Along the trail you can hear birds singing almost all the year round. The Eurasian blackbird (Turdus merula) starts in March; typically you can hear its flute-like song in the morning and in the evening from high on the top of a big spruce. Other thrushes, like the redwing (Turdus iliacus) and song thrush (Turdus philomelos) join the concert in April—May with their melodious singing. The master singer nightingale (Luscinia luscinia) arrives when the trees leaf out. The bushes along the trail, where the ground is not thickly covered by growing plants, are its favorite places. Its song comes from relatively low, whereas singing resembling that of a nightingale, but coming from higher on the trees and bushes, might be a garden warbler (Sylvia borin) or a blackcup (Sylvia atricapilla), the bird in the beloved Christmas carol by Z. Topelius, “Sylvia`s Carol.” The robin (Erithacus rubecula) sings in spruce forests, and its song resembles the jingling of silver bells.
In the autumn, when the sun shines at the same angle as in March, the blackbird tunes its singing again as if to say farewell before starting its migration to the south. Some blackbirds even winter in Hartola near feeding places. When the blackbirds finish their song, the white-throated dipper (Cinclus cinclus) continues the concert throughout the winter.