Date of this Version
At eight urban or industrial sites in southern Ontario colonies of Ring-billed Gulls (Larus delawarensis) were controlled to ameliorate problems caused by the adults and their young. At the Nanticoke Generating Station on Lake Erie a growing colony was eliminated by collecting eggs and subsequent harassment of adults. One colony at the Stelco Yards in Hamilton Harbor was eliminated by installing a gull exclosure and collecting eggs from nests outside the exclosure and another was controlled by frequently destroying nests and eggs. At Toronto Island Airport an incipient colony was controlled by collecting eggs and harassing adults. At Mugg's Island, Toronto Harbor, control efforts included construction of a large gull exclosure and repeated egg collection. Large-scale gull-scaring operations during 1984-86 at the Eastern Headland, Toronto Harbor, included the use of tethered raptors, distress cries and pyrotechnical devices. A new colony at Bluffer's Park, just east of Toronto on Lake Ontario, was eliminated by collecting eggs repeatedly. A colony on the yards of the St. Mary's Cement Company in Bowmanville was reduced by alteration of habitat and harassment of the adults.