfish Policy and subsequent objectives for the oyster fishery (to maintain an economically viable fishery that respects the environment) represents both short and long-term objectives. These objectives are reflected in the development and review of the Fishing Plan.

100 a N Well defined and measurable short and long-term objectives, which are demonstrably consistent with achieving the outcomes expressed by MSC’s Principles 1 and 2, are explicit within the fishery’s management system. Objectives, being general in nature are neither well defined nor measurable, in this sense.

Shellfish Policy Document References

OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 82 V3

Evaluation Table: PI 3.2.2 The fishery-specific management system includes effective decision-making PI 3.2.2 processes that result in measures and strategies to achieve the objectives Met? SG Issue Justification/Rationale (Y/N) 60 a Y There are some decision-making processes in place that result in measures and strategies to achieve the fishery-specific objectives. See 80 a)

b Y Decision-making processes respond to serious issues identified in relevant research, monitoring, evaluation and consultation, in a transparent, timely and adaptive manner and take some account of the wider implications of decisions. See 80 b)

80 a Y There are established decision-making processes that result in measures and strategies to achieve the fishery-specific objectives. Achievement of objectives is operationally provided in the Fishing Plan. The NOV meet 4 or 5 times per year; meetings include for annual review of the Fishing Plan. In tandem, the fishery is subject to an Appropriate Assessment which evaluates its effects on the Natura 2000 sites. Any significant adverse effects of the fishery would be accommodated within licence conditions and so the Fishing Plan.

b Y Decision-making processes respond to serious and other important issues identified in relevant research, monitoring, evaluation and consultation, in a transparent, timely and adaptive manner and take account of the wider implications of decisions. Issues identified in an Appropriate Assessment, or identified by fishers or other agencies would be responded to by NOV. The AA and Fishing Plan are publicly available.

c Y Decision-making processes use the precautionary approach and are based on best available information. Management of the Natura 2000 sites necessarily involves precaution, and the production and review of the Appropriate Assessment involves use of the best available information

d Y Explanations are provided for any actions or lack of action associated with findings and relevant recommendations emerging from research, monitoring, evaluation and review activity. Explanations are made available for the licence conditions, Natura 2000 management and Fishing Plan development.

100 b N Decision-making processes respond to all issues identified in relevant research, monitoring, evaluation and consultation, in a transparent, timely and adaptive manner and take account of the wider implications of decisions. No evidence was provided that all potentially significant issues were addressed.

d N Formal reporting to all interested stakeholders describes how the management system responded to findings and relevant recommendations emerging from research, monitoring, evaluation and review activity.

Dutch Oyster Association Oyster Fishery Report page 83 V3

The fishery-specific management system includes effective decision-making PI 3.2.2 processes that result in measures and strategies to achieve the objectives Met? SG Issue Justification/Rationale (Y/N) No evidence was provided of formal reporting processes in Fishing Plan development and review.

References Reglement Visplan 2012, Stakeholder Meetings OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 84 V3

Evaluation Table: PI 3.2.3 Monitoring, control and surveillance mechanisms ensure the fishery’s PI 3.2.3 management measures are enforced and complied with Met? SG Issue Justification/Rationale (Y/N) 60 a Y Monitoring, control and surveillance mechanisms exist are implemented in the fishery under assessment and there is a reasonable expectation that they are effective. See 100 a)

b Y Sanctions to deal with non-compliance exist and there is some evidence that they are applied. See 100 b)

c Y Fishers are generally thought to comply with the management system for the fishery under assessment, including, when required, providing information of importance to the effective management of the fishery. See 100 c)

80 a Y A monitoring, control and surveillance system has been implemented in the fishery under assessment and has demonstrated an ability to enforce relevant management measures, strategies and/or rules. See 100 a)

b Y Sanctions to deal with non-compliance exist, are consistently applied and thought to provide effective deterrence. See 100 b)

c Y Some evidence exists to demonstrate fishers comply with the management system under assessment, including, when required, providing information of importance to the effective management of the fishery. See 100 c)

d Y There is no evidence of systematic non-compliance. Consultations with AID and NOV indicate no systematic non-compliance

100 a Y A comprehensive monitoring, control and surveillance system has been implemented in the fishery under assessment and has demonstrated a consistent ability to enforce relevant management measures, strategies and/or rules. The localised nature of the fishery has allowed for development of a comprehensive MCS system. Requirements and penalties are clearly established in the Fishing Plan, fishers are well aware of these requirements, and enforcement is provided through self-policing (by NOV) and by AID.

b Y Sanctions to deal with non-compliance exist, are consistently applied and demonstrably provide effective deterrence. Sanctions are clearly set-out in the Fishing Plan; the low levels of non-compliance demonstrate the effectiveness of these.

c Y There is a high degree of confidence that fishers comply with the management system under assessment, including, providing information of importance to the effective management of the fishery.

