Calidris sandpipers

 

 

 

 

 

 

 

 

 

 

 

 

 

Today, there are 24 species of smallish to very small waders in the genus Calidris. Previously, it contained fewer species, but several birds, which were previously placed in other genera, have been moved to this genus, including spoon-billed sandpiper (C. pygmaea) and ruff (C. pugnax).

The major part of these birds breed in Arctic areas, a few also in sub-Arctic and northern temperate regions. They spend the winter on shores and in inland wetlands in temperate, subtropical, and tropical regions around the world.

The generic name is derived from Ancient Greek kalidris, a term used by Greek philosopher Aristotle (384-322 B.C.) for some grey-coloured water bird. The English term for the smallest members of the genus is stint, of unknown origin. It may stem from the call of the little stint (Calidris minuta), a sharp stit.

I would like to thank Danish artist Jens Gregersen for permission to quote text and use pictures from his splendid book Arktisk sommer (‘Arctic Summer’), first published in 2014.

 

A number of studies in later years have revealed that the females of some species often lay two clutches after arriving at the breeding site, one for the male and one for herself, or sometimes for two different males! When you consider that each clutch weighs almost as much as the bird itself, it is indeed a powerful performance.

The sharp-tailed sandpiper (C. acuminata) breeds in central and eastern Siberia, spending the winter in Australia and New Zealand. In his book Arktisk sommer, Jens Gregersen says: “Lately, scientists have discovered that immature birds perform a strange, irrational migration, going to the Yukon Delta in Alaska, i.e. due east. When you consider that the sharp-tailed sandpiper breeds in the region between the Lena and Kolyma Rivers, it adds up to between 2,000 and 4,000 km in the wrong direction. When they arrive here they are indeed scrawny. They now spend some time here, and the abundant food soon brings them into shape again. Some time in autumn, they continue to Australia, without stopping on the way! This adds up to about 10,000 km, but the sharp-tailed sandpiper has long and strong wings. Their parents took the direct route south through Mongolia and China via Japan, Korea, the Philippines, and New Guinea to Australia, making many stops on the way. Some time in the winter they are united with their young, which made the long detour via Alaska.”

 

 

 

 

 

It spends the winter along shores in temperate, subtropical, and tropical areas, as far south as southern South America, South Africa, and Australia.

The specific name is Latin, meaning ‘white’, referring to its white winter plumage. The popular name is derived from Old English sand-yrðling (‘sand-ploughman’), referring to its feeding habit, running along sandy shores while constantly sinking its bill into the sand in search of food.

 

 

 

 

 

 

 

 

 

 

 

 

 

The specific name refers to mountains of Lapland, from where Swedish naturalist Carl Linnaeus (1707-1778), when he described the bird in 1758, had obtained a specimen. The common name stems from Old English dunling, first recorded around 1530. It is derived from dun (‘dull brown’), with the suffix -ling, meaning a person or another being.

 

 

 

 

 

 

 

 

 

 

 

The specific name commemorates Spencer Fullerton Baird (1823-1887), who worked as naturalist and assistant secretary in the Smithsonian Institution.

 

 

 

 

 

According to legend, Cnut the Great, or Canute, as he was called in England, regarded a certain species of wader, suitably fattened with white bread and milk, as a delicacy. This bird was since known as knot, named after the king. Obviously, Swedish naturalist Carl Linnaeus (1707-1778) knew this legend, because when he described the bird in 1758, he named it Tringa canutus. Today, it is called red knot to distinguish it from the great knot (C. tenuirostris, see below).

Divided into 6 subspecies, the red knot breeds in the far northern tundra in Alaska, north-eastern Canada, Greenland, and central and eastern Siberia. In autumn, it migrates to western Europe, Africa, Florida, Central America, southern South America, Australia, and New Zealand. A few spend the winter in the Mediterranean and in southern India.

When the birds arrive on their breeding grounds in the tundra, very little food is available, so they literally starve. They must depend on fattening up before arriving. On its north-bound migration, birds of the subspecies rufa, which breed on the Arctic Canadian islands, make a stopover in Delaware Bay, New Jersey, to feed on the nutritious eggs of the Atlantic horseshoe crab (Limulus polyphemus), thousands of which gather here in May to lay eggs. This coincides with the arrival of up to one million waders, primarily red knots, turnstones (Arenaria interpres), semi-palmated sandpipers (Calidris pusilla), and sanderlings (Calidris alba).

It has been estimated that each spring birds and fish consume about 320 tonnes of horseshoe crab eggs on American shores. More about this fascinating animal is presented on the page Animals – Reptiles, amphibians, and invertebrates: Horseshoe crabs – living fossils in peril.

