 In addition to maintaining existing structures and upgrading lighting apparatus, he selected the site, drew up plans and supervised construction of at least 8 lighthouses, 6 of which were completed in his lifetime.His finding of a message in a bottle and publication of the note with the location of its retrieval provided information to those studying the pattern of ocean currents in the Atlantic.Two of the sixteen lighthouses awarded designation under the Heritage Lighthouse Protection Act as historically significant in Newfoundland, Green Island and Cape St. Mary's, were built under the supervision of Oke.