Meaning of "course of the year"

I don't quite get the meaning of course of the year in the following sentence.

They search for food by moving over ice from island to island during the course of the year.

What does course mean here?

Solution 1:

Course here means the passage of time, so "course of the year" means "throughout the year." See Dictionary.com:

the continuous passage or progress through time or a succession of stages: in the course of a year; in the course of the battle.

It means much the same as ‘during the year’, but perhaps empasizes the year’s movement from month to month and from season to season.