 

 

 

 

 

 

 

 

 

During surveys of waders and other water birds along the coast of Tanzania in 1988 and 1989, we counted about 21,000 curlew sandpipers, corresponding to about 86 birds per km. Our ‘guesstimate’ was that around 100,000 individuals of this species winter along the Tanzanian coast. (Source: Petersen, I.K., T. Bregnballe, K. Halberg & O. Thorup 1989. Tanzania Wader Survey. A preliminary report of the Danish-Tanzanian ICBP-expedition 1988. Copenhagen University)

The specific name is derived from the Latin ferrugo (‘iron rust’), from ferrum (‘iron’), given in allusion to its rusty-red breast in the breeding plumage. The common name refers to its down-curved bill, slightly reminiscent of the bill of the curlew (Numenius arquata).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

It spends the winter months along shores of north-western and western Europe, southwards to Portugal, in extreme southern Greenland, and along the North American Atlantic Coast, southwards to South Carolina.

The specific name is Latin, meaning ‘living at the sea’, derived from mare (‘sea’). In winter, the bird is usually observed along coasts.

 

 

 

 

 

 

 

 

 

In autumn, it migrates to the Pacific and Atlantic shores, from extreme south-western Canada and New Jersey southwards through the Caribbean, Mexico, and Central America to northern and western South America.

The specific name was given in honour of Italian botanist Ernesto Mauri (1791-1836), director of the botanical garden in Rome.

 

 

 

 

 

 

 

It winters mainly in Africa, with some numbers around the Mediterranean, and from the Middle East along the coasts of the Arabian Peninsula to the Indian Subcontinent.

In Latin, the specific name means ‘very small’.

 

 

 

 

 

 

 

It spends the winter from southern United States southwards through Mexico and the Caribbean to Peru and northern Brazil.

The specific name is derived from the Latin minutus (‘very small’), and the suffix illa, which denotes something small, thus the name may be translated as ‘very small indeed’.

 

 

 

 

 

 

 

When the breeding season begins, the males gather on an arena on a grassy spot, a so-called lek. When a female arrives at the arena, the males start fighting (in deep silence) to attract the attention of the female. She walks around to survey the entire group before choosing a male, which will mate with her. She then leaves to take care of nest-building, incubating, and chick-rearing by herself.

As a breeding bird, this species is widely distributed in Arctic, sub-Arctic, and northern temperate areas, from eastern England across northern Europe and Siberia, eastwards to around the Kolyma River. There are also scattered populations in Central Asia.

European populations have declined drastically in later years due to draining and overgrowth of suitable habitats.

The wintering area includes southern and western Europe, Africa, the Arabian Peninsula, southern Asia, and to some degree Australia.

Formerly, this species was named Philomachus pugnax, but genetic research has shown that it is closely related to Calidris sandpipers. The former generic name is derived from the Greek philos (‘loving’) and makhomai (‘to fight’), whereas the specific name is derived from the Latin pugno (‘I fight’) and ax (‘inclined to’).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In the breeding season, it is restricted to Arctic and sub-Arctic tundra along coasts of north-eastern Siberia, from Chukotka southwards to the northern part of Kamchatka. It has declined alarmingly in later years, mainly due to destruction of many of its feeding areas in China, on which it is dependent on its way to the wintering areas in southern China, Indochina, and to some degree eastern India. These feeding areas have been converted into salt pans, shrimp farms, and rice fields.

Today, the world population numbers maybe fewer than 100 breeding pairs, and it is feared that it will become extinct in the wild within a few decades. A captive population exists in Slimbridge Wetland Wildlife Reserve, Gloucestershire, England.

 

 

 

 

 

It spends the winter in a vast area, from north-eastern India and Bangladesh eastwards to southern China, and thence southwards through Indochina, Malaysia, Indonesia, the Philippines, and New Guinea to Australia and New Zealand.

The specific name is derived from the Latin rufus (‘reddish’) and collum (‘neck’), alluding to the breeding plumage. In winter, the underside is almost pure white.

 

 

 

 

 

 

 

 

 

In his book Arktisk sommer, Jens Gregersen says: “When I arrived at Tobseda near the delta of the Pechora River in June 2003, I was well received by Dutch zoologist Rudolf Drent (1937-2008). “Look at the small helicopter!” he exclaimed. What he referred to was a Temminck’s stint, which stood motionless in the air, sounding like some distinct grasshopper.”

What he referred to was the remarkable courtship display of the male Temminck’s stint, in which he partly stays motionless in the air with swirling wings, partly runs after the female with lifted wings.

The specific and common names commemorate Dutch zoologist Coenraad Jacob Temminck (1778-1858), who was the first director of the National Museum of Natural History in Leiden, from 1820 until his death. He described this stint in 1815.

 

 

 

 

 

 

 

The population of this bird has decreased alarmingly, mainly due to destruction of many of its feeding areas in China, on which it is dependent on its way to the wintering areas in Malaysia, Indonesia, the Philippines, New Guinea, and Australia. These feeding areas have been converted into salt pans, shrimp farms, and rice fields. Today, the bird is listed as endangered by IUCN.

The specific name is derived from the Latin tenuis (‘slender’) and rostrum (‘bill’).