Voting by the south coast district board on the adoption of all items on its agenda shall be by rollcall. Unless any board member objects, a substitute rollcall may be used on any agenda item. A substitute rollcall shall consist of a unanimous voice vote of the south coast district board members in attendance and shall be recorded by the clerk of the board as an “aye” vote for all members present. For purposes of this section, any consent calendar is a single item.