Scientists urge visitors to skip swimming in bog pools to protect biodiversity
Estonian researchers say frequent swimming disrupts the ecosystems of bog pools and recommend visitors use other bodies of water instead.
Estonia is home to many pristine bogs, and visitors often use their pools for swimming, but experts say this habit is taking a toll on the fragile environment. Nature tourism guide Imre Arro explains that heavy swimming activity has thoroughly mixed the water in the main swimming pools, erasing the natural temperature difference between the surface and deeper layers. Vegetation surveys along the edges of popular swimming pools also revealed an overgrowth of grasses at the expense of dwarf shrubs, which have receded.
Another concern is sunscreen and other cosmetic products washing into the water. Marika Kose, senior lecturer in nature tourism at the Estonian University of Life Sciences, said residue from these products settles in the water and forms a visible layer, though its exact ecological impact still needs further study.
Impact scales with foot traffic
According to Kose, the degree of change depends on how often and in what manner people visit a given bog area. Research shows that even a small number of visitors can cause minor local disturbances, but in heavily visited wetlands such as Viru Bog, Kakerdaja Bog and Kõnnu Wetland, where many people walk both on and off marked trails, the accumulation of such small changes may be harming the wetlands overall.
Scientists stress they are not calling for a ban on touching bog water, but suggest visitors reconsider whether swimming there is truly necessary. Kose recommends a brief dip to experience the water before leaving without adding further pressure on the site. She noted that larger lakes equipped with swimming infrastructure, as well as other lakes, rivers and beaches designated for swimming, are better suited for the activity.
