Forster's Tern

Status Rare vagrant and transient. An immature female was collected on 4 September 1924 by L.A. Purcell at Maynard Lake, Dartmouth; a severe southerly gale had lashed the province on 26 August. A second bird was reported by Charles R.K.Allen and Lloyd B.Macpherson from Lawrencetown, Halifax County, on 19 October 1958. A third was seen by Mr. Allen at West Chezzetcook, Halifax County, on 11 September 1960. Between 27 October and 1 November 1968, following the wake of hurricane "Gladys," six birds were seen in the area of Cole Harbour and Cow Bay, Halifax County, and one was seen near Port Felix Harbour, Guysborough County. An immature bird was well documented on 23 May 1970 at Seal Island (B.K. Doane). In 1984, there were several reports: on 15 July and 14-15 September at Conrad Beach, Halifax County; at Eel Lake, Yarmouth County, on 17 November; and at Crescent Beach, Lunenburg County, on 29-30 December (photographed). Other fall or early-winter terns that have been reported may have been this species. These include individuals (some reported as Common Terns) on the Halifax East Christmas Bird Counts of 1981 and 1983, and near Cape Sable on 10 February 1975.

Remarks Adults in breeding plumage resemble the Common Tern but have heavier bills, longer legs and, in flight, the bases of the inner primaries are distinctly silvery white. Winter adults and immatures have a distinctive dark bar behind their eyes.

Forster's Tern breeds on the North American prairies, along the east coast from New York State to North Carolina, and on the Gulf of Mexico. Birds in Nova Scotia may be vagrants from the south (especially after storms) or transients from the centre of the continent, which normally migrate to the east coast further south.