An article posted on LRT.lt by environmental scientist Rimantė Balsiūnaitė, currently working with the Arctic Economic Council, and journalist Augustinas Šulija asks an important question: Will the Baltic Sea survive? Their conclusion is that ecological consequences are taking their toll on one of the youngest seas in the world, due to decades-long mismanagement of fisheries, pollution, and accelerating global warming. Here is a summary of their findings.
The spirals and vortexes of phytoplankton spreading for dozens and even hundreds of kilometres look fascinating from space but are causing growing concern for environmentalists, scientists, and local fishermen. These dead zones are expanding, mainly due to extensive algae bloom, a process that deprives large parts of the sea of oxygen. And the cod population that stands at the centre of the food chain of the Baltic Sea is collapsing.
In the port city of Klaipėda, both boat-owners earning a living from recreational cod fishing, and the biggest commercial fishing companies in the country fear for their livelihood. Eastern Baltic cod stock was once the largest in the Baltic Sea, with healthy fish of various sizes. Only 20 years ago, fish hauls in Baltic ports were nearly 70,000 tonnes a year, with still over 50,000 tonnes in 2010. By 2018, they had decreased more than threefold.
Due to years of overfishing, cod spawns younger and grows smaller, according to Conrad Stralka from the Swedish BalticSea2020 Foundation, which seeks to raise awareness about the plight of the Baltic Sea. He confirmed that this might have a long-term impact on cod fishing prospects. Due to high mortality, the spawning stock biomass is lower than what is required for the fish to reproduce. The International Council for the Exploration of the Sea (ICES) has also noted that the cod population is highly infested by parasites, distributed by the growing population of grey seals.
Following dire scientific assessments, the European Union decided to take an unprecedented decision. In an attempt to save the collapsing fish stock, a ban was introduced on fishing cod in the eastern part of the sea, while the fishing quotas for western area cod stock, as well as other fish stocks, were heavily restricted.
EU estimates show that only a minority of companies fishing Eastern Baltic cod, representing up to 50% of the national fleets in Lithuania, Latvia, and Poland, are resilient enough to survive even temporary fishing limitations. According to the Baltic Marine Environment Protection Commission, established by the EU and countries around the Baltic Sea also known as the Helsinki Commission (HELCOM), additional measures are needed for the cod populations to recover.
Currently, more than 97% of the Baltic sea suffers from eutrophication, an excess of nutrients as a result of which the Baltic seabed is the largest “dead zone” in the world. Stralka explained that without large predatory fish, the stocks of Baltic herring and sprat will increase. These then bring about a risk of reduction in the amount of zooplankton, which in turn can lead to an increase in the amount of phytoplankton, meaning that the effects of eutrophication will only increase.
The tourism sector of the Baltic Sea is also facing growing challenges. Even though most algae blooms are not harmful to people, some cause a high concentration of cyanobacteria Nodularia spumigena and could cause dangerous reactions in the body, from simple rash and reddening on the skin to diarrhea and vomiting, if swallowed. In recent years, algae washed up on shore caused beach closures in Poland, and in Sweden, coastal pollution by algae resulted in millions in lost revenues for hotels and major expenditures in shore cleaning.
The EU has also concluded that nutrient loads to most parts of the Baltic sea, which is the main reason for algae growth, are still in excess of regionally agreed goals. Over the years, excessive amounts of nutrients from sources such as agriculture, industries and municipal wastewater are extremely slow to be digested by the ecosystem. Climate change has been shown to exacerbate algal blooms that thrive in warmer water and weather.
The EU has yet to come up with practical solutions on how to address these ecological issues. But in September 2020, the ministers of environment, agriculture and fisheries from eight EU countries surrounding the Baltic Sea signed a new enviromental declaration. The document declares the EU’s commitment to reduce pollution in the Baltic Sea, secure sustainable fisheries and improve the general biodiversity in the Baltic Sea.
