On 9 September 2021 Jim and Therese Carroll were birding at Red Head marsh near Saint John, NB. Flocks of migrating shorebirds were present feeding on the marsh. Shorebirds can be difficult to identify so they were looking carefully trying to find what species were there. Going over flocks of peeps (small shorebirds) with their binoculars, Therese spotted something different, very different. Using a telescope, they soon recognized what they were looking at was not anything any of us expected to see here in New Brunswick, a Curlew Sandpiper (Calidris ferruginea). Fortunately Jim was able to capture some identifying photos which are shown here on this blog. Many thanks to the Carrolls for finding and documenting this rare visitor!
Curlew Sandpipers have only been seen a few times in North America since accurate ornithological records have been kept. There are a few records from the 1800s and in recent times we only have a small number. According to A.C. Bent, Life Histories of North American Shore Birds, 1962, the Curlew Sandpiper was an occasional visitor to North America. With the exception of one record from Point Barrow, AL all other occurrences have been from the eastern coast of North America (New Jersey 1829, Long Beach 1903, Cape May in 1868, Massachusetts in 1865); from Canada twice, from the eastern US about 10 times, from the West Indies twice and from Patagonia once. The Canadian records were from Toronto (1868) and Nova Scotia.
Recent sightings include two by our own Roger Burrows. One in moulting plumage was seen and photographed in Newfoundland on July 15, 1985 at the Robin Hood Bay/ Cadet Road area of St. Johns by Doug Phelan and Roger Burrows. Roger has also reported a juvenile from the Thoroughfare Road, Grand Manan on 9 September, 2009. No photo was obtained from that sighting.
So where should this bird normally be? In short, the species breeds on the eastern Siberian tundra and winters in central and south Africa, Asia and Australasia. It passes through much of Europe and Asia on its migrations, following a different path north and south. Its path north is more west than its path south. It is seen in the British Isles in July to October; Denmark from August to October; on the Baltic shores, all Mediterranean countries, North Africa, Canary Islands, across Asia to the Indian Ocean, Malasia, China, Australia and New Zealand during migration. It is rare in Britain in spring but large flocks are seen around the eastern Mediterranean. In spring migration it moves through some of Europe. For example, it has been recorded from Gibraltar April 24, Egypt May 8, and also in April in Greece, Italy, Cyprus, and also at Lake Baikal and China. That is a wide migration route! In fall it has been recorded from Ireland in August to September, Greece in September, Africa in November. Casual records have been from Madagascar, New Zealand, Bering Island and North America. In other words, it covers most of the Old World with some vagrants seen elsewhere. This bird takes a very long migration route, sometimes up to 15,000 km. That covers the distance from north-eastern Siberia to South Africa. The breeding range of this bird is small (north-eastern Siberia). Of all shorebird species, its breeding range is the smallest in comparison to its non-breeding range. As rare as this species was/is in North America the records tell us that in 1844 there were a dozen specimens for sale at the Fulton market on Long Island.
Although the photos make one think we are discussing a rather large species, the Curlew Sandpiper is a peep, a small shorebird. It is 22 cm long (8.5 inches). Compare this to our very common Semi-palmated Sandpiper which is 16 cm (6.3 inches) long and the Dunlin to which it is closely related which is also 22 cm (8.5 inches) long. The top photo shows the size difference compared to the Semi-palmated Sandpiper.
The Curlew Sandpiper is described as more slender than the Dunlin but with longer wings, neck and legs. The closest species we would have to distinguish it from are the Dunlin and the Stilt Sandpiper. When the Curlew Sandpiper is in breeding plumage there is no problem. The breeding plumage shows the beautiful rufous red colour on the breast, head, neck and sides. The black bill is long and decurved. The legs are black and medium-length. The back is a mottled chestnut colour and the wings are grayish. There is barring on the sides and under the tail. In flight it shows a white rump which is a good feature to distinguish it from the Dunlin. It also has a white wing stripe shown in flight which is used to distinguish it from the Stilt Sandpiper. The female is similar to the male. In non-breeding plumage the red fades and the birds become pale gray on the dorsal aspect and white below with a white supercilium. The in-between plumage is a very interesting mottled gray and red with a mottled gray and brown back. The juvenile shows a yellowish gray on the neck and upper breast on an otherwise gray and brownish plumage with white below. I hope we get a chance some day to try to identify one of these plumages!
It is interesting to look at where this species got its name. The 'Calidris' is from ancient Greek. Kalidris was a term used by Aristotle which was used to mean a gray-coloured bird which stayed near the water. Ferruginis is from Latin meaning iron rust and refers to the beautiful colour of the breeding plumage.
Studying the courtship and breeding of this species has been difficult. They are difficult to see on the Siberian tundra and early records were from people stranded on the tundra or iced in or Arctic boating expeditions. Recent work has provided more data. These birds arrive on the breeding grounds in Eastern Siberia in June. They have been observed in small groups chasing one another around. The male performs an aerial display for the female. Nests are built on the drier part of the tundra on a gentle slope. These areas are dotted with reindeer moss and tufts of wiry grass which are taller than the birds so they can hide easily from predators. They can also get a wide field of view from these locations. Several nesting pairs build nests in the same general area. The nest is a deep hollow in the soil lined with mosses, lichens and leaves. One nest was reported to have 4 eggs present in a deep hollow with the narrow, pointed end of each egg pointing downwards. The eggs are pale yellowish-white with a greenish tinge and spotted with small blackish-brown which become confluent near the large end. Nesting occurs even when there are still patches of snow on the ground. Some researchers report that the small egg size and the bold markings make the eggs easily identified. The eggs are up to 39.6 mm long. They are incubated for 21 days by the female. After nesting both young and adults gather in large flocks and they stay on the tundra until autumn.
Curlew Sandpipers feed on insects, snails, marine worms, crustaceans, small molluscs and some vegetable matter. They forage by probing the mud rapidly while walking. They will wade belly-deep in the water while probing. This species is not very vocal but on the breeding grounds their alarm call is a rapid 'wick, wick, wick'. Their flight call is somewhat like that of the Dunlin but purer in tone and sounds like, 'kril'l'l'lee'.
The population numbers of the Curlew Sandpiper are in trouble like most shorebird species of the world. Counts have been done in South Africa where they are most numerous and the counts show a 40% decline from 1975 to 2009. The effects of global warming on their breeding grounds, pollution and habitat loss are some reasons for this decline. Population numbers also flucuate with the populations of lemmings in the north. If lemming numbers are down, then Skuas and Snowy Owls will prey on nesting shorebirds including the Curlew Sandpiper. The Curlew Sandpiper is protected under the Agreement on the Conservation of African-Eurasian Migratory Waterbirds.
The Curlew Sandpiper occasionally hybridizes with the Sharp-tailed Sandpiper or the Pectoral Sandpiper. The Curlew/Sharp-tailed cross is called the 'Cooper's Sandpiper'. The Curlew/Pectoral cross is called the 'Cox's Sandpiper'.
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