This June 2015 video is about a boat trip in Dutch Naardermeer nature reserve.
Ever since 1906, the Naardermeer lake is the oldest nature reserve in the Netherlands. In 1874, before it was a nature reserve, a railroad track was built, separating the northern and southern parts of the lake.
Now, the railway is reconstructed. That opportunity is used to add six wildlife tunnels to enable animals to cross safely under the railroad. These tunnels are supposed to be ready at the end of 2019, radio show Vroege Vogels reported today.
This 2013 animation video is about a wildlife corridor built then, from the Ankeveense plassen to the Naardermeer nature reserves, enabling, eg, otters to cross. That corridor indeed made it possible for otters to reach the Naardermeer.