The white-cheeked tern (Sterna repressa) belongs to the family of gulls and terns, the Laridae.
The white-cheeked tern species is distributed in northeast African coast, coastal Red Sea, Persian Gulf, coastal Iran, coastal Pakistan and west coast of India. These tern species are partially migratory. These terns are monotypic species.
Appearance, physical description and identification
The white-cheeked tern (Sterna repressa) is a medium-sized tern, measuring 30 to 35 cm in length and weighing 75 to 140 grams. The wingspan is 75 to 85 cm.In breeding terns, the back, wings, rump and uppertail are colored darker shades of gray. There is a black cap extending over eyes, nape and hinderneck. The forehead is pale gray. The face and cheek region is whitish. The underparts are pale gray.
The bill is red, dark red or blackish. The base of the bill tends to be dark red. The irises are black. The legs are dark red or blackish. The call of these white-cheeked tern species is a mild, repeated "keeur..keeur" or "kyar..kyar" sound.
1.Indian birds - Photo of White-cheeked tern - Sterna repressa by Shah Jahan |
2.Birds of India - Photo of White-cheeked tern - Sterna repressa by Mike Prince |
3.Indian birds - Photo of White-cheeked tern - Sterna repressa by Mike Prince |
4.Birds of India - Photo of White-cheeked tern - Sterna repressa by Mike Prince |
Origin, geographical range and distribution
These white-cheeked tern species are distributed in Kenya, Somalia, Djibouti, Eritrea, Sudan, Egypt, Saudi Arabia, Yemen, Oman, UAE, Qatar, Bahrain, Kuwait, Iraq, Iran, Pakistan and India.In India, these white-cheeked tern species are distributed in the coasts and coastal waters of the states of Gujarat, Maharashtra, Goa, Karnataka, Kerala and Lakshadweep Islands.
The Important Bird and Biodiversity Areas (IBA) of these white-cheeked tern species in UAE are Yasat Island, Sir Bani Yas Islands, Muhaimat Island, Dayyinah Island and Al Ushsh Island. The IBA in Qatar are Al-Aliyah island and Shara'awh island.
The IBA of these white-cheeked tern species in Saudi Arabia are Tarut Bay, Gulf of Salwah, Gulf coral islands, Farasan Islands and Abu Ali. The IBA in Oman are Ra's Abu Da'ud, Masirah island, Daymaniyat Islands and Bandar Jussah.
Ecosystem and habitat
These white-cheeked tern species do not normally occur in forest. They normally occur in altitudes from 0 to 100 meters.The natural ecosystems and habitats of these tern species include coastal freshwater lakes, estuaries, marine lakes, lagoons, sea cliffs, offshore islands, sandy, rocky shorelines, coral reefs, shallow seas with macroalgal growth and open seas.
Diet and feeding behavior
The diet of these white-cheeked tern species consists mainly of fish. Small fish (small-sized (5 cm) silverside, herrings, shads, sardines, ilish and menhadens) and invertebrates are their primary food.The white-cheeked terns usually follow the predatory fish and marine mammals and plunge-dive to catch the schooling fish driven upwards by the larger predators. They also pick the prey off the surface of water. They also forage in shallow waters.
Reproduction and breeding habits
The breeding season of these white-cheeked tern species is from July to September in Egypt, Somalia and Kenya. The laying season is during May and June in Sudan and Oman. They nest in well-dispersed loose colonies (del Hoyo et al. 1996).These white-cheeked tern species are monogamous and territorial. The nesting sites are located on inshore and offshore islands, coral islands, sandy and gravel beaches, sand dunes and sand flats above the high-tide levels.
The nest of these tern species is a scrape on rock, sand, gravel or coral. The clutch contains 2-3 eggs. The incubation and fledging periods are not known. The fledged chicks remain dependant on the parents for several weeks.
Migration and movement patterns
These white-cheeked tern species are partially migratory birds. The populations occurring across eastern Red Sea coast and Persian Gulf are migratory. They migrate eastwards to the coastal regions of Iran, Pakistan and western India for wintering.The white-cheeked tern populations occurring across the northeast coast of Africa, spanning Egypt, Sudan, Eritrea, Djibouti, Somalia and Kenya, are non-migratory resident birds (del Hoyo et al. 1996).
Post breeding, the resident juvenile white-cheeked tern may disperse and establish in new locations within the range. Within their range they may make local movements for feeding and breeding.
White-cheeked tern - Quick Facts
- Scientific name: Sterna repressa
- Species author: Hartert, 1916
- Synonyms/Protonym: Sterna repressa E. J. O. Hartert, 1916
- Family: Laridae › Charadriiformes › Aves › Chordata › Animalia
- Vernacular names: English: White-cheeked tern, Chinese: 白颊燕鸥, French: Sterne à joues blanches, German: Weißwangen-Seeschwalbe, Spanish: Charrán arábigo, Russian: Аравийская крачка, Japanese: アラビアアジサシ
- Other names: Whitecheeked Tern, White-cheeked Tern
- Distribution: northeast African coast, Red Sea coast, Persian Gulf, coast of Iran and Pakistan, west coast of India
- Diet and feeding habits: small fish, invertebrates
- IUCN status listing: Least Concern (LC)
Conservation and survival
The global population size of the white-cheeked tern (Sterna repressa) has not been quantified. The overall population trend of the species is considered to be decreasing.In most of its range, this tern species is reported to be uncommon to rare. The generation length is 11 years. Its distribution size is about 8,880,000 sq.km.
Habitat alteration and destruction, human intrusions and disturbance at the nesting sites and egg-harvesting are the main threats that are endangering the survival of these tern species.
IUCN and CITES status
The white-cheeked tern (Sterna repressa) does not approach the thresholds for being Vulnerable, either under the range size criterion, or under the population trend criterion or under the population size criterion.The IUCN (International Union for Conservation of Nature) has categorized and evaluated the tern species and has listed it as of "Least Concern".
The CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) status is ‘Not Evaluated’ for the white-cheeked tern (Sterna repressa).
1.Photo source: https://en.wikipedia.org/wiki/File:White-cheeked_Tern.jpg (cropped)
Photo author: Shah Jahan | License: CC BY 3.0 as on 5/1/18
2.Photo source: https://www.flickr.com/photos/mikeprince/15271127301/ (cropped)
Photo author: Mike Prince | License: CC BY 2.0 as on 5/1/18
3.Photo source: https://www.flickr.com/photos/mikeprince/15087350659/ (cropped)
Photo author: Mike Prince | License: CC BY 2.0 as on 5/1/18
4.Photo source: https://www.flickr.com/photos/mikeprince/15271086981/ (cropped)
Photo author: Mike Prince | License: CC BY 2.0 as on 5/1/18
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