Arctic Terns are famed for their incredible migration. Arctic Terns breeding along the frigid shorelines of Greenland or Iceland migrate around 71,000 km per year. The temptation to multiply this with the average lifespan is too great to resist: 30 years x yearly average = 2.4 million kilometres. Three times to the Moon and back, as the tern flies. Birds from The Netherlands fly even further: down the coast of Europe and Africa, then just past Cape Town, and east to Australia or even New Zealand, then south to the Antarctic. One bird holds the record of the longest known migration for any animal: 91,000 km in a year. This species sees more daylight than any other creature, and has pretty much perpetual summer – making its scientific name of
S. paradisaea quite fitting. Sick or exhausted Arctic Terns rarely join tern roosts along the coast, but for the most part they are pelagic, and migrate well offshore. They are most commonly encountered in spring and autumn on passage. But expect the unexpected: in September 1996, Dave Allan and Andrew Jenkins found an Arctic Tern flying above Katse Dam in Lesotho, not only 500 km from the sea, but also way up in the mountains!
Germany, September
Longest migratory flight of about 90,000km per year
The Antarctic Tern is a regular winter visitor to South Africa. The first birds arrive about April in the Western Cape and May in the Eastern Cape and numbers build up to a peak in August. Departure takes place mainly in September and October, and is complete by November, with only isolated birds remaining in South Africa for the summer months.
It feeds at sea, and is often seen as far as 150 km offshore. The distribution at sea extends from about Hondeklipbaai in the Northern Cape to about Cape Padrone at the eastern limit of Algoa Bay in the Eastern Cape. It roosts gregariously, with other species of gulls and terns. Regular roosts lie in a narrower range than the "at sea" records, and are between Lamberts Bay and Cape Agulhas and between Cape St Francis and Bird Island, Algoa Bay. Beyond this area it is a vagrant, with records from as far as Walvis Bay in Namibia and from KwaZulu-Natal. Most roosts are on the offshore islands; on the mainland it uses headlands with flat rocks and sheltered sandy beaches. Large mainland roosts have been recorded at Grootpaternosterpunt (32 44S, 17 54E), Bekbaai (32 49S, 17 53E), Mauritzbaai (32 59S, 17 53E), North Head, Saldanha Bay (33 03S, 17 55E), Kommetjie (34 08S, 18 19E), Danger Point (34 38S, 19 17E) and Cape Recife (34 02S 25 43E).