Pluvialis squatarola
Pluvialis squatarola
The grey plover (Pluvialis squatarola, Linnaeus 1758) is a bird belonging to the Charadriidae family.
Systematics –
From a systematic point of view it belongs to:
Eukaryota domain,
Kingdom Animalia,
Phylum Chordata,
Subphylum Vertebrata,
Aves class,
Order Charadriiformes,
Family Charadriidae,
Genus Pluvialis,
P. squatarola species.
The term is basionym:
– Tringa squatarola Linnaeus, 1758.
The terms are synonyms:
– Charadarius squatarola (Linnaeus, 1758);
– Squatarola cinerea (Flem.);
– Squatarola helvetica (Linnaeus);
– Squatarola squatarola (Linnaeus, 1758);
– Tringa spec Linnaeus, 1758;
– Vanellus melanogaster Bechst..
Within this species the following subspecies are recognised:
– Pluvialis squatarola subsp. cynosurae (Thayer & Bangs, 1914);
– Pluvialis squatarola subsp. squatarola;
– Pluvialis squatarola subsp. tomkovichi Engelmoer & Roselaar, 1998.
Geographic Distribution and Habitat –
Pluvialis squatarola is a cosmopolitan bird.
They are migratory birds that migrate to winter in coastal areas around the world. In America, they winter from southwestern British Columbia and Massachusetts south to Argentina and Chile; On the old continent they are found from Ireland and southwestern Norway south through coastal Africa to South Africa, while eastward from southern Japan south along all of coastal southern Asia and Australia, with some reaching as far as New Zealand. Most migratory birds in Australia are females.
This bird makes regular non-stop transcontinental flights over Asia, Europe and North America, but is mostly a rare ground vagrant within continents, landing only occasionally when forced down by bad weather or to feed on coast, shores of very large lakes such as the Great Lakes, where it is a common migrant.
Furthermore, it passes through some inland areas of Africa (Niger, Zambia, etc.) and Asia (Laos), and on some islands of the three oceans (Sant’Elena, Christmas Island, Nauru, etc.).
In Italy it is a regular migratory and wintering species, and during the passage it stops on the banks of ponds and lakes.
Its nidification habitat, of preferences, is in the tundra of the arctic areas of Europe, Asia and northern America, from which it migrates in winter to more temperate areas. It nests in the Arctic islands and the coastal areas along the northern coasts of Alaska, Canada and Russia.
Description –
Pluvialis squatarola is a bird 27–30 cm long, with a wingspan of 71–83 cm and a weight of 190–280 g, (up to 345 g in preparation for migration).
The male in wedding dress has a light white-grey coloration with dense blackish speckles in the upper parts.
The beak, legs, throat, cheeks, chest, neck anteriorly, abdomen and flanks, up to the armpits, are black.
A white area extends from the shoulders, tapering, to behind the ears and as an eyebrow to the forehead.
The female in nuptial dress resembles the male but with the black areas of the chest, neck, throat and cheeks mottled with white.
Males and females are indistinguishable in nature in winter dress which is characterized by the upper parts on a light gray base suffused with light fawn and dense blackish speckles. The underparts are off-white with soft brown mottling on the breast. Paws, beak and underarm area remain black.
In all seasons, males and females have blackish wing tips with an evident white wing bar.
Juveniles closely resemble adults in winter dress.
Biology –
The Pluvialis squatarola prepares the nest with small twigs and lichens in a circular depression in the moss or peat. The breeding habitat is the Arctic islands and coastal areas along the northern coasts of Alaska, Canada and Russia.
During the year it carries out a single brood and the deposition takes place between mid-June and July.
It lays 3-4 eggs which are incubated for about 23-27 days by both the female and the male and both parents provide for the rearing of the offspring.
The chicks fledge when they are 35-45 days old.
Furthermore, young birds do not reproduce until they are two years old; they typically remain in their wintering grounds until their second summer.
Ecological role –
The Pluvialis squatarola is a typically gregarious bird in the winter period. It can often be observed associated in flocks with the sandpiper. It feeds walking on the ground with little water and on the beaches looking for small molluscs, crustaceans, annelids, insects and their larvae, seeds and other vegetable substances.
It is less gregarious than the other Pluvialis species, it does not form dense feeding flocks, but instead feeds widely dispersed on beaches, with birds well spaced apart. Instead, they tend to form dense flocks on perches at high tide.
From the point of view of their ecological status, the International Union for Conservation of Nature (IUCN) has judged the threat to the gray plover “least concern”. It is one of the species to which the Agreement on the Conservation of Afro-Eurasian Migratory Waterbirds (AEWA) applies.
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/252181775/original.jpeg