The most valuable species in Finland?
Is it possible to value different species and say that one species is the most valuable of them all? While biodiversity is most important in both habitats and species diversity, in one way the freshwater pearl mussel is the most valuable species in Finland.
In a 1995 decision by the Ministry of the Environment, individual values were defined for all protected animals and plants in Finland. In 2002, the former Finnish currency marks were updated to euros. The natural value of one freshwater pearl mussel (FPM) has been set at 589 鈧�. For comparison: the most valuable species in terms of individual value is the Saimaa ringed seal (9 755 鈧�), but there are only 480 of them in Finland, so their total value is 4,58 million 鈧�. There can be an enormous number of Norway lemmings (67 鈧�) in peak population years. There would have to be at least 20 million of them for their value to reach the natural value of the FPM.
In Finland, there are currently known to be around 150 FPM streams, most of them in Northern Finland. Dozens of new populations, mainly in small headwater streams, have been searched for and found in the last 15 years. In 2021, Finland adopted a conservation strategy and action plan for the FPM, which is now being implemented also by LIFE Revives. The goal of the FPM strategy is to improve knowledge of the mussel occurrences and their habitats and to make this knowledge available to the public. And since FPM do not reproduce without trout or salmon, the condition of their habitats must also improve. And when restoring FPM streams, the habitats of mussels in the catchment areas must also be taken into account. Migratory fish and FPM are closely linked.
How many FPM are there in a river? This is determined by conducting a population status survey. The survey is carried out in accordance with a CEN standard refined for Nordic countries. FPM are counted in transects, samples are measured, and it is checked whether juveniles are present and, if so, how they have grown. The results provide a population count and a measurement-based assessment of the state of the FPM population, which can range from viable to nearly extinct.
Since last summer, the status of FPM has been assessed in 86 populations, representing over half of all known populations (Figure 1). This progress has been made possible by both the Ministry of the Environment's Helmi habitat program and LIFE Revives. A tremendous amount of new information has been gathered: only 17% of the studied populations have been assessed as viable or possibly viable, while the rest have been classified as non-viable or dying. And so, 65 FPM populations still need to be assessed.
But! Let's get back to the most valuable species. Based on estimates of both studied and less thoroughly investigated FPM populations, Finland is home to approximately 2,2 million FPM. Multiplying this number by 589 鈧� per mussel yields a total value of 1,3 billion 鈧�. If my calculations and comparisons with other protected species and their values hold true, the freshwater pearl mussel can be declared Finland's most valuable species. However, we cannot compete with Sweden or Norway in this 'country match'; our neighboring countries have over a thousand FPM streams and a population of nearly 200 million mussels.
The value of the species also means that if you ride an ATV over an FPM stream and crush 100 mussels, the court may order compensation of 58 900 鈧�.
However, we do have the opportunity to catch up in terms of FPM numbers and improve the viability of populations. This will require the cooperation of thousands of landowners, various authorities, and stakeholders to ensure that trout and salmon can migrate to FPM streams and that water protection is taken seriously with adequate buffer zones. The many benefits of freshwater pearl mussels in river ecosystems are a topic for another discussion.
Author: Pirkko-Liisa Luhta, project manager, Mets盲hallitus Luontopalvelut