Final answer:
Moose visit roadside ditches in spring to consume salt and minerals washed away from the roads, a behavior which is part of their seasonal changes.
Step-by-step explanation:
Moose in spring visit roadside ditches to lick salt and other minerals essential for their nutrition after a long winter. During the spring, when the snow melts, minerals and salt that were spread on roads for de-icing purposes are often washed into adjacent ditches. The moose, along with other wildlife, are attracted to these areas as a source of necessary minerals, which can be scarce elsewhere in their environment. This behavior is part of their natural seasonal changes, similar to other wildlife migration patterns where animals travel in search of resources necessary for survival.