Dutch Oyster Association Oyster Fishery Report page 85 V3

Monitoring, control and surveillance mechanisms ensure the fishery’s PI 3.2.3 management measures are enforced and complied with Met? SG Issue Justification/Rationale (Y/N) As above, consultations with NOV and AID provide confidence in the effectiveness of the system. Regular NOV meetings provide opportunity for sharing of information.

References Reglement Visplan 2012, Stakeholder Meetings OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 100

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 86 V3

Evaluation Table: PI 3.2.4 The fishery has a research plan that addresses the information needs of PI 3.2.4 management Met? SG Issue Justification/Rationale (Y/N) 60 a Y Research is undertaken, as required, to achieve the objectives consistent with MSC’s Principles 1 and 2. See 80 a)

b Y Research results are available to interested parties. See 80 b)

80 a Y A research plan provides the management system with a strategic approach to research and reliable and timely information sufficient to achieve the objectives consistent with MSC’s Principles 1 and 2. Research requirements for the Natura 2000 sites are identified and these will form part of the Ecological Management Plan for both Oosterschelde and Grevelingen; these will include issues related to the fishery together with wider environmental aspects. General research requirements (associated with, e.g. effects of introduced species and the carrying capacity of Oosterschelde) are identified through the Knowledge Group for Oysters, including the Economics Institute, IMARES and NOV. These are considered to comprise separate but interacting research plans.

b Y Research results are disseminated to all interested parties in a timely fashion.

Results from each research strand are made available to interested parties.

100 a N A comprehensive research plan provides the management system with a coherent and strategic approach to research across P1, P2 and P3, and reliable and timely information sufficient to achieve the objectives consistent with MSC’s Principles 1 and 2. A comprehensive research plan as described is not available at present. None of the SG100 requirements are therefore met.

b N Research plan and results are disseminated to all interested parties in a timely fashion and are widely and publicly available.

References Reglement Visplan 2012, Stakeholder Meetings, EFTAS 2011. OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 80

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 87 V3

Evaluation Table: PI 3.2.5 There is a system of monitoring and evaluating the performance of the fishery- specific management system against its objectives PI 3.2.5 There is effective and timely review of the fishery-specific management system Met? SG Issue Justification/Rationale (Y/N) 60 a Y The fishery has in place mechanisms to evaluate some parts of the management system. See 100 a)

b Y The fishery-specific management system is subject to occasional internal review.

See 100 b)

80 a Y The fishery has in place mechanisms to evaluate key parts of the management system See 100 a)

b Y The fishery-specific management system is subject to regular internal and occasional external review. The Fishing Plan is reviewed annually by NOV. Licence conditions contained within the Fishing Plan are reviewed on a three-yearly basis by the Ministry; the effects of the fishery are reviewed through the Appropriate Assessment mechanism which is subject to external review.

100 a Y The fishery has in place mechanisms to evaluate all parts of the management system. The key elements in the operation of the fishery are documented in the Fishing Plan. This contains elements of licence conditions for plots and, in Oosterschelde, the free ground fishery The Fishing Plan is reviewed annually by NOV. Licence condition contained within the Fishing Plan are reviewed on a three-yearly basis by the Ministry; the effects of the fishery on the Natura 2000 sites are reviewed through the Appropriate Assessment mechanism.

b N The fishery-specific management system is subject to regular internal and external review. Although regular internal and external reviews are conducted (see 80 b) there is no evidence of an integrated systematic review of the fishery performance in either waterbody.

References Keus & Holstein, 2008, Reglement Visplan 2012, Stakeholder Meetings OVERALL PERFORMANCE INDICATOR SCORE All Units of Certification: 90

CONDITION NUMBER (if relevant):

