The Baltic Sea is in crisis. Several fish populations have collapsed and others are in steep decline. The most recent scientific advice on fishing opportunities paints a sobering picture of the state of forage fish populations like Baltic herring and sprat in the Baltic Sea. Current fishing limits, although some have been reduced in recent years, will not ensure the recovery of these essential species. Urgent measures are necessary to prevent further degradation of both fish populations and the marine ecosystem. Against this background, it is imperative that EU fisheries ministers take a more precautionary approach, including ecosystem considerations, when setting fishing opportunities for 2025.
Key issues that fisheries ministers must take into account when setting fishing opportunities next week:
- Single-species advice is preventing an ecosystem-based approach to fisheries management: Single-species advice is preventing an ecosystem-based approach to fisheries management. The current system for setting fishing opportunities is based on single-species advice, largely ignoring the need to consider the value of weaker sub-populations at risk, poor size and age distribution, interspecies dynamics (such as between sprat/herring and predator-prey relationships) and the impact of mixed fisheries on vulnerable stocks, for example, cod bycatch in flatfish fisheries or herring in sprat fisheries. We are concerned that both scientific advice and the decision-making process continue to focus on maximising the exploitation of single species, rather than taking these broader concerns into account and building resilience for the future.
- Declining forage fish populations: Baltic herring and sprat, two critical forage fish species, are experiencing significant declines. The Spawning Stock Biomass (SSB) of central Baltic herring is below the precautionary Btrigger level, while sprat recruitment has fallen sharply for several consecutive years (2021–2023) and is now among the lowest seen in the time series. In addition to these alarming trends, scientific assessments for the central Baltic herring and the Gulf of Bothnia herring stocks indicate poor stock conditions, including unhealthy age and size distribution, and a vulnerability to loss in genetic diversity due to the existence of several distinct subpopulations.
- Ecosystem vulnerability: Forage fish are keystone species to the Baltic Sea’s food web. As prey for species which used to be commercially important, like cod and salmon, as well as seabirds and marine mammals, their depletion may have cascading ecological effects. Allowing these relatively short-lived species to recover through application of more precautionary fishing limits, combined with other appropriate remedial measures, is crucial not just for biodiversity, but also for the recovery of other species.
- Uncertainties in stock assessments and catch misreporting: Inconsistent data and misreporting between species, such as sprat and herring, introduce uncertainties into stock assessments. ICES highlights (1), that species misreporting is an ongoing problem, yet these effects have been neither quantified nor included in the assessment because a lack of access to representative data. Overestimations of stock size have previously led to inflated quotas, exacerbating the decline of key species. To mitigate these risks, EU fisheries minister must adopt fishing limits that include a buffer for uncertainties. This would prevent overfishing based on potentially overestimated stock data.
FishSec recommendations for fishing limits for 2025
The European Commission’s proposal for 2025 fishing limits in the Baltic Sea is a step in the right direction but does not go far enough to ensure rebuilding of the important forage fish species. Given the current significant uncertainties in the stock assessments, declining fish populations, misreporting and poor environmental conditions, agreed fishing limits must incorporate precautionary buffers.
Western herring:
All targeted fishing for the western Baltic herring stock has been closed for some years now but despite the ICES zero catch advice (2), fisheries ministers have been setting bycatch quotas. Bycatch quotas, even small quantities, can threaten the fragile recovery of depleted stocks. While we would ideally see a full closure, including for bycatch, FishSec welcomes the Commission’s proposal to reduce the bycatch quota. Additionally, further remedial measures are needed to secure rebuilding of this stock, including:
- Develop a stock rebuilding plan to ensure rapid recovery above BMSY.
- Implement additional measures to protect and restore known spawning habitats and nursery areas, as indicated in the ICES advice.
- Implement additional area and/or time restrictions on the herring fishery in the eastern parts of the North Sea divisions 4a, 4b and in division 3a, as catches of Western Baltic Spring Spawning herring in the fishery for North Sea herring will be inevitable (3).
