There are missions on all three oceans and the Great Lakes, in fact. In the north they are conducted when the major shipping seasons are there, and in particular they provide tailored support for coast guard operations—for example, when ships are transiting ice-infested waters in the Northwest Passage. They also operate on the east coast. On the surveillance programs, for example on oil pollution, they would be designed to target where the most vulnerable areas are and overlap with areas that are going to see the largest amount of shipping and potential risk.