Dutch Oyster Association Oyster Fishery Report page 88 V3

Appendix 1.2 Risk Based Framework (RBF) Outputs

Use of the RBF in a fishery assessment form 1 Applicant fishery Dutch Oyster Association Oyster Fishery 2 Conformity Assessment Body Intertek Moody Marine Date that the proposal to use the RBF 5 January 2012 3 is submitted to the MSC Date stakeholder comment period 13 February 2012 4 closes on the proposal to use the RBF 5 PI that RBF is to be used for 1.1.1 Justification for use While there is a significant amount of information on the ecosystem in question, it is 6 not clear that this is entirely adequate, or in the form necessary, to evaluate stock status in relation to target stocks. Summary of stakeholder comments and 7 CAB responses pertaining to choice to use the RBF PI that RBF is to be used for 2.1.1 (note RBF not used for this PI in final 5 assessment as no retained species were identified) Justification for use While there is a significant amount of information on the ecosystem in question, it is 6 not clear that this is entirely adequate, or in the form necessary, to evaluate stock status in relation to retained species stocks. Summary of stakeholder comments and 7 CAB responses pertaining to choice to use the RBF 5 PI that RBF is to be used for 2.2.1 Justification for use While there is a significant amount of information on the ecosystem in question, it is 6 not clear that this is entirely adequate, or in the form necessary, to evaluate stock status in relation to by-catch species stocks. Summary of stakeholder comments and 7 CAB responses pertaining to choice to use the RBF PI that RBF is to be used for 2.4.1 (note RBF not used for this PI in final 5 assessment) Justification for use While there is a significant amount of information on the ecosystem in question, it is not clear that this is entirely adequate, or in 6 the form necessary, to evaluate the status of habitats in relation to the fishery under assessment. Summary of stakeholder comments and 7 CAB responses pertaining to choice to use the RBF

Dutch Oyster Association Oyster Fishery Report page 89 V3

PI that RBF is to be used for 2.5.1 (note RBF not used for this PI in final 5 assessment) Justification for use While there is a significant amount of information on the ecosystem in question, it is not clear that this is entirely adequate, or in 6 the form necessary, to evaluate the status of ecosystem structure and function in relation to the fishery under assessment. Summary of stakeholder comments and 7 CAB responses pertaining to choice to use the RBF Date MSC notified of final decision to 8 use RBF

Dutch Oyster Association Oyster Fishery Report page 90 V3

Appendix 1.2.1 Scale Intensity Consequence Analysis (SICA)

Principle 1 SICA Scoring Template (Target Species - Oosterschelde). Spatial Temporal Performance Risk-causing Intensity Relevant Consequence scale of scale of MSC Score Indicator activities of activity subcomponents score activity activity

Target species outcome Population size

Oosterschelde Reproductive C. gigas capacity Direct 2 5 3 O. edulis capture Age/size/sex 2 80 structure

Geographic range

Rationale: A stock assessment is not available for either of the species concerned in the Oosterschelde. Accordingly, the RBF was used for both. Both target species were considered equivalent in terms of the RBF assessment, and so were awarded the same score. Consultation with IMARES and Industry suggest fishing takes place on 1-10% of distribution of stock in Oosterschelde; based on survey of extent of stock and observations of effects – hence a Spatial Scale of 2. This includes both the culture plots and the ‘open’ fishery through the ‘Kom’ and the western part of the area. It is noted that fishing is not allowed in intertidal areas outside of the Kom, which will serve to reduce the spatial scale of the fishery. Fishing takes place most days except weekends; hence a Temporal Scale of 5, Intensity was considered to be moderate – mainly based on local detection of activity – in plots and in localised instances in the open fishery. The consequence was expected to be most apparent in the age structure of the population; total population size was not expected to

Dutch Oyster Association Oyster Fishery Report page 91 V3

be affected, and reproductive capacity can be maintained by a few large individuals (fecundity being extremely high). The removal of individuals as they reach marketable size is therefore considered the most relevant effect, but these effects are not considered likely to alter overall population dynamics. A Consequence score of 2 was therefore considered appropriate

Principle 1 SICA Scoring Template (Target Species - Grevelingen). Spatial Temporal Performance Risk-causing Intensity Relevant Consequence scale of scale of MSC Score Indicator activities of activity subcomponents score activity activity

Target species outcome Population size

Lake Grevelingen Reproductive capacity C. gigas 2 5 3 Direct Age/size/sex 2 (C. gigas) 80 O edulis capture structure 1 (O. edulis) 100

Geographic range

Rationale: A stock assessment is not available for either of the species concerned in Lake Grevelingen. Accordingly, the RBF was used for both. Fishing within Lake Grevelingen only takes place on managed plots - plots occupy 550 ha versus a total area of 10 800 ha, i.e. 5% of the total area, hence a Spatial Scale of 2. Fishing takes place most days except weekends – hence a Temporal Scale of 5 Intensity was considered to be moderate – mainly based on local detection of activity – in plots; hence an Intensity of 3. The consequence was expected to be most apparent in the age structure of the population; total population size was not expected to be affected, and reproductive capacity can be maintained by a few large individuals (fecundity being extremely high).

Dutch Oyster Association Oyster Fishery Report page 92 V3

The removal of individuals as they reach marketable size is therefore considered the most relevant effect, but these effects are not considered likely to alter overall population dynamics. The management of plots in Lake Grevelingen to promote O edulis is considered a key factor in maintaining the population in this area, and so while C gigas scores 80, O edulis scores 100 reflecting the positive contribution of the fishery to the age/size structure of the population.

