Photo: Pixabay

 

When EU fisheries ministers negotiated this year's fishing quotas in the Baltic Sea last autumn, Sweden and Finland signed their own bilateral agreement to introduce a temporary trawling ban in the Bothnian Sea (subdivision 30). 

The trawl ban will apply to industrial pelagic fisheries within the territorial limit (12 nautical miles from the coastline) during the period 25 May to 30 June. Exceptions are made for fishing for human consumption. 

The aim is to protect herring that aggregate for spawning or migrate to coastal spawning areas, thus ‘strengthening herring spawning and contributing to stronger year classes’.

Why ban fishing when there is no fishing?

The Swedish proposal was sent out for consultation in April. In its response to the consultation, Stockholm University's Baltic Sea Centre states that the proposal ‘appears to be ineffective’ and needs to be supplemented with other measures to achieve its aims.

"Moving the trawl limit is a positive step. But it is implemented in far too short a time. And why place the fishing ban during a period when there is no fishing anyway?" says Charles Berkow, policy officer at the Baltic Sea Centre. 

Charles Berkow. Foto: Lisa Bergqvist

No fishing within 12 nautical miles

Finland and Sweden account for all herring fishing in the Bothnian Sea. Most of the fishing takes place earlier in the year – and outside the 12-mile limit. A study of Baltic herring fisheries in the Bothnian Sea between 2011 and 2022 shows that only five per cent of the catches (both Swedish and Finnish) were taken within the 12-mile limit (Source: Swedish University of Agricultural Sciences, SLU.aqua.2022.5.2-392)

Last year, a total of ten Swedish vessels fished for herring in the Bothnian Sea last year. None of these vessels engaged in trawling within the 12-mile limit during the period 25 May to 30 June, according to an impact assessment of the proposal, made by the Swedish Agency for Marine and Water Management (SwAM).

SwAM concludes that the regulation ‘is not expected to have any consequences for fishing in the area.’

Risky management

According to ICES, the spawning biomass of Baltic herring in the Gulf of Bothnia is below the threshold value for maximum sustainable yield (MSYBtrigger) and close to or possibly below the threshold value for safe biological limits (Blim). 

Article 5(1) of the EU multi-annual management plan therefore requires measures to ensure a rapid rebuilding of the stock. In order to meet these requirements, the Baltic Sea Centre proposes the following in its consultation response:

• extend the trawling ban to the entire Bothnian Sea (sub-area 30), not just within the 12-mile limit
• extend the closure period to apply from 1 January to 30 June
• extend the trawl ban to both Swedish and Finnish fisheries.

‘In recent years, herring fishing has been allowed to be far too extensive, with quotas that are far too high in relation to the status and development of the stock. The price for this risky management is that strong measures are now required for the Baltic herring to have a chance to recover,’ says Henrik Svedäng, associate professor of marine ecology and researcher at the Baltic Sea Centre.

Henrik Svedäng.

Protecting sub-stocks

Baltic herring in the Gulf of Bothnia is managed as one stock. But genetic studies show that herring are actually divided into a number of smaller sub-stocks, which aggregate and spawn at different locations and times of the year. Last year, for example, a group of large herring (slåttersill) was discovered in the southern parts of the Bothnian Sea. It is genetically distinct from other herring and has historically been caught by local coastal fishermen around midsummer. 

‘Vessels in the pelagic industrial fishery can catch several hundred tonnes of herring in a single trawl. Such large catches concentrated to site-specific areas threatens local sub-stocks,’ says Henrik Svedäng. 

Once a sub-stock in a specific sea area has been fished out, it can take many years before herring re-establish themselves in that area – if they do at all. 

Protecting these important sub-stocks is therefore a key part of rebuilding herring stocks, coastal ecology and local small-scale fishing in the Gulf of Bothnia, says Henrik Svedäng.

‘There should be an immediate ban on trawling within the territorial limit, i.e. within 12 nautical miles of the coastline, throughout the year. In addition, the so-called migration areas within the current trawl limit must be completely closed to trawling,’ Svedäng says.

Text: Henrik Hamrén