St Helena Swamphen
Encyclopedia
The Saint Helena Swamphen (Aphanocrex podarces) was a large flightless rail from Saint Helena
. It became extinct in the early 16th century.
When American ornithologist Alexander Wetmore
described this species from subfossil remains which were found at Prosperous Bay
, Saint Helena, he classified it into the new genus Aphanocrex. However, in 1973 American paleontologist Storrs Olson synonymised this genus with the genus Atlantisia which other representative is the Inaccessible Island Rail
(Atlantisia rogersi). While Olson had considered it as congenor of the Inaccessible Island Rail
, other scientists regarded it not even as close relative and so it was renamed into Aphanocrex. The Saint Helena Swamphen was relatively large and reached almost the size of the New Zealand Weka
(Gallirallus australis). In contrast to the Weka it was more slender. Since Saint Helena was predator free until the sixteenth century, the swamphen had lost its ability to fly but it wings were better developed like the wings of the rails from Inaccessible Island and Ascension Island
. Furthermore it had strong toes with long claws which give that species a good ability to climb and flutter up the steep valley walls. It fed probably on the eggs and the juveniles of several Saint Helena terrestrial and pelagic bird species and on snail
s. Like other ground-nesting birds as the Saint Helena Crake and the Giant Hoopoe
it became a victim of alien predators like cat
s and rats which were brought to Saint Helena
after 1502.
Saint Helena
Saint Helena , named after St Helena of Constantinople, is an island of volcanic origin in the South Atlantic Ocean. It is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha which also includes Ascension Island and the islands of Tristan da Cunha...
. It became extinct in the early 16th century.
When American ornithologist Alexander Wetmore
Alexander Wetmore
Frank Alexander Wetmore was an American ornithologist and avian paleontologist.-Life:Wetmore studied at the University of Kansas...
described this species from subfossil remains which were found at Prosperous Bay
Prosperous Bay Plain
Prosperous Bay Plain is an area on the north-eastern coast of Saint Helena, a British island territory in the South Atlantic Ocean. It is the site of the proposed Saint Helena Airport and is notable for its high invertebrate biodiversity.-Geography:...
, Saint Helena, he classified it into the new genus Aphanocrex. However, in 1973 American paleontologist Storrs Olson synonymised this genus with the genus Atlantisia which other representative is the Inaccessible Island Rail
Inaccessible Island Rail
The Inaccessible Island Rail is a small bird of the rail family, Rallidae. It is the only species in its genus. It is found only on Inaccessible Island in the Tristan Archipelago, and is notable for being the smallest extant flightless bird in the world...
(Atlantisia rogersi). While Olson had considered it as congenor of the Inaccessible Island Rail
Inaccessible Island Rail
The Inaccessible Island Rail is a small bird of the rail family, Rallidae. It is the only species in its genus. It is found only on Inaccessible Island in the Tristan Archipelago, and is notable for being the smallest extant flightless bird in the world...
, other scientists regarded it not even as close relative and so it was renamed into Aphanocrex. The Saint Helena Swamphen was relatively large and reached almost the size of the New Zealand Weka
Weka
The Weka or woodhen is a flightless bird species of the rail family. It is endemic to New Zealand, where four subspecies are recognized. Weka are sturdy brown birds, about the size of a chicken. As omnivores, they feed mainly on invertebrates and fruit...
(Gallirallus australis). In contrast to the Weka it was more slender. Since Saint Helena was predator free until the sixteenth century, the swamphen had lost its ability to fly but it wings were better developed like the wings of the rails from Inaccessible Island and Ascension Island
Ascension Island
Ascension Island is an isolated volcanic island in the equatorial waters of the South Atlantic Ocean, around from the coast of Africa and from the coast of South America, which is roughly midway between the horn of South America and Africa...
. Furthermore it had strong toes with long claws which give that species a good ability to climb and flutter up the steep valley walls. It fed probably on the eggs and the juveniles of several Saint Helena terrestrial and pelagic bird species and on snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
s. Like other ground-nesting birds as the Saint Helena Crake and the Giant Hoopoe
Giant Hoopoe
The Giant Hoopoe , also known as Saint Helena Giant Hoopoe or Saint Helena Hoopoe, is an extinct species of Hoopoe , known exclusively from an incomplete subfossil skeleton....
it became a victim of alien predators like cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s and rats which were brought to Saint Helena
Saint Helena
Saint Helena , named after St Helena of Constantinople, is an island of volcanic origin in the South Atlantic Ocean. It is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha which also includes Ascension Island and the islands of Tristan da Cunha...
after 1502.
Further reading
- Storrs L. Olson, Paleornithology of St Helena Island, south Atlantic Ocean, Smithsonian Contributions to Paleobiology 23 (1975)