Dutch Oyster Association Oyster Fishery Report page 93 V3

Risk-causing Spatial Temporal Intensity Performance activities from Relevant Consequence scale of scale of of MSC Score Indicator fishery under subcomponents score activity activity activities assessment PRINCIPLE TWO: Population size 1 100 Bycatch Species Outcome Reproductive Fishing capacity Species: 2 5 3

Asterias rubens Age/size/sex structure Carcinus maenas

Geographic range

Rationale: Although some experimental studies have been carried out on the effects of fishing on benthic organisms associated with oyster grounds, there is not sufficient information to determine the effects of the fishery. Accordingly, the RBF was used.

The species expected to be most affected by the fishery is either the starfish Asterias or the shore crab Carcinus. The same level of risk was expected for either species. Fishing takes place on 1-10% of distribution of stock in Oosterschelde, and in Lake Grevelingen only takes place on managed plots - plots occupy 550 ha versus a total area of 10 800 ha, i.e. 5% of the total area. The Spatial Scale for both is therefore 2. Fishing takes place most days except weekends (Temporal Scale is 5). Intensity was considered to be moderate – mainly based on local detection of activity – in plots (scale of 3). The consequence was expected to be most apparent in the total population size due to removal and possible damage of organisms during hauling and return to the water, but to be insignificant in relation to the population size of any affected species in either water body.

Dutch Oyster Association Oyster Fishery Report page 94 V3

Dutch Oyster Association Oyster Fishery Report page 95 V3

Appendix 1.2.2 Productivity-Susceptibility Analysis (PSA)

Productivity Scores [1 3] Susceptibility Scores [1 3] PSA scores (automatic)

COMMON_NAME PSA Score MSC Score

Average age at maturity at age Average max age Average Fecundity max size Average sizeMaturity Average at strategy Reproductive (fishbase) Trophiclevel Productivity Total (average) Availability Encounterability Selectivity Post-capturemortality (multiplicative) Total plot PSA on Color C gigas Oosterschelde 1 3 1 1 1 1 1 1.29 1 3 3 3 1.65 2.09 93.4 C gigas Geverlingen 1 3 1 1 1 1 1 1.29 1 3 3 3 1.65 2.09 93.4

O edulis Oosterschelde 1 3 1 1 1 1 1 1.29 1 3 3 3 1.65 2.09 93.4 O edulis Geverlingen 1 3 1 1 1 1 1 1.29 1 3 3 3 1.65 2.09 93.4

Table 1.2.2.a PSA Principle 1 Rationale Table Stock Status – O edulis and C gigas score PI number 1.1.1 same for both Oosterschelde and Grevelingen

Productivity Rationale Score Average age at Maturity at 1-2 years 1 maturity. Average Both species long-lived (>25 years) 3 maximum age Fecundity Oysters are very highly fecund 1 Average Oysters much smaller than 1 meter 1 maximum size Average size at Oysters mature at much less than 40 cm 1 maturity Reproductive Broadcast spawner 1 strategy Trophic level Low trophic level – filter feeder. 1

Fishery Dredge fishery, both Oosterschelde and Grevelingen

Susceptibility Rationale Score Areal Overlap Less than 10% overlap with distribution in either water body – low 1 availability Vertical Overlap Oysters benthic species, targeted by dredge – high encounterability 3 Selectivity Target species 3 Post capture Target species 3 mortality

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Appendix 1.3 Conditions

Table 1.3: Condition 1 Performance PI 2.2.2 Bycatch Management Indicator Score 65

The SG80 requirements for this PI are only partially met. There is not qualitative information and some quantitative information available on the amount of main bycatch Rationale species affected by the fishery, nor does sufficient data continue to be collected to detect

any increase in risk to main bycatch species (e.g., due to changes in the outcome indicator scores or the operation of the fishery or the effectively of the strategy). Information on by-catches in the fishery should be collected so as to allow quantification of the main by-catch species (including plots, but concentrating on free- Condition ground fishery in the Oosterschelde). Factors which may increase the risk to main bycatch species should be identified (e.g., due to changes in the status of bycatch populations or the operation of the fishery or the effectively of the management strategy) and monitored at a suitable frequency. A by-catch sampling strategy should be in place by the first anniversary of certification (Score 65) Quantification of main by-catch species should be carried out by second anniversary of Milestones certification (Score 75).

Factors which may increase the risk to main bycatch species, and a suitable frequency for monitoring these should be identified and monitoring implemented by the third anniversary of certification (Score 80). During the first year of certification an independent scientific research organisation or scientist will be contracted by DOV to estimate discard levels in the oyster fishery with emphasis on the fishery on the free grounds.

Quantitative estimates of by-catch levels in the fishery will be presented to the team at the second surveillance visit. During the third year of certification the estimation of discard levels will be continued.

