Actitis hypoleucos

Actitis hypoleucos

The common sandpiper (Actitis hypoleucos Linnaeus, 1758) is a bird belonging to the Scolopacidae family.

Systematics –
From a systematic point of view it belongs to:
Eukaryota domain,
Kingdom Animalia,
Phylum Chordata,
Subphylum Vertebrata,
Aves class,
Order Charadriiformes,
family Scolopacidae,
Genus Actitis,
Species A. hypoleucos.
The term is basionym:
– Tringa hypoleucos Linnaeus, 1758.
The terms are synonyms:
– Actites hypoleucos (Linnaeus, 1758);
– Totanus hypoleucos (Linnaeus, 1758);
– Tringa hypoleucos subsp. hypoleucos Cramp & Simmons, 1977-1994.

Geographic Distribution and Habitat –
The Actitis hypoleucos is a small palearctic wader with a distribution of populations in all continents.
This bird breeds in most of temperate and subtropical Europe and Asia, and migrates in winter to Africa, southern Asia and Australia.
The eastern edge of its migration route passes through Palau in Micronesia, where hundreds of birds may gather for a stopover. They leave the Palau region for their breeding habitats around the last week of April to the first week of May.
In Europe, Finland is the country where it is most present, followed by Poland and Germany. The ringing sites are located both in coastal areas, such as in the Gulf of Finland or Gdansk, and purely continental ones.
In Italy it is also a step species from mid-April to August, but is also present as a winter visitor; it nests wherever there are watercourses, except in Sicily. It is present above all in the central and southern regions and in the major islands the coastal locations prevail.
In the North and in the Po Valley, however, it is also present in inland areas. A strong concentration of reports refers to the coastal complex and wetlands of the Upper Adriatic.
Its habitat in the places of migration is that of inland and coastal freshwater wetlands (seashores), whilst during the winter it appears more linked to salt marshes, lagoons, river mouths, fish farms even in anthropised areas.

Description –
Actitis hypoleucos is a small wader which, as an adult, measures 18–20 cm in length and with a wingspan of 32–35 cm.
Adults are recognized by having greyish-brown upperparts, white underparts, short, dark-yellow legs and feet, and a bill with a light base and dark tip.
In winter plumage, they are duller and have more noticeable barring on the wings, although this is still only visible at close range.
If observed in flight, the wings are curved downwards with a white bar, whilst the rectrices are only marginally white.
Juveniles are very similar to adults but are more heavily barred above and have buff edges on the wing feathers.
This species is very similar to Actitis macularia in non-breeding plumage. But the darker legs and feet and the sharper wing pattern (visible in flight) distinguish it and, moreover, they are only rarely found in the same position.
The chant emits a characteristic “iii-di-di” trill, composed of three detached syllables (the first of which is higher and slightly more prolonged than the others); it is felt mainly at the time of take-off and during the flight.
Furthermore, in the period of April and May, in the nesting areas, it is possible to hear the song of this species, which sounds like a flute “pipitiui – dii, pipitiui – dii”.

Biology –
The Actitis hypoleucos reproduces on banks of rivers close to the water using also old nests of other birds, or in rabbit holes or cornfields distant from the water.
In the Mediterranean it nests in late spring.
The nest is made or identified in a simple cavity in the ground hidden and covered with grasses and leaves.
During the brooding it defends the eggs and the nestlings from the predators by simulating being wounded and, by attracting them towards itself, it takes them away from the nest. When threatened, the juveniles may cling to the parents’ body to be carried away to safety.

Ecological role –
Actitis hypoleucos was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae with the binomial name Tringa hypoleucos.
The genus name Actitis comes from the ancient Greek aktites meaning “coast dweller” from akte meaning “coast”. The specific epithet hypoleucos combines the Ancient Greek hupo meaning “under” with leukos meaning “white”.
This species, depending on the areas, is known by various common names. In the Nukumanu language of the Nukumanu Islands (Papua New Guinea), it is usually called tiritavoi. There is another Nukumanu name for this, matakakoni, but this is considered somewhat taboo and is not used when there are children and women. The reason for this is that matakakoni means “bird that walks a bit, then mates”.
The species is monotypic and, therefore, no subspecies are recognised.
It is a gregarious species and can be seen in large flocks, with the characteristic flight with rigid wings, low over the water, of the wading birds of the genus Actitis.
It usually wags its tail up and down repeatedly when it walks.
The diet of this bird consists mainly of small animals: insects, molluscs, crustaceans, annelids, tadpoles and myriapods.
It feeds by sight on the ground or in shallow water, collecting small foods but can even catch insects in flight.
Actitis hypoleucos is a widespread and common bird, and therefore classified as a species of least concern on the IUCN Red List, but is a vulnerable species in some countries such as Australia. It is also one of the species covered by the Agreement on the Conservation of Migratory Waterbirds from Africa to Eurasia (AEWA).
In Italy, currently, the population does not seem to reach the conditions to be classified within one of the threat categories (population decline of 30% in three generations, reduced number of mature individuals and restricted range). However, it is still threatened by the destruction of its nesting habitat (embankments and sediment extraction from river beds) and being close to the limit for being classified as Vulnerable according to criterion D1, it is probable that it will fall into this category of threat in the near future . It is therefore classified as Near Threatened (NT).

Guido Bissanti

Sources
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– C.Battisti, D. Taffon, F. Giucca, 2008. Atlas of nesting birds, Gangemi Editore, Rome.
– L. Svensson, K.Mullarney, D. Zetterstrom, 1999. Guide to Birds of Europe, North Africa and the Near East, Harper Collins Publisher, UK.

Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/250763956/original.jpeg