In April, when the spring sun starts to prevail, you may spot grass snakes on the north side of Slåensø. They mate from April onwards and may be observed throughout the summer. This is also the time when the deciduous trees start turning green.
In several areas of the forest floor, anemones bloom, but they are less numerous now than earlier as the many deer forage on their roots in the winter. In the light and open meadows, you may see a variety of different flowers, such as broad-leaved marsh orchids, yellow marsh marigolds and ragged robins.
The bird song also peaks now, and with more than 50 breeding species, there is much to see and hear. Start before the trees come into leaf. Listen to the birds that overwintered and note how migrating species slowly appear and join the choir.
In early May, in Millingbæk, Hulebæk and Rødebæk, you may spot lots of roaches which have migrated up from Borre to lay their eggs. Incidentally, Millingbæk acquired its name from the small cyprinids - bleaks - which are locally known as “millinger”. Just like the roaches, the bleaks also migrate to lay eggs in May.