The results of the first two years of monitoring will be analysed and main by-catch Client action plan species will be identified. Factors that may increase risk to main by-catch species will

be identified and a suitable frequency of an ongoing monitoring of discard levels will be discussed with the independent scientist or organization and implemented by the third surveillance visit.

The results will be presented to the team at the third surveillance visit. After the third year of certification discards will be monitored on an ongoing basis and management measures will be implemented by the third anniversary of certification if considered necessary.

Consultation on Condition to be met by Client. condition

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Appendix 2. Peer Review Reports

Peer Review 1 Overall Opinion

Has the assessment team arrived at an Yes/No Conformity Assessment Body appropriate conclusion based on the evidence Response presented in the assessment report? Justification: The appropriate conclusion has probably been reached, The RBF estimates the risk posed to the although I have some reservations about the sustainability of the targeted population appropriateness of the RBF for oyster fisheries in view of by fishing pressure. In this case, the their potential susceptibility to disease. Recruitment of population is severely restricted by fishable adults in native oyster beds in particular can be Bonamia and in this context, fishing severely disrupted in the long term due to Bonamia does not pose a significant additional infestation and the RBF does not appear to have any risk; indeed management of the means of incorporating this as a factor. Normally one population may help to maintain the would consider that this may not be critical since such population, as noted by the reviewer. fisheries could respond by reducing or suspending fishing effort but this does not seem to be the case with Also, of course, the RBF is a standard this fishery as there is no stock assessment. The fishery MSC process – there may be occasions does respond by trying to keep the stocks at a sufficiently when it is less than perfect, but we seek low density so as to reduce Bonamia infestations (this is a standardised process and predictable widely accepted as the most appropriate response). outcomes of the process, as provided There should be better justification of why the RBF is here. appropriate for this fishery and especially the native oyster fishery.

I have further reservations based on the appropriateness The reviewer is confusing criteria related of assessing C. gigas within the MSC scheme. The report to ‘enhanced fisheries’ with those for includes the following criterion on page 6: ‘introduced species’. Habitat modifications associated with “C1. Habitat modifications are reversible and do not enhancement activities (such as cause serious harm to ecosystem structure and function” provision of artificial habitats) should be reversible. In this case, the nature of the Given the information presented in the report I can fully introduced gigas has caused habitat accept that the habitat modifications (banks of oysters modification, but his is a) not part of the where presumably there would otherwise be soft scope criteria for introduced species and sediments) do not cause serious harm to ecosystem b) a natural process independent of the structure and function. I could also accept they may not fishery. be fundamentally different to banks of mussels or native oyster. However, I am less convinced that they are We are therefore confident that use of realistically reversible. Presumably they would only be the RBF is appropriate and that the truly reversible if C gigas could be permanently fishery is within scope for MSC eradicated from the lakes, which is almost certainly assessment. unrealistic, as the report itself acknowledges. Since the criterion seem to be that they must be reversible AND not causing serious harm I am not convinced that the criterion is met and that MSC assessment is appropriate.

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Do you think the condition(s) raised are Yes Conformity Assessment Body appropriately written to achieve the SG80 Response outcome within the specified timeframe? Justification: Yes the requirements of the condition are clear and appropriate, and it should be perfectly possible for the fishery to implement this and achieve a score of SG80 within the specified timeframe.

If included: Do you think the client action plan is sufficient Yes Conformity Assessment Body to close the conditions raised? Response Justification: Yes the action plan appears to be comprehensive and fit to close out the condition if carried out in full.

General Comments on the Assessment Report (optional)

The report is well written and mostly thorough and comprehensive. However, it would benefit from a few possible improvements.

In particular – the “fishing plan” is alluded to frequently but there is in fact little information on what it contains, how detailed it is, or how it is arrived at, other than that Permit and other restrictions are developed into a fishing plan” and that it appears to be annual. How definitive is it?– I am aware of fishing plans for mussels or oysters in other countries, for example, that specify very clearly how much each vessel can catch on a daily or weekly basis, and often from which specific locations.

It is unclear whether native oyster is fished within the open areas (Oosterschelde only? – where it is known to be at very low density) as well as within cultivation plots.

It is also unclear how extensive or limited the open fishing areas are. If they do not extend over the whole area that is not allocated to plots then they should ideally be shown on the maps or at least better described.

The maps could be better explained as the legends are difficult to understand.

There are two long sections in 3.5.1 in Dutch that should be translated.

Additional minor comments:

IMARES is first mentioned on page 14 but no mention of who they are until page 32.

PVis – mentioned on page 30 and in the scoring table but there is no indication anywhere of who/what this is.

IMM Comment: the above issues have been addressed in the main text.