Central herring:
The scientific advice on central Baltic herring highlights a concerning situation. The stock is far from the target level for resilience, with only a slim chance of recovery by 2026. ICES now estimates that the biomass has been near or below the limit reference point for spawning stock biomass (Blim) since the mid-1990s, remaining below this critical level for several years. In 2024, the biomass is expected to rise slightly above Blim, but the spawning stock remains below the precautionary Btrigger level. Recruitment for 2023 and 2024 is uncertain, adding to the stock’s vulnerability. ICES also warns that genetic diversity and productivity are at risk due to the stock’s complexity, such as the existence of sub-populations. Finally, the well-known catch misreporting might result in an overestimation of stock size, leading to overfishing if the TAC is set too high.
FishSec recommends setting the TAC well below FMSY lower and implement further remedial measures, such as:
- Develop a rebuilding plan to ensure rapid stock recovery to levels above BMSY.
- Improve control, enforcement, onboard monitoring and sampling of landings to ensure that the misreporting of sprat and herring is minimized.
- Trial spatial and temporal closures to enhance stock recovery, as recommended by the ICES roadmap for possible conservation measures for central Baltic and Gulf of Bothnia herring (4).
Gulf of Riga herring
Whilst the spawning-stock size is above MSY Btrigger, Bpa and Blim, the recruitment estimates for 2023 – the final assessment year – is considered uncertain. FishSec recommends setting the TAC ≤ 32,796 tons in order to build ecosystem resilience by allowing the stock biomass to increase more substantially.
Gulf of Bothnia herring
This stock shows significant vulnerabilities. The spawning-stock size is below Btrigger and scientific assessments indicate overall low productivity, an unhealthy age & size distribution, low spawning stock biomass levels and a vulnerability to loss of genetic diversity due to the existence of several distinct subpopulations. Whilst the scientific assessment shows a small increase in SSB between 2023 and 2024, FishSec recommends that the TAC is set at a precautionary level, due to the poor stock conditions; a TAC below the FMSY lower value.
Sprat:
Sprat recruitment has been very poor for four years in a row and as a result the biomass has substantially decreased but is still just above the Btrigger level. The stock forecast is based on optimistic recruitment estimates, meaning the biomass could fall below Btrigger if recruitment is lower than expected. Additionally, none of the catch scenarios within the FMSY range ensures that the probability of the stock falling below Blim is less than 5%, as is required under Article 4.6 of the Baltic MAP. The well-documented misreporting adds further uncertainty that must be taken into account. Considering all these worrying aspects, FishSec recommends setting the TAC for sprat well below the FMSY lower level.
In addition, FishSec recommends the follow remedial actions:
- Develop a rebuilding plan to ensure rapid recovery above BMSY.
- Put in place spatial management and measures to account for species interactions (e.g. by spatial or temporal limitations).
- Increase control, enforcement, onboard monitoring and sampling of landings to ensure that the widespread misreporting of sprat as herring and of sprat as non-quota species such as flounder and stickleback does not continue.
(1): ICES (2024). Herring (Clupea harengus) in subdivisions 25–29 and 32, excluding the Gulf of Riga (central Baltic Sea), page 3. https://doi.org/10.17895/ices.advice.25019276.v1
(2): ICES (2024). Herring (Clupea harengus) in subdivisions 20–24, spring spawners (Skagerrak, Kattegat, and western Baltic). ICES Advice: Recurrent Advice. Report. https://doi.org/10.17895/ices.advice.25019273.v1
(3): ICES. 2024. Herring (Clupea harengus) in subdivisions 20-24, spring spawners (Skagerrak, Kattegat, and western Baltic). In Report of the ICES Advisory Committee, 2024. ICES Advice 2024, her.27.20-24. https://doi.org/10.17895/ices.advice.25019273
(4): ICES (2024). EU request to establish a roadmap for possible conservation measures for central Baltic and Gulf of Bothnia herring. ICES Special Request Advice: https://doi.org/10.17895/ices.advice.25435741.v1