Swans gather in large numbers at Nissinjärvi in Kuusamo, Finland before migration

In autumn, gatherings of swans before migrating to their wintering areas significantly increase Finland’s population of mute swans. This phenomenon is particularly visible at Nissinjärvi in Kuusamo, where hundreds of resting and feeding swans can be observed.

As winter approaches, mute swans that will spend the colder months in the Baltic Sea straits of Denmark gather in specific shallow lake regions in northern Finland. Such locations are found near Oulu’s Liminganlahti, as well as in Kuusamo. At peak times, as many as 1,000 swans can be counted at Nissinjärvi. Local biologist Jyrki Mäkelä estimates that around 150 to 200 swan pairs breed in Kuusamo, with thousands arriving in the autumn. He speculates that these swans may have migrated from Russia and possibly northern Sweden, some even from Lapland.

Swans can remain on shallow lakes well into late autumn, sometimes for several weeks, as long as the water remains unfrozen and food is available. They tend to leave once the lakes freeze over, according to Mäkelä.

Currently, Finland’s mute swan breeding population is reported to be just over 10,000 pairs, while the autumn population swells to around 70,000 birds. Mäkelä notes that the growth of the swan population in Finland is stabilizing. Although the population grew robustly a decade ago, the rate of increase has slowed down. Historically, the mute swan population, which was once on the brink of extinction due to hunting, has been growing at an average rate of about 10% annually in recent decades. However, this growth has decelerated in many areas due to limited suitable breeding habitats. Despite these challenges, Mäkelä believes swans are thriving in Finland. He also notes that while larger bird species such as cranes and swans are doing well, many smaller duck species have unfortunately declined.