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Performance Indicator Review Please complete the table below for each Performance Indicator which are listed in the Conformity Assessment Body’s Public Certification Draft Report.

Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to specific scoring issues and any relevant information and/or rationale raised improve documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

1.1.1 See RBF section

1.1.2 Yes Yes This appears to be a default score as a result of using the RBF

1.1.3 n/a

1.2.1 Yes Yes No comment

1.2.2 Yes Yes NA It would not seem unreasonable for C gigas Nonetheless, the fishery must be scored fisheries to score higher here if eradication is against the scoring guideposts provided. not undesirable Score unchanged

1.2.3 Yes Yes NA A possible exception is the native oyster O edulis are very scarce in the fishery on free grounds where there is Oosterschelde and no fishery exists for minimal information on stocks – this should these. Individuals may occasionally be taken be clarified and marketed (hence their inclusion as a unit of certification), but this is insignificant.

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

1.2.4 Yes Yes NA This appears to be a default score as a result of using the RBF

2.1.1 See RBF section

2.1.2 Yes Yes NA I agree that the existing rules and the intense plot management that results in no retained species justify the 80 criteria

2.1.3 Yes Yes NA

2.2.1 See RBF section

2.2.2 Yes Yes NA Clearly if there is no bycatch there is no need for a strategy

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

2.2.3 yes Yes Yes It is clear that more detailed and properly documented information on bycatch than is presently available is required. The score of 65 is reasonable.

2.3.1 Yes Probably but with NA In other enclosed lagoons the possibility that In the Oosterschelde, Zostera grows in the reservations bivalve fishing can increase turbidity levels intertidal area. During low tide, the plant can and could thus affect Zostera beds is absorb sunlight directly and increased accepted, and for this reason a no fishing turbidity levels will affect the seagrass to a buffer zone may in some cases be required lesser extent. around the seagrass beds. Has this possibility been taken into account and if not can the score of 100 be justified? One assumes that if this were a potentially serious issue it would have been identified in appropriate assessments but this should be clarified. The issue may be more potentially serious for the sometimes much heavier dredges that are used for mussel dredging rather than relatively light oyster dredges?

2.3.2 Yes Probably but with NA See above comment re Zostera and turbidity reservations

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

2.3.3 Yes Probably but with NA See above comment re Zostera and turbidity. See above reservations Might information on effects of turbidity, and likely effects of dredging on turbidity, be required?

2.4.1 Yes Yes NA It would be useful to know for which habitat types information was not presented. Nevertheless, the score of 80 is probably justified

2.4.2 Yes Probably but NA See earlier comment about Zostera and See comments above. Possibly not turbidity

2.4.3 Yes Yes NA Whilst I have reservations about the possible effects of turbidity on Zostera, the fact that Zostera has been found to be increasing supports the conclusion and score in this PI

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

2.5.1 Yes Yes NA Whilst I have reservations about the posible effects of turbidity on Zostera, the fact that Zostera has been found to be increasing supports the conclusion and score in this PI

2.5.2 Yes Yes NA The score of 80 is justified

2.5.3 Yes Yes NA The score of 80 is justified

3.1.1 Yes Yes NA

3.1.2 Yes Yes NA I have no strong feeling although arguably a Two out of three SG100 SGs have been met score of 90 might be appropriate in the – this could be interpreted as a 90 or 95, but absence of evidence of active facilitation of most closely fits to a 95, hence this score is consultation awarded.

3.1.3 Yes Yes NA

3.1.4 Yes Yes NA

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

3.2.1 Yes Yes NA

3.2.2 Yes Yes NA

3.2.3 Yes Yes NA

3.2.4 Yes Yes NA

3.2.5 Yes Yes NA

For reports using the Risk-Based Framework: Performance Does the report Are the RBF risk Justification: Conformity Assessment Body Response: Indicator clearly explain scores well- Please support your answers by referring to specific how the process referenced? scoring issues and any relevant documentation where used to Yes/No possible. Please attach additional pages if necessary. determine risk using the RBF Document: Peer Reviewer Template Page 106 of 122 Date of issue: 19 January, 2011 File: TAB_D_031_peer_reviewer_template_v1.doc © Marine Stewardship Council, 2011

led to the stated outcome? Yes/No Yes with Yes with I have reservations regarding the RBF in that it does See comments at beginning of this review 1.1.1 reservations reservations not appear to take into account the possibly severe and long term effect on stocks of disease such as bonamias is in native oyster. This should be clarified. Yes Yes I agree with the conclusions based on lack of retained 2.1.1 species except that I fail to see why the score cannot in that case be higher than 80 mostley Yes Yes There seems to be an assumption that the main Any potentially affected species were considered by 2.2.1 predator species Asterias rubens and Carcinus the experts present at the SICA meeting. Asterias and maenas will be the species most affected. Given that Carcinus were considered the species most likely to there was an RBF workshop at which IMARES were be affected. present one assumes that this was well thought through but it would be useful to see a justification of why other species, for example species using the oyster shells as a substrate upon which to attach and grow, were not assessed. Does not appear to have been assessed by RBF? Correct 2.4.1

Does not appear to have been assessed by RBF? Correct 2.5.1

For reports assessing enhanced fisheries: Does the report clearly evaluate any additional impacts that might arise Yes Conformity Assessment Body Response: from enhancement activities?

