The Kentish plover (Charadrius alexandrinus ) is a small cosmopolitan shorebird (40-44 g) of the family Charadriidae that breeds on the shores of saline lakes, lagoons, and coasts, populating sand dunes, marshes, semi-arid desert, and tundra. Both male and female birds have pale plumages with a white underside, grey/brown back, dark legs and a dark bill, however additionally the male birds also exhibit very dark incomplete breast bands, and dark markings either side of their head, therefore the Kentish plover is regarded as sexually dimorphic
Charadrius alexandrinus has a large geographical distribution, ranging from latitudes of 10º to 55º, occupying North Africa, both mainland, such as Senegal, and island, such as the Cape Verde archipelago, Central Asia, for example alkaline lakes in China, and Europe, including small populations in Spain and Austria. Some populations are migratory and often winter in Africa, whereas other populations, such as various island populations, do not migrate. Its common English name comes from the county of Kent, where it was once found, but it has not bred in Britain since 1979.
Kentish plovers are ground-nesting birds, often with a preference for low, open, moist nesting sites away from thick vegetation and human activity. They use a number of materials to build their nests, mainly consisting of shells, pebbles, grass and leaves in a small scrape in the ground. Like most plovers, the Kentish plovers are predominantly insectivores, feeding on a large range of arthropods and invertebrates depending on the environment, by using a run and stop method.
The Kentish plover is a small shorebird weighing around 40 g as an adult. Both male and female birds have black bills and dark legs, however adults have dimorphic plumage. During the breeding season, males have a black horizontal head bar, two incomplete dark breast-bands on each side of their breast, black ear coverts and a rufous nape and crown (although there is some variation between breeding populations), whereas the females are paler in these areas, without the dark markings. In the early breeding season, it is easy to distinguish between males and females since the ornaments are very pronounced, but as the breeding season progresses, the differences between the two sexes decrease. Moreover, males have longer tarsi and longer flank feathers than females. Longer flank feathers are thought to be an advantage for incubation and brood care, as the quality of feathers is associated with heat insulation.There are multiple significant predictors of plumage ornamentation in Kentish plovers. Firstly, the interaction between the advancement of the breeding season and rainfall seem to affect ornamentation.
Male ornaments become more elaborated over the course of a breeding season in regions with high rainfall, whereas in regions with low rainfall, male ornaments become lighter. Secondly, the interaction between the breeding system and the sex can predict the degree of plumage ornamentation. In polygamous populations, the sexual ornaments are more pronounced, generating a stronger sexual dimorphism than in monogamous populations. The difference is especially witnessed in males, whereby the ornaments are darker and smaller in polygamous populations compared to monogamous populations, where males have lighter and larger ornaments. This is thought to be the result of a trade-off between the size and intensity of the ornaments.
Kentish plovers have an extremely wide geographical distribution and their habitats vary not just spatially but environmentally too. They are known to reside and breed in multiple types of habitat, from desert with ground temperatures reaching 50 °C to tundra. The distribution of this species’ breeding areas covers Europe, Asia and Africa,). In Europe, populations are typically found in the west; although there was once a breeding population in Hungary, Kentish plovers no longer breed there. In Africa, populations are found on the southern coast of Senegal and along the Northern coast of the Mediterranean, and the Red Sea coast. The breeding area continues along the Arabian Peninsula, Saudi Arabia, Qatar, and Bahrain in the Middle East. Small populations can be found on islands too, such as the Cape Verde archipelago, the Canary Islands, and the Azores. It is a rare vagrant in Australia. Some populations do not migrate, such as the Maio (Cape Verde) population, however other populations can migrate reasonable distances, for example, plovers that spend winter in North Africa have been known to migrate to Turkey and Greece in the spring. Some birds breeding in western Europe are not known to travel very far, just within Europe, however some do travel, mainly to Western Africa.
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