I just learned what a waterlot is. It's "A legally defined area of land covered by water which may be either contiguous or attached to dry land, or may be separated entirely from dry land; may be filled, partially filled, or not filled; or a piece of land normally covered with water at high tide."
For example the whole of Deep Cove is a waterlot administered (not owned) by the District of North Vancouver. The DNV can make bylaws covering the waterlot. The bylaw listed above says no fishing or crabbing in waterlots and therefore there is no fishing or crabbing allowed in Deep Cove by boat or from shore.
The ocean at Cates Park is not listed in the bylaw as a waterlot and therefore the DNV has no control over anything beyond the high tide line.