Justification: The report evaluates the stabilizing effect of the oyster banks, and specifically considers the enhancement of native oyster stocks as a result of carefully timed placement of cultch. It also

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notes that there is less frequent dredging of native oyster compared to C. gigas as the former is less tolerant of repeated dredging.

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Has the assessment team arrived at an Yes Conformity Assessment Body appropriate conclusion based on the evidence Response presented in the assessment report? Justification:

Do you think the condition(s) raised are Yes Conformity Assessment Body appropriately written to achieve the SG80 Response outcome within the specified timeframe? Justification:

If included: Do you think the client action plan is sufficient Yes Conformity Assessment Body to close the conditions raised? Response Justification:

General Comments on the Assessment Report (optional)

Overall I found this a well written report, and I agree with the conclusions made, as well as the vast majority of scoring. The assessment is complicated by the mixture of native and introduced species, the presence of a significant number of other introduced species, and the altered, and changing, environments that the fisheries are found in. It would help if the report could refer to each species consistently- i.e. ‘native’ and ‘Pacific’ oyster, and not interchange with ‘flat-shell’ and ‘introduced’.

The introduction would benefit from some clearer maps to put the geographical area of the fisheries into context: the only maps in the report are of a small scale, and the geographical location of the fisheries, and relative size, are never made clear. Similarly, the proportion of oyster beds that are both fished, and cultivated, relative to the total distribution of both species, is not clearly articulated. Whilst the 1500 ha + 550 ha of oyster plots are mentioned, this is not placed into context with mention of areas that remain unfished, or ‘free grounds’. Some mention of this is alluded to when scoring the fishery, but even here is not made explicit. I am also struggling to understand the relative size of beds, when the stock assessment summarised on p15 refers to intertidal plots that are clearly much smaller than the overall areas fished.

Whilst the number of licenses and harvest control rules are referred to, there is only an implicit suggestion that there are any restrictions on the size or type of dredge that may be used to harvest oysters.

I agree that RBF and SICA are the correct approach for assessing these fisheries, and agree with the overall scores given for each fishery.

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Typos: P6 3.2 ‘Flat oyster’ not mentioned before, may help to keep terminology the same, use Latin names from the start? P 7 4th para, brackets missing P25 para 4, should read ‘Natura 2000’ P54 PI 2.1.2 is duplicated P87 100 a should read ‘Natura 2000’.

IMM Response: The above suggestions have been addressed in the report.

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Performance Indicator Review Please complete the table below for each Performance Indicator which are listed in the Conformity Assessment Body’s Public Certification Draft Report.

1.1.1 Yes Yes n/a

1.1.2 Yes Yes n/a

1.1.3 Yes Yes n/a

1.2.1 No Yes n/a Details on licence numbers and restrictions Text has been added to Section 3.5.2 of the would help- 31 licences are mentioned in the report text, but no info on how restrictions apply, or any mention of gear regulations

1.2.2 Yes Yes n/a

1.2.3 Yes Yes n/a

1.2.4 RBF is used n/a

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

2.1.1 Yes Yes n/a

2.1.2 Yes Yes n/a

2.1.3 Yes Yes n/a

2.2.1 RBF has been used

2.2.2 Yes Yes n/a There is no stratgey for managing bycatch, other than returning to the sea, RBF allows a score of 80

2.2.3 Yes Yes Yes It should be quite easy to provide The assessment team considered the quantification of main bycatch species by the condition to be appropriate in allowing end of year one, not year 2. Similarly, sufficient time for monitoring strategies to be suitable frequency for monitoring should be developed and implemented. identified and implemented by end of year 1 or 2, not year 3.

2.3.1 Yes Yes n/a

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

2.3.2 Yes No n/a 80 may be a more suitable score? Possibly As there is a comprehensive strategy in more explanation of the comprehensive place, addressing all legal requirements, the strategy wold allow a score of 85, but I don’t 100 a) requirements are met (80 a) asks only see where this goes above international for a ‘strategy’). requirements for protection of ETP species

2.3.3 Yes Yes n/a

2.4.1 No Yes n/a The ‘low impact’ of oyster dredges referred to Information on dredge has been added to here does not appear to be discussed in the main body of report. main report- details on the dredge, and impact, would be helpful

2.4.2 Yes Yes n/a It would be helpful if VMS reports were These do not lend themselves to easy included in the main body of the report incorporation into the report.

2.4.3 Yes Yes n/a

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

2.5.1 No No n/a As the text mentions, the score could well be While the assessment team concur that higher here, there is evidence that the ecosystem disruption is extremely unlikely, fishery is likely to disrupt ecosystem we cannot say that there is evidence to this structure, even if provision of direct evidence effect – hence a score of only 80. would be expensive. Score could be changed to 100.

2.5.2 Yes Yes n/a

2.5.3 Yes Yes n/a

3.1.1 Yes Yes n/a It would help to have some reference to Inspections of VMS data were observed by examples given, such as inspection of VMS the assessment team as part of internal NOV data and court references dispute resolution. The text describes the management/legal system, but does not seek to review all (or recent) cases.

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

3.1.2 No No n/a I can’t find evidence provided for a score of 100b asks for consultation processes, the 100b- where is input from enviornmental assessment team provide evidence that NGOs for example? A score of 90 or 85 processes are in place; how these processes seems more appropriate are used by various organisations is not a scoring issue here.

3.1.3 Yes Yes n/a

3.1.4 No Yes n/a The report would benefit from information Coists of renting plots is not considered relating to the costs of renting plots on which material to the scoring here. Rents may or oysters are cultivated. Do the rents cover may not cover monitoring etc costs, but this costs of stock assessment, monitoring etc, or is seen as a means to help in achieving the is this a hidden subsidy? How are fishermen outcomes expreseed in Principles 1 and 2, strongly encouraged to develop better and not as a perverse inventive. cultivation methods? No evidence for this is provided.

3.2.1 Yes Yes n/a

3.2.2 Yes Yes n/a

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Performance Has all the Does the Will the Justification Conformity Assessment Body Response Indicator relevant information condition(s) Please support your answers by referring to information and/or rationale raised improve specific scoring issues and any relevant documentation where possible. Please available been used to score this the fishery’s attach additional pages if necessary. used to score Indicator support performance to this Indicator? the given score? the SG80 level? (Yes/No) (Yes/No) (Yes/No/NA)

3.2.3 No No n/a No information is supplied about ‘low levels The compliance was confirmed by NOV and of non-compliance’ or details of sanctions AID personnel. It should also be available- required to give the score of 100 remembered that most fishinhg takes place on plots and so self-policing by fishermen is very effective.

3.2.4 Yes Yes n/a

3.2.5 Yes Yes n/a

Any Other Comments

Comments Conformity Assessment Body Response

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2.1.1 Yes Yes

2.2.1 Yes Yes

2.4.1 Yes Yes

2.5.1 Yes Yes

For reports assessing enhanced fisheries: Does the report clearly evaluate any additional impacts that might arise Yes/No Conformity Assessment Body Response: from enhancement activities?

Justification:

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Appendix 3. Stakeholder submissions

Stakeholders were met according to invitations made by the client. No additional stakeholders submitted representations, written or verbal. All information received during the stakeholder meetings is represented and in the report and SICA scoring tables.

(REQUIRED FOR FR AND PCR)

The report shall include all written submissions made by stakeholders about the public comment draft report in full, together with the explicit responses of the team to points raised in comments on the public comment draft report that identify: a. Specifically what (if any) changes to scoring, rationales, or conditions have been made. b. A substantiated justification for not making changes where stakeholders suggest changes but the team makes no change. (Reference: CR 27.15.4)

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Appendix 4. Surveillance Frequency

(REQUIRED FOR THE PCR ONLY)

The report shall include a completed fishery surveillance plan table using the results from assessments described in CR 27.22.1

Table A4: Fishery Surveillance Plan Score from Surveillance Year 1 Year 2 Year 3 Year 4 CR Table C3 Category [e.g. On-site [e.g. On-site [e.g. On-site [e.g. On-site surveillance [e.g. 2 or [e.g Normal surveillance surveillance surveillance audit & more] Surveillance] audit] audit] audit] recertification site visit]

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Appendix 5. Client Agreement (REQUIRED FOR PCR)

The report shall include confirmation from the CAB that the Client has accepted the PCR. This may be a statement from the CAB, or a signature or statement from the client. (Reference: CR: 27.19.2)

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Appendix 5.1 Objections Process (REQUIRED FOR THE PCR IN ASSESSMENTS WHERE AN OBJECTION WAS RAISED AND ACCEPTED BY AN INDEPENDENT ADJUDICATOR)

The report shall include all written decisions arising from an objection. (Reference: CR 27.19.1)

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