Cockle fisheries

The Wadden Sea was by far the most important catching basin for cockles. Large quantities of cockles can also be found in the Voordelta, the Oosterschelde and the Westerschelde. There is a lot of demand in southern European countries for this specialty. That made the cockle fisheries a lucrative business with annual turnovers between 45 and 68 million euros. However, the vacuum system caused local disturbance to the tidal flat bottom. And tidal-flat birds also needed cockles to survive.

Since 2005, the mechanical cockle fisheries in the Wadden Sea has been banned. Cockles are now only fished manually in the Wadden Sea. Between 2004 and 2006, the cockle fisheries in the Oosterschelde also came to a halt, but only on a temporary basis. Manual cockle fisheries is still allowed on a limited basis in the wadden region.

There was a long and sometimes fierce discussion about the scientific study which precluded this decision. You will find a summary of EVA2 further up. When the government decides to abolish a certain form of fisheries, reorganizations and disposal of ships prevent the fishermen from continuing this kind of work elsewhere. This did not occur in the case of the mechanical cockle fisheries. However, the fishermen did receive financial compensation. In fact, they received 85 million euros in total.

The cockle fisheries is a risky industry. There is an abundance of cockle in good years while bad years can mean catching practically nothing. For example, after the severe winters of 95-96 and 96-97, there were so few cockles that it was very difficult to keep the fleet in business. The two years following were extremely good cockle years.

Shackles and vacuum trawls

The Dutch have been fishing cockles by hand since the Middle Ages and mechanically from ships since 1950. Mechanical fisheries use the cockle trawl, a cage on a carriage with a knife hanging in between. The sand between the cockles is sprayed away using a hose placed in front of the knife, and then the cockles are sucked on board with a kind of vacuum cleaner.

Mechanical cockle fisheries grew rapidly since the beginning of the 1970s. Even though the number of licenses were frozen in 1974 at 37, the increase in capacity and improved fishing techniques resulted in increasing yields. In 1991, the cockle fleet grew to 40 ships. But it stabalized by 1999, with 37 licenses exploiting 22 ships and employing 400 people in the sector. By 2003, only three boats fished for cockles.

Paella

After being cleaned, the cockles are boiled and then frozen or canned. Cockles are not consumed much in the Netherlands, but are mostly exported to Spain (for the paella) and Portugal. The fishing season begins around early September and lasts for three months. Cockle fishermen must have a special license due to the Nature Protection Act.

Cockle stock

The cockle stock varies tremendously from year to year. In the Wadden Sea, for example, there were 22.5 million kilograms of cockles in 1990, while in 1991 there were only around 5 million kilograms and in 1992 more than 40 million kilograms! A few years later, in 1998, there were more than 145 million kilograms of cockles in the Dutch tidal waters, a result of the soft winter of `97-`98. In that year, the Wadden Sea harvested nine million kilograms and the Westerschelde 0.6 million kilograms. The Oosterschelde was closed for cockle fisheries.

The cause of the large fluctuations in the past years is not fully understood. In any case, severe and very mild winters appear to influence the cockle stock. Many cockles die during severe winters, while all cockles seem to survive mild winters, including the weak ones. However, other harmful organisms for cockles also survive mild winters.

War on the flats

In 2000, tidal flat specialist Theunis Piersma, two hundred other biologists, eight hundred sympathizers and twenty nature organizations had requested that the undersecretary (Faber) not grant any licenses to the cockle fishermen due to the enormous amount of damage that the fisheries brought to the environment. Lengthly studies of the benthic fauna around the island of Griend showed that recovery could take up to eight years after a fishing vessel had fished the area. The enormous number of deaths among the eiders was another effect. The lack of food in 2000 and 2001 resulted in around 20,000 deaths among the eiders each year (20% of the population), all of which was to the (mechanical) cockle fisheries.

Years of fierce controversy followed between the cockle fishermen and their representatives on the one side and the nature conservationists on the other side. The lobby group 'Wilde Kokkels' (wild cockles) placed dead eiders near the UN nature conference in the Hague. Fishermen hit lobbyists in front of the cameras during the fishery days in Lauwersoog. The subject cockle fisheries was constantly mentioned in the newspapers and other media. Nevertheless, the fishermen received their licenses every year from the Ministry, to which the nature organizations would object, often times without results. The TV-program Zembla made a documentary called 'Het complot op de Waddenzee' (the complot on the Wadden Sea). Theunis Piersma received a prize from the Prins Berhhard Foundation in 2004 for his efforts to preserve the nature.

EVA2

In the meantime, undersecretary Faber had an evaluation started in 2000 (EVA2) to study the effects of the cockle fisheries. The results of this scientific research would be determinant for the new shellfish fishery policy for the following ten years. In January 2004, the results of the EVA2 studies were made known by the Ministry of Fisheries (LNV). The most important conclusion was that the cockle fisheries damaged the Wadden Sea tremendously, however that in the future it could be possible to fish for cockles in a durable manner on a limited scale.

Other results from the EVA2 study:
- a declining amount of nutrients in the water could decrease the carrying capacity for shellfish
- the cockle fisheries influence the establishment of eelgrass
- mussel banks have recovery slightly due to fishery policies
- there was more biomass of cockles in closed areas than in areas open for fishing
- the amount of food being reserved for birds has not been enough in the past
- oystercatchers have declined in numbers, probably due to the disappearance of mussel banks
- eider populations have probably declined due to a shortage in food.

In addition, it was advised to set up a good monitoring program to keep a systematic eye on the Wadden Sea.

Advice group Wadden Sea Policy ('Meijer commission')

The Advice group Wadden Sea Policy (commission Meijer) was set up to advise the government about the shellfish fisheries and gas exploitation in relation to nature. The commission proposed to reduce the cockle fisheries within the following seven years and reform it into a durable fishery. They also found gas exploitation acceptable.

End of cockle fisheries

In September 2004, the European Court judged that the government was only allowed to permit activities such as mechanical cockle fisheries when it is certain that there are no damaging effects for the natural habitats and the wild flora and fauna. Based upon this decision, the Council of State denied the request from the cockle fishermen to fish in the Wadden Sea in 2004. In addition, they decided that the licenses given by the Ministry for Food Quality in 1999 and 2000 were given unjustly. the mechanical cockle fisheries in the Wadden Sea were ended per 1 January 2005. The Minister also wanted to end the shellfish fisheries in the North Sea to prevent the cockle fisheries from switching over to spisula and razor clams. The fishermen received 123 million euros as compensation.

An overview of the damage caused by the cockle fisheries appeared at the end of 2006, written up by a number of wetland biologists. According to the scientists, some populations of migrating bird species, such as the knot, have declined. During their heyday, there were more than 120,000 knots on the flats while anno 2006 only 20,000 are found. The cause is not only the lack of cockles but also the change in sediment that took place when the bottom was churned up. The tidal flat bottom has become less muddy and more sandy. The living situation for the shellfish has worsened resulting in less meat. Consequently, there is not only less to eat for the tidal flat birds, the quality has declined.