Disquieting data regarding bottom trawling in the Netherlands: A report from Stellendam and Den Helder documents the decline of the industry and the severe ecological degradation.
Our team recently conducted field observations in the Netherlands, where the status of bottom trawling presents a highly contradictory picture. We have previously reported on the critical conditions in Den Helder, north of Amsterdam, and on the island of Texel.
A similar scenario is now evident in Stellendam, the fishing port south of Rotterdam: the inner harbour contains numerous rusting bottom-trawl vessels. According to local fishers, these are destined for decommissioning or resale to other countries (both within and outside the European Union). The Dutch bottom-trawling sector is clearly in decline. This contraction is partially self-inflicted: Brexit, with its associated restrictions on EU waters, and high energy costs are major contributing factors. However, depleted fish stocks resulting from decades of intensive overfishing constitute the primary driver of falling yields.
Conversely, around the outer harbour of Stellendam, "business as usual" continues for the remainder of the fleet. The remaining vessels continue to use dolly ropes extensively and operate between marine protected areas and seal haul-out sites – with ecologically destructive consequences.
Abandoned, lost or otherwise discarded fishing gear drifts through the oceans. Over many years, these nets degrade into microplastics, posing one of the greatest threats to marine ecosystems. Prior to degradation, they present an active, daily hazard to marine fauna, which have not adapted through natural evolution to cope with plastic pollution. Last year, the average number of entanglements for grey seals (Halichoerus grypus) and common seals (Phoca vitulina) in the Netherlands stood at approximately 40 registered, trapped individuals. This data is provided by the three seal rescue centres Pieterburen, Ecomare and Aseal, which coordinate rescue operations. In 2010, 8 incidents were reported; by 2020, this figure rose to 35 – a fourfold increase.
In the first five months of 2024, more than 50 cases have already been documented, exceeding the total for the entire previous year. A linear extrapolation suggests the number of affected animals could significantly exceed 100 in 2024...
Species-specific behaviour influences these figures: grey seals spend more time on sandbanks and are highly inquisitive and playful. They frequently investigate objects, including colourful nets or marine litter washed into the sea. However, beach tourism accounts for only 12% of these incidents; the vast majority (88%) of entanglements are caused by commercial fishing nets, lines and hooks. The specialist Seal Response Team, established by the Pieterburen, Ecomare and Aseal centres, intervenes to capture, untangle and, where necessary, provide veterinary treatment to the affected animals.
The fundamental issue remains bottom trawling. In addition to the severe physical damage these nets inflict on the seabed, the resulting bycatch, and plastic pollution (primarily from dolly ropes), the practice directly impacts North Sea seal populations. Bottom trawling occurs in close proximity to the Dutch coast, with fishers operating immediately adjacent to nominally protected seal haul-out sites. The vessels are close enough to be visible, audible and olfactory-detectable from the shoreline.
Other nations have made greater progress in marine conservation; Greece, for instance, recently announced a ban on bottom trawling in all its marine national parks by 2026. This measure will be extended to all marine protected areas in the country by 2030. Greece is thus the first nation to implement the European Commission's proposal to ban bottom trawling in all protected areas by 2030. While this is a step in the right direction, it does not represent a general ban on this unsustainable, ecologically damaging and carbon-intensive fishing method; it merely excludes it from protected zones. This compromise has halted broader discussions on the topic, allowing industry lobbyists to delay comprehensive regulation.
The weak protection status of marine protected areas currently permits bottom trawling within their boundaries. Only designated "no-take" zones provide genuine protection from commercial fishing and human exploitation. Such zones are virtually non-existent in the EU, with none established in German North Sea or Baltic Sea waters. In 2023, the German Agricultural Minister Özdemir, following protests from North German shrimp fishers, declined to support a ban on bottom trawling in German marine protected areas. This contrasts with the position of the Environment Ministry, given that, on paper, 47% of German marine waters are designated as protected. Consequently, while policymakers endorse the "30/30" target (protecting 30% of the oceans by 2030), they capitulate at the first sign of opposition from industry interest groups. Effective governance requires representatives to prioritise the broader public interest over well-organised lobbying factions.
From a marine conservation perspective, the current situation is highly contradictory. Fishers consistently cite "tradition" to justify their practices. This is not a sustainable argument; historical practices have frequently been superseded by superior, modern standards. It is necessary to phase out traditions that cause ecological degradation and drive climate change.
ElasmOcean advocates for a comprehensive ban on bottom trawling and deep-sea bottom trawling.
