As a result of urbanization there is less and less green nature. Animals get a smaller habitat to live and collect food. But the stony man-made towns become a ecosystem in itself. Some animals are able to change their way of living. For example the heron.
In Amsterdam the birds live together with the inhabitants of the city. The herons live in colonies in the top of the trees. In Amsterdam now they live together in the city park. Originally herons are migratory birds, in the winter they leave to warmer habitats. But in the city there is enough food to survive the winter. Besides the fish from the ditches, now the herons have also the goldfish from the neighbor on the menu.
Some herons are even too lazy to find their own food and try to collect it from the local snack bar. Their only problem left are the Sundays and public holidays to which they are not adjusted yet.