Anyone driving on the waterfront in St. John's can see a vessel called Gulf Pacific, owned by Gulf Fleet, an offshore supply boat company.
Since these pictures were taken and posted to the Gulf Fleet website, someone installed a large radar dome on almost amidships.
The dome is curiously similar in size to the ones used to house missile tracking radars. It likely isn't anything too mysterious as missile tracking radars come in a set of different types.
It's